Département de santé communautaire

Département
de santé
communautaire
Centre
hospitalier
de Verdun
INSPQ Mqnlréal
465
1907
55
I!
000 9450
000, boul. LaSalle VERDUN (Québec) H4G 2A3
761-3551
Département
Santé
Communautaire
CENTRE HOSPITALIER 0 1 V l R U U N
4000, BOUL. LASALLl
VERDUi^, P, Q.
H4G 2A3
FLUIDES DE COUPE
Guide à l ' u s a g e des i n t e r v e n a n t s
Jacques Gagnon
Hygiéniste i n d u s t r i e l
DSC Verdun
Février
1987
C ô - e x - l
FLUIDES DE COUPE
Guide à l ' u s a g e des i n t e r v e n a n t s
Jacques Gagnon
Hygiéniste industriel
DSC Verdun
Février
1987
Ce guide se d i v i s e en t r o i s
parties.
g e s , e s t une f i c h é d e s t i n é e à f a c i l i t e r
saires
à l'évaluation
deuxième v i e n t
a u s s i aider
des
préciser
risques
ce qui
est
des 2 premières
parties.
l a c u e i l l e t t e des i n f o r m a t i o n s
que représentent
demandé dans
l e s i n t e r v e n a n t s à préparer
l a t r o i s i è m e c o n s i s t e en un r e c u e i l
La p r e m i è r e , q u i compte t r o i s
la
néces-
l e s h u i l e s de coupe.
première.
pa-
La
Elle
devrait
leurs sessions d'information.
Enfin,
des t e x t e s qui ont s e r v i
à
l'élaboration
PREMIERE PARTIE
F i c h e d e s t i n é e à f a c i l i t e r l a c u e i l l e t t e des i n f o r m a t i o n s
FLUIDES DE COUPE
1)
2)
Fréquence d ' u t i l i s a t i o n des f l u i d e s de coupe
A)
Nombre d ' h e u r e s (par j o u r , par s e m a i n e . . . ) consacrées à l ' u s i n a g e .
B)
Que f a i t le t r a v a i l l e u r l o r s q u ' i l ne f a i t pas d ' u s i n a g e .
Nature du f l u i d e
A)
Q u ' e s t - c e qui est é c r i t s u r l e s é t i q u e t t e s et l e s f i c h e s techniques et
toxicologiques.
B)
a)
Type de f l u i d e ( i n s o l u b l e , émulsion ou s y n t h é t i q u e ) .
b)
Nature de l ' h u i l e
c)
Additifs.
(minérale,
animale...).
Questions et o b s e r v a t i o n s .
a)
A j o u t e - t - o n quelque chose au f l u i d e ?
Non
Oui
»
Q u ' e s t - c e que c ' e s t ?
Dans q u e l l e p r o p o r t i o n ?
b)
Quel type d ' u s i n a g e
effectue-t-on?
Quelle e s t l a nature du m a t é r i e l u s i n é ?
Quel type de f l u i d e
utilise-t-on?
Mode d ' a p p l i c a t i o n et f i l t r a t i o n du f l u i d e
A)
Mode d ' a p p l i c a t i o n
Comment l e f l u i d e e s t - i l
appliqué?
Y a - t - i l un système de v e n t i l a t i o n
locale?
Y a - t - i l des " s p l a s h guards"?
Y a - t - i l p r o j e c t i o n de g o u t t e l e t t e s
Un b r o u i l l a r d d ' h u i l e e s t - i l
visible?
Les s u r f a c e s de t r a v a i l s o n t - e l l e s
B)'
d'huile?
huileuses?
filtration
Existe-t-il
l'huile
Est-ce
un
mécanisme
pour
retirer
les
copeaux
de
usée?
qu'il
s'agit
uniquement
d'un
bac de sédimentation
tank")?
E s t - c e q u ' i l y a a u s s i une u n i t é de f i l t r a t i o n ?
E v a l u a t i o n des contaminants émis dans
l'air
Une é v a l u a t i o n environnementale e s t - e l l e
nécessaire?
S i o u i , q u e l s contaminants d o i t - o n é c h a n t i l l o n n e r ?
Contact
A)
métalliques
Protection personnelle
Des équipements s o n t - i l s
Sont-ils
disponibles?
imperméables?
Le t r a v a i l l e u r l e s
porte-t-il?
("settling
3.
B)
Fréquence d ' e x é c u t i o n des tâches
Enumérer et d é c r i r e les tâches où i l
y a contact avec des f l u i d e s de
coupe.
C)
Nature du contact
Décrire l e ( s )
D)
contact(s).
Surface de contact
Identifier
l a p a r t i e du corps qui est en contact
avec
le
fluide
de
coupe.
E)
Durée du contact
Déterminer l a durée des c o n t a c t s .
6)
Hygiène e t mesures p r é v e n t i v e s
En vous r é f é r a n t
aux e x p l i c a t i o n s qui s u i v e n t ,
i n f o r m a t i o n que vous j u g e r e z p e r t i n e n t e .
indiquez ci-dessous
toute
DEUXIEME PARTIE
Explications sur les informations à r e c u e i l l i r et
sur c e l l e s à donner aux t r a v a i l l e u r s et à l'employeur
FLUIDES DE COUPE
Vous t r o u v e r e z ci-dessous des e x p l i c a t i o n s sur les i n f o r m a t i o n s qu'on vous
demande de r e c u e i l l i r .
trouvent en annexe.
Ces e x p l i c a t i o n s
s'appuient
sur
des t e x t e s
qui
se
La d e r n i è r e s é r i e d ' e x p l i c a t i o n s se rapporte aux mesures
d'hygiène et aux mesures p r é v e n t i v e s .
E l l e a été conque non seulement
pour
vous aider à r e c u e i l l i r des i n f o r m a t i o n s , mais aussi et s u r t o u t pour vous a i der à préparer vos sessions d ' i n f o r m a t i o n .
1)
Fréquence d ' u t i l i s a t i o n des f l u i d e s de coupe
A)
Nombre d'heures (par j o u r , par s e m a i n e . . . ) consacrées.à l ' u s i n a g e .
B)
Que f a i t l e t r a v a i l l e u r
l o r s q u ' i l ne f a i t pas d ' u s i n a g e .
— * Ce qu'on veut s a v o i r , c ' e s t s i ce q u ' i l
fait
en p l u s de l ' u s i n a g e
peut rendre sa peau plus s e n s i b l e aux attaques des f l u i d e s de coupe.
La capacité de l a peau à a g i r comme une b a r r i è r e peut ê t r e
dimi-
nuée à l a s u i t e de d i v e r s dommages:
-
dommages mécaniques ( c f . p. 10-2 et
10-5):
coupure ( m a n i p u l a t i o n de pièces ayant des arêtes
frottement ( u t i l i s a t i o n d ' o u t i l s
vibrants...)
abrasion (manipulation de m a t é r i e l
-
dommages chimiques ( c f . p . 10-6 et
.
2)
rugueux...)
11-1):
contacts avec des substances chimiques
autres dommages (physiques,
vives...)
irritantes.
biologiques...).
Nature du f l u i d e
On d i s t i n g u e 3 p r i n c i p a u x types de f l u i d e de coupe ( c f . p. 2-1, 2-2, 5-11,
7 - 2 , 7-3 et 8-1 à 8 - 3 ) :
les h u i l e s i n s o l u b l e s (100% d ' h u i l e ) ;
l e s h u i l e s s o l u b l e s ou émulsions ( l e f l u i d e concentré c o n t i e n t
entre
60 et 85?£ d ' h u i l e ) ;
l e s f l u i d e s synthétiques (contiennent peu ou pas d ' h u i l e ) .
Les
fluides
synthétiques
qui
f l u i d e concentré) sont d i t s
contiennent
de l ' h u i l e
"semi-synthétiques".
(entre
5 et
25% du
Il
est
important
additifs
qu'il
de c o n n a î t r e
contient
le
puisque
type de f l u i d e
utilisé
ainsi
les
cutanés
vont
problèmes
que
les
d'abord
dépendre de l a nature de tous ces p r o d u i t s .
Les h u i l e s i n s o l u b l e s vont s u r t o u t , ê t r e responsables des boutons
("oil
a c n e " ) , des kératoses,
d'huile
de l a mélanose et du cancer t a n d i s que les
émulsions et les f l u i d e s synthétiques v o n t , en r a i s o n des a d d i t i f s
contiennent,
p.
1 —1,
qu'ils
ê t r e responsables s u r t o u t des d e r m a t i t e s eczématiformes
4-2,
informations
6-1
sur
et
les
6-2).
Il
fluides
existe
de coupe:
2
(1)
façons
lire
de
(cf.
recueillir
les é t i q u e t t e s
des
et
les
f i c h e s techniques et t o x i c o l o g i q u e s et (2) poser des questions et observer
l e s o u t i l s et les f l u i d e s .
3e vous recommande de r e c u e i l l i r
l e s 2 types
d'information.
A)
L i r e les é t i q u e t t e s et les f i c h e s techniques e t
a)
toxicologiques.
Huiles i n s o l u b l e s , émulsions e t f l u i d e s s y n t h é t i q u e s :
comment l e s
reconnaître? ( c f . p. 8 - 1 1 ) .
—^Attention:
é v i t e z les conclusions h â t i v e s f a i t e s h p a r t i r
s e u l élément
d'un
d'information.
Huiles insolubles
"Cutting
oil",
l'opération
"neat
suivi
cutting
du
mot
oil",
"oil"
ou t o u t
autre mot
(ex.:"honing
oil",
désignant
"tapping
oil"...)
N.B. :
"Cutting
fluid"
ne d o i t
pas ê t r e
confondu avec
"cutting
l'expression
utilisée
oil".
N.B.:
Le mot " o i l "
peut
apparaître
dans
pour i d e n t i f i e r une h u i l e s o l u b l e .
Insoluble
Densité ( " s p e c i f i c g r a v i t y " ) i n f é r i e u r e à 1 ( 0 . 8 5 - 0 . 9 0 ) .
Emulsions
"Water m i s c i b l e " , "water s o l u b l e " ou " e m u l s i f i a b l e " ( c f . p. 8 - 2 ) .
Soluble
L
a i t e uappelées
x , opaque" c o( cofl .a np.
-2).
Sont
t " , 7"suds"
ou "mystic ( c f . p. 7-2 et 9 - 2 ) .
Fluides synthétiques
"Chemical"—•"fluid",
"emulsion", " c o d a n t " ,
"solution". ..(cf.
p.
8-11).
Soluble.
C l a i r , transparent ( c f . p. 7-2 e t 8 - 1 ) .
Nature de l ' h u i l e
"Minerai o i l s " ( c f . p. 4 - 1 , 4-2 et 8 - 5 ) .
L
^
Huiles d ' o r i g i n e minérale dérivées s u r t o u t du
p é t r o l e ; les h u i l e s anthracéniques, i . e . d é r i vées du goudron de h o u i l l e , sont rarement u t i l i sées: on les t i e n t pour responsables de nombreux cancers.
^
Les HPA ne sont pas e x c l u s i f s aux h u i l e s a n t h r a céniques; on peut en r e t r o u v e r dans les h u i l e s
d ' o r i g i n e p é t r o l i è r e ( c f . p. 1 2 - 1 ) .
• Naphtenic ( s a t u r a t e d , r i n g - t y p e s t r u c t u r e s ) .
P a r a f f i n i c ( s t r a i g h t on branched chain s a t u r a t e d
hydrocarbons).
" F a t t y o i l s " ( c f . p. 7 - 2 , 7-3, 8-5 et 8 - 6 ) :
^
Huiles d ' o r i g i n e animale ou v é g é t a l e ;
elles
peuvent ê t r e u t i l i s é e s comme t e l l e s (ex. blends
of f a t t y and mineral o i l s )
ou encore ajoutées
comme a d d i t i f s (ex. s u p e r - f a t t e d emulsions);
les h u i l e s grasses améliorent l a l u b r i f i c a t i o n
("polar additives").
Présence probable de b a c t é r i c i d e ( c f . p. 3-4
(44)).
/
Additifs
Les a d d i t i f s sont responsables de l a p l u p a r t des d e r m a t i t e s
al-
l e r g i q u e s associées aux f l u i d e s de coupe»
L ' i d e n t i f i c a t i o n des a d d i t i f s présents dans un f l u i d e est assez
difficile
car c e u x - c i ne sont habituellement
l e s contenants ou sur l e s f i c h e s .
pas indiqués sur
Plus f a c i l e s à t r o u v e r sont
l e s c a r a c t é r i s t i q u e s des f l u i d e s à p a r t i r desquels on peut supposer l a présence de c e r t a i n s a d d i t i f s ( c f . p. 9 - 8 ) .
Recherchez sur les é t i q u e t t e s t o u t e i n f o r m a t i o n pouvant mener à
l ' i d e n t i f i c a t i o n de ces a d d i t i f s ( c f . p . 12-2 à 1 2 - 4 ) .
Consul-
tez l e g l o s s a i r e s i des termes vous sont inconnus ( c f . p. 8-21
à 8-23).
Vous trouverez ci-dessous des notes sur quelques
i)
additifs:
Pression extrême ou "extreme pressure" (EP)
-
Présence probable de s o u f r e , de c h l o r e ou de phosphore
(sulfurized,
chlorinated,
sulfo-chlorinated...oil)(cf.
p. 7 - 2 , 7-3, 8-6 et 8 - 7 ) .
-
Une émulsion contenant des a d d i t i f s
d'extrême
est généralement q u a l i f i é e d ' " h e a v y - d u t y "
-
pression
( c f . p. 8 - 8 ) .
Le c h l o r e peut ê t r e responsable de problèmes de c h l o r a c né ( c f . p. 1-2 e t 3 - 1 ) .
-
Le c h l o r e peut se dégager sous forme d ' a c i d e
chlorhydri-
que ( c f . p. 5 - 5 ) .
ii)
Bactéricides
-
Ce sont s u r t o u t (mais pas uniquement) dans les émulsions
que des b a c t é r i e s
vont
se développer
(cf.
p.
5-3
et
8-9).
-
Des b a c t é r i c i d e s
vont
leur
être
ajoutés
afin
d'éviter
qu' e l l e s ne se décomposent et que des odeurs ne se f o r ment ( c f . p. 1-2 et 5 - 3 ) .
-
Si on surcharge l e f l u i d e de b a c t é r i c i d e s , on a c c r o î t
le
risque de s e n s i b i l i s a t i o n à c e u x - c i ( c f . p. 1-2 et 3 - 2 ) .
-
La p l u p a r t des b a c t é r i e s q u i vont se développer dans les
non pas pour 1 1 u t i l i s a -
h u i l e s vont ê t r e dommageables,
t e u r , mais p l u t ô t pour l ' h u i l e q u i r i s q u e de se décomposer.
I l est à noter t o u t e f o i s que des b a c t é r i e s
conte-
nues dans des h u i l e s ont d é j à é t é tenues responsables de
c e r t a i n s problèmes de santé ( c f . p . 9 - 2 , 9-4 e t 9 - 5 )
iii)
Agent m o u i l l a n t et agent a n t i - c o r r o s i o n dans les
fluides
synthétiques ( c f . p; 4 - 3 , 5-3 et 9-2 à 9 - 4 )
-
Agent m o u i l l a n t ( " s u r f a c e a c t i v e agent")
utilisé
pour
réduire
la
tension
superficielle
de
l'eau
goutte
a
d ' eau
sans
avec
agent.
agent
t r i é t h a n o l a m i n e est souvent
utilisé
Agent a n t i - c o r r o s i o n ( " c o r r o s i o n
n i t r i t e de sodium est souvent
-
inhibitor")
utilisé.
La combinaison amine + n i t r i t e peut mener à l a formation
de nitrosamine (ex.
nitrosodiéthanolamine).
Poser des questions et observer les o u t i l s et l e s
a)
fluides.
Déterminer s i on a j o u t e ou non quelque chose au f l u i d e ,
i ) Est-ce qu'on a j o u t e de l ' e a u au f l u i d e ?
ii)
Oui=
émulsion ou f l u i d e s y n t h é t i q u e .
Non=
huile
Si
insoluble.
on a j o u t e
de l ' e a u
au f l u i d e ,
dans q u e l l e
proportion
le
fait-on?
émulsion = 1/5 à 1/50
f l u i d e s y n t h é t i q u e = 1/10 à 1/200
iii)
Est-ce qu'on a j o u t e autre chose au f l u i d e ?
Ca p o u r r a i t
être
un
autre
fluide
(ex."blend
of
fatty
and
du
type
mineral o i l s " ) .
b)
Essayer
de
déterminer
la
nature
de
l'huile
à partir
d'usinage et de l a nature du m a t é r i e l u s i n é .
On d o i t
garder en mémoire les p r o p r i é t é s
r e s p e c t i v e s de l ' e a u
et
de l ' h u i l e ( c f . p . 1 - 1 , 7-2 et 9-3)
eau:
refroidissement
huile:
ainsi
que
lubrification
les
caractéristiques
de
coupe
des
divers
fluides
( c f . p. 5-2, 7-3. et. 7 - 4 ) .
huiles insolubles:
"heavy c u t s " , " f i n e
fluides synthétiques:
i)
ii)
Identifier
finishes"
" h i g h e r speed c u t t i n g o p e r a t i o n s "
l e type d'usinage e f f e c t u é ( c f . p. 8-12 à 8 - 2 0 ) .
Essayer de c o n n a î t r e l a nature du m a t é r i e l usiné ( c o n s u l t e r
la
l i s t e q u i se trouve à l a page 9 - 9 ) .
N.B.:
Des
métaux
peuvent
se.
retrouver
dans
possiblement causer des dermatites ( c f .
.
l'huile
et
p.2-2).
n i c k e l ( c f . p . 1-2)
. . c o b a l t ( c f . p. 11-6)
iii)
Déterminer
l e type d ' h u i l e qui p o u r r a i t
7-7 et 9 - 1 1 ) .
être u t i l i s é
(cf.
p.
3)
Mode d ' a p p l i c a t i o n et f i l t r a t i o n , du f l u i d e
a)
Mode d ' a p p l i c a t i o n
La
propreté
des
surfaces
de
travail
va
dans
une
certaine
mesure
dépendre du mode d ' a p p l i c a t i o n du f l u i d e .
I l e x i s t e 6 façons d ' a p p l i q u e r l e f l u i d e de coupe ( c f . p. 8 - 1 1 ) :
"flood"
"mist"
" h i g h pressure"
"high velocity
jet"
"hand"
"immersion"
Les 3 p r i n c i p a l e s sont ( c f . p. 5-2)
"flood":
- écoulement du f l u i d e sur l a pièce à u s i n e r ,
"mist":
-
utilisé
lorsque
l a première
façon
("flood")
n'est
pas
le refroidissement
est
applicable.
-
la
visibilité
est m e i l l e u r e
mais
moins bon.
- v e n t i l a t i o n l o c a l e recommandée,
"hand":
- a p p l i c a t i o n manuelle.
Parmi ces 3 d e r n i è r e s , l a plus fréquente est l a première
^
3 à 5 g a l l o n s par minute par " n o z z l e "
("flood"):
sont nécessaires d ' o ù
la
" n é c e s s i t é " de mettre des "splash guards"
( c f . p. 5-4, 7 - 4 , 7-6 et 7 - 8 ) .
Une
fois
déterminé
le
mode
d'application,
répondre
aux
questions
suivantes:
y a - t - i l un système de v e n t i l a t i o n
locale?
y a - t - i l des " s p l a s h guards"?
y a - t - i l p r o j e c t i o n de g o u t t e l e t t e s
un b r o u i l l a r d d ' h u i l e e s t - i l
visible?
l e s surfaces de t r a v a i l s o n t - e l l e s
b)
d'huile?
huileuses?
Filtration
L'enlèvement des copeaux m é t a l l i q u e s contenus dans l ' h u i l e va diminuer
l e r i s q u e de coupure aux mains ( c f . p . 3 - 2 ) .
On peut
n'enlever
habituellement.
que
les
gros
copeaux.
On peut aussi enlever
C'est
ce
qui
les p e t i t s copeaux.
se
fait
Cela est
nécessaire lorsque l a f i n i t i o n de l a pièce usinée d o i t ê t r e de grande
qualité
("grinding",
"honing",
"lapping",
"deep-hole
boring")(cf.p.
7-4).
Répondre aux questions s u i v a n t e s :
Existe-t-il
un mécanisme pour r e t i r e r
les copeaux m é t a l l i q u e s de
i
l ' h u i l e usée?
Est-ce q u ' i l s ' a g i t uniquement d ' u n bac de sédimentation
-
tank)?
Est-ce q u ' i l y a aussi une u n i t é de f i l t r a t i o n
(settling
( c f . p. 3-4 et 3 - 5 ) .
Evaluation des contaminants émis dans l ' a i r .
La norme de 5 mg/m^ ne s ' a p p l i q u e qu'au b r o u i l l a r d d ' h u i l e m i n é r a l e .
Il
est donc i n u t i l e de v é r i f i e r c e t t e norme lorsque l e f l u i d e de coupe est un
f l u i d e s y n t h é t i q u e ( c f . p. 5 - 1 ) .
Actuellement
l'IRSST ne peut analyser que les
brouillards
issus
d'huile
i n s o l u b l e dans l ' e a u ( s o l u b l e dans l e CCI4).
Il
n'existe
Cependant,
pas de norme- pour
il
peut e x i s t e r
les b r o u i l l a r d s
de f l u i d e s
des normes pour c e r t a i n s
synthétiques.
des a d d i t i f s
qu'ils
contiennent ( c f . p. 5 - 3 ) .
Les
huiles
solubles
et
les
fluides
synthétiques
vont
faire
moins
de
b r o u i l l a r d que les h u i l e s i n s o l u b l e s ( c f . p. 5 - 4 ) .
Les b r o u i l l a r d s d ' h u i l e sont p r o d u i t s de 3 façons ( c f . p. 5-2 et 5 - 3 ) :
mécaniquement,
en
raison
de l a
force
centrifuge
due à l a
rotation
rapide de l ' o u t i l ou de l a pièce usinée,
thermiquement par v a p o r i s a t i o n et condensation subséquente du f l u i d e ,
i n t e n t i o n n e l l e m e n t en appliquant l e f l u i d e sous forme de b r o u i l l a r d .
La formation de b r o u i l l a r d durant l ' u s i n a g e va, dans une c e r t a i n e mesure,
dépendre de l a
charge
( " s e v e r i t y " ) ( c f . p.
sur
l'outil
et
de
la
chaleur
générée
5-7 et 9 - 3 ) .
Le degré de " s e v e r i t y "
brouillard
appliquée
qu 1 i l
e t donc l a p o s s i b i l i t é
va dépendre du type d ' o p é r a t i o n
et
y ait
formation de
de l a nature du m a t é r i e l
usiné ( c f . p. 9 - 9 ) .
Contact
Le risque de d e r m a t i t e va dépendre non seulement de l a nature du f l u i d e ,
mais aussi du degré de contact e n t r e ce d e r n i e r et l a peau du t r a v a i l l e u r .
A)
Protection personnelle
Le t r a v a i l l e u r
porte-t-il
des gants, un t a b l i e r ,
un autre
équipement
d e s t i n é à p r é v e n i r les contacts cutanés?
Ces
équipements
sont-ils
imperméables?
(gants
de
coton
VS
gants
caoutchoutés)•
Le t r a v a i l l e u r l e s p o r t e - t - i l
B)
toujours?
Fréquence d ' e x é c u t i o n des tâches
Enumérèr
les
tâches
au
cours
desquelles
les
travailleurs
contacts avec les f l u i d e s de coupe ( l e s d é c r i r e s i
Faire
pièces
une d i s t i n c t i o n
usinées...)
et
entre
les
les
tâches
tâches
des
possible).
régulières
occasionnelles
ont
(manipulation
("set-up",
de
vidange
d'huile...).
C)
Nature du contact
Immersion (plonger les mains dans un bassin contenant de l ' h u i l e . . . ) .
Projection
(éclaboussures...)
S u p e r f i c i e l (manipuler des pièces dont l e s surfaces sont
D)
huileuses...)
Surface de contact
Ce n ' e s t
pas
seulement
une question
de
localisation
c ' e s t .aussi une question d'étendue ( " c o n t a c t
Identifier
("location");
area").
l a p a r t i e du corps qui est en contact
avec
le
fluide
de
I
coupe (main, a v a n t - b r a s , c u i s s e , abdomen...).
N.B.:
Le t r a v a i l l e u r
q u i s ' a p p u i e sur sa machine, c e l u i q u i
des pièces usinées sur
lui
pour
les t r a n s p o r t e r :
appuie
ce sont
là
des contacts dont on d o i t t e n i r compte.
E)
Durée du contact
Continue (des contacts peuvent ê t r e c o n t i n u s durant l ' e x é c u t i o n
d'une
tâche o c c a s i o n n e l l e ) .
Fréquent
Occasionnel (des contacts peuvent ê t r e occasionnels durant
d'une tâche r é g u l i è r e • • e x .
l'exécution
r e t i r e r son gant pour toucher l a surface
d'une pièce q u i v i e n t d ' ê t r e u s i n é e ) .
6)
Hygiène e t mesures préventives
Cette
dernière
section
va s u r t o u t
vous
servir
à élaborer
vos
sessions
d'information.
A)
Prévenir
l'exposition
Les p r i n c i p a u x moyens pour prévenir l ' e x p o s i t i o n des t r a v a i l l e u r s
huiles
de
coupe
sont
pare-éclaboussures,
la
la
substitution,
ventilation
et
l'aménagement
l'automatisation
aux
d'écrans
(cf.
p.
3-4
( 4 2 ) , 4-3 et 5 - 3 ) .
a)
La s u b s t i t u t i o n
Il
s'agit
pour
d'utiliser
l e f l u i d e qui représente l e moins de risque
1'utilisateur.
utiliser
un
fluide
(huile
minérale)
cancérigènes (HPÂ) auront été e x t r a i t e s
( c f . p. 1 - 2 , 5-4, 7-5 et
duquel
les
("solvent
substances
extraction")
12-8).
u t i l i s e r un f l u i d e qui ne c o n t i e n t pas de substances
(nitrites)
pouvant
p. -5-4
mener à l a
formation de nitrosamines
(cf.
et
12-8).
utiliser
un
fluide
contenant
(anti-mist additive)(cf.p.
5-4).
un
agent
anti-brouillard
N.B.:
Y aller
avec
prudence
sinon on risque
de remplacer
une
substance dangereuse par une substance p l u s dangereuse.
b)
L'aménagement d'écrans pare-éclaboussures
Ce sont des moyens destinés à c o n t e n i r l e s p r o j e c t i o n s
d'huile.
I l s devraient permettre à l'employeur de sauver de l ' h u i l e
(cf.p.
3-5
(56)).
I l s vont c o n t r i b u e r à garder les surfaces de t r a v a i l et les planchers
propres.
" (cf.p.
Les risques
de chute par
glissade
vont
donc ê t r e
réduits
1-1).
Conception des écrans ( c f . p . 5-4, 7-6 et 7 - 8 ) .
c)
La v e n t i l a t i o n .
V e n t i l a t i o n l o c a l e ( c f . p. 5-4)
V e n t i l a t i o n générale ( c f . p .
d)
5-5)
L'automatisation
Permet
de r é d u i r e
au minimum les
contacts
avec les
fluides
(cf.
p.
7-8)
Vêtements
a)
Vêtements p r o t e c t e u r s
Les vêtements p r o t e c t e u r s
temporaires ( c f . p . 5-6 et
Les
vêtements
peuvent
vont
faire
qu'opèrent
ê t r e , considérés
comme des mesures
13-1).
protecteurs
cependant
appareils
doivent
réduire
augmenter
les
les
les
contacts
risques
travailleurs
cutanés.
Ils
d'accident
(les
tournent
à
grande
v i t e s s e ) ( c f . p . 2-3 et 4 - 3 ) .
Les
tabliers
mis
à
la
disposition
des
travailleurs
doivent
imperméables a f i n d ' é v i t e r que l e u r s vêtements ne se s o u i l l e n t
1-2 et 3-4 ( 3 4 ) ) .
être
(cf.p.
Des gants r é s i s t a n t s à l ' h u i l e préviennent non seulement les
cutanés, mais aussi les coupures et l e s é g r a t i g n u r e s ( c f . p.
b)
contacts
5-6),
Vêtements de t r a v a i l
Les vêtements et
fois
les sous-vêtements doivent
par semaine.
Il
ê t r e changés au moins 2
est même p r é f é r a b l e de les changer à tous
les
j o u r s ( c f . p . 1 - 2 , 2 - 3 , 3-4 ( 3 7 ) , 4-3 et 5 - 5 ) .
Les t r a v a i l l e u r s - d e v r a i e n t changer de vêtements a u s s i t ô t
leur
journée
de t r a v a i l terminée ( c f . p . 3-4 ( 3 7 ) ) .
Les t r a v a i l l e u r s ne devraient pas garder de c h i f f o n s s o u i l l é s dans l a
poche
arrière
13-3).
de l e u r
Pour
pantalon
s'essuyer
les
(cf .p.
mains,
1-2,
ils
3-4
(38),
devraient
4-3,
5-5
utiliser
et
des
s e r v i e t t e s à usage unique.
Pour
laver
des
vêtements
souillés
p r é f é r a b l e au lavage à l ' e a u ( c f . p .
d'huile,
le
nettoyage
à sec
est
13-3).
Lavage
L'accès aux i n s t a l l a t i o n s s a n i t a i r e s d o i t ê t r e f a c i l e .
De l ' e a u , du savon
et des s e r v i e t t e s de papier j e t a b l e s doivent ê t r e d i s p o n i b l e s
(cf.p.
1-2
et 3-2 ( 2 1 ) ) .
Les t r a v a i l l e u r s d e v r a i e n t pouvoir prendre une douche après l e u r quart de
t r a v a i l ( c f . p . 1 - 2 et 4 - 3 ) .
Le lavage des mains d o i t
être
fréquent sans cependant l ' ê t r e
trop:
3-4
lavages par j o u r ne d e v r a i e n t pas causer de problèmes, t a n d i s que 10 à 20
peuvent e n t r a î n e r des dermatites ( c f . p . 3-2 ( 2 2 ) ) .
Ne pas se laver
abrasives.
les mains avec des s o l v a n t s
e t / o u des
pâtes
U t i l i s e r p l u t ô t des poudres nettoyantes dont l e p r i n c i p e
actif
n ' e s t pas i r r i t a n t ,
pétroliers
des savons aux sulfones e t / o u des p r o d u i t s
sans eau ( c f . p . 1 - 2 , 3-2 ( 2 1 ) , 4-3 et 5 - 5 ) .
récurants
F a i r e a t t e n t i o n aux p r o d u i t s sans eau ( " w a t e r l e s s hand c l e a n s e r s " ) :
contiennent habituellement entre 15 et 20% de solvant
3-3 (24, 25 et
3-2 (23)
et
26)).
Bien assécher les mains après les a v o i r lavées ( c f . p .
Utiliser
(cf.p.
ils
une l o t i o n hydratante
5-5).
à l a f i n de l a journée de t r a v a i l
(cf.p.
4-3 et .5-5).
D)
Crèmes
L ' u t i l i s a t i o n d'une crème p r o t e c t r i c e diminue l e contact des h u i l e s
l a peau et f a c i l i t e l e lavage ( c f . p .
4-3).
Aucune crème ne protège à l a f o i s contre les h u i l e s ,
f l u i d e s à base d'eau ( c f . p .
avec
les s o l v a n t s et
les
5-6).
Crèmes o l é o f u g e s : protègent contre les h u i l e s
Crèmes hydrofuges:
protègent
contre
l'eau
(cf.p.
1-2,
3-4 (35 & 36)
et
12-12).
L'action
protectrice
des
crèmes
n'est
pas
très
longue:
en
appliquer
souvent ( c f . p . 3-4 ( 3 6 ) ) . L'usage de crème peut représenter c e r t a i n s inconvénients
et
E)
12-11).
Rôle de l'employeur ( c f . p . 3-4 (40 & 4 1 ) ) .
(cf.p.5-6,
12-10
TROISIEME PARTIE
Recueil de textes
BIBLIOGRAPHIE
1)
Key, M. M., Huiles de coupe, dans Encyclopédie de médecine, d'hygiène et
de s é c u r i t é du t r a v a i l , BIT, V o l . 1, pp. 812-814, Genève, 1973.
2)
Key, M.M., J . S . T a y l o r et C. Yang, Grinding and c u t t i n g F l u i d s , dans Encyclopaedia o f Occupational Health and S a f e t y , ILO, V o l . 1, pp. 979-981, Genève, 1983.
3)
N a t i o n a l Safety C o u n c i l , C u t t i n g O i l s Emulsions and Drawing Compounds, Dat a Sheet 1-719-86 paru dans N a t i o n a l Safety and Health News, March 1986.
4)
Durocher, L.P. et N. Paquette, Huiles de coupe et dermatoses cutanées,
L ' u n i o n médicale du Canada, Tome 115, pp. 730-732, Octobre 1986.
5)
NIOSH- Technical Report, C o n t r o l o f exposure t o metalworking f l u i d s , DHEW
(NIOSH), P u b l i c a t i o n no. 78-165.
6)
R y c r o f t , R . J . G . , C u t t i n g F l u i d s , O i l and L u b r i c a n t s , dans Occupational and
I n d u s t r i a l Dermatology, Maibach, H . I . and G.A. G e l l i n , Chicago, 1982.
7)
Cookson, 3 . 0 . , Machine Tool Design and Use i n R e l a t i o n t o C u t t i n g F l u i d s ,
Ann. Occup. Hyg., V o l . 14, pp. 181-190.
8)
Springborn, R.K., C u t t i n g and g r i n d i n g f l u i d s :
s e l e c t i o n and a p p l i c a t i o n ,
American Society of Tool and Manufacturing Engineers, Michigan, 1967.
9)
Underwood, J . G . , Health Hazards from C u t t i n g F l u i d s , The Insurance Technic a l Bureau, Memorandum t o the Accident O f f i c e s A s s o c i a t i o n AOA-M/010,
A p r i l 1984.
10)
B i r d , M.G., I n d u s t r i a l S o l v e n t s :
Some Factors A f f e c t i n g t h e i r Passage
I n t o and Through the S k i n , Ann. Occup. Hyg., V o l . 24, No.2, pp. 235-244.
11) Alomar, A . , L. Conde-Salazar et C. Romaguera, Occupational Dermatoses from
C u t t i n g O i l s , Contact D e r m a t i t i s , V o l . 12^ pp. 129-138, 1985.
12) DSC de 1 ' H ô p i t a l du Sacré-Coeur, Eléments du programme de s u r v e i l l a n c e
médico-environnementale pour l e s t r a v a i l l e u r s exposés aux b r o u i l l a r d s et
f l u i d e s de coupe ou de r e f r o i d i s s e m e n t , Septembre 1984.
13) O i l : a w o r k e r ' s guide t o the h e a l t h hazards and how t o f i g h t them,
Society, f o r S o c i a l R e s p o n s i b i l i t y i n Science, 1975.
British
Huilez
de
coupe
H u i l e s de c o u p e
T M i l . K V C I t l . C O M P O S I T I O N 1»liS K I . U 1 D K S
l»K H i : m o | h ! S S i : M K N T ( S Y N T I l f c T I O l E S )
Ghw
D a n s les m a c h i n e s d ' u s i n a g e |>:*r e n l è v e m e n t d e
inetul, l'arête vivo d ' u n outil d u r d é t a c h e des c o p e a u x
pur des movens mécaniques divers: tournage, rabotage,
f a ç o n n a g e , ' perçaire. fraisage, alésage ou m a n d r i n a g e .
P r e s q u e t o u j o u r s , j ' a t t a q u e d u m ê l a i se t r a d u i t p a r le
d é g a g e m e n t d u n e q u a n t i t é d e c h a l e u r q u i . si elle n ' e s t
p a s d i s s i p é e , p e u t p r o v o q u e r le s o u d a g e d u m é t a l à la
p o i n t e d e r o u i il. le r a m o l l i s s e m e n t d e la p o i n t e d e
l ' o u t i l et la d i s t o r s i o n d e la p i è c e a t r a v a i l l e r . Le
n i e u l a g e est u n e o p é r a t i o n d ' e n l è v e m e n t d e m é t a l p a r
f r o t t e m e n t a u m o y e n d ' u n o u t i l , la m e u l e , d o n t les
grains abrasifs agissent c o m m e a u t a n t d outils de coupe
en ininiatlire.
Les huiles - ou lluides
d e c o u p e ont d e u x Fonctions
principales:
a) refroidir la pièce a I r a v n i l l e r et l ' o u t i l p o u r p r é v e n i r
le> déirsMs provoqué:» p a r la c h a l e u r ;
h) lubrifier,
c V > t - a - d i r e r é d u i r e la c h a l e u r d e f r o t l e m e n t à l ' i n t e r f a c e c o p e a u - o u t i l cl e n t r e l ' u n i il et la
surface de métal fraîchement découverte.
Ils o u i p o u r f o n c t i o n s s e c o n d a i r e s d e c h a s s e r les
c o p e a u x e t les h o u e s tie n i e u l a g e , tic r é d u i r e le d u r c i s s e m e n t d e f a t i g u e d u m é t a l u s i n é et d e p r o t é g e r la
p i è c e t r a v a i l l é e c o n t r e l ' o x y d a t i o n . S u r les m a c h i n e s
r a p i d e s , c o m m e les t o u r s a u t o m a t i q u e s , o n p e u t e m p l o y e r les h u i l e s d e c o u p e eu t r è s g r a n d e q u a n t i t é .
Solutions aqueuses doul la teneur eu huile émuisiflée esl
minime ou nulle. Le lluide concentré est dilue dans le rapport
de I : lu à 1 ; \ÎU0 suivant les applications, à p l i H-Ml.
I. AnlieurrosiiMi, par exemple hydroxylamines, nil ri I es inorganiques el organiques, nitrates pour stabiliser te nitrite.
Savons et surfactiTs
3. Accélérateurs de melange, par exempte glycols 1 .
4. Ilarlëricidcs
5. Agents «le conditionnement de l'eau, pur exempte phosphates el liorales
•i. Auliuiouf.se, p;ir i-xeuiple silicones'.
7. ('.ulul ants
1
\ 11 « I i 11 f H i|ui m- l i t ' u r c u t pu» thuitt tonU-s le» p r é p u r i t l i o n s .
Anirrittui In'luntrint lli/i/icite Assoniiili'iri Journal, t'JGGi
(l/u/trèit
Risques
L e s sols g l i s s a n t s d u f a i t d e l ' h u i l e r é p a n d u e d e s
m a c h i n e s - o u t i l s a u g m e n t e n t c o n s i d é r a b l e m e n t la p r o b a b i l i t é d e s c h u t e s q u i , si elles s e p r o d u i s e n t o u
voisinage do m a c h i n e s rapides, p e u v e n t être très lourd e s d e c o n s é q u e n c e s . Le r i s q u e le p l u s g r a v e d e m e u r e
n é a n m o i n s celui q u i m e n a c e la s a n l é d e s t r a v a i l l e u r s
Types <le fluides. Il e x i s t e t r o i s g r a n d e s c a t é g o r i e s
c h a r g é s d e la c o n d u i t e d e c e s m a c h i n e s . L e s m a i n s e t
les tiras d e s s e r v a n t s d e m a c h i n e , d e s o u t i l l e u r s e t d e s
d e f l u i d e s d e c o u p e : les h u i l e s d é c o u p é s i m p l e s , les é m i s n e t t o y e u r s q u i e n l è v e n t les b o u e s s o n t e x p o s é s e n
s i o n s h u i l e d a n s l ' e a u et les s o l u t i o n s a q u e u s e s . L e u r s
p e r m a n e n c e a u c o n t a c t a v e c les h u i l e s d e c o u p e : les
c o n s t i t u a n t s re>pectiN sont é n u m é r é s a u x t a b l e a u x
é c l a h o u s s u r e s el les b r o u i l l a r d s d ' h u i l e s o u i l l e n t la p e u u
1 à 111.
e t les v ê t e m e n t s , d e m ê m e q u e les chifTons i m b i b é s
d ' h u i l e q u e l ' o n m e t d a n s les p o c h e s . E n o u t r e , l o r s q u e
TABl.r.\l
1. C O M P O S I T I O N
UKS
Itlll.KS
DIS
COfPK
les b r o u i l l a r d s d ' h u i l e s o n t p a r t i c u l i è r e m e n t d e n s e s , il
[NSOI.UBLKS ( I I U I . U S »K COCPE SIMPLES)
existe un risque d'inhalation.
D u r a n t la p r e m i è r e m o i t i é d u X X e siècle, le p r o I. Uuse d'huile minérale parafllnique « * 11 naphténique 1 , 60
b l è m e d e r m a t o l o g i q u e le p l u s f r é q u e n t c h e z les m é c a n i à lui» %.
c i e n s é t a i t celui d u b o u l o n d ' h u i l e . D e p u i s l ' a v è n e m e n t
Au-dessous tlt- I0O % huile minérale pure), le fluide de
des lluides de c o u p e à l'eau, qui r e p r é s e n t e n t a u j o u r coup;* esl nu mélange avec des huiles grasses yluiile de
d ' h u i les d e u x t i e r s d u m a r c h é , c ' e s t la d e r m a t i t e eczésaindoux ull de baleine*.
m a t i f o r m e d e c o n t a c t q u i o c c u p e le p r e m i e r r a n g d e s
bactéricides, le cas échéant, pour prévenir le rancissement
m a l a d i e s «le la p e a u d ' o r i g i n e p r o f e s s i o n n e l l e p a r m i ce
1
3. Additifs d'extrême pression :
p e r s o n n e l . L ' a c n é c h l o r i q u e , les k é r a t o s e s , le c a n c e r
a) Miutrc, likire ou eu combinaison avec une huile on une
à c e l l u l e s s q u a m e u s e s e t la m é l a n o s e s o n t é g a l e m e n t
graisse basique, 1 à 3
à m e t t r e au c o m p t e des huiles de coupe.
b) graisses chlorées ot huiles parafflniques, t à 3
c) graisses sulfochlorces, 1 à 3 %.
liuulon
il'huile.
C e t t e alTection s ' a c c o m p a g n e d e
lésions diverses: c o m é d o n s , folliculite et furoncles (voir
1
p l a n c h e en c o u l e u r s , lig. 1H). q u e l ' o n o b s e r v e en
A d d i t i f s q u i ne t i g u r e u l p a s d a n s t o u t e s les p r é p a r a t i o n s .
g é n é r a l à la s u r f a c e d e s m u s c l e s e x t e n s e u r s d e l ' a v a u t b r a s et d e s c u i s s e s , m a i s q u i a p p a r a i s s e n t a u s s i p a r f o i s
TAIII.KAl
I I . C O M P O S I T I O N D K S I I U Î L E S UK C O U I ' K
a u x t e m p e s , à la n u q u e e t à la f a c e d o r s a l e d e s m a i n s ,
S O L I HI.KS ( H l tl.KS
fiMl'I.SIFIABLËS)
c ' e s t - à - d i r e a u x p a r t i e s d u c o r p s e x p o s é e s à la p o l l u t i o n
p a r l'huile ou p a r des v ê l e m e n t s i m p r é g n é s d ' h u i l e . Les
Suivant les applications, le fluide concentré est dilue aver
s u j e t s à la p e a u v e l u e o u g r a s s e s o n t p l u s q u e d ' a u t r e s
prédi>posés au b o u t o n d'huile. L'occlusion des pores
du l'eau dans te rapport de I : f» à 1 : r>0, ft p i t H-'.».
folliculaires, qui précède l ' a p p a r i t i o n des lésions d u
I. Ilinh- minérale, 00 a Cû % du tluide concentré.
b o u t o n d ' h u i l e , e s t d u e à la f o r m a t i o n d e k é r a t i n e en
tjinilsilianis, par exempte, sulfonates de pétrole, savons.
e x c è s , q u e s t i m u l e la r é t e n t i o n d ' h u i l e . L e s r é a c t i o n s
3. Hactéricides tgermicides, antiseptiques, désinfectants), par
i n f l a m m a t o i r e s et p u s t u l e u s e s q u i s e p r o d u i s e n t a u t o u r
exemple, aride crosyliqne, n-phrtiylpliënol, I ris-; hydroxydes follicules p e u v e n t ê t r e b a c t é r i e n n e s ou non. L o r s q u e
métliv I) nilrnmèlhnnc; de 0,1 à 2 % de la concentration
d e s s t a p h y l o c o q u e s p a r t i c i p e n t à la f o l l i c u l i t e , il f a u t
usuelle — recharge suivant les besoins 1 .
y v o i r u n e i n v a s i o n s e c o n d a i r e d o la p e a u e t n o n les
considérer c o m m e des agents pathogènes propres à
4. Antnorrosion (antirouille), par exemple hydroxylainines'.
l'huile de coupe.
5. Additifs d'extrême pression'.
O n . - u p p o s e g é n é r a l e m e n t q u e c e s o n t les b a c t é r i e s
6. Anlimou«»\ pur exempli- silicones'.
p r é s e n t e s d a n s les h u i l e s d e c o u p e q u i p r o d u i ^ r n t la
7. Col'icaiiU, fini- • v-mpl.- tltioreecéinr1.
f o l l i c u l i t e e t les f u r o n c l e s , m a i s c e t t e h y p o t h è s e est
S. Lan
pn-senie dans l'émulsion préparée, ruais également
d é m e n t i e p a r les r e c h e r c h e s b a c t é r i o l o g i q u e s . L ' h u i l e
uti!i>ee pour dissoudre les constituant* solubles dans l'eau.
i n s o l u b l e f r a î c h e e s t s t é r i l e , m a i s la p r é s e n c e d ' e a u -•
a la s u i t e «le p h é n o m è n e s d e c o n d e n s a t i o n s u r les
0. Airenls de conditionnement de l'eau, par exemple polym a c h i n e s , p a r e x e m p l e — f a v o r i s e la s u r v i e e t , d a n s
phosphates, phosphate Irisodique, borax, carbonate de
d e s p r o p o r t i o n s l i m i t é e s , le d é v e l o p p e m e n t d e b a c t é sodium cendre de sonde , quo l'on a j o u t e il l'eau avant h)
ries, g é n é r a l e m e n t (.Irani ' . L e s h u i l e s é m u l s i l l a b l e s
préparation de l'émulsioii '.
e t les f l u i d e s tie r e f r o i d i s s e m e n t s y n t h é t i q u e s s o n t
e u x ai.ssi s t é r i l e s l o r s q u ' i l s s o r t e n t d e f a b r i q u e , m a i s ,
1
A d d i t i f s q u i ne Meurent pu* d u n s loutt-s tes p r é p u r , i t i u n > .
812
Huiles
SI p r è s dilut ion d a n s l e a n e M e n t r é e eu c o n t a c t a v e c
l ' a i r e t les d é c h e t s d i v e r s d u milieu hiimsiin. 011 y p e u t
isoler p l u s i e u r s b a c t é r i e s et c h a m p i g n o n s . Les b a c t é ries q u i p r o d o m i n e n t , les Pneudomnnas,
se r e n c o n t r e n t ,
s o u v e n t en m ê m e t e m p s q u e les e s p i e s
Achromobarter
et Vibrio,
Itaciltus
xubtilis
et Proteus vulgaris.
Ou
o b s e r v e p a r f o i s lu p r é s e n c e d e b a c t é r i e s c o n f o r m e s et
d ' e n t é r o c o q u e s . indice d e p o l l u t i o n fécale, e t , b e a u c o u p
p l u s r a r e m e n t , d e s s t a p h y l o c o q u e s , d e s s a l m o n e l l e s et
»tes shigelles. C ' e s t a v a n t t o u t p o u r e m p ê c h e r la d é c o m p o s i t i o n b a c t é r i e n n e «les hutte»'rie c o u p e et les m a u v a i ses o d e u r s qui l ' a c c o m p a g n e n t «pie 1 ou y a j o u t e d e s
b a c t é r i c i d e s , et n o n p a s p o u r p r é v e n i r les i n f e c t i o n s
d e la p e a u .
P a r a d o x a l e m e n t , les lltiiiles d e c o u p e en s o l u t i o n
a q u e u s e , q u i c o i i l i e n n r n l souvent, d e s b a c t é r i e s , ne. s o n t
p a s g é n é r a l e m e n t associés /i d e s i n f e c t i o n s b a c t é r i e n n e s
d e la p e a u , t a n d i s q u e les h u i l e s insolubles, e x e m p l e s
d e b a c t é r i e s , c a u s e n t d e s folliculites.
Dermatite er:ématiforme
»le contact.
S o u s ses f o r m e s
s u b a i g u ë ou c h r o n i q u e , c e l l e d e r m a t i t e , q u i se m a n i feste par des degrés variables d ' é r y t h è m e , de desquam a t i o n , «le Hssuration et d ' é p a i s s i s s e i n e u t d e la p e a u ,
e s t le p l u s s o u v e n t i m p u t a b l e à l ' e x p o s i t i o n r é p é t é e e t
prolongée à des emulsions dont l'action s ' a p p a r e n t e
S celle d u s a v o n ou à des s o l u t i o n s a q u e u s e s alcalines,
ces d e u x c a t é g o r i e s de s u b s t a n c e s a g i s s a n t c o m m e des
i r r i t a n t s m o d é r é s . A v e c q u e l q u e s - i u i s îles p r o d u i t s les
m o i n s agressifs, il serait p l u s e x a c t d e s u p p o s e r u n e
a t t e i n t e a n t é r i e u r e île la p e a u , ties c r e v a s s e s , p a r
e x e m p l e , d u e s à u n h i v e r sec ou à la m a n i p u l a t i o n de
p r o d u i t s n e t t o y a n t s ou d e s o l v a n t s f o r t s . Ce g e n r e d e
d e r m a t i t e cède* bien s o u v e n t d è s l ' a p p a r i t i o n d e s prem i è r e s c h a l e u r s ou s o u s l ' a c t i o n d ' u n e m o l l i e n t .
P a r m i les c a u s e s d e la d e r m a t i t e e c z é m a t i T o r m e de
c o n t a c t m o i n s c o m m u n é m e n t o b s e r v é e s t i g u r e n t l'irrit a t i o n ou la s e n s i b i l i s a t i o n a u x b a c t é r i c i d e s , a u x prod u i t s a n t i c o r r o s i o n , a u x a d d i t i f s d ' e x t r ê m e pression et
p a r f o i s à l ' h u i l e d e c o u p e e l l e - m ê m e . Kn p r é s e n c e «le
s e n s i b i l i s a n t s ou d ' i r r i t a n t s f o r t s , la d e r m a t i t e est
g é n é r a l e m e n t a i g u ë , a v e c é r v t h è m e . <edème, p a p u l e s
e t vésicules, t.es i r r i t a n t s faibles, tels q u e les d i s t i l l a i s
à b a s p o i n t d ' é b u l l i t ion a n a l o g u e s à l'huile légère
à m a c h i n e et au k é r o s è n e , p r o d u i s e n t plulrtt d e s d e r m a t i t e s s u b a i g u ë s ou c h r o n i q u e s . O n c o m m e t s o u v e n t
l ' e r r e u r d e s u r c h a r g e r les huiles d e c o u p e e n a d d i t i f s
b a c t é r i c i d e s , ce q u i p e u t p r o v o q u e r d e s i r r i t a t i o n s e l
a c c r o î t le r i s q u e d e s e n s i b i l i s a t i o n a u x b a c t é r i c i d e s .
Les sels d e nickel q u i se f o r m e n t lors d e l ' u s i n a g e (les
alliages d e nickel p e u v e n t aussi eut r a i n e r u n e >ensibilisation cutanée.
Acné c h torique.
Le r e c o u r s a u x h u i l e s d e c o u p e
chlorées s'accompagne rarement de manifestations
d'acné chlorique depuis que l'emploi des chloronaphtalènes et des éthers de diphényle en t a n t q u ' a d d i t i f s
d ' e x t r ê m e pression a été a b a n d o n n é . Toutefois, des
a g e n t s p a t h o g è n e s d e l ' a c n é c h l o r i q u e p e u v e n t se
f o r m e r à la f a v e u r d e la d é c o m p o s i t i o n t h e r m i q u e d e s
h u i l e s de c o u p e chlorées.. Ils p r o v o q u e n t u n e m é t a plasie d e s g a n g l i o n s s é b a c é s e t l ' a p p a r i t i o n d e k y s t e s
k é r a t i n o l d e s s u r les p a r t i e s e x p o s é e s ou souillées de la
p e a u . Ces s u b s t a n c e s p e u v e n t aussi ê t r e r e s p o n s a b l e s
d'une atteinte hépatique consécutive à l'absorption
percutanée.
Kératoses et cancer de la peau à cellules
sinuimnises.
Le c a n c e r d e la p e a u a é l é observ e à la s u i l e d u c o n t a c t
a v e c l ' h u i l e d e s c h i s t e d l'.urope, m a i s p a s a v e c l'huile
d e s c h i s l c d ' A m é r i q u e d u .Nord. O u e l q u e s r a r e s c a s do
c a n c e r de la p e a u a t t r i b u é * à l ' a c t i o n îles huiles de
<*0Upe ont éI<• Mirnalés a u C a n a d a el a u x Kl a t s-1'ni*,
m a i s a u H o y a u r n e - 1 ' n i les t r a v a u x p u b l i é s f o n l é t a l
d ' u n e fréquence n e t t e m e n t plus signilicalive, n o t a m m e n t du cancer du s c r o t u m . 1.'atteinte semble affecter
d a v a n t a g e les s e r v a n t s tie t o u r a u t o m a t i q u e à b a r r e s ,
p r i n c i p a l e m e n t les out illeurs e x p o s é s a u x huiles de
c o u p e p u r e s , m a i s les c a s s o n t i n é g a l e m e n t r é p a r t i s
e n t r e les p e r s o n n e s e x p o s é e s a u x r i s q u e s .
d e coupe
Mi'laimse île l'huile.
Assez r a r e , c e t t e p e r t u r b a t i o n
d e ta p i g m e n t a t i o n c u t a n é e se r e n c o n t r e p r i n c i p a l e m e n t chez les m é c a n i c i e n s d ' e t h n i e m é d i t e r r a n é e n n e .
L ' h v p c r p i g t n e u l a l i o n p é r i f o l l i c u l a i r e p e u t r é s u l t e r île
l ' i r r i t a t i o n d i r e c t e p r o v o q u é e p a r u n e huile d e c o u p e
insoluble ou ê t r e s e c o n d a i r e à la folliculite. l.a l i m i t a tion de l ' a t t e i n t e a u x p a r t i e s d é c o u v e r t e s d e la p e a u
donne à penser à une relation avec l'exposition au
r a y o n n e m e n t solaire.
Hist/ues d'atteinte pulmonaire.
Bien q u e l ' e x p o s i t i o n
professionnelle aux brouillards d'huile produits au
c o u r s îles o p é r a t i o n s d ' u s i n a g e soit f r é q u e n t e e t q u ' e l l e
soit s o u v e n t g r a v e , les c a s r a p p o r t é s d e r e t e n t i s s e m e n t
p u l m o n a i r e ( p n e u m o n i e g r a i s s e u s e ) s o n t r a r e s . La
n u i s a n c e et les s y m p l A m e s s u b j e c t i f s ne s o n t p a s
c o n t e s t a b l e s , not a n i m e n t l o r s q u e le b r o u i l l a r d d ' h u i l e
esl visible, c ' e s t - à - d i r e l o r s q u e la c o n c e n t r a i ion d é p a s s e
T» ini;/iu J . A u c u n e c o r r é l a t i o n n ' a é l é é t a b l i e e n t r e
l ' i u h a l a l i o n d e b r o u i l l a r d s d ' h u i l e d e c o u p e e l le c a n c e r
du p o u m o n .
Mesures de sécurité et d'hygiène
P o u r p r é v e n i r le c a n c e r p r o v o q u é p a r les h u i l e s d e
c o u p e , la m e s u r e la p l u s efficace e s t c e r t e s le r e c o u r s
à u n e huile n o n c a n c é r o g è i i e , p a r e x e m p l e à u n e huile
d o n t les c o n s t i t u a n t s c a n c é r o g è n e s o n t é t é é l i m i n é s p a r '
e x t r a c t i o n a u x s o l v a n t s . L ' e n t r e t i e n et d e s règles
strictes d'ordre el de propreté complétées par une
s u r v e i l l a n c e é t r o i t e d u milieu d e t r a v a i l {par e x e m p l e
l'a m é n a g e m e n t d ' é c r a n s p a r e - é c l a b o u s s u r e s , n o t a m m e n t a u x t o u r s a u t o m a t i q u e s à fileter) l i m i t e n t la
c o n t a m i n a t i o n d e l ' o p é r a t e u r e t la p o l l u t i o n d e ses
v ê t e m e n t s . U n s y s t è m e d ' a s p i r a t i o n peuL ê t r e a m é n a g é
p o u r c a p t e r les b r o u i l l a r d s d ' h u i l e et les v a p e u r s
nocives, ( . ' a u t o m a t i s a t i o n p l u s p o u s s é e d e s o p é r a t i o n s
d ' u s i n a g e des m é t a u x e s t a p p e l é e à r é d u i r e e n c o r e
l ' e x p o s i t i o n d u p e r s o n n e l à l ' a c t i o n d e s huiles d e c o u p e .
L o r s q u e le c o n t a c t a v e c ces h u i l e s ne p e u t p a s ê t r e
e m p ê c h é , il f a u t m u n i r les t r a v a i l l e u r s d e v ê t e m e n t s
prolecteurs, et n o t a m m e n t de tabliers imperméables
p o u r p r é s e r v e r la région p u b i e n n e ; d e s c r è m e s i s o l a n t e s
o l é o f u g e s ou h y d r o f u g e s s o n t i n d i q u é e s p o u r t e n i r la
p e a u p r o p r e . Se l a v e r les m a i n s à c h a q u e p a u s e e t les
sécher soigneusement, puis y appliquer une crème
é m o l l i e n t e est u n e m e s u r e d ' h y g i è n e q u i s ' a p p l i q u e
h t o u t e s les s o r t e s d ' e x p o s i t i o n a u x fluides d e c o u p e .
Il esl i n d i s p e n s a b l e q u e le p e r s o n n e l a i t libre a c c è s
à des salles d ' e a u et a u t r e s i n s t a l l a t i o n s s a n i t a i r e s , e t
s o u h a i t a b l e q u ' i l puisse p r e n d r e d e s d o u c h e s . P o u r
l a v e r les m a i n s souillées d ' h u i l e , les p o u d r e s n e t t o y a n tes d o n t le p r i n c i p e actif n ' e s t p a s i r r i t a n t , d e s s a v o n s
aux sulfones e l des produits r é c u r a n t s sans eau sont
d e s m o y e n s efficaces. Il f a u t p r o s c r i r e l ' e m p l o i à c e t t e
fin d e s o l v a n t s p é t r o l i e r s e l d e p o u d r e s ou d e pAtes
a b r a s i v e s . Les c h i f f o n s d e n e t t o y a g e d o i v e n t ê t r e
p r o p r e s e t e x e m p t s de c o p e a u x m é t a l l i q u e s . Les vète^
inejils d e t r a v a i l e t les s o u s - v è t e m e n L s d o i v e n t ê t r e
c h a n g é s au m o i n s d e u x fois p a r s e m a i n e . La p r a t i q u e q u i
c o n s i s t e A g a r d e r les chilTons d a n s les p o c h e s d o i t ê t r e
c o m b a t t u e p a r t o u s les m o y e n s . Des d i s p o s i t i o n s doivent cl re prises p o u r lu lessive d u p e r s o n n e l , lequel «loit
disposer d'un vestiaire c o m m o d e pour changer de
v ê t e m e n t s . Il f a u t p r e n d r e le p l u s g r a n d soin d ' i n s t r u i r e
les t r a v a i l l e u r s de la n é c e s s i t é d ' o b s e r v e r la p l u s s t r i c t e
h y g i è n e corporelle.
I.e> e x a m e n s m é d i c a u x d ' e m b a u c h a g e p e r m e t t e n t
d'écarlp.r de l ' e m p l o i a u x p o s t e s e x p o s é s a u x huiles d e
c o u p e les s u j e t s les plus v u l n é r a b l e s , p a r e x e m p l e les
p o r t e u r s d ' a c n é ( s u r t o u t chez les j e u n e s t r a v a i l l e u r * ' ,
les s u j e t s a t t e i n t s d ' h y p e r k é r a l o s e folliculaire e t t o u s
c e u x d o n t la p e a u m a n i f e s t e u n e i n t o l é r a n c e a u x huiles.
P a r le m o y e n d e s e x a m e n s m é d i c a u x p é r i o d i q u e s ,
ou p e u t s u r v e i l l e r l ' a p p a r i t i o n d e s a l ï c c l i o n s de la p e a u
et j u s t i f i e r la m u t a t i o n à d ' a u t r e s p o s t e s d e s s u j e t s
a t t e i n t s l o r s q u e le t r a i t e m e n t n ' a m é l i o r e p a s leur é t a t .
Vis-à-vis d u r i s q u e d e c a n c e r d u s c r o t u m , il i m p o r t e
d e s u r v e i l l e r les s y m p t ô m e s p r é c o c e s et. d e f a i r e e n
813
Z .
rtutla
de coupe
« Human
engineering
»
s o r l c q u e le p e r s o n n e l soil a v e r t i ilu d a n g e r e t tic la
n é c e s s i t é d e c o n s u l t e r u n m é d e c i n le p l u s l o t p o s s i b l e
a t i n d e n e p a s r e t a r d e r le t r a i t e m e n t
M. M. K E Y ,
USA.
Dermatoses duo (o oil uscil in industry i Itiâfi). Journal of the
American Medical Association, 157, m i l .
•SCHWAFiTZ, L.; T U I . I P A N , L.; U1HMINGHAM, D. J .
(1957). Occupational diseases of the skin. 3rd edition, l.on and
Febiger, Philadelphi;).
• I 1 E N D H I C K S , X. V.; COLL1NGS, G. II.; D O O L E Y , A. [•;.;
GAKKETT, J . T.; HATIIKH, J . U. J r . ,1962). A review of
exposures to oit mist. Archives of Environmental
Health, -i,
13'J.
• K E Y , M. M.; IIITTKU, K. J . ; A K N D T , K. A. (I96fi). CuLting
and grinding lluids anil llu-ir effects on Hit* skirt. American
Industrial Hygiene Association Journal,.'!!, -r.23.
•HODGSON, G. f 1971 ). Dangers d r s luhrilianls pour la pcini.
Hevue d'hygiène du travail, 22, 19.
« H u m a n engineering»
Pym
Expression a n g l o - s a x o n n e intraduisible en français,
d u m o i n s d e f a ç o n c o n c i s e , human engineering
désigne
la c o n c e p t i o n , e n f o n c t i o n d e l ' h o m m e , d e s é q u i p e m e n t s , m a t é r i e l s , a m b i a n c e s e t t e c h n i q u e s . Il s ' a g i t d e
f a i r e e n s o r t e q u e les h o m m e s p u i s s e n t v i v r e e t
travailler d a n s des conditions optimales de sécurité, de
c o n f o r t e t d ' e f f i c a c i t é . L ' e x p r e s s i o n human
engineering
s ' a p p l i q u e a u s s i à la p r o f e s s i o n q u i t r a i t e c e s p r o b l è mes.
Human
engineering
— ou s o n é q u i v a l e n t
human
factors engineering
— e s t en fait usité p r e s q u e exclusivem e n t a u x E t a t s - U n i s . D a n s le r e s t e d u m o n d e , à l ' e x ception p e u t - ê t r e de l ' U R S S où l'on parle p l u t ô t de
p s y c h o l o g i e a p p l i q u é e à la t e c h n i q u e , c e t t e s p é c i a l i s a tion s'appelle ergonomie. L'ergonome, cependant, tend
à s ' o c c u p e r d a v a n t a g e d e la b i o l o g i e e t d e la p h y s i o l o g i e
q u e son h o m o l o g u e a m é r i c a i n . C e t t e d i f f é r e n c e d ' o r i e n t a t i o n provient en partie d ' u n a c c i d e n t historique, eu
p a r t i e aussi du plus g r a n d i n t é r ê t q u e p o r t e l ' e r g o n o m e
a u b i e n - ê t r e s u b j e c t i f d u t r a v a i l l e u r e t à la c h a r g e
énergétique q u e représente son travail. Sans négliger
le c o n f o r t et la s é c u r i t é d e s t r a v a i l l e u r s ,
Vhuman
engineering
e s t p l u t ô t c e n t r é s u r la c o n c e p t i o n d e s
machines et des systèmes de machines et sur l'intégrat i o n d e l ' h o m m e d'ans c e s s y s t è m e s . E n b r e f , l ' e r g o n o m e
e s t p l u s c o n s t a m m e n t s o u c i e u x d e p r o d u c t i o n , le s p é c i a l i s t e e n human engineering,
de produit, Quoi qu'il en
s o i t , e r g o n o m i e e t human engineering
s o n t des disciplin e s p l u s p a r e n t e s q u e d i s s e m b l a b l e s e t , s u r le p l a n
pratique, des c h a m p s d'activité q u e l'on peut tenir
pour é q u i v a l e n t s (-* ERGONOMIE).
C o m m e il a d v i e n t d e m a i n t e s d i s c i p l i n e s t e c h n i q u e s
d ' a u j o u r d ' h u i , d e s n o y a u x p l u s p e t i t s se s o n t c o n s t i t u é s à l ' i n t é r i e u r d u g r o u p e , se s p é c i a l i s a n t d a n s tel o u
tel s e c t e u r plus é t r o i t d u d o m a i n e et s ' a t t r i b u a n t des
dénominations particulières: psychologie expérimentale appliquée, biomécanique, biotechnologie, psychologie a p p l i q u é e à la t e c h n i q u e , t e c h n i q u e s d ' a m b i a n c e ,
t e c h n i q u e s d ' a d a p t a t i o n d e s s c i e n c e s à la v i e , é t u d e
des systèmes homme-machine, psychotechnologie, physiologie d u t r a v a i l . T r a c e r u n e l i g n e d e p a r t a g e e n t r e
ces spécialités n'est p a s chose aisée, et l'on est f o n d é
à c o n s i d é r e r q u ' e l l e s se r a n g e n t t o u t e s s o u s la r u b r i q u e
plus générale et globale de ï'/iumo/i
engineering.
OhJeetIN
Q u o i q u e la s é c u r i t é d u t r a v a i l e t , p a r c o n s é q u e n t , la
réduction du n o m b r e des accidents soient des objectifs
m a j e u r s d e c e t t e d i s c i p l i n e , ce n e s o n t p a s les s e u l s .
E l l e c o m p o r t e a u s s i , et e s s e n t i e l l e m e n t , l ' é t u d e d e s
m o y e n s d ' e x p l o i t e r les m a c h i n e s a v e c u n e p l u s g r a n d e
814
e f f i c a c i t é , la r e c h e r c h e d ' u n e p l u s g r a n d e p r o d u c t i v i t é
des o p é r a t i o n s et des systèmes, d ' u n e r é d u c t i o n de
l'elTort h u m a i n n é c e s s a i r e à l ' e x p l o i t a t i o n d e s m a c h i n e s
et d ' u n p l u s g r a n d c o n f o r t île l ' h o m m e i n t é g r é d a n s
les s y s t è m e s h o m m e - m a c h i n e .
P o u r a t t e i n d r e c e s o b j e c t i f s , I 'human
engineering
p e u t m e l t r e en j e u d e s m é t h o d e s , d e s d o n n é e s e t d e s
principes qui ressorlissent à m a i n t e s a u t r e s disciplines,
scient i l l q u c s o u t e c h n i q u e s , t e l l e s q u e la b i o l o g i e ,
l ' e n s e i g n e m e n t , l ' u r t d e l ' i n g é n i e u r , la m é d e c i n e , l ' a n t h r o p o l o g i e p h y s i q u e , la p h y s i o l o g i e , la p s y c h o l o g i e ,
la s o c i o l o g i e e t la t o x i c o l o g i e .
L e s p ô l e s m a j e u r s tic c e t t e a c t i v i t é s o n t d o n c la
r e c h e r c h e f o n d a m e n t a l e et a p p l i q u é e , c o n c e n t r é e s u r
les p e r f o r m a n c e s h u m a i n e s , a f i n d e d é v e l o p p e r d e s
c o n n a i s s a n c e s n o u v e l l e s , e t l ' a p p l i c a t i o n d e ces c o n n a i s s a n c e s à la c o n c e p t i o n e t à l ' é v a l u a t i o n d e s s y s lènies.
Méthodes de r e c h e r c h e
D a n s ses t r a v a u x d e r e c h e r c h e , le s p é c i a l i s t e e n
human engineering
u t i l i s e b i e n s o u v e n t les t e c h n i q u e s
c l a s s i q u e s d e l a b o r a t o i r e e n h o n n e u r d a n s les s c i e n c e s
h u m a i n e s e t la b i o l o g i e . Il lui a f a l l u a u s s i e m p r u n t e r
certaines m é t h o d e s à d ' a u t r e s disciplines et en imaginer
d ' o r i g i n a l e s p o u r d é b r o u i l l e r les p r o b l è m e s c o m p l e x e s
de l ' h o m m e au travail. Q u e l q u e s - u n e s d e ces m é t h o d e s
sont évoquées ci-après.
Méthode de l'incident
critique.
Les é t u d e s faites sur
les a c c i d e n t s o u les « q u a s i - a c c i d e n t s » q u i se s o n t c o n c e n t r é e s s u r la r e c h e r c h e d e l ' i n c i d e n t c r i t i q u e o n t é t é
particulièrement révélatrices de situations propices
a u x d é f a i l l a n c e s e t i n d i c a t i v e s d e s p r o b l è m e s d o n t la
solution appelle des méthodes de recherche plus rafllnées.
Méthodes d'observation.
Vhuman
engineering
appliq u e n o m b r e d e c e s m é t h o d e s , n o t a m m e n t celles q u ' i l
e m p r u n t e à l'ingénieur de production pour l'étude de
l ' h o m m e au travail. L'étude du poste échantillon,
l'analyse fonctionnelle et l'analyse du cycle de production s'inscrivent sons cette r u b r i q u e .
Méthode
des modèles.
La c o m p l e x i t é des s y s t è m e s
d e m a c h i n e s a v e c l e s q u e l s il e s t le p l u s s o u v e n t a u x
[irises o b l i g e ce s p é c i a l i s t e à t i r e r le m a x i m u m d ' i n f o r m a t i o n s des diverses techniques de simulation: simulateurs, mannequins, matériel didactique, modèles de
toute sorte.
Le s i m u l a t e u r j o u e u n r ô l e d a n s u n e i n f i n i t é d e
r e c h e r c h e s . La r e c o n s t i t u t i o n l i d è l e d ' u n s y s t è m e c o m p l e x e d ' o p é r a t i o n s c o n f è r e à l ' o b j e t d e l ' é t u d e le
réalisme qui favorise l'extrapolation des résultats de
laboratoire. Un s i m u l a t e u r r e v i e n t en général moins
c h e r q u e le s y s t è m e q u ' i l r e p r o d u i t , p e r m e t t a n t à
m o i n d r e s f r a i s u n e r e c h e r c h e n é a n m o i n s c o n c r è t e . Il
est é g a l e m e n t possible de t r a v a i l l e r s u r m a q u e t t e ou
s u r m o d è l e a v a n t q u e le s y s t è m e s o i t r é a l i s é e n
g r a n d e u r , ce q u i p e r m e t a u s p é c i a l i s t e d e p a r a c h e v e r
ses r e c h e r c h e s e u t e m p s u t i l e , d e s o r t e q u e l ' o n p u i s s e
t e n i r c o m p t e d e ses c o n c l u s i o n s a v a n t q u e le s y s t è m e
a i t Lrouvé sa f o r m e d é f i n i t i v e . C e r t e s , la s i m u l a t i o n
reste un a r l a u t a n t q u ' u n e science, mais certains
principes, issus de s i m u l a t i o n s bien c o n d u i t e s , constit u e n t peu à peu u n e s o m m e de connaissances utiles.
Hapports subjectifs.
Enfin, maintes techniques sont
appliquées au rassemblement d'échantillons représentatifs de l'opinion des o p é r a t e u r s aussi bien q u e des
u t i l i s a t e u r s . Elles v o n t d e l ' e n t r e t i e n s i m p l e , n o n
s t r u c t u r é , a u x échelles de classement, analyses psvehophysiques et autres i n s t r u m e n t s de mesure des plus
s o p h i s t i q u é s , eu p a s s a n t p a r les q u e s t i o n n a i r e s s u r é l u borés.
Chump d'application
A u x E t a t s - U n i s , o n t r o u v e d e s s p é c i a l i s t e s d e Vhunum engineering
dans n o m b r e d'administrations publiq u e s et d ' o r g a n i s m e s o f f i c i e l s , d a n s p l u s i e u r s d o u z a i n e s
have not been included w i t h most medical reports ol
graphite pneumoconioses.
SAFETY AND HEALTH
MEASURES
Present data strongly indicate that both natural and
manufactured graphite dust concentrations should be
controlled to the threshold limit value. Most, if not a\\
natural graphite ores contain crystalline silica and
silicates The amount and type of impurities determine, in
cart the potential hazard associated w i t h inhalation of
the dust It is therefore essential that periodic analyses
are made of the raw ore and airborne dust for crystalline
silica and silicates, w i t h special attention to feldspar talc
and mica Acceptable dust levels must be adjusted to
accommodate the effect these disease-potentiating
dusts may have on the health of the workers.
Graphite pneumoconiosis is progressive even after the
worker has been removed from the contaminated
environment. Workers may remain asymptomatic during
many years of exposure and disability often comes
suddenly
Prevention of the disease is. therefore,
essential Engineering controls, w e t drilling, exhaust
ventilation, remote handling, etc.. are recommended.
W h e r e effective engineering controls are not possible,
workers should wear respiratory protective equipment
approved for use against pneumocomosis-producing
w e l d i n g of metal to tool point, loss of hardness of the
tool point, and distortion of the workpiece. Grinding is a
kind of cutting in w h i c h metal is removed by a grinding
wheel, containing abrasive grains that act as miniature
cutters.
. . .
.
Cutting and grinding fluids, also k n o w n as lubricoolants. have t w o primary functions:
As in all industries, an employee health maintenance
programme must consider all environmental conditions
associated w i t h the job. In the mining of natural graphite,
this may include noise generated by drills, excavating
equipment, ore crushing and processing. Explosive
chemicals and their decomposition products, carbon
monoxide, nitrogen oxides, etc.. may. if not controlled,
result in excessive worker exposure. Graphite purification utilises hydrofluoric acid and sodium hydroxide. In
addition to the corrosive action of both chemicals,
overexposure to fluorides can result in serious disease
Worker protection from physical hazards is an essential
part of any health programme.
P E N D E R G R A S S . J. A.
Pneumoconiosis:
CIS 76-953 "Pneumoconiosis in graphite curers". Uragoda.
C G • Rajendra M Indian Journal of Industrial
Medicine
(Calcutta), July 1975. 21/3 (105-113). 14 ref.
'Pneumoconiosis in persons engaged in the production of
carbon electrodes' (Pylica plue u zatrudmonych przy
orodukcii elektrod weglowych). Zahorski. W.: PotoskaSkowronek Z.; Pierzchala. W. Medycyna Pracy (Lodz).
1975. 26/1 (1-8). 12 ref. (In Polish)
Experimental
pathology:
CIS 74-1574 "Contribution to the study of the biological effects
of coke and graphite" (Zur biologischen Schàdigungsmoglichkeit durch die Kohlenstoffmodifikationen Koks und
Graphit). Einbrodt. H. J. Staub (Dusseldorf). Dec. 197J. JJ/
12 (474-478). 45 ref. (In German)
Industrial hygiene:
CIS 81 -669 Dust collection in plants manufacturing
electrodes
and artificial graphite (Obespylivanie na èlektrodnyh i
èlektrougol'nyh zadovah). Koptev. D.V. (Moscow. Izdatel stvo "Metallurgija", 1980). 127 p. lllus. 63 ref. (In Russian)
G rinding and catting fluids
In metal-cutting machine tools, a hardened tool edge
removes chips by different mechanical means, such as
turning planing, shaping, drilling, milling, boring and
broaching. M o s t of the work performed in metal-cutting
is translated into heat, which, if not dissipated, can cause
(a)
to cool the workpiece and tool, thus preventing
heat damage; and
(b)
to lubricate, thus reducing frictional heat and the
chip-tool interface and between the tool and the
freshly cut surface.
Secondary functions are to flush away chips and swarf,
reduce strain hardening of the machined metal, and
protect the workpiece against rusting. On high-speed
machines, such as automatic lathes, considerable
quantities of these fluids may be needed.
Types of fluid. The three basic types of cutting and
grinding fluids are: straight cutting oils; oil-in-water
emulsions and aqueous solutions. Their ingredients are
listed in tables 1, 2 and 3.
Table 1.
Composition of straight cutting oils (insoluble oils)
1
Paraffinic or naphthenic mineral oils 60-100%.
Sometimes blended with vegetable or animal oils.
2
Extreme pressure (EP) additives
(a) Sulphur-free or combined with base oil or tats
(b) Chlorinated fats and paraffin oils. 1 -3%
(c) Sulphochlorinated fats. 1-3%
Biocides, sometimes added to prevent rancidity.
3.
Table 2.
Composition of soluble oils (water-miscible oils or
emulsions)
.
Depending on intended use. concentrate is diluted with water
at a rate of between 1 : 5 and 1 : 50: pH 8.0-9,5.
1. Mineral-oil 60-85% of concentrate.
2. Emulsifiers. for example, petroleum sulphonates, soaps,
non-ionic surfactants.
•3 Biocides-thiocarbamates. phenols, adamantane salts,
isothiazolinones. nitromorpholine. fn's-(hydroxymethyl)
nitromethane. triazines. pyridinethiol-l-oxide.
4. Corrosion inhibitors, for example alkanolamines.
•5. Extreme pressure (EP) additives.
6. Antifoaming agents, for example silicones.
7. Dyes, for example fluorescein, petroleum azo dyes.
8 Water conditioners, for example polyphosphates,
trisodium phosphate, borax, sodium carbonate (soda
ash). Sometimes added to water before formation of
emulsion.
• Present in premium soluble oils (emulsitiable concentrates).
HAZARDS
Slippery floors caused by oil thrown off from machine
tools can considerably increase the likelihood of falls,
which, if they occur in the proximity of fast-running
machinery, may have very serious results. However.'the
main hazards are those w h i c h affect th*; machinn
operator's health. The hands and arms ol machine
operators, tool setters and swarf removers are constantly
exposed to cutting oils: splashes and mist contaminate
skin and clothing and saturated w i p i n g rags are kept in
pockets. W h e r e large quantities of mist are formed there
may be an inhalation hazard.
979
rùOie 3
C o m p o s i t i o n of s y n t h e t i c a n d s e m i - s y n t h e t i c c u t ting fluids
A c u t t i n g f l u i d c o n c e n t r a t e w h i c h c o n t a i n s little or n o oils.
T h e c o n c e n t r a t e is d i l u t e d at a rate of b e t w e e n 1 : 1 0 a n d
1 : 2 0 0 . d e p e n d i n g o n i n t e n d e d use: p H 8 - 1 0 .
1.
O i l s : 5 to 3 0 % in s e m i - s y n t h e t i c f l u i d s : n o n e in
synthetic fluids.
2.
C o r r o s i o n i n h i b i t o r s , for e x a m p l e a l k a n o l a m i n e s .
c a r b o x y l i c acids, m e r c a p t o b e n z o t h i a z o l e s , b o r a t e esters.
3.
A n i o n i c a n d n o n - i o n i c s u r f a c t a n t s , for e x a m p l e soaps,
s u l p h o n a t e s . e t h o x y l a t e d a l c o h o l s or p h e n o l s .
*4.
B l e n d i n g a g e n t s , for e x a m p l e g l y c o l s .
'5.
Biocides.
*6.
Water c o n d i t i o n e r s , tor e x a m p l e E D T A . b o r a t e s a n d
phosphates.
*7.
A n u f o a m i n g a g e n t , for e x a m p l e s i l i c o n e s .
•8.
Dyes.
' Additives not present in all formulations.
During the first half of the 20th century, the most
common cutaneous problem of machinists was oil acne.
However, with the increasing use of water-base cutting
and grinding fluids, which account for about two-thirds
of the market, eczematous contact dermatitis has
become the most common occupational skin disease of
machinists. Chloracne. keratoses, squamous cell cancer
and melanosis can also be caused by cutting oil
exposure.
Oil acne. In oil acne a variety of lesions may be
seen-comedones, folliculitis and furuncles. The lesions
usually occur on the extensor surfaces of the forearms
and thighs, but are sometimes seen on the temples, nape,
and backs of the hands, i.e. areas contaminated by oil or
oil-soaked clothing and infrequently washed. Individuals with hairy or oily skin have a greater tendency
to develop oil acne. Occlusion of the follicular orifice, the
antecedent of the lesions of oil acne, is caused by
overgrowth of keratin, which is stimulated by retention
of oil. Inflammatory and pustular reactions which occur
around the follicles may or may not contain bacteria.
When staphylococci contribute to the folliculitis, they
should be regarded as secondary invaders from the skin
and not as pathogens from the cutting oil.
It is generally.supposed that bacteria present in cutting
fluids cause folliculitis and furuncles, but this is contrary
to bacteriologic evidence. Fresh insoluble oil is sterile,
but the presence of water, such ascondensation from the
machines, will allow survival and limited growth of
bacteria, usually Gram-negative. Emulsifiable oil and
synthetic coolants are also sterile when manufactured;
but after they are diluted with water and come in contact
with air and human refuse, a variety of bacteria and fungi
can be isolated. The predominant bacteria, pseudomonads. are frequently found in association with
Achromobacterand
Vibrio species. Bacillus subtilis. and
Proteus vulgaris. Coliform bacteria and enterococci,
indications of faecal pollution, are occasionally found.
Pathogenic Staphylococcus.
Salmonella and Shigella
species are found only rarely. Biocides are added to
soluble oils and semi-synthetic and synthetic coolants
primarily to prevent bacterial decomposition and the
formation of odours, and not for prevention of skin
infections
Paradoxically, the water-base lubricoolants, which
frequently contain bacteria, are not usually associated
with bacterial infections of the skin, whereas the
insoluble oils, which are relatively free of bacteria, are
associated with folliculitis.
980
Chloracne. Chloracne is a severe form of occupational
acne caused by exposure to certain highly toxic
halogenated aromatic chemicals (naphthalenes, biphenyls, dibenzofurans, dibenzo-p-dioxins and chlorobenzenes). Chloracne from cutting oils is seldom seen
because of the elimination of chloronaphthalenes and
biphenyls as extreme pressure additives. However,
chloracnegens may. in rare cases, be formed during
thermal decomposition of chlorinated cutting oils.
Chloracnegenic chemicals cause metaplasia of sebaceous glands with the production of keratinous cysts on
exposed or contaminated skin. Comedones, papulésand
pustules may also occur. Although chloracne represents
one of the most sensitive indicators of biological
exposure to these chemicals, systemic toxicity may also
occur, especially liver damage, hyperlipidaemia and
nervous system disturbances.
4
Eczematous contact dermatitis. Subacute and chronic
eczematous contact dermatitis, manifested by varying
degrees of erythema, scaling, fissuring and thickening of
the skin, is usually attributed to repeated and prolonged
exposures to emulsions with soap-like action and/or to
alkaline aqueous solutions, both of which can act as
low-grade irritants. With some of the milder products it
would probably be more accurate to presuppose
previous damage to the skin such as chapping due to low
humidity in winter or use of harsh cleaners or solvents.
Often this type of dermatitis will clear after the onset of
warm weather or the use of an emollient.
Less common causes of eczematous contact der- i I
matitis are irritation from and sensitisation to bac- 1
tericides. corrosion inhibitors, extreme pressure oil
additives, and sometimes the oil itself. When sensitisers
and strong irritants are involved, the dermatitis is usually
acute, with erythema, oedema, papules and vesicles.
Low-grade irritants, such as low-boiling distillates
similar to light machine oil and kerosene, tend to produce
subacute or chronic dermatitis. As the boiling point
increases skin irritance may lessen. A common mistake in
the maintenance of an emulsion-type cutting fluid is the
addition of biocide in excess of that necessary to prevent
bacterial growth. Excess biocide can be irritating, and the
likelihood of sensitisation is increased.
Although said to be rare, cases of allergic contact
dermatitis to cutting fluid additives, breakdown products
or metal salts (nickel, chromium or cobalt) are often
overlooked.
Allergic contact dermatitis from the following additives has recently been reported: ethylenediamine.
butylphenol (antioxidant), chlorocresol, fr/s-nitrol and
triazine (antimicrobials), hydrazine (stabiliser), balsam
of Peru (fragrance), and Proxel CRL (benzisothiazolin3-one).
The diagnosis of allergic contact dermatitis requires
accurate performance and interpretation of patch tests to
the fluid itself and to individual additives. This procedure
should only be performed by a physician experienced
with this test. The confidential nature of most fluid
formulati ons makes such testing extremely difficult to
perform accurately. Dilution of the sensitising chemical
additive in the final cutting fluid formulation may
obscure identification of the specific allergen. "
Photosensitivity may occur from certain wavelengths
of artificial light which react with the skin and/or
chemicals in contact with the skin producing eczema un
exposed body areas. Photoallergy contact dermatitis
may rarely occur from halogenated salicylanilides.
phenothiazmes, or certain fragrances added to cuttinq
fluids.
Keratoses and squamous cell skin cancer. Cutaneous
neoplasia has occurred from contact with European
Grtading
shale oil. but not from North American shale oil. Few
cutaneous cancers fro,m cutting oil exposures have been
reported in Canada and the United States, but studies in
the United Kingdom have s h o w n a significant incidence,
especially of cancer of the scrotum. The incidence
appears to be greatest in automatic bar lathe workers and
especially among setters and setter operators exposed to
neat cutting oils, but cases are unevenly distributed
among the persons at risk.
Oil melanosis.
This rare pigmentary disorder is seen
primarily in machinists of Mediterranean origin. The
perifollicular hyperpigmentation may result from direct
irritation caused by the insoluble cutting oil. or it may be
secondary to folliculitis. Limitation of the pigmentation
to exposed areas indicates a relationship to sun
exposure.
Granulomas.
Granulomas are chronic, indolent, focal
inflammations w h i c h tend to heal w i t h scarring. Foreign
body granulomas may develop after penetration of
metallic swarf or splinters.. Granulomas may develop
from beryllium alloys, and oil granulomas may develop
from grease and oil gun injuries.
Pulmonary
hazards. A l t h o u g h occupational exposures
to oil mists generated during cutting operations have
been numerous and frequently heavy, reported cases of
respiratory system disorders (lipid pneumonia) have
been rare. Nuisance and subjective complaints do occur,
however, especially w h e n the oil mist is visible (i.e. at
concentrations greater than 5 m g / m 3 ) . N o relationship
has been established between inhalation of oil mist and
lung cancer although warnings have been issued against
cutting fluids containing nitrites and secondary or
tertiary amine additives because of the formation of
carcinogenic nitrosamines. Also it w o u l d seem prudent
to limit exposure to aromatic base oils. Some European
countries, such as the United Kingdom; allow only low
(i.e. less than 10%) aromatic oils to be used in straight
cutting oils as well as water-miscible cutting fluids. It
should be noted that high concentrations of oil mist are
also dangerous from the safety point of view. Flash fires
have occurred from general contamination of the work
area.
SAFETY AND HEALTH
and cutting
fluids
Further reduction in contact exposure can be expected
from increased automation of metal-cutting operations.
W h e n contact cannot be avoided, protective clothing,
including impervious aprons to protect the groin, and
arm protection such as sleeves should be w o r n if not a
safety hazard (gloves are generally considered a safety
hazard and should not be w o r n ) ; barrier creams of the
oil- or water-repellent type are helpful in keeping the skin
clean (amine-containing creams may react to form
nitrosamines in the presence of nitrites). Cleansing
soiled skin at work breaks followed by thorough drying
and the application of an emollient cream is a hygienic
procedure applicable to all types of lubricoolant exposures. Suitable and readily accessible washing and
sanitary facilities are essential: shower baths are
desirable. For removing oil. p o w d e r e d cleansers containing a non-irritating scrubber, sulphonated oil soaps and
waterless skin cleansers are effective. The use of
petroleum solvents and abrasive cleaners for cleaning
the skin should be avoided. W i p i n g rags and waste
should be clean and free of metal chips. W o r k clothing
and underwear should be changed daily. The practice of
. keeping wipers in trouser pockets should be discouraged
in every way. There should be routine arrangements for
laundering and good changing room accommodation.
The workers should be thoroughly instructed in the need
for scrupulous personal hygiene.
Pre-employment medical examination will serve to
exclude from exposure those persons most likely to be
affected, for example acne sufferers (especially young
persons), persons w i t h follicular hyperkeratosis, those
showing any skin intolerance to oil and those w i t h
eczematous dermatitis of the hands.
Periodical medical examination will serve to control
the development of skin affections and enable sufferers
to be transferred to other w o r k w h e n the condition fails
to respond to treatment.
In dealing w i t h the risk of scrotal cancer, it is important
to w a t c h for early symptoms and it should be ensured
that workers are aware of the dangers and of the
necessity of seeking early advice and treatment.
KEY, M . M .
T A Y L O R . J. S.
Y A N G . C.
MEASURES
In the prevention of cancer due to cutting oils, the most
effective measure is the use of non-carcinogenic oil, for
example cutting oil from w h i c h the carcinogens have
been removed by solvent extraction.
Environmental control measures should include:
(a)
careful identification, by generic name,
ingredients in the cutting fluid used;
of
all
(b)
programmes to keep the coolants free of tramp oil.
foreign particles, and dirt through the use of
effective filters and redesigning the coolant flow
system to eliminate "eddies" and "backwaters" of
coolant;
(c)
daily programmes to monitor coolant characteristics. such as pH. bacteria count, etc.;
(d)
daily programmes, such as hosing d o w n , to keep
machinery clean;
(e)
redesigning spray application to minimise coolant
splash and spray;
(f)
using splash goggles and curtains;
(g)
use of local exhaust systems and oil collectors to
reduce airborne oil mist.
"Manufacturing exposure to coolant-lubricants". Welter. E. S.
Journal of Occupational Medicine (Chicaqo) AUQ 1978
20/8 (535-538). 8 ref.
"Dermatoses associated w i t h metal-working fluids". Taylor
J. S. Proceedings. Second International
Conference: Lubrication Challenges in Metal-working
and Processing
(Chicago. Illinois Institute of Technology Research 1979)
239 p.
"Bacteria and soluble oil dermatitis". Rycroft. R. J. G. Contact
Dermatitis (Copenhagen). Jan. 1980. 6/1 (7-9). 4 ref.
"Allergic contact sensitization to Epoxide 7 in grinding oil".
Rycroft. R . J . G . Contact Dermatitis (Copenhagen) A u a ~
1980. 6/5 (316-320). 2 ref.
CIS 80-111 "Allergic skin reactions in metal machining shops"
(Allergische Hautschaden bei der Metallbearbeitung). Ippen
H. Dermatosen in Beruf und Umwelt (Aulendorf) 1979 27/
3 ( 7 1 - 7 4 ) . Illus. 28 ref. (In German)
Nitrosamines in cutting fluids. Current intelligence) hullntln
No. 15. (National Institute for Occupational Safety and
Health. 4676 Columbia Parkway. Cincinnati) (6 Oct 1978)
4 p.
CIS 79-532 Control of exposure to metalworking
fluids
O^Brien. D.; Frede. J. C. DHEW (NIOSH) publication No. 78165 (National Institute for Occupational Safety and Health
4676 Columbia Parkway. Cincinnati) (Feb 1978) 36 p'
17 ref.
981
National
Safety
Council
Cutting Oils, Emulsions,
and Drawing Compounds
T H I S DATA S H E E T discusses cutting oils, emulsions, and drawing
pastes or compounds that are used
in metal cutting and drawing processes.* Emphasis is placed on
those skin irritations (dermatoses)
sometimes caused by exposure to
such coolants and lubricants.
Methods of preventing these skin
disorders and recommended hygienic practices are covered.
Uses
2. Cutting oils, emulsions (also
called lubricants or coolants), and
drawing pastes or compounds are
used in metal cutting and drawing
processes for these purposes:
a. To cool the cutting tool'and
the work.
b. To reduce friction between
tool, chip, and work.
c. To produce a smooth finish on
the work.
d. To flush out the cutting area
and wash away chips.
e. To protect the finished work
from rust and corrosion.
Types
3. Cutting oils may be of animal,
vegetable, or mineral origin; frequently, they are a mixture. They
may be classified as either soluble
or insoluble. The soluble cutting
oils usually contain mineral oil,
• This data sheet replaces data sheet
1-501, which was discontinued.
EDITOR'S NOTE: Normally, data sheets
are available ll/2 months after appearing in N S H N R W S : '
soap, and a preservative component such as cresol, phenol, glycol,
alcohol, or nitrobenzene. They are
used primarily as coolants and
secondarily as lubricants.
4. Insoluble cutting oils usually
consist of fatty oils such as lard oil
and petroleum oil or a combination of the two. They may be sulfurized with free or combined sulfur, or they may be chlorinated or
sulfochlorinated. They may contain an inhibitor that generally is
one of the amines. They are used
primarily as lubricants.
Physiological aspects
5. Cutting oils and compounds
are frequently blamed for almost
every kind of skin disorder that
occurs among metal workers using them. Generally, however, cutting oils and compounds become a
source of skin trouble chiefly after
they have become contaminated
through poor personal hygiene
habits on the part of the workers
(such as spitting into the coolant)
or through contact with machine
parts or other items in the working environment. When infection
occurs, it is usually secondary.
6. The following are primary effects that cutting oils may have on
the skin:
a. Mechanical plugging of the
pores may occur, with resultant
formation of comedomes or blackheads.
b. Defatting action may cause
drying and cracking of the skin, so
Data Sheet
1-719-86
that it becomes more subject to
abrasions or secondary infections.
c. If metal slivers in used cutting oil or in soiled wiping cloths
or toweling become inbedded in
the skin, secondary infections may
result.
d. Some sulfur, chlorine, or
other additives may be present in
sufficient amounts to cause skin
irritation or sensitization. Chlorinated aromatic organic compounds may cause chloracne, but
chlorinated paraffins and paraffinic materials are relatively free
from systemic or dermatological
effects.
e. Inhibitors (germacides), although generally not present in
primary irritant quantities, may
act as sensitizers.
f. Some cutting oils have been
suspected of being capable of
causing premalignant skin lesions.
7. When there is excessive or
prolonged exposure to contaminated cutting oils and good hygiene is not practiced, several
types of dermatitisjcan develop: oil
acne or folliculitis; oil dermatitis,
cracking of the skin with resultant
infections, skin pigmentation, and
chloracne.
Oil acne or folliculitis
8. Oil acne or eczema-like inflammations are the most common
forms of dermatitis affecting machinists and other workers exposed to contact with cuting oils
and emulsions. As might be expected, the skin exposed on portions of the forearms is most frequently affacted.
9. In mild, cases, the skin is
o
'•V 0 ^(-^jv \ -v . - . e. •• •«•
^^
MARCH
NATIONAL tAFWTT ANO HIALTN NSWS
74
marked with numerous blackheads and inflamed spots. In more
severe cases, these red spots or
blotches turn into pimples, which
become boils or festering sores.
Sometimes these pimples and boils
also occur on the legs, thighs, and
other parts of the body in contact
with oil-soaked clothing. The exact reasons for these manifestations are not entirely understood,
but it is believed that the pores in
the skin are either blocked or contaminated so t h a t they cannot
function normally.
10. Contact with the oil does not
have the same effect on all workers. Many appear to be altogether
immune and never experience the
slightest irritation. Some people
may work on cutting operations
for years with only an occasional
irritation. Some will get the blackheads on their arms, but not the
pimples. Normally, the arms become covered w i t h blackheads
within a few weeks after contact
with oil, and in a comparatively
short time numerous pimples and
boils appear on the exposed skin
surface.
11. These differences in susceptibility are largely due to variations in personal cleanliness and in
skin-resistance. Persons who have
excessively dry skin, which easily
becomes chapped and cracked, are
susceptible to dermatitis resulting
from the defatting action of mineral oils. A number of medical authorities have also pointed out that
light-skinned persons are more
susceptible to cutting oil dermatitis than are dark-skinned persons.
12. Dark, hairy, and oily skin,
though better able to withstand
the action of solvents, is predisposed to the development of oil
acne. This type of skin has highly
active sebaceous or oil glands, and
the numerous hair follicles provide
settling points for c u t t i n g oils
making removal of such cutting oil
difficult.
Oil dermatitis
13. A c e r t a i n percentage of
workers may develop an inflammation of the skin, i t is characterized by redness and swelling and
may result from:
a. Continuous exposure to moisture.
h. T h e a l k a l i n i t y of the emulsion.
c. An excessive amount of germacide in the oil.
d. An allergy to some ingredient
in the oil or emulsion.
14. I f the o f f e n d i n g agent is
found to affect a number of employees, consideration should be
given to removing the material.
On the other hand, if only a few
employees are affected, consideration should be given to placing the
employees on a job where they
would not come in contact with the
oil.
though these germs are on the
skin of everyone most of the time,
they o r d i n a r i l y 3o no harm because they cannot p e n e t r a t e a
healthy, unbroken skin. Only when
the skin becomes
inflamed,
scratched, or broken can they
cause infection.
w,^ -TV , -^-v m ^
Warts or premallgnant
skin lesions
18. F l a t w a r t y - l i k e growths
somewhat similar to callouses may
occur on the skin areas frequently
in contact with mineral oils. These
growths rarely cause trouble or
even discomfort.
Infections
Hygienic practices
15. A highly important factor in
the development of skin troubles
in cutting machine operators is the
mechanical injury caused by metal
chips and particles. When a deep,
heavy cut is made on metal, hot
chips with sharp ragged edges fly
off and frequently strike the hands
and arms of the operator, cutting
the skin and leaving openings for
bacteria. In lighter cutting, numerous fine particles of metal are
taken up and carried by the oil to
the w o r k e r ' s hands and arms,
expecially when the oil is used
over and over without being filtered.
Mi. If iiie skin is rubbed (for instance, the skin between the fingers) or if the operator wipes the
oil from his arms and hands with a
rag or piece of cotton waste — a
common practice — these particles scratch the skin and make
many small openings that will permit bacteria to get into the tissues
and cause infection. I t should be
emphasized that it is not just the
bacteria present in the cutting oi!
that causes dermatitis. Defattini:
of the skin so that the skin crack
open or scratching with metal particles allows bacteria to penetrate,
causing infection.
17. Two types of germs capable
of causing infection,
streptococci
and staphylococci,
are normally
present on the skin.
Streptococci
are harbored in protected skin
crevices. They are rarely found in
oil dermatitis, although they may
act as secondary agents. Staphylococci are much more prevalent
on the skin and constitute the primary infective organisms. Al-
19. Employees should be thoroughly trained in the hygienic
practices described in the following paragraphs, and supervisors
should maintain a constant check
to see that these practices are observed.
20. The importance of personal
cleanliness as a means of preventing skin troubles from cutting oils
and compounds cannot be overemphasized. By regular and thorough cleansing of the hands and
arms w i t h soap and w a t e r , employees can reduce accumulations
of oil and dirt in the pores of the
skin. Such cleansing also will help
to remove germa that may be on
the skin.
21. Proper washing facilities
with plenty of water, soap, and
towels should be provided in convenient locations. Workers should
not be p e r m i t t e d to rinse their
arms in solvent before washing.
22. Normal washing (three to'
four times daily) seldom causes
dermatitis, but workers employed
in occupations where the hands
are soiled continually may develop
dermatitis if hand washing with
soaps is frequent (10 to 20 times a
day).
23. Workplace soaps also have
been designed to remove oil,
grease, and other stains not readily removed by o r d i n a r y soaps.
Waterless hand cleansers contain
15 to 20 per cent solvent (usually
a petroleum distillate). They are
not truly "waterless," because the
solvent is formulated in a waterbased cream w i t h a mild detergent action.
75
surfaces usually is accomplished
with an anionic synthetic detergent, the alkalinity of which is
substantially greater than deterg e n t s marketed for use on the
skin.
28. These products usually are
mixed and diluted in hot waterprior to use. Inadvertent skin contact may occur during the preparation or use of the d e t e r g e n t ,
particularly if water-proof gloves
are not worn. Skin contact with
the concentrate increases the risk
of dermatitis.
29. The temperature of the wash
solution increases the chemical activity of the detergent and will elevate skin surface t e m p e r a t u r e
when contacted, promoting skin
penetration of d e t e r g e n t chemicals, and f u r t h e r increasing the
risk of dermatitis.
30. Detergents used for disinfecting hard surfaces may contain
a variety of germicidal agents, but
phenolic derivatives are the most
common. In addition to their substantial skin irritating potential,
phenolic germicidals also may sen-
24. Like any petroleum solvent,
these products may cause dermatitis if used excessively during the
work day. They remove oil and
grease stains reasonably well from
most skin s u r f a c e s except the
palms, where skin creases make
the stains less accessible to cleaning. Abrasive soaps also work
well, and often a r e preferred by
mechanics for removing oil and
grease from the palms.
25. The stripping action of abrasive cleansers is less likely to damage palmar skin where the stratum corneum is thick, but may
damage substantially the thinner
s t r a t u m corneum of the dorsal
hands and forearms, particularly if
used frequently.
26. Waterless hand cleansers are
generally less irritating to the skin
than abrasive cleaners.
27. Soaps and detergents used
for industrial cleaning of fabrics or
hard surfaces pose a greater potential for causing d e r m a t i t i s .
These products also serve one of
three general purposes. General
cleaning of floors and other hard
CLEAN COOLANT
sitize or depigment the skin, and
water-proof gloves should be worn
when using these agents.
31. Finally, a number of specialty industrial cleaning agents
have been designed for specific
cleaning operations. Detergents
used to clean ovens and charred
cookware are strongly alkaline and
contain about five per cent sodium
hydroxide with large amounts of
other alkaline substances. Caustic
burns may result if these products
c o n t a c t t h e skin and are not
washed off promptly, or are trapped against the skin inside protective gloves or clothing.
32. Products designed to "strip"
floors and other surfaces also are
strongly alkaline and carry the
same risk. Toilet bowl cleaners
may be strongly acidic and carry
the same risks of producing skin
b u r n s as the strongly alkaline
products; additional care must be
taken not to clean with bleach at
the same time, because chlorine
gas may be released when bleach
and acid are combined.
33. Scouring powders contain
CLEAN COOLANT
LINE
LINEV
FILTER TUBE TANK
WITH DRAG—OUT
HEADER
SUCTION BOX
MACHINE
TOOL
PRESSURE
GAUGE
F I L T E R PUMP
V A C U U M GAUGE
4-WAY A U T O M A T I C V A L V E
Figure 1 shows a two-compartment reservoir of a filter
system — the filter tank and the clean oil tank. Unfiltered liquid from the filter tank Is drawn by vacuum
through either leaf or tube filter elements. Solids are
deposited on the surface of the elements, and clean
coolant Is pumped through a four-way valve to the
clean storage tank. As contamination deposits form a
cake on the filter elements, the flow is restricted causing the liquid level In the filter tank to rise. (Photo:
Courtesy Indiana Commercial Filters Inc.)
PRESSURE
GAUGE
F I L T E R PUMP
V A C U U M GAUGE
4-WAY A U T O M A T I C V A L V E
Figure 2 shows action of the backwash cycle in a twocompartment reservoir. At a predetermined level, a
timer control or float actuates a solenoid air valve that
turns the four-way valve to reverse the liquid flow
through the filter. Clean coolant backwashes deposits
off the elements, and the chain driven flights remove
the residue in the filter tank. By this arrangement,
backwashing does not interrupt continuous flow from
the clean tank to the machine tool. (Photo: Courtesy Indiana Commercial Filters Inc.)
aA
i
7«
^
abrasives, but are much more alkaline than abrasive mechanics'
soaps. Because of their potential
for causing dermatitis, protective
gloves normally should be worn
whenever using any industrial
cleaner.
Protective equipment
and clothing
34. On many operations, liquidproof aprons are almost a necessity to p r e v e n t the employees'
clothing from becoming contaminated by coolant s p u r t i n g or
splashing from the tool. The apron
strings must be of a material easily broken, in case the apron
should become caught in moving
machine parts.
35. In many plants, operators
are provided with special preparations to rub into their hands and
arms before they s t a r t to work.
Certain creams are not water-soluble, being made specifically to
protect against aqueous solutions.
Some creams are soluble in water,
so that, while they protect the skin
from insoluble cutting oil, they offer less protection where soluble
cutting fluids are used.
36. Solvent-resistant creams are
also available. Be certain to provide creams for all potential exposures. Because no cream will repel
cutting oils for any considerable
length of time, repeated application is recommended.
37. Employees should put on
clean work clothes whenever necessary, at least twice a week, and
should keep them as clean as possible. Skin infections have resulted when workers have failed to
remove oil-soaked work clothing at
the end of the work day. Employees should be encouraged to
change into fresh clean clothing as
soon as each shift is completed.
Wiping material
MARCH 1086, NATIONAL SAPVTY AND HSALTN MIVI
ment of dermatitis. To control this
mixture does not support bacterial
f problem, it is suggested that the\
growth to any appreciable extent.
:j workers be supplied with disposa44. Animal oils do support mold,
ble towels.
and bacterial growth. Therefore,'
when they are used in cutting oils!
Reporting to first aid
the. oil manufacturer usually adds
an inhibitor, which slows down the
39. Workers who suffer cuts and
rate at which the oils become ranabrasions should be required to recid and usually r e s t r i c t s the
port to the plant nurse, first aid
growth of bacteria. In some cases
attendant, or plant physician at
the inhibitor itself is capable of
once for t r e a t m e n t to prevent
causing dermatitis.
these skin openings from becomi n g avenues for infection. Employees who develop skin disorders
Filtration
should likewise be required to report them promptly, and treat45. Oil that is used more than
ment should be given under the
once or has been reclaimed from
supervision of a physician.
cuttings and shavings by centrifuging or magnetic processing
should
be filtered to remove nonTraining and inspection
ferrous metallic and other particles to extend the life of both the
40. It is highly desirable that
cutting
tool and the oil or emulmanagement provide facilities for
sion.
The
type which best suits the
teaching employees personal hyneeds
of
the
individual plant can
giene. The employer should insist
be selected from a variety of filon observance of the rules regardtering systems.
ing personal cleanliness. Posters,
leaflets, and bulletin board mes46. In some shops, the used oil is
sages describing the sanitary meaconveyed into a large settling tank
sures necessary to prevent skin irwhere it is left for several days.
ritators and emphasizing the imDuring this time most of the chips
portance of personal cleanliness
and foreign matter will sink to the
will be of service in educating the
bottom. Due to the viscosity of the
employee.
oil, a great deal of the finer suspended matter will not settle out.
41. Such materials should also
This
method, therefore, is less efwarn the employee against the
ficient.
danger of contaminating the cutting oil by spitting or throwing
g a r b a g e or other contaminants
into the machines, drains, or oil
pans. Deliberate contamination of
coolants should be cause for disciplinary action.
Methods of control
42. Methods of control include
hygienic practices (which are the
most important), careful selection
of the fluids, filtration disinfection, and use of splash guards and
covers.
/
38. The use of rags or pieces of
waste for wiping the hands and
a r m s is a highly objectionable
practice. Such wiping cloths are
generally kept on or around the
machines or in the pockets of work
clothes. These rags or pieces of
waste are frequently loaded with
chips and dirt, which scratch and
lacerate the skin and in many
cases contribute to the develop.
Selection
43. Cutting oils that do not permit bacteria to breed and that are
non-irritating should be selected.
Mineral oil, the principal ingredient of cutting oils, is not a source
of germs and does not provide a
suitable medium for germ growth.
Even when small amounts of vegetable oils are added, the resulting
47. Settling tanks a r e more
often used for emulsions. These
solutions contain water, and metal
particles or other foreign matter,
which may be carried into the sediment tank will readily sink to the
bottom.
48. In large machine shops
where one mixture is used for a
number of machines, it is customary to install a circulating system
for the cutting oils. The oil flows
or is pumped from a supply tank
directly to the machines and
drains from thai machines through
pipes to a central collection tank.
49. Where a continuous circulating system is installed, it is highly
desirable to include as part of the
system a filtering and disinfecting
unit so t h a t oil t h a t drains from
the machines will pass through the
filter and sterilizer before being
pumped back to the supply tank.
50. Shops t h a t do not have a
continuous circulating system
commonly use the batch filtration
MAACM IMS. NATIONAL SAPCTV AND NHALTH
system. Once each week, or more
often, the oil is collected from the
base of each machine by a tank
truck, from which it is run into a
pipe outlet on the same floor and
piped to the filter and sterilizer.
51. The oil is f i l t e r e d , disinfected. and delivered to a clean oil
pipeline with an o u t l e t on each
machine room floor, f r o m which
the clean oil. u n d e r s u f f i c i e n t
pressure to cause flow, is run into
the clean oil c o m p a r t m e n t of the
tank t r u c k f o r delivery to each
machine base.
52. The oil receptacles and pipes
of machines should be thoroughly
cleaned each t i m e t h e oil is removed. Filtering and disinfecting
may be done when the plant is not
in operation. The results obtained
f r o m t h e batch s y s t e m will obviously d e p e n d upon t h e frequency with which the oil is removed f r o m t h e individual machines for purification. W h e r e a
central system feeds more than a
few machines with soluble cutting
oil, it is virtually impossible to disinfect all lines completely during
the cleaning process, and some residual bacteria are possibly introduced into the new coolant almost
as soon as it is added.
53. It is possible to provide for
continuous filtration on an individual machine by placing a small filter on it. Machine tool builders are
now equipping most of these machines with such filters.
Disinfection
54. Application of h e a t is one
method for disinfecting c u t t i n g
oils and e m u l s i o n s . To h e a t t h e
cutting mixture, it is the general
practice to place s t r e a m pipes or
coils in t h e r e s e r v o i r into which
the oil flows before or after being
filtered. A t e m p e r a t u r e of 180 F
(80 C) for 25 minutes to one hour
is used for cutting oils. Emulsions,
which break down at higher temperatures, are held at 140 F (60 C)
for 30 minutes. Because disinfection is m o r e likely" t o r e s u l t a t
higher t e m p e r a t u r e s , emulsions
that can stand the heat should be
held at 180 F. In any case, recommendations of the m a n u f a c t u r e r
should be sought and followed in
d e t e r m i n i n g t h e best method of
disinfection.
55. The second method of disin-
" V
fection is the use of germicides.
The m a n u f a c t u r e r ' s instructions
should be c a r e f u l l y followed to
eliminate any possibility of using
too much germicide, which may
cause the skin to react both physically and chemically.
nue South. New York 10016.
Encyclopaedia Britannica. 15th Edition, 1977. Encyclopaedia Britannica.
Inc.. 310 S. Michigan Avenue. Chicago 60604. Volume 16. pp. 914-919.
Adams, R.M.. Occupational
Skin
Disease. 1983. Grune and Stratton.
do Academic Press. Orlando, FL
Splash guards and covers
32887.
56. Splash g u a r d s a t t a c h e d to
cutting machines will not only prevent the w o r k e r s ' clothing f r o m
becoming soiled but will also save
oil. In addition, all tanks in which
cutting fluids are stored should be
kept tightly covered to prevent
dust. dirt, and germs from entering them.
Hazards
Lipid pneumonia*
57. The question of the production of a pneumonia or pneumonitis from oil mist frequently arises.
Although the opinion t h a t these
c o n d i t i o n s could p e r h a p s result
from exposure to oil mist has been
expressed, such a cause-and-effect
relationship has not been proven
by reliable clinical or laboratory
tests.
Skog, E. "Irritant Effect of Industrial Hand Cleansers." (A comparative investigation on guinea pig and
human skin.) Arch ices of Environmental Health. 4000 Albemarle Street.
NW. Washington, DC 20016. Vol. 7.
1963. pp. 682-685.
ACKNOWLEDGMENT
This data sheet has been prepared
by the Automotive, Tooling, Metalworking, and Associated Industries
Section of the Industrial Division, National Safety Council. 444 N. Michigan Ave., Chicago 60611.
An Alphabetical Index of all Industrial Safety Data Sheets (Product
N o . 1 2 3 . 0 9 - 0 0 0 0 ) is available from
ihe Council o n r^cuest.
Fire
58. The use of cutting oils, emulsions, and d r a w i n g c o m p o u n d s
may introduce certain fire hazards
unless good housekeeping practices are followed. For control of
fire hazards the recommendations
of the National Fire Prevention
Association bulletins for such installations should be followed.
-
^
^
-«ssssss^
REFERENCES
Occupational Skin Disease in California 1982 California Department of
Industrial Relations, Division of Labor and Statistics, 525 Golden Gate
Avenue. San Francisco 94102.
Soaps and Detergents. The Soap and
Detergent Association, 475 Park Ave-
t&gS&tS:
0
«SV
• Proud fit, P.J., H.S. Van Ordstrand.
and C.W. Miller, "Chronic Lipid
Pneumonia Following Occupational
Exposure.** Archives of Industrial
Hygiene and Occupational Medicine,
American Medical Association, 535
North Dearborn Street, Chicago
60611. Vol. 1. January 1950, page 105.
WRITE 8 ON READER CARD
V \
Huiles de coupe
et dermatoses cutanées
:>t/ .iûti't
*> JU. ••
,1 jfJ-.- j n:
Louis-Philippe Durocher0* et Nicole Paquette(2)
Résumé
Les huiles de coupe sont utilisées dans le secteur de la métallurgie. Elles peuvent causer des éruptions folliculaires, des dermites
de contact, des lésions proliférantes. Le potentiel cancérigène des
huiles de coupe est mal connu, ce qui doit nous inciter à une
surveillance vigilente des travailleurs qui les manipulent.
L
les huiles de coupe sont utilisées principalement dans le
Isecteurde la métallurgie. Les
huiles sont de deux sortes : huiles minérales extraites des pétroles et huiles
d'anthracène tirées du goudron de
houille. Les huiles d'anthracène ont été
associées à Pépithélioma du scrotum et
ne sont plus utilisées depuis de nombreuses années. Quant aux huiles minérales, leur association à un cancer cutané chez l'humain n'a pas été démontrée.
Classification des huiles
de coupe
Les huiles de coupe ont deux
fonctions principales dans l'industrie
métallurgique :
Refroidir la pièce à usiner et l'outil usinant.
Lubrifier les éléments à usiner et les outils
afin de diminuer la friction.
On leur reconnaît les fonctions secondaires suivantes :
1)
M . D . . professeur-adjoint de clinique. Université de Montréal ; chef du service de dermatologie, médecin-conseil en
santé au travail, hôpital MaisonneuveRosemont.
2)
M . D . . résidente en dermatologie.
Université de Montréal.
Tirés à part :
Louis-Philippe Durocher, M . D . , 5965, rue
Sherbrooke Est, Montréal (Québec) H IN
IB7.
Article reçu le :
20.12.85
Avis du comité de lecture le :
11.2.86
Acceptation définitive le :
20.3.86
730
Chasser les copeaux et la boue de meulage.
Protéger de l'oxydation la pièce usinée.
Pour remplir ces fonctions, les
huiles de coupe doivent posséder des
caractéristiques chimiques précises. De
nombreux additifs sont ajoutés aux
huiles (désinfectant, anti-rouille, détergent, etc.) afin d'éviter l'usure prématurée. On ajoute aussi des produits dits
à haute pression destinés à empêcher la
liaison de la pièce usinée avec la pièce
correspondante.
On divise les huiles de coupe
en trois catégories : huiles de coupe
simples ou insolubles, huiles de coupe
émulsifiables ou solubles et fluides
synthétiques ou de refroidissement.
Actuellement, les huiles les plus utilisées sont les huiles émulsifiables, toutefois les fluides synthétiques gagnent
en popularité. Chaque catégorie d'huile
se distingue par sa composition chimique (tableau I). Les fluides synthétiques se composent de trois éléments :
de l'eau, du nitrite de sodium et une
amine tertiaire (triéthanolamine).
L'eau agit comme solvant, lubrifiant et
refroidisseur. Quant à l'aminé et au nitrite, ils ont un effet anti-corrosif. Parfois un agent bactériostatique est ajouté
pour prévenir la dégradation des fluides
par des micro-organismes.
Historique
En 1731, Bassius décrit l'épithélioma du scrotum. Percivall Pott,
en 1775, relie ce cancer à une exposition professionnelle à la suie chez les
ramoneurs. L'épithélioma du scrotum
est reconnu dès lors comme une dermatose professionnelle. Au cours du siècle
suivant. Volkman, en Allemagne, souligne la présence d'épithélioma du
scrotum parmi les ouvriers d'une raffinerie de houille. En 1850. on introduit
dans les filatures de coton un procédé
entraînant l'utilisation d'huile minérale. Vingt ans plus tard, soit en 1876,
Bell observe des carcinomes du scrotum chez les tisseurs. En 1920, on incrimine les noyaux d'anthracène présents dans les huiles de houille comme
élément cancérogène. Puis on précise
que c'est la liaison des noyaux
d'anthracène avec des noyaux aromatiques de type benzénique ayant lieu à
haute température (> 700°C) qui géL ' U N I O N MÉDICALE DU CANADA
I
V
cou. Waterhouse 6 en 1971 fait le relevé
de 135 cas de cancer du scrotum dans la
région de Birmingham.
Tableau I
Composition des huiles de coupe 1
Tableau clinique
Huiles de coupe insolubles :
Base d'huile minérale
60 à 100 %
Huiles grasses (baleine, saindoux)
0 à 40 %
Bactéricides
Additifs «extrême pression»
• soufre
1à 3 %
. • chlore
1à 3 %
Parfums
0.05 %
Huiles de coupe solubles :
Base d'huile minérale
Émulsifiant
- Primaire (sulfonate de sodium)
' - Secondaire (sulfonate de pétrole)
'Bactéricides
60 à 80 %
4 %
0.1 à 2 %
Anticorrosif (hydroxy lamine)
Additifs d'extrême pression
« 30 %
Antimousses (silicone)
Colorants
Agents de conditionnement de l'eau
(polyphosphate et phosphate trisodique)
Anti-usure (phosphate de tricesyle)
Eau
Huiles de coupe synthétiques :
Nitrite de sodium
Amine tertiaire (triéthanolamine)
Eau
18 %
45 %
nère des produits cancérigènes1. On
propose alors l'utilisation de lubrifiants
pétroliers en lieu et place des huiles de
houille.
A la température de distillation de la houille (1000°C) l'accollement des noyaux est facile. Le danger
est écarté par l'utilisation d'huiles de
pétrole, car le pétrole brut contient peu
de noyaux anthracéniques et la distillation étant complétée avant 700C, la liaison ne peut avoir lieu. Après ces découvertes et rétablissement de normes
quant à l'utilisation des huiles de coupe
à partir de distillats de pétrole, on note
une diminution de l'incidence du cancer du scrotum.
Au cours des vingt dernières
années, dans deux régions surtout (Birmingham en Angleterre et la HauteSavoie en France), on a noté de nouveaux cas de cancers du scrotum et cela
malgré l'utilisation d'huile de pétrole.
Dans la région des Cluses, de 1960 à
1974, Thong: a démontré 133 cas d'épithélioma spino-cellulaires parmi
5054 individus exposés aux huiles. Les
lésions malignes siégeaient au niveau
du scrotum dans 63 % des cas, au niveau des avant-bras et des mains dans
30 % des cas et rarement à la face et au
Tome 115 —OCTOBRE 1986
Les huiles de coupe simples
ou insolubles peuvent causer une éruption cutanée folliculaire sise à la face
dorsale des mains, aux avant-bras, aux
hanches, à la figure et au cou. On observe une obstruction mécanique de
l'orifice du follicule pileux entraînant
la formation de comédons et d'une inflammation péri-folliculaire.
Les huiles de coupe solubles
et les fluides synthétiques peuvent cauj3jrûnedermiïedec^
irritative. La dermite irritative est secondaire à l'effet destructeur des produits alcalins sur la couche cornée et le
film lipidique présent à la surface de
l'épiderme. La réaction se caractérise
par une sécheresse de la peau avec fissures ; ultérieurement, on observera
une eczématisation franche si le processus s'amplifie. Les doigts, les mains et
les avant-bras sont touchés. La réponse
cutanée varie d'un individu à l'autre en
fonction de facteurs personnels (âge,
type de peau, exposition antérieure),
mais elle varie aussi dans le temps pour
un même individu en fonction de facteurs circonstantiels (durée d'exposition, degré d'exposition). La dermite
irritative par contact constitue le problème cutané le plus fréquemment rencontré avec les huiles de coupe. Les
dermites allergiques par contact sont
plus rares. Les allergènes les plus fréquemment incriminés sont les additifs :
bactéricides (chlorocrésol, formaldéhyde, dichlorophène), antioxydants,
colorants et parfums4.
A la suite d'une exposition
chronique aux huiles de coupe, on peut
observer des lésions proliférantes de
type papillomes kératosiques ainsi que
des kératoacanthomes. Le kératoacanthome est une tumeur épithéliale bénigne qui ressemble cliniquement et
histologiquement à un épithélioma spino-cellulaire. Cliniquement il se présente sous forme d'une excroissance de
1 à 2 cm avec un centre ombiliqué occupé par un bouchon de kératine. La
lésion régresse spontanément en 2 à 8
mois-.
Cancers et huiles de
coupe
Que dire de la relation entre
les épithélioma spino-cellulaires et
l'exposition aux huiles de coupe ?
Chez les animaux, les huiles de coupe
usées se sont avérées cancérigènes.
Chez l'humain, sauf pour l'huile de
houille, aucune étude n'a démontré de
pouvoir cancérogène des huiles de
coupe.
Les huiles de coupe sont absorbées par voie cutanée après contact
direct ou par inhalation de fines gouttelettes pulvérisées autour de la machineoutil. Les études de morbiditémortalité reliées aux huiles ont étudié
l'incidence et la mortalité des cancers
cutanés, digestifs et respiratoires.
Waterhouse6 a étudié la période de 1950
à 1967 à Birmingham et a noté une
incidence supérieure de cancers, cela
de façon significative, chez les ouvriers
exposés aux huiles de coupe lorsque
comparés à la population en général.
Les- sites les plus souvent atteints
étaient la peau, les tractus respiratoire
et digestif. Toutefois, une étude américaine de Decoufle7 couvrant la période
de 1938 et 1967 n'a pas montré d'incidence accrue de néopiasie. Une incidence accrue de cancers cutanés n'a été
observée que dans deux régions : Birmingham, en Angleterre et la HauteSavoie, en France. Est-ce que cela
s'explique par la haute concentration
d'industries utilisant des huiles de
coupe dans ces deux régions ? Est-ce
dû à de meilleurs registres de morbidité, mortalité ? Est-ce secondaire à
l'utilisation d'huiles de coupe différentes de celles utilisées ailleurs (Hollande, Australie, États-Unis) où les
études n'ont pas montré d'incidence accrue de néoplasies3 ? Toutes ces questions demeurent sans réponse.
Les études animales ont
montré que les huiles de coupe pouvaient s'avérer cancérogènes. Désoillé3
en 1973 a montré l'action cancérigène
des huiles usées chez la souris. L'action
cutanée des huiles usées chez la souris
provoquait l'apparition de tous les intermédiaires entre le papillome banal,
la dysplasie et le carcinome. Les benzopyrènes et les nitrosamines sont présentes dans certaines huiles de coupe.
Ces substances sont reconnues cancérogènes chez l'animal.
Benzopyrène
Le benzopyrène est un hydrocarbure aromatique polycyclique à cinq
cycles. En 1968, le conseil médical de
la recherche de Grande-Bretagne incrimine les hydrocarbures aromatiques
polycycliques à quatre ou cinq cycles
comme composés cancérogènes. Tho-
731
ny en 1976 a signalé la présence de
concentrations variables de benzopyrène (0,5 à 150 mg/1 ) dans des huiles de
coupe neuves. En France, le centre de
recherche de l'I.N.R.S. 1 a décelé des
quantités importantes de benzopyrène
dans l'huile usée (20 mg/kg) alors que
l'huile neuve n'en contenait que peu
(0,6 à 0,8 mg/kg). Cela démontre l'enrichissement en substance cancérogène
d'une huile usée.
Mehrotra8 en 1979 a appliqué,
. pendant trois cents jours, des huiles uti/J
iisées dans le trempage de la jute sur la
peau de souris. Il n'a noté aucun cancer
cutané. Toutefois, aucun hydrocarbure
aromatique polycyclique n'a été re^trouvé dans ces huiles. L'application,
selon le même protocole d'huile de
trempage additionnée de benzopyrène,
a entraîné le développement de tumeurs
cutanées.
- .
» •
Nitrosamines
Les fluides synthétiques se
composent de 45 % de triéthanolamine
et de 18 % de nitrite de sodium dans de
l'eau. Le triéthanolamine commercial
peut contenir jusqu'à 15 % de diéthanolamine comme impureté9. On sait
que les amines secondaires et tertiaires,
en réagissant avec les nitrites, entraînent la formation de nicrosodiéthanolamine. Certains fluides synthétiques ne
contiennent pas de nitrite ; toutefois,
les amines peuvent réagir avec l'oxyde
d'azote de l'air ambiant et former des
nitrosodiéthanolamines10. L'intérêt du
nitrosodiéthanolamine réside dans ses
propriétés cancérogènes démontrées
chez les animaux. Le nitrosodiéthanolamine est cancérogène chez le rat après
une dose orale (600 à 1 000 mg/kg).
Son ingestion a provoqué des cancers
hépatiques et quelques adénomes rénaux. L'administration sous-cutanée
(500 à 2 260 mg/kg) chez des hamsters
a fait apparaître des adénocarcinomes
de la cavité nasale et des tumeurs de la
trachée. On n'a pas observé d'épithéliomacutané chez les animaux étudiés4.
On ne connaît pas la toxicité
du nitrosodiéthanolamine chez l'humain. On sait que ce composé est absorbé par voie cutanée et excrété dans
l'urine chez l'humain.
Facteurs contributifs
Dans la genèse des lésions cutanées, plusieurs facteurs sont à considérer : des facteurs mécaniques, des
facteurs chimiques et des cofacteurs.
732
Facteurs mécaniques
Ces facteurs facilitent l'absorption des substances. Ainsi le frottement sur la peau du bleu de travail et
des sous-vêtements imprégnés d'huile
augmente la pénétration de celle-ci. De
plus, la température de l'huile au
contact du métal en usinage est voisine
de 400°C donnant ainsi naissance à un
brouillard d'huile ; le machiniste peut
être exposé à une pluie de fines gouttelettes d'huile.
Facteurs chimiques
Les risques inhérants à une
huile minérale varient selon son origine
et sa composition. De plus, nous avons
déjà mentionné que les huiles se modifient en cours d'utilisation. La température élevée à laquelle sont soumises les
huiles est susceptible d'en altérer la
composition.
Cofacteurs
Certaines substances peuvent
agir de façon synergique avec un carcinogène et potentialiser son action. Ainsi l'action cancérogène du benzopyrène
est augmentée par la présence de
chaînes aliphatiques et d'hydrocarbures aromatiques (N-dodécane) qui se
retrouvent dans certains solvants.
Prévention
Pour prévenir les atteintes à la
santé des travailleurs utilisant des
huiles de coupe, on doit modifier les
facteurs chimiques et mécaniques et
minimiser les cofacteurs.
Prévention collective
Ce type de prévention vise les
travailleurs en tant que groupe et
concerne surtout l'organisation du travail. Plusieurs mesures sont à considérer :
1.
Le choix des huiles de coupe :
• Utiliser des huiles dérivées du pétrole ou
des fluides synthétiques.
• Renouveler fréquemment les huiles et
prévoir des vidanges régulières des machines.
• Filtrer les huiles de récupération afin d'éliminer les particules métalliques et les déchets.
2..
L'élimination des brouillards
d'huile :
• Utiliser des appareils de régularisation du
débit d'huile.
• Utiliser des écrans protecteurs.
• Encoffrer les machines.
• Aérer les ateliers.
• Réduire la concentration des machines
dans un même atelier.
• Automatiser les opérations d'usinage.
Prévention individuelle
Ce type de prévention vise le
travailleur comme individu. Le travailleur devrait porter un tablier et des
bleus de travail à manches longues. Les
vêtements devraient être lavés au moins
deux fois par semaine et les sousvêtements changés tous les jours. Il est
reconnu que la pratique qui consiste à
garder des chiffons souillés dans les
poches doit être combattue. L'hygiène
personnelle est un facteur important et
le travailleur se doit d'être vigilant. Il
doit prendre sa douche après son quart
de travail pour limiter la durée de
contact avec l'huile. Le lavage des
mains doit être fréquent. Les solvants
pétroliers ou les pâtes abrasives sont à
déconseiller. L'utilisation d'une crème
protectrice diminue le contact des
huiles avec la peau et facilite le lavage.
Le recours à un intermédiaire
de manipulation peut limiter le contact
avec les huiles de coupe. Le port de
gants est recommandé pour les travaux
de nettoyage en s'assurant que les gants
n'entraînent pas un risque d'accident.
Parce que les huiles de coupe
peuvent altérer la surface lipidique naturelle de la peau, on recommande
l'emploi de lotion hydratante après la
journée de travail.
Intervention médicale
précoce
11 n'existe aucun indicateur
spécifique pour déceler les individus à
risque de développer une dermatose ou
un épithélioma lorsqu'exposés aux
huiles de coupe. Toutefois il est justifié
d'aviser les individus ayant une histoire
antérieure d'eczéma des risques accrus
de dermite.
Le travailleur sensibilisé
pourra favoriser l'intervention médicale précoce. Le médecin doit examiner avec une attention particulière les
téguments des travailleurs exposés et
rechercher spécifiquement les lésions
eczémateuses, folliculaires et cancéreuses.
L'UNION MÉDICALE DU CANADA
V \
«k '
Summary
Cutting oils are used in metal"" lurgy. They can cause follicular eruption,
. contact dermatitis and proliferative lesions. Cancer hazards from cutting oils
.
still need to be defined more accurately.
'Health of exposed workers must be
supervised with caution.
NECROLOGIE
i Raoul Groulx, m.d.
1917-1986
I
Bibliographic
r-
._. ^ " Î ' - . y .
%
-^k.• caucérogène des huiles minérales utilisées dans 'indus^ p ^ i i î ï trie. Thèse. Université de Paris. V. 1974.
2. Thong C., Thong J., LaTontaJne M. et Llmasset
J.C. : Concentrations en hydrocarbures polycycliques
aromatiques caocérogtnes de quelques huiles minérales.
Archives des maladies professionnelles de médecine du
travail et de sécurité sociale. 1975 ; 36 (1-2) : 37-52.
3. Désofllé H., Philibert M., Rlpault G., Cavigneaux A. et RossIgnoU H. : Action cancérogène des
huiles minérales utilisées en métallurgie. Archives des
maladies professionnelles de médecine du travail et de
sécurité sociale. 1973 ; 34 (12) : 669-680.
4. Lucas J.B. et coll. : Health hazard evaluationtoxicity-determination-report 74-103-182. Institute for
occupational safety and health. 1975 : 6 p.
5. MoscheUa S.L. et Hurley H J . : Dermatology.
W.B. Saunders. Philadelphie. 1985 ; 1542-1543.
6. Water house J.A.H. : Cutting oils and cancer.
Ann. Occup. Hyg., 1971 ; 14 : 161-170.
7. Decoufle P. : Further analysis of cancer mortality
patterns among workers exposed to cutting oil mists. J.
Nat). Cancer Inst.. 1978 : 61 (4) : 1025-1030.
8. Haguenoer J.M. : Les cancers professionnels, éd.
techniques et documentation. Lavoisier. 1982. Cancers
de la peau. p. 65 & 141.
9. Cooper S. et Fadlailah S. : Détection et identification des composés N-Nitroso dans les industries de métaux. I.N.R.S.-Santé. Montréal.
10. Smith A.M. et Woodward K.N. : NNitrosodiéthanolamine part III. Toxicity. Review 8.
1983.
T o m e 115 — OCTOBRE 1986
Nous nous joignons à Moservice de gynécologie. Pendant 2
nique Groulx et à ses enfants pour
ans, il collabore à la rédaction des
regretter la perte du docteur Raoul
statuts et règlements puis à jeter
Groulx, survenue à Montréal le 10
les bases de ce qui deviendra plus
janvier 1986.
tard le département d'obstétriqueLe docteur Groulx naît à St- gynécologie. Après l'ouverture de
Laurent le 9 novembre 1917. Il fait
l'hôpital, on reconnaît tôt, en lui, un
ses études classiques au collège St- leader et il occupe un poste à l'exéLaurent. Élu président de sa classe
cutif pendant 8 ans dont 2 ans
en philosophie, il obtient son B.A.
comme président. Il dirige le déparen 1939.
tement qu'il a fondé jusqu'en 1972.
Il étudie la médecine à
En 1960 à Montréal, l'obl'Université de Montréal et obtient
stétrique et la gynécologie sont enson doctorat en 1944. Il est vicecore deux spécialités séparées. Il
président de sa classe. De 1944 à
signe un éditorial dans L'Union mé1946, il fait de la résidence en chidicale du Canada, en novembre
rurgie générale à l'Hôpital général
1962 : "Mariage de raison". Grâce à
de Verdun puis de 1946 à 1948, en
son charisme, la fusion des deux
gynécologie sous la direction du
spécialités sera achevée en 1964.
docteur Gérard Gauthier. C'est au
En 1970, il fonde l'Associacours de cette période qu'il est
tion des obstétriciens-gynécologues
chargé de cours puis nommé produ Québec qu'il présidera jusqu'en
fesseur au département d'anatomie
1972. En 1979, une grave maladie
de l'Université de Montréal. L'ensei- l'oblige à cesser prématurément
gnement de l'anatomie en gynécoses activités.
logie est une spécialité du profesAvec la disparition du docseur Groulx. Une génération de réteur Groulx, la communauté médisidents a profité de son art, particu- cale perd un humaniste et un bâtislièrement en chirurgie vaginale.
seur. Certains phrases de lui témoiEn 1948, il est nommé chignent de marques d'humour, de sa
rurgien à l'Hôpital de Verdun. De
détermination et de sa philoso1949 à 1950, il fait un stage de gyphie : "Chaque journée dans la vie
nécologie à Boston dans le service
est intéressante si on a un défi à
du docteur Meigs. À son retour, il
relever." "Les hommes passent, les
exerce sa spécialité à l'Hôpital géinstitutions demeurent." "Les chinéral de Verdun et à l'hôpital Notre- rurgiens savent enlever un utérus,
Dame de l'Espérance de St-Laurent. les gynécologues ont appris à le
Il obtient son certificat de spéciaconserver." Il aura marqué le déliste en gynécologie du Collège des
partement d'obstétriquemédecins en 1952 et en 1953 du
gynécologie de MaisonneuveCollège royal du Canada. En 1954, il Rosemont pour plus d'une générareçoit le titre de Fellow du Collège
tion.
international des chirurgiens.
En 1952, les Soeurs Grises
Gilles Bernier, m . d .
construisent l'hôpital MaisonneuveF.R.C.S. (c)
Rosemont et à la suggestion du
Obstétricien-gynécologue,
docteur Marcel Ferron invitent le
Corporation professionnelle
docteur Raoul Groulx à fonder le
des médecins du Québec
733
O
- 0\"L\0
O'vJ"
'
SA
-
-
A -J
^
'
.
'
i'L'
".• ' '
.
...
•
A-
-)•
'
- '
à
.S
INTRODUCTION
Rased
on data from the National Occupational Hazard Survey, the National
million people in the United States are expire
ïSSSLy^^^SSSS:n i q u e s used have been documented
(4).
—
of machine tools.
1
2
——
i n t e n t i o n a l l y , by t h e a p p l i c a t i o n of a m e t a l w o r k i n g f l u i d a s an a t o m i z e d
mist.
HAZARD ANALYSIS
As n o t e d p r e v i o u s l y , t h e 5 mg/m3 e n v i r o n m e n t a l l i m i t recommended f o r p e t r o l e u m
b a s e d o i l s by t h e ACGIH i s i n t e n d e d a s an i n d e x of good i n d u s t r i a l Practice
r a t h e r t h a n a s a m a n d a t e f o r p r e v e n t i o n of i n j u r y . H a m i l t o n and Hardy (6)
i n d i c a t e t h a t e x p o s u r e t o m i s t s of i n s o l u b l e o i l s u s e d i n machining ° P * ™ t i o n s
a r e n o t harmful t o t h e r e s p i r a t o r y t r a c t , b u t add t h a t metalworking f l u i d s
may be t h e most common c a u s e of i n d u s t r i a l d e r m a t i t i s .
They include t h e
following a s c a u s a t i v e f a c t o r s :
Synthetic f l u i d s are potent defatting agents.
S o l u b l e o i l e m u l s i o n s p r o v i d e a b r e e d i n g ground f o r b a c t e r i a .
B a c t e r i c i d e s a r e added p r i m a r i l y t o p r e v e n t d e c o m p o s i t i o n and \\
odor f o r m a t i o n and n o t f o r t h e p r e v e n t i o n of s k i n i n f e c t i o n s .
F l u i d a d d i t i v e s c a n be a c a u s e of e i t h e r p r i m a r y i r r i t a t i v e
hypersensitive dermatitis.
H a m i l t o n and Hardy (6)
leum o i l s , e s p e c i a l l y
States).
Skin cancer
those t h a t occur in a
or
c i t e t h e c a r c i n o g e n i c c o n s t i t u t e n t s of c e r t a i n p e t r o s h a l e o i l s ( n o t m a n u f a c t u r e d and u s e d i n t h e U n i t e d
i s n o t known t o o c c u r i n numbers s i g n i f i c a n t l y above
control population.
R e - r e f i n e d s t r a i g h t o i l was u s e d i n one p l a n t s u r v e y e d . An a n a l y s i s of t h i s
o i l i n t h e " a s r e c e i v e d " c o n d i t i o n f o r p o l y n u c l e a r a r o m a t i c h y d r o c a r b o n s was
a t t e m p t e d , and p e r y l e n e and c h r y s e n e t e n t a t i v e l y i d e n t i f i e d b u t n o t q u a n t i f i e d
(7)
F u r t h e r r e s e a r c h i s needed t o compare c a r c i n o g e n i c c o n s t i t u t e n t s i n
p e t r o l e u m o i l s , new and r e - r e f i n e d , b o t h a s r e c e i v e d from t h e m a n u f a c t u r e r and
a f t e r normal machine u s e . As t h e p r i c e of o i l c o n t i n u e s t o s o a r and e n v i r o n m e n t a l r e s t r i c t i o n s i n c r e a s e , t h e u s e of r e - r e f i n e d o i l s and s y n t h e t i c f l u i d s
w i l l grow.
I
|
The u s e of s y n t h e t i c c u t t i n g f l u i d s h a s r e c e n t l y become q u e s t i o n a b l e , due t o ^ —
t h e d i s c o v e r y of d i e t h a n o l n i t r o s a m i n e , a s u s p e c t e d c a r c i n o g e n , a s a p r o d u c t H
from t h e r e a c t i o n of a m i n e s w i t h n i t r i t e s , b o t h of which a r e common i n com- ,
m e r e i a l l y a v a i l a b l e f l u i d s ( 8 ) . No e n v i r o n m e n t a l l i m i t e x i s t s f o r a i r b o r n e ,
c o n c e n t r a t i o n s of s y n t h e t i c f l u i d s , a l t h o u g h s t a n d a r d s may e x i s t f o r s p e c i f i c
a d d i t i v e s or components.
ENGINEERING CONTROLS
I
|
•
789
The b a s i c p r i n c i p l e s of c o n t r o l , s u b s t i t u t i o n , i s o l a t i o n , and v e n t i l a t i o n a r e
a l l a p p l i c a b l e t o t h e c o n t r o l of m e t a l w o r k i n g f l u i d m i s t . More s p e c i f i c a l l y ,
t h e s e p r i n c i p l e s i n v o l v e t e c h n i q u e s and e v a l u a t i o n s c o n c e r n i n g f l u i d s e l e c t i o n ,
f l u i d a d d i t i v e s , m a c h i n e t y p e , s p l a s h g u a r d i n g , and v e n t i l a t i o n .
S p r i n g b o r n (5) o f f e r s u s e f u l g u i d e l i n e s f o r t h e s e l e c t i o n of m e t a l w o r k i n g
. f l u i d s f o r machining o p e r a t i o n s .
F a c t o r s e n t e r i n g i n t o s e l e c t i o n of a f l u i d
\
]
V N
I
i n c l u d e m a c h i n i n g c o n d i t i o n s , p e r f o r m a n c e r e q u i r e m e n t s , t o o l d e s i g n , and
f l u i d c o s t a s w e l l a s working c o n d i t i o n s . The s y n t h e t i c and s o l u b l e o i l
m e t a l w o r k l n g f l u i d s a r e l e s s p r o n e t o fuming and m i s t i n g t h a n t h e s t r a i g h t
m i n e r a l o l l f l ^ b u t - c a r r y a g r e a t e r r i s k of d e r m a t i t i s . / ' T h e p o t e n t i a l s k i n
c a n c e r - h a z a r d from t h e u s e of m i n e r a l o i l b a s e d c u t t i n g f l u i d s can be r e d u c e d
by t h e u s e n o f ; r o i l s from which t h e c a r c i n o g e n s have been removed by s o l v e n t
extraction.
S t r a i g h t o i l s i n c o r p o r a t i n g a n t i - m i s t i n g polymer a d d i t i v e s have been i n t r o d u c e d
i n t o t h e m a r k e t p l a c e ; one m a n u f a c t u r e r c l a i m s r e d u c t i o n of m e c h a n i c a l l y p r o duced m i s t i n e x c e s s of n i n e t y p e r c e n t when compared t o c o n v e n t i o n a l o i l s
( 9 , 1 0 ) . Use of a n t i - m i s t i n g o i l s I s d i s c u s s e d i n t h e c a s e h i s t o r i e s .
S u b s t i t u t e s y n t h e t i c f l u i d s a r e a v a i l a b l e which e l i m i n a t e t h e p o t e n t i a l of
n i t r o s a m i n e f o r m a t i o n by removing n i t r i t e s from t h e f o r m u l a t i o n ; however,
t h e u s e r c o n t e m p l a t i n g any change i n c u t t i n g f l u i d s s h o u l d g i v e f u l l c o n s i d e r a t i o n t o t h e p o t e n t i a l h a z a r d s of t h e s u b s t i t u t e .
In o r d e r t o p r o t e c t t h e machine o p e r a t o r f r o m c u t t i n g f l u i d s p l a s h and moving
machine p a r t s , Cookson (11) o f f e r s t h e f o l l o w i n g g u i d e l i n e s f o r t h e c o n s t r u c t i o n
of machine g u a r d s :
Guards must be a s r o b u s t a s p o s s i b l e and r i g i d l y s u p p o r t e d where
possible.
Guards which a r e n o t p e r m a n e n t l y f i x e d w i l l be e a s i l y removed a n d ,
what i s v e r y i m p o r t a n t , j u s t a s e a s i l y r e p l a c e d . T h i s o f t e n l e a d s
t o t h e u s e of s l i d i n g g u a r d s .
I f t h e guard o b s c u r e s t h e view of t h e working a r e a , s h a t t e r - p r o o f
windows w i l l a v o i d t h e t e m p t a t i o n t o l e a v e t h e guard o f f .
Guards d e s i g n e d on a n o v e r l a p p i n g d r i p - p r o o f p r i n c i p l e have a d v a n t ages over s e a l e d , a b u t t i n g t y p e s .
The c u t t i n g of a p e r t u r e s t o a l l o w f o r t h e p a s s a g e of p i p e s o r
c o n d u i t s h o u l d be a v o i d e d .
O t h e r methods of r e d u c i n g o p e r a t o r f l u i d c o n t a c t by machine m o d i f i c a t i o n which
a r e a l s o c i t e d by Cookson i n c l u d e : a u t o m a t i o n ( p a r t i c u l a r l y i n l o a d i n g and u n l o a d i n g of t h e m a c h i n e ) , improved swarf h a n d l i n g , p r e - s e t t o o l i n g , and
numerical c o n t r o l .
S c h u l t e (4) s t a t e s t h a t t h e most e f f e c t i v e method of
c o n t r o l l i n g m i s t from m a c h i n i n g o p e r a t i o n s i s a c o m b i n a t i o n of e n c l o s u r e and
l o c a l exhaust v e n t i l a t i o n .
I n most c a s e s , t h e e x h a u s t a i r i s p a s s e d t h r o u g h
an e l e c t r o s t a t i c p r e c i p i t a t o r and r e t u r n e d t o t h e workroom. F i l t e r s (12) and
c e n t r i f u g a l m i s t c o l l e c t o r s (13) a r e a l s o u t i l i z e d .
While t h e u s e of t h e s e
u n i t c o l l e c t o r s ( i n d i v i d u a l a i r c l e a n e r s mounted d i r e c t l y on a g i v e n machine)
i s wide s p r e a d , t h e i r u s e s h o u l d be l i m i t e d t o r e l a t i v e l y s m a l l f a c i l i t i e s
s i n c e l a r g e numbers of a i r c l e a n e r s d i s t r i b u t e d t h r o u g h o u t t h e workroom can
p r e s e n t s i g n i f i c a n t m a i n t e n a n c e p r o b l e m s . Plenum t y p e e x h a u s t s y s t e m s w i t h
l a r g e , c e n t r a l l y located a i r c l e a n e r s a r e i d e a l l y s u i t e d f o r metalworklng
f l u i d m i s t c o l l e c t i o n s y s t e m s b e c a u s e of t h e e a s e w i t h which b r a n c h d u c t s can
4
i
i
s-s
1
Care must be t a k e n i n t h e d e s i g n of such
be a d d e d , removed, or " ^ ^ ^ f t s
t o d r a i n and t o p r o v i d e f o r
systems t o a l l o w condensed m i s t and d r o p i e
^ fQund ^
adequate f i r e P a c t i o n
^ ^ / " I . C ^ L d P r a c t i c e ( 1 4 ) , and i n
ANSI Z9-2-1971 ( 1 5 ) .
s t hoods should be d e s e e d
H
and the o p e r a t i o n observed wh n
'aire,i
o
p
e
r
a
t
i
o
n
.
H
thrown from t h e
guards s i n c e an i n d r a f t of a i r w i l l
enclosures
w i t h wlndowed
Many machine t o o l s a r e
t h e manuf c
^
r e a d i l y
opened
d e s i g n e d so t h a t t h e
J®""® „chlned.
S u i t a b l e e n c l o s u r e s can
or moved f o r p l a c i n g and removing of p a r t s machi
•
^
m a n u f a c t u r e r .
u s u a l l y be c o n s t r u c t e d i f such
^
»
' »
cfm ln o r d e r to
provide
Exhau
s
"
u
p
p
l
i
e
d
^
«hïrê t h . degr.« ot . „ c l o , u r , 1.
o.pro.l.,d.
i n a workroom, and t h e t o t a l
When a l a r g e number of s o u r c e s a r e d i s r i b u t e d i ^ a
( d l l u t l o n )
amount of m e t a l w o r k i n g f l u i d m i s t
" e l
v e n t i l a t i o n can p r o v i d e e f f e c t i v e
»n™e£
from t h e m i s t s o u r c e . As g e n e r a l v e n t i l â t
t a m i n a t e d a i r w i t h uncontaminated a i r , t h e " t e ^
e n o u g h away
d
i
l
u t i o n of c o n e r s t0 the
t
generation
contaminan
^
&ir ^
I n t h e c a s e
of
e r
"
Widespread u s e of a i r
^
^
^
accompanied by t h e r e c i r c u l a t i o n of e x h a u s t £ '
The
î E S . ' S
î S ^ ^ S r i S û t Ï Ï ' ^ -
L
r
u
ig
l
e
s
^
f a r
o
f
^
18
t
h
u
m
b
-
"
^
e v a l u a t e s
^
t h e
per-
a s m a l l p r o d u c t i o n machine
shop.
WORK PRACTICES
The r i s k of d e r m a t i t i s can ^ d l y V o S
E Ï ^ Ï Ï ^ ' - ^ i S
of
s o i l e d s k i n a t work b r e a k s f o l l o w e d by thorough « y
s
metalworking
an e m o l l i e n t cream i s a h y g i e n i c
a b r a s i v e c l e a n s e r s ae
f l u i d a p p l i c a t i o n s . The u s e of
The
8 h o u l d b e changed d a i l y .
^ c t f c n r L S r o Ï
6
!
t r L s e r p o c k e t s s h o u l d be d i s -
couraged.
. . , p r t a i n t y p e s of c h l o r i n a t e d s u l f u r i z e d c u t t i n g o i l s
D e r m a t i t i s can occur w i t h c e r t a i n t y p e s o
gradually breakwhen t h e y g e t i n t o a w a t e r m i s c i b l e f l u i d .
M m o 3 t anyone
a c i d .
down t h e c h l o r i n e i n ^ ^ ^ ^ r s c h
a s i t u a t i o n (5) . Care must be
taken t h a t ' o l l ^ a r e ^ e ^ i n e .
must b e t h o r o u g h l y c l e a n e d between
f l u i d changes
5
S o l u b l e o i l e m u l s i o n s a r e b r e e d i n g grounds f o r b a c t e r i a .
Cookson (11) r e commends e f f e c t i v e d r a i n i n g , c l e a n i n g ( b o t h f l u s h i n g w i t h a c h e m i c a l c l e a n s e r
and, p h y s i c a l c l e a n i n g ) , and s t e r i l i z i n g between c h a n g e s a s t h e most b e n e f i c i a l
•steps i n c o n t r o l l i n g i n f e c t i o n of c o o l a n t s y s t e m s .
PERSONAL PROTECTIVE EQUIPMENT
Oil r e s i s t a n t gloves provide p r o t e c t i o n from both d i r e c t metalworking f l u i d
c o n t a c t and n i c k s and s c r a t c h e s from p a r t s o r swarf h a n d l i n g . Gloves s h o u l d
be c u f f e d t o a v o i d e x p o s u r e t o t h e a r m s .
P r o t e c t i v e creams a r e of l i m i t e d v a l u e . G e r m i c i d e s p r e s e n t i n some p r o t e c t i v e
creams can be s k i n i r r i t a n t s ( 6 ) . Water s o l u b l e ( o i l i n s o l u b l e ) creams a r e r e q u i r e d t o p r o t e c t a g a i n s t o i l a t t a c k on t h e s k i n . T h e r e a r e no p r o t e c t i v e
creams which can h o l d up i n a d i v e r s i f i e d work e n v i r o n m e n t where t h e hands
w i l l fee exposed t o a m i x t u r e of o i l , s o l v e n t s , and w a t e r - b a s e d f l u i d s ( 5 ) .
As an i n t e r i m m e a s u r e , o i l r e s i s t a n t a p r o n s s h o u l d be used f o r p r o t e c t i o n
a g a i n s t s p l a s h e s u n t i l p r o p e r e n c l o s u r e s o r s p l a s h g u a r d s can be i n s t a l l e d .
6
METHODOLOGY
\
A l i t e r a t u r e s e a r c h was c o n d u c t e d t o d e t e r m i n e t h e n a t u r e and u s e of m e t a l working f l u i d s , t h e . e x t e n t of e x p o s u r e , and a p p l i c a b l e c o n t r o l t e c h n i q u e s .
Machine t o o l m a n u f a c t u r e r s , m e t a l w o r k i n g f l u i d p r o d u c e r s , c o n t r o l equipment
f a b r i c a t o r s , and o t h e r s were s o l i c i t e d f o r t h e i r recommendations a s t o p l a n t s
which o f f e r e d a v a r i e t y o f w e l l c o n t r o l l e d m a c h i n i n g o p e r a t i o n s . T h r e e p l a n t s
were s e l e c t e d f o r s t u d y t o r e p r e s e n t s t a t e - o f - t h e - a r t c o n t r o l t e c h n o l o g y f o r
,
t h e w i d e s t p o s s i b l e v a r i e t y tff o p e r a t i o n s w i t h i n t h e a l l o t t e d r e s o u r c e s .
I
Emphasis was g i v e n t o t h o s e m a c h i n i n g o p e r a t i o n s which u t i l i z e d s t r a i g h t
"
\
c u t t i n g o i l s , o p e r a t e d a t h i g h r o t a t i o n a l s p e e d s , - m a c h i n e d common m e t a l s
.
(mild s t e e l , c a s t i r o n , b r a s s ) , o r c o u l d be c l a s s i f i e d a s s e v e r e
for high
\
X
speed t o o l s . The s e v e r i t y of t h e m a c h i n i n g c o n d i t i o n s i s a r e l a t i v e i n d e x
!
of t h e l o a d on t h e t o o l and t h e amount of h e a t g e n e r a t e d . I t , t h u s , s e r v e s a s
an e s t i m a t e of t h e r e l a t i v e t e n d e n c y t o t h e r m a l l y g e n e r a t e m i s t .
C o n t r o l e f f e c t i v e n e s s was d e t e r m i n e d by c o m p l i a n c e w i t h a n e i g h t - h o u r t i m e
w e i g h t e d a v e r a g e of 5 mg/m 3 m i n e r a l o i l m i s t where s t r a i g h t and s o l u b l e m e t a l working o i l s were u s e d . Due t o t h e l a c k of an e n v i r o n m e n t a l s t a n d a r d f o r
s y n t h e t i c m e t a l w o r k i n g f l u i d m i s t s , t h e a i r b o r n e c o n c e n t r a t i o n s of n i t r i t e
was measured a s an I n d e x of t h e c o n t r o l a c h i e v e d .
Area a i r samples were t a k e n a t l o c a t i o n s a p p r o x i m a t i n g t h e b r e a t h i n g zone a t
t h e machine o p e r a t o r ' s work s t a t i o n .
Sampling was p e r f o r m e d a t s e v e r a l i d e n t i c a l machines p e r f o r m i n g s i m i l a r o p e r a t i o n s . A l l samples were c o l l e c t e d on 37 mm
membrane f i l t e r s u s i n g . a c a s s e t t e f i l t e r h o l d e r .
A n a l y s e s were p e r f o r m e d by e i t h e r f l u o r e s c e n c e of a c h l o r o f o r m e x t r a c t o r
i n f r a r e d a b s o r b a n c e of a c a r b o n t e t r a c h l o r i d e e x t r a c t . The a n a l y t i c a l p r o c e d u r e i s o u t l i n e d i n NIOSH P+CAM #159 ( 1 7 ) . ' A i r b o r n e l e v e l s of n i t r i t e s (where
s y n t h e t i c n i t r i t e - a m i n e f o r m u l a t i o n s were u s e d ) were d e t e r m i n e d u s i n g t h e
i d e n t i c a l s a m p l i n g t e c h n i q u e and t h e s p e c t r o p h o t o m e t r i c a n a l y t i c a l t e c h n i q u e
of NIOSH P+CAM 231 ( 1 7 ) .
7
TABLE 1 .
I.
II.
[II.
T u r n i n g Machines
1)
Lathes
2)
Automatic b a r and c h u c k i n g machines
D r i l l i n g Machines
1) D r i l l P r e s s e s
2)
Gundrills
Shapers/Planers
1)
2)
IV.
Broach p r e s s
P u l l b r o a c h machine
Continuous broaching
Surface broaching
B o r i n g Machines
1)
2)
3)
VII.
Knee and column m i l l i n g machine
B e d - t y p e m i l l i n g machine
Planer-type
Special purpose
B r o a c h i n g Machines
1)
2)
3)
4)
VI,
Horizontal and vertical shapers
Planers
Milling Machines
1)
2)
3)
4)
V.
Machine T o o l s
Horizontal boring mill
V e r t i c a l b o r i n g and t u r n i n g machines
J i g boring
Sawing and F i l i n g Machines
1)
2)
3)
Power hacksaw
C i r c u l a r saw
Bandsaw
32
VIII.
Grinding
1)
2)
3)
IX.
External cylindrical grinders
Internal cylindrical grinders
Surface grinder (horizontal/vertical)
F i n i s h i n g Machines
1)
2)
H o r i z o n t a l h o n i n g machine
V e r t i c a l s p i n d l e h o n i n g machine
33
V\o
TABLE 2 .
I.
Screw M a n u f a c t u r e
1)
2)
3)
II.
Gear
1)
2)
3)
III•
S p e c i a l t y Machines
U n i v e r s a l t h r e a d i n g machine
Universal thread miller
Thread r o l l i n g machines
C u t t i n g Machines
Gear s h a p e r s ( f o r m c u t t i n g )
Hobbing m a c h i n e s ( g e a r g e n e r a t i o n )
Gearshavers ( f i n i s h i n g )
Automated Machines
1)
2)
F i x e d programming
T r a n s f e r machines
34
te
TABLE 3 .
X.
Mineral Oil
1)
2)
3)
4)
II.
Base 60 - 100%» p a r a f f i n i e o r n a p h t h e n l c
Polar additives
a ) Animal and v e g e t a b l e o i l s , f a t s , and waxes t o wet and
penetrate the chip/tool i n t e r f a c e
b) S y n t h e t i c boundary l u b r i c a n t s : e s t e r s , f a t t y o i l s and a c i d s ,
p o l y o r complex a l c o h o l s
Extreme p r e s s u r e (EP) l u b r i c a n t s
a ) S u l f u r - f r e e , o r combined a s s u l f u r l z e d m i n e r a l o i l o r
sulfurlzed fat
b) C h l o r i n e - a s l o n g c h a i n c h l o r i n a t e d wax o r c h l o r i n a t e d
ester
c ) Combination - s u l f o - c h l o r i n a t e d m i n e r a l o i l o r s u l f o - c h l o r i n a t e d
fatty oil
d) P h o s p h o r o u s - a s o r g a n i c p h o s p h a t e o r m e t a l l i c p h o s p h a t e
Germicides
Emulsified O i l (Soluble Oil) - opaque, milky appearance
1)
2)
3)
4)
5)
6)
7)
III.
C u t t i n g F l u i d Composition
Base - m i n e r a l o i l , c o m p r i s i n g 50-90% of t h e c o n c e n t r a t e ; i n u s e
t h e c o n c e n t r a t e i s d i l u t e d w i t h w a t e r i n r a t i o s of 1 : 5 t o 1 : 5 0 .
E m u l s i f i e r s : p e t r o l e u m s u l f o n a t e s , amine s o a p s , r o s i n s o a p s ,
naphthenlc acids
P o l a r a d d i t i v e s - sperm o i l , l a r d o i l , and e s t e r s
Extreme p r e s s u r e (EP) l u b r i c a n t s
C o r r o s i o n i n h i b i t o r s : p o l a r o r g a n l c s , e x a m p l e : h y d r o x y l amines
Germicides
Dyes
Synthetics
1)
2)
1
3)
4)
5)
6)
(transparent)
Base - w a t e r , c o m p r i s i n g 50-80% of t h e c o n c e n t r a t e ; i n u s e t h e
c o n c e n t r a t e i s d i l u t e d w i t h w a t e r i n r a t i o s of 1 : 1 0 t o 1 : 2 0 0 .
True s y n t h e t i c s c o n t a i n no o i l .
Semi-synthetics are available
which c o n t a i n m i n e r a l o i l p r e s e n t i n amounts of 5-25% of t h e
concentrate.
Corrosion i n h i b i t o r s
a) Inorganics - b o r a t e s , n i t r i t e s , n i t r a t e s , phosphates
b) O r g a n l c s - a m i n e s , n i t r i t e s (amines and n i t r i t e s a r e t y p i c a l
and c h e a p )
Surfactants
Lubricants - esters
Dyes
Germicides
35
J i Ç. .
232
SPECIFIC INDUSTRIAL PROBLEMS
ing (he body part over a worktable or surface contaminated with fiber. The
airborne concentration of fibers in most work situations is low. Obviously,
there are exceptions, but good housekeeping practices ore useful in reducing fiberglass irritation. Such practices should be Instituted before recommending industrial hygiene ventilation or personal protective measures.
REFERENCES
]
Konzeo J . L : Observations of fibrous glass in relation to health in Zcoz C. (ed.):
Occupational M a f l d n * Principle» and Practical Applications. Chicago. Year
Book Medical Publisher», 1075.
2 Hcisel E.B., Juot F.E.: Further studies in cutaneous reactions to glass b b e n .
Arch. Enotiwi. Health 17:705-711. 1978.
3. Fossick P.A., Cellio C.A., Key M.M.: Fibrous gUsi dermatitis. Am. Ind. Myg.
Atwe.J. 31:12-15, 1970.
Chapter 26
Cutting Fluids, Oil, and
Lubricants
R J . Q. Rycrofl
WHEN HARD MATERIALS s u c h as m e t a l a r e c u t . s o m u c h h e a t is g e n e r a t e d
that a metal cutting too! can become welded to the metal being cut (workpiece). Metalworking Quids are therefore directed at the interface between
cutting tool and workpiece. By reducing friction and conducting away heat,
the fluid cools the cutting process.
There are three main types of metalworking fluids: neat oils, oil-ln-water
emulsions, and aqueous solutions. Neat oils may be of mineral, a n i m a t o r
vegetable origin and may contain wilur, chlorine, phosphorus, or other
additives to confer improved performance. Oil-ln-water emulsions are supplied as complex mixtures of mineral, animal, or vegetable oils, emulafiers
(surfactants), and other additives and are emulsified by the addition of water at the factory. Aqueous solutions have no emulsified oil content and
depend for their action on the combined effect of water and surfactants.
They also contain other additives. 1, *
Sldn exposure to neat (insoluble) oils has long been known to cause oil
aaie or t M ^ H " * and, when prolonged, hyperpigmentation. keratoses,
and cancer of the scrotum and other exposed skin. Edematous dermatitis,
rather than folliculitis, occasionally occur* and is usually irritant in etiology.
Allergens are added to neat oils, however, and, rarely, a case of allergic
contact dermatitis to a neat oil additive may arise. Recent examples in my
own experience include s e n s i t i z a t i o n to epoxide 7 and dipentene. add.t.ves
in grinding and honing oils. Because of the incidence of epithelioma from
mineral oil exposure, mineral oils used in metalworking fluids should all be
" c t t T f a m t e r f t m - H " " ' used for metalworking are commonly called "soluble oils." They contain not only emulsifiers, such as petroleum sulfonates
and carboxylic acid soaps, but also wnosion inhibitors phase stabibxers.
extreme pressure additives, antifoams. dyes, and microbioddes. Otf acne
seems not to occur, and keratoses and epithelioma are much rarer. In con233
234
C U T T M Q FLUIDS. O I L AND U B R I C A N T S
SPECIFIC INDUSTRIAL PROBLEMS
(rest, eczcmatous dermatitis is much commoner with soluble oils than with
neat oils. Aqueous solutions share this cferacterbtfc with soluble oils, and
many of their constituents are the some. ID machinists heavily exposed to
either type of water-based metalworking fluid,' prevalence rates of dermatitis us high as 30% can be found.
Patch testing of patients with soluble oil dermatitis is frequently negative
and the condition usually has all the characteristics of an irritant dermatitis.
Sometimes, however, sensitization can be detected to additives such as
ethylenediamine, mercaptobenzothiazole, formaldehyde, and other microbiocides. Constituents must be tested separately to establish such sensitivities. Tall oil products, containing colophony, are frequently part of the
emulsifier system, and positive patch test reactions to colophony may
therefore be relevant. Bacteria grow plentifully in soluble oils but are not
usually directly pathogenic to man. They may possibly have a role, however, in making a soluble oil more irritant, though this has not been
proved. The irritancy of soluble oils is not yet fully explained, but it is
likely to reside primarily in its combination of wetness, alkalinity and surfactant content.
Clinically, the early stages of soluble oil dermatitis may be characterized
by the appearance of a fine follicular erythema. This appears to be a follicular eczema rather than a pustular folliculitis as seen with neat oils. Later
stages of soluble oil dermatitis are characteristically patchy, papular eczemas, sometimes like discoid eczema in appearance, over the backs of the
hands or forearms. Vesicular palmar and finger eczema is rarely found in
soluble oil dermatitis and, when it is. can be associated either with allergic
sensitization or with an underlying endogenous eczema. The implications
of these clinical appearances in the etiology of soluble oil dermatitis are not
yet clear.
Recent speculation as to the connection between nitrosamines formed in
soluble oils, from combination between nitrites and amines, and skin cancer are too recent to be evaluated but are of considerable interest. The
formation of other condensation products and the metabolic products of
bacteria may, perhaps, also increase the irritancy of soluble oil in use. It
often appears that .long-used soluble oil is more irritant than fresh soluble
oil.
At our present state of knowledge of the etiology of soluble oil dermatitis. prevention is still far from satisfactory. It can best be thought of as
aimed in three directions: at the machine, the oil, and the man. Machines
should be designed to reduce the exposure of the operators' skin to metalworking fluid to a minimum. They should also be designed so that they are
easy to take apart and clean. Oil formulators should strive to avoid the
23S
inclusion of known irritants and allergens. Oil in use should lie kept us free
of fine particulates as possible and regularly changed. Selection of workers
is difficult, but clearly atopics should be advised against working with soluble oil. Early reporting of rashes should enable action to be taken at an
early stage to control any dermatitis that does arise. Men with early soluble
oil dermatitis sometimes manage to continue working and the rash gradually disperses.
If this does not occur, it is a reasonable plan to take them away from
soluble oil contact until the rash does clear. They may then return to work.
Should they have a further recurrence, then a two- to three-month break
from soluble oil contact is worth trying. A significant recurrence following
a prolonged break such as this is an indication that permanent removal
from soluble oil contact may have to be considered. Medicolegal considerations may interfere with this suggested scheme.
All cases of soluble oil dermatitis should, of course, be fully Investigated
by patch testing in the search for an allergenic cause (Table 26-1). If soluble oils are tested at their usage concentration, false negative results may
be obtained because of the overdilution of additives. If they are tested
undiluted, false positive reactions can occur because of the Irritant action
of the concentrate. The only reliable way out of this dilemma is to patch
test the chemical constituents of a soluble oil separately at appropriate concentrations.
At present the ultimate answer to soluble oil dermatitis appears to be
the ever-growing computer control of metalworking machinery. Meanwhile, there is a great need for manufacturers to reconcile more successfully the technical requirements of soluble oils with their dermatologie effects.
TABLE
28-1.—A
CURHENT METALWOAKINC F L U I D SERIES FOB
PATCH T E S T I N G *
CHEMICAL
TEST ACENT
CroUn Bit (hesahydro-t.3.S*(rlj(2-hydnuyethyl)-«-triaxine)
Cretan HD (N-melhyW-cbloraceUmtde)
1% Petrolatum
19 Petrolatum
1% Petrolatum
1% Petrolatum
1% Petrolatum
5* Olive oil
MEK
0.25» Petrolatum
1% Petrolatum
19 Petrolatum
0.254 Petrolatum
CMOIWTIMHTR
PanchbromeUmsol
Orthophenylpheooi
Pine oil
Dipentene
Epnfcle 7
l-H Betuotriazole
Bakzid 2
Katfaon MW
•To he uietl in conjunct km with i standard acrin.
Ann. Occup. Hyg. Vol. 14. pp. 181-190. Pergamoo Press 1971. Printed in Great Britain
MACHINE TOOL DESIGN A N D USE IN RELATION
C U T T I N G FLUIDS
TO
J. O . COOKSON
Machine Tool Industry Research Association, Hurdsfield, Macclesfield, Cheshire
INTRODUCTION
THE AIM of this paper is to give a description of the general situation with regard to
the use of cutting fluids with machine tools. It thus includes consideration of the
reasons for using cutting fluids of various kinds and the choice available to the
production engineer, between water-based and neat oils for example, because this is
relevant both to the action which can be taken in the workshop and to the design of
the machine tools.
There are about 1,000,000 machine tools of all kinds in use in this country.
These include a whole variety of metal-cutting machines such as lathes, milling,
drilling and grinding machines. On the majority of these machines provision is
made for the application of cutting fluids to the cutting zone. This is no new development, the first reference to the use of cutting fluids appears to be in a book on turning
(NORTHCOTT, 1868), but the number of applications and the varieties of cutting fluid
have increased enormously since then.
REASONS FOR USING CUTTING
FLUIDS
Cutting fluids are applied to the cutting zone to improve the efficiency of metalcutting operations by increasing the life of cutting tools, by improving the surface
finish on the workpiece, and by reducing cutting forces and the power required.
There are also secondary functions which may be of great practical importance in
particular machining operations:
Cooling the workpiece, to reduce expansion and distortion, and thus improve
the accuracy. Cooling can also make handling easier.
Cooling and washing away of the cut metal. Removing the swarf from the
working area of the machine can be very important on high-production machines.
Lubrication of exposed parts of the machine slides and other working parts.
Protection of the workpiece from corrosion. The newly-cut surface is clean and
likely to rust or tarnish unless a film of oil or corrosion inhibitor is put on i t
The achievement of the primary functions in the cutting zone may be explained
simply as a combination of the cooling and the lubricating properties of the cutting
fluid (COOKSON, 1970).
181
182*
J. O . COOKSON
TYPES OF CUTTING
FLUID
In practice the cooling and lubricating effects are obtained from fluids mixed in
water and from oil-based fluids respectively. Since the cooling effects of oils are much
less than those of water, efforts have been made to formulate fluids combining both
properties (SPRINGBORN, 1967). The cutting fluids in common use may be classified
as follows.
Water-miscible
Water-miscible fluids form mixtures varying in form from emulsions to solutions
when mixed with water in dilutions ranging from 1:5-1:50.
Soluble oils. In workshop terminology these may be called 'coolant', "suds1 or
'mystic* and are oil-in-water emulsions. In addition to the emulsifier, other materials
may be added to increase corrosion inhibition and resistance to attack by bacteria,
fungi or mould. The most common, soluble oil cutting fluids have droplets large
enough to reflect incident light and therefore appear opaque or milky. Usually a
range of soluble oils will be available; for example:
Emulsified oils based on a mineral oil with an emulsifier of petroleum sulphonates,
amine soaps, rosin soaps, naphthenic acids etc. The normal dilution for use is in the
range 1:10—1:50, depending on the application and the degree of lubrication required.
Translucent or clear emulsions with a lower oil content and larger amounts of
emulsifier which provide smaller oil droplets. These are used at low concentrations
(1:50 or 1:100) for operations in which observation of the cutting operation and
freedom from oiliness may be advantages, in grinding for example.
Super-fatted emulsions having animal or vegetable fats or oils or other esters
added to increase the lubrication properties.
Extreme pressure emulsions having sulphur, chlorine or phosphorous additives.
Synthetic fluids (ichemical fluids). These have been evolved in recent years to
complement or replace the existing range of soluble oils, and are formulated from
less conventional materials rarely described in detail in relation to commercially
available products. They are oil-less, and consist of dissolved materials including
additives which tend to form colloidal aggregates among the surface-active molecules.
The aggregates are smaller than emulsion droplets and thus the fluids are clear.
They may have lubricating properties which can be further improved by incorporating
sulphur, chlorine or phosphorous additives to give extreme pressure qualities. There
is thus a range of such fluids with varying properties and applications, as with soluble
oils. Some forms of superfatted oil emulsions (see above) may be referred to as semisynthetic (or semi-chemical) fluids, particularly in American literature.
Chemical solutions. These are oil-free aqueous solutions of basically inorganic
chemicals such as nitrites, borates, nitrates etc., perhaps with organic substances.
;
Machine tool design and use in relation to cutting fluids
ii 1 from fluids mixed in
" effects of oils are much
fluids combining both
• i use may be classified
emulsions to solutions
[,
îd 'coolant*, 'suds' or
i: .Isi fier, other materials
ice to attack by bacteria,
ds have droplets large
or milky. Usually a
petroleum sulphonates,
lution for use is in the
e f lubrication required.
r
-ind larger amounts of
at low concentrations
.. :utting operation and
<L..tple.
:>r oils or other esters
:>' <sphorous additives.
i
?d in recent years to
are formulated from
ation to commercially
d materials including
s face-active molecules,
ins the fluids are clear,
roved by incorporating
ssure qualities. There
'L.jtions, as with soluble
be referred to as semijrature.
ir
of basically inorganic
h organic substances
VS
183
such as amines to inhibit corrosion. They are clear but possibly coloured. In use
they are further diluted, usually about 1:50 or 1:100.
Neat cutting oils
These are cutting fluids which are solely oils, of petroleum, animal, marine or
vegetable origin, singly or in combination, with or without additives. They are used
undiluted. Some basic types include the following:
Straight mineral oils. These are uncompounded mineral oils, available in a range
of viscosities.
Blends of fatty and mineral oils. The properties of mineral.oils may be improved
by polar additives in the form of fats and oils which may be animal (e.g. lard oil),
vegetable (e.g. palm oil, castor oil) or marine (e.g. sperm oil). Some of these oils
have characteristic odours or tend to develop them as a result of oxidation or bacterial
action.
Sulphured fatty-mineral oils. To provide extreme pressure
sulphur may be added to the cutting oil by dissolving elemental
This sulphur is loosely held, is reactive at low temperatures
stain non-ferrous metals such as copper, brass and bronze
freshly-machined steel surfaces. This is termed an active oil.
lubricating properties,
sulphur in mineral oil.
and tends to severely
and, sometimes, even
Sulphurized
fatty-minerûl oils. Sulphur may also be added to a cutting oil as
sulphurized fat, formed by chemical reaction at much higher temperatures than the
sulphured mineral oil. The chemical bond is stronger, the active sulphur is not
released as readily and the oils may be totally non-staining. These oils are usually
blended with mineral oils..
Oils with sulphur and chlorine additives. Chlorine also functions as an extreme
pressure additive. It is usually added to mineral oil as a chlorinated wax or ester.
Frequently a sulpho-chlorinated additive is used in the form of a sulpho-chlorinated
mineral or "fatty oil and thus both mineral and mineral-fatty oil blends are available.
Chlorine functions in essentially the same manner as sulphur but reacts at a lower
temperature. It does not usually stain most non-ferrous metals.
The basic types of oils considered above do not include all the possibilities which
may be available commercially. Detailed formulations differ and the kind and
amounts of additives vary widely, as well as the proportions of fatty and mineral oils
in blends and the viscosity of the oils.
CHOICE OF CUTTING
FLUID
Water-miscible fluids are the most commonly-used, probably for some 80 per
cent of all machining operations, because they give a degree of combined cooling and
lubrication suitable for the majority of metal-cutting operations carried out at
higher speeds and lower pressures—general turning, milling, grinding, etc. In
184*
J . O . COOKSON
addition, they are more economical than neat oils because dilution with water brings
the cost down, and the working conditions are better, with cooler, cleaner parts,
reduction of oil mistingjmd fuming and a reduction in fire hazard.
Neat oils.have advantages-over water-miscible fluids when both good lubrication
and some cooling i^jre^iired to provide an economic tool life and a good surface
finish, especially when-usiiig high speed steel tools at moderate speeds and feeds;
and when the combination of a slower cutting speed and a requirement for low
surface roughness demands good lubrication. In operations such as broaching,
especially with difficult workpiece materials, the properties of the cutting fluid may be
vital to the success of the operation. On complex machines where exposed slides and
other parts are continually bathed in the cutting fluid, such as multi-spindle and some
single-spindle automatic lathes, neat oils are traditionally used to provide lubrication.
It is, of course, possible to, machine without a cutting fluid but tool life and
surface finish may be poor. However, cutting tools such as cemented carbides, are
frequently used to advantage without a cutting fluid. Some brittle materials, such as
grey cast iron, may be cut dry. In these cases the secondary functions of the fluid
may be the deciding factor in choosing whether to use a fluid—avoidance of dust,
removal of swarf, cooling the workpiece, etc.
THE APPLICATION OF CUTTING
FLUIDS
It is only by forcing a sufficient quantity of fluid into the cutting zone, the point
of contact between cutting tool and workpiece, that effective operation can be
assured. In single-point turning, for example, tool life can be shown to improve as,
the quantity of cutting fluid is increased up to 3 - 5 gal/min (TOURRET, 1958)/.
However, the proper delivery of anample flow directed through suitable nozzles to
the point of cutting is often neglected by machine operators (SPRINGBORN, 1967 ;
MORTON, 1959), sometimes, it must be admitted, because of the lack of adequateprovision for splash guards.
On self-contained machines the cutting fluid, after flooding the cutting area,
drains down over various parts of the machine, possibly to a collecting pan, and
thence to a sump or tank which may be either separate or form part of the machine
base (MORTON, 1969). The volume of the tank must be sufficient to allow time for
cooling and for the settling of fine swarf and may be from 5 or 10 gallons upwards,
to 50 gallons or more, depending on the type of machine. There is usually a coarse
strainer on top of the collecting pan to prevent the larger swarf from entering the
tank and a strainer at the pump suction, but many machines have no other filtering *
devices: Important exceptions are grinding, honing, lapping and deep-hole boring
machines where • high-quality work depends upon removing the finer swarf and
abrasive particles.
Groups of machines may be linked to a central system which can also handle the
swarf by means of an integrated conveying system of mechanical, hydraulic or
pneumatic type (GOUGH, 1970). This is only practicable if the machines are cutting
similar materials since the same cutting fluid is used throughout and, also, mixed
metals lose their scrap value. Some general advantages are the central control of the
Machine tool design and use in relation to cutting fluids
ition with water brings
cooler, cleaner parts»
h card.
both good lubrication
r
e and a good surface
•v ite speeds and feeds;
a requirement for low
s such as broaching,
: cutting fluid may be
v re exposed slides and
nulti-spindle and some
3 provide lubrication,
lid but tool life and
r
emented carbides, are
ittle materials, such as
jnctions of the fluid
u.^—avoidance of dust,
••DS
• tting zone, the point
:tive operation can be
shown to improve as
n (TOURRET, 1958).
suitable nozzles to
(SPRINGBORN, 1967 ;
ie lack of adequate
lH
ing the cutting area,
collecting pan, and
part of the machine
c.vnt to allow time for
10 gallons upwards,
: is usually a coarse
•v f from entering the
L
ive no other filtering
d deep-hole boring
he finer swarf and
i can also handle the
nical, hydraulic or
: -lachines are cutting
ut and, also, mixed
ntral control of the
804
V\
cutting fluid which ensures that its composition and dilution are correct, and that
bacteriological contamination can be controlled. The working conditions are
improved by the elimination of physical handling, particularly in the collection of
swarf wetted by cutting fluids, and gains will accrue from reduced labour, space and
operating cost.
WORKSHOP
HYGIENE
The hands and arms of machine operators are liable to be exposed to cutting oils,
and other parts of the body may be contaminated as a result of splashes from, or
contact with, the machine. There may also be exposure to oil fumes and oil mist.
The adjustment, setting-up and general operation of machines and the removal of
swarf are activities which bring people into contact with oil and users must be made
aware of the dangers which can be encountered from careless and indifferent handling.
Soluble oil emulsions provide a breeding ground for aerobic or anaerobic bacteria
and infected systems may develop considerable quantities of slimes, gums and
sludges—levels of 100 lb per 1000 gallons of emulsion are quoted (HILL, 1968). In
addition to health problems and foul odours, the performance of the cutting fluid
will be reduced and corrosion problems occur. The useful life of fluids can be reduced
to weeks instead of being months. The source of infection is invariably the residues
from previous changes of emulsion, so the simplest and most beneficial step is
effective draining, cleaning (both flushing with a chemical cleaner and physical
cleaning) and preferably sterilising between changes (SPRINGBORN, 1967; HILL, 1968).
Cases of industrial dermatitis can arise, especially amongst persons sensitive to
skin irritations, but a more fundamentally serious problem is the possibility of skin
cancer and, in particular, cancer of the scrotum. Detailed discussion is not needed
here since two other papers at this Conference are concerned with this subject
(WATERHOUSE, 1971; CATCHPOLE et al., 1971), but some of the steps which can be
taken in workshops to minimise the risks are listed below.
The reduction of initial exposure. Various features of machine tool design and use
which work towards this are discussed later in this paper.
The use of solvent-refined and soluble oils. It is believed that the use of cutting
oils from which carcinogens have been removed by solvent extraction during the
refining process will obviate or greatly reduce the hazard ( H . M . CHIEF INSPECTOR OF
FACTORIES, 1967). However, it will be many years before the statistics indicate conclusively whether the use of solvent-refined oils is completely successful in eliminating
the occurrence of skin cancer. In the meantime the use of soluble oils (solvent
refined) where technically feasible, would also be an important step in the right
direction.
Overalls. The provision of correctly designed protective clothing and a regular
laundry service for overalls reduces the wearing of oil-soaked clothing in continuous
contact with the skin.
Washing facilities. These are of great importance.
Warnings. Leaflets and posters exist which warn that mineral oil may cause
cancer of the skin ( H . M . FACTORY INSPECTORATE).
J. O . COOKSON
186*
T H E
USE
O F
C U T T I N G .
F L U I D S
O N
M A C H I N E
T O O L S
Water-mixed fluids can provide some lubrication with only a marginal loss of
cooling; they rarely, if ever, achieve the degree of lubrication available from neat
oils. However, there is an increasingly effective range of soluble oils and other
water-based fluids available and from the point of view of minimising the amount of
oil to which machine operators are exposed, it is well worth considering whether a
change away from a neat oil is technically feasible in particular cases ( S P R I N G B O R N ,
1967). Table 1 shows an estimate of the present overall position with regard to the
use of cutting fluids on the various types of machine tools.
M A C H I N E
D E S I G N
When a change from neat oil to a water-based fluid is contemplated, consideration
must be given to the suitability of the machine tool. Some machines have, in the past,
often been designed only for use with neat oils since they were expected to be used in
this way. The problems of lubricating the slideways and preventing ingress of water
to bearings and gearboxes are more difficult when soluble oil emulsions are used, but
the correct choice of materials for seals and care in design can alleviate the problem.
Many more machines of modern design can be expected to be suitable for use with
soluble oil emulsions, though higher standards of maintenance may be needed to check
the condition of the machine and the lubricating oil. It may sometimes be necessary
to draw-off water from lubricating oil sumps and to consider more carefully the
question of changing the lubricating oil. With precautions such as these, together
with accurate and continuous control of dilution to avoid corrosion, it is possible to
run some automatic lathes for many years on water-based cutting oils.
G U A R D S
If we look at modern machine tools it can be seen that there is a trend to enclose
more of the moving parts and working areas of the machine. This is necessary to
prevent the ingress of dust and metal particles and to prevent damage to sliding
surfaces as well as to provide for safety of the operator from moving parts and from
the metal removed in the form of swarf, as well as from the cutting fluid. Devices
for areas of the machine to which the operator does not need constant access include
bellows, gaiters, blinds and screens, metal telescopic covers and corrugated or folded
covers in a wide variety of moulded or fabricated sheet material (BEAKBANE and
WARING, 1967). Well-designed guards for the working areas of machines will incorporate a number of principles which can be summarized as follows:
Guards must be as robust as possible and rigidly supported where possible.
Guards which are not permanently fixed will be easily removed and, what is very
important, just as easily replaced. This often leads to the use of sliding guards.
If the guard obscures the view of the working area, shatter-proof windows will
avoid the temptation to leave the guard off.
Guards designed on an overlapping drip-proof principle have advantages over
sealed, abutting types.
Machine tool design and use in relation to cutting fluids
TABLE I .
187
N U M B E R S OF MACHINE TOOLS OF VARIOUS TYPES INSTALLED IN U . K .
RELATIVE USE OF WATER-BASED AND NEAT CUTTING OILS
Type of machine
No. of
machines
in U.K.
AND ESTIMATES OF
Machines operating
with
water- with
based
neat
dry
fluid
oil
( %)
( %) ( %)
Turning machines
Centre, surfacing, boring and toolroom lathes
Copying lathes
Multi-tool lathes
Turret lathes
Capstan lathes
Automatics
95.000
5800
7700
23,200
63,900
59,000
—
Threading machines
Including tapping, screwing, thread rolling and grinding
machines
26,600
—
Special & transfer machines
18.600
Mechanical power presses
Hydraulic & pneumatic presses
Vertical or horizontal, open front or straight sided ; single,
double and triple action
Boring machines
Horizontal boring, etc
Vertical boring mills
Fine borers
Jig borers
Broaching machines
Cut-off & sawing machines
Bandsaws
Abrasive disc
Hacksaw
Circular Saw
Drilling machines
Sensitive and bench, single spindle, multi.spindle, radial arm.
others (not special and transfer)
Deep hole
Gear cutting &. finishing machines
Grinding machines
All types of precision including tool and cutter but not thread
Bench, floorstand, snag and abrasive belt
Honing & lapping machines
Milling machines (except thread millers)
Planing & shaping machines
Polishing & buffing machines
10
I
90
85
80
75
85
20
14
20
20
15
80
20
80
5
60
35
70,200
30
30
40
157,000
20
20
60
12.200
7300
6000
5100
50
65
20
40
48
35
50
60
2
—
5300
5
20
75
10.500
4400
19,700
10,000
80.
20
75
55
90
25
4
—
40
25
75
—
5
41
10
30
185.000
2000
60
23,800
5
20
75
131,000
50,000
8
88
85
10
7
2
—
25
75
108,200
15
85
—
20,300
85
15
12,800
—
V\
188*
J. O . COOKSON
The cutting of apertures to allow for the passage of pipes or conduit should be
avoided:
The efficiency of existing guards may be judged on the basis of these principles
and modern machines can reach high standards. By the design of efficient guards
one hopes to contain the cutting fluid and swarf completely within the machine and,
as an illustration of the degree of success which may be achieved, at a major machine
tool exhibition it is possible to walk on to stands where machines are fully operational with cutting fluids, with no great fear of getting splashed.
ERGONOMIC DESIGN
The controls for machine tools are nowadays more likely to be designed according
to sound ergonomie principles, arranged for convenient operation. They are often
grouped in one place, remote electrical control allows more flexibility in design, so
that the operating position is predictable and precautions can be taken against
splashing. On the other hand, on some machines, the control panel may be moveable
and the operator can choose his own position.
AUTOMATION
The operator has other jobs to do besides push the stop and start buttons, which
may involve him in closer contact with the machine. However, the pressure of
technical development and higher productivity, particularly in respect of automatic
machines, reduces this contact to a minimum. The development of machine control
systems is such that automatic machines are used to produce much smaller batch
quantities than was formerly the case. Automation is not just for mass-production.
Increasingly, automatic loading is used for second-operation and chuck work.
Unloading, toÔ, may be completely mechanised but increasing attention is being
given, where this is not possible, to workcatchers and simple methods of delivering
the workpiece to a point conveniently accessible without moving the guards.
SWARF HANDLING
A frequent reason for operators needing to have access to the working area of the
machine is to deal with swarf. It is not unusual to see quantities of tangled bushy or
long stringy swarf being produced and the operator pulling at this with a hook,
sometimes while the machine is still running. This situation need not be tolerated.
A lot is now known about the way cutting tools produce swarf and they can usually
be designed to produce short manageable coils or curls. This is to the advantage of
everyone at all stages of swarf handling—even the scrap merchant will give a better
price'for compact swarf. Both drills and turning tools are available with built-in
chipbreakers and quite a lot has been written about the subject (PERCIVAL, 1968 ;
TEN HORN and SCHORMANN, 1953).
Machine tool design and use in relation to cutting fluids
>r conduit should be
v s of these principles
of efficient guards
t1 lin the machine and,
\ . „ at a major machine
icilines are fully opera-
(j e designed according
.•ration. They are often
xibility in design, so
; in be taken against
p«.iel may be moveable
189
I f the swarf can be induced to break, the cutting fluids will wash it down into a
collecting point in the machine and machine designers are increasingly aware of the
necessity to make sure that this can happen (GOUGH, 1970). On some high-production
machines swarf conveyors can be built into the base of the machine, lifting the swarf
into transportable bins or straight onto a conveyor.
PRE-SET T O O L I N G
Increasingly, production engineers are concerned to increase the time the machine
spends in cutting metal. One way is to reduce the setting-up times by the use of preset tooling. The effect of this is to change the working procedures of the operator or
setter by reducing the time which is spent adjusting tooling on the machine. The tools
are set-up in an area away from the machine, using fixtures and gauges, and are
expected to cut to the correct size when mounted as assembled units into the machine.
There is also an increasing use of planning techniques such as 'group machining1
which reduce the amount of tool changing by grouping similar workpieces for
machining in sequence.
CONTROL
i. start buttons, which
>wever, the pressure of
respect of automatic
t of machine control
ic. much smaller batch
" r mass-production.
>n and chuck work,
ti g attention is being
*» methods of delivering
•g the guards.
t : working area of the
•:*s of tangled bushy or
it this with a hook,
;ed not be tolerated,
irt and they can usually
s to the advantage of
int will give a better
...ailable with built-in
;ct (PERCIVAL, 1968 ;
%
One of the main changes in machine tool design over the past 10-15 yr has been
in the development of control systems. Increasingly, changes in the way machine
tools are controlled are eliminating the need for the setter to delve into the mechanism
of the machine and physically change cams and mechanised stops and to re-set the
positions of tools. The stop and trip bars or barrels, for example, can be interchangeable so that setting may be carried out away from the machine.
Changes in machine tool control systems to plugboard control, where the sequence
of operations is determined by changing electrical circuits by positioning plugs into
a control panel, or to numerical control by paper tape, are ways of providing automatically operated machines which require less attention from the operator. There
must now be many thousands of plugboard controlled machines, particularly of the
capstan and automatic lathe type and conversion kits are available for fitting to
existing machines. Tape-controlled machine tools are in the minority at the present
time, but their sphere of application is steadily increasing, including particularly the
application to lathes, while sophisticated manufacturing systems consisting of a group
of tape-controlled machines linked by conveyors along which a mixed collection of
workpieces may be routed are already available. During 1970, machine tool exhibitions have high-lighted the use of central computers to control considerable groups
of machines and developments such as these, which reduce even further the involvement of the operator, are certain to feature in the manufacturing methods of the
future.
CONCLUSIONS
This discussion may now have seemed to have reached a point rather far from
the consideration of cutting fluids, but, really, the point of much of the latter part of
this paper is that in addition to the conscious efforts of machine tool designers to
V \
J. O . COOKSON
190*
improve the working conditions of the operator, there are changes in machine tool
design and use taking place now—under the pressure of economic and technical
factors—which will have effects welcomed by those who have concern for the improvement of working conditions. This means that although there are some immediate
problems to be tackled, there is very real evidence of the improvements to come as
new machines and methods are adopted.
REFERENCES
BEAKBANE, H. R. and WARING, R. H. (1967) Machine Toot Protection. Queen Anne Press. London.
CATCHPOLE, W . M . , MACMILLAN ELIZABETH a n d POWELL. H . (1971) Ann. occup.
COOKSON, J . O . ( 1 9 7 0 ) Engineering
210, 557.
Hyg.
14.
GOUGH. P. J. C. (1970) Swarf and Machine Tools. Hutchinson, London.
H.M. Chief Inspector of Factories (1967) Annual Report. Department of Employment and Productivity, H.M.S.O., London.
H.M. Factory Inspectorate
SHW 367 Cautionary notice on dermatitis.
SHW 295 Leaflet 'Effects of oil on the skin'.
SHW 295A Leaflet 'Cancer of the skin caused by oil*.
SHW 397 4Effects of mineral oil on the skin*.
HILL, E. C . (1968) Tribology 1, 157.
MORTON, I. S. (1959) Scient. Lubric. 11, 39.
MORTON I S (1970) Lubrication and coolant systems for machine tools. Proc. Symp. Industrial
Lubrication & Tribology, London, 1969. Scientific Publications (G.B.) Ltd., Broseley, Shropshire.
NORTHCOTT, W . H . (1868) A Treatise
PERCTVAL, N . (1968) Metalwkg.
on Lathes
and Turning,
_
.
f
Longman Green, London.
Prod. 1 1 2 , 3 6 .
.
.
..
SPRINGBORN, R. K. (1967) Cutting and grinding fluids: selection and application. American bociety
of Tool and Manufacturing Engineers. Michigan.
TEN HORN, B. L . a n d SCHORMANN, R . A . (1953) Microtechnic
9, I .
TOURRET, R. (1958) Performance of metal cutting tools. Butterworth, London.
WATERHOUSE, J. A . H . (1971) Ann.
occup.
Hyg.
14.
m à
NOMENCLATURE
LIST OF TABLES
T a b l e 1-1
T a b l e 1-2
Density, V o l u m e t r i c Specific H e a t , T h e r m a l C o n d u c tivity, a n d Viscosity of Selected Fluids
Effect of V a r i o u s C u t t i n g Fluids in L o w e r i n g t h e
Table III-l
T a b l e IV-1
Tool-Workpiece Temperatures Measured When
M a c h i n i n g Steels
Fluids f o r Use at Sub-Ambient T e m p e r a t u r e s
R e c o m m e n d a t i o n s f o r C u t t i n g a n d G r i n d i n g Fluids
Table
Table
Table
Table
Table
IV-2
IV-3
V-l
VIII-1
VIII-2
Table
Table
Table
Table
Table
Table
VIII-3
IX-1
IX-2
IX-3
IX-4
IX-5
a n d Application M e t h o d s
C u t t i n g a n d G r i n d i n g Fluid C o d e s
Application M e t h o d s
R a t i n g s o f D e g r e e of Separation o r T u r b i d i t y
E l e m e n t s of T o t a l M a n u f a c t u r i n g Costs
C u t t i n g a n d G r i n d i n g Fluid Justification —
Cost W o r k Sheet
E x a m p l e s of T o t a l Systems Costs
M a c h i n i n g O p e r a t i o n Problems
G r i n d i n g O p e r a t i o n Problems
M a i n t e n a n c e Problems
Physiological Problems
Economic Problems
14
19
51
54
64
65
86
122
124
125
138
140
141
144
145
O v e r (he years, j a r g o n e n t e r s into any technology a n d various names arc
given to h e m s a n d systems peculiar to that technology. Many different names
for t h e same thing a r e correct, but interchangeable usage is confusing. Metalw o r k i n g fluids a r e n o exception; a single type of fluid is called by many names.
T o clarify this situation a n d to m a k e any p a n of this book u n d e r s t a n d a b l e to I lie
r e a d e r , the following n o m e n c l a t u r e will be used t h r o u g h o u t :
A) C h e m i c a l F l u i d s (sometimes called "Synthetic Fluids").
1) True solutions — Clear ( t r a n s p a r e n t ) but possibly colored, consisting of
inorganic a n d / o r materials dissolved in water as shown in Fig. A. The
dissolved materials may be considered to be r a n d o m l y dispersed within
the solvent water molecules. Usually, s u r f a c e tension is not much lower
t h a n plain water. T h e p r i m a r y f u n c t i o n of t r u e solutions is to inhibit rust.
T h e y usually have low lubricating value.
l
2) Surface-active t\f>e — A water solution of (I) containing additives which
lower ihe s u r f a c e tension of water a n d t e n d to f o r m colloidal aggregates
(micelles) a m o n g t h e surface-active molecules as shown in Fig. 11. Fluids
a r e <|uiu' clear l>v casual inspection a n d have good lubricating <|iialitics.
A
o
o
A
o
A
A
1
A
O
A
MOLECULE OF DISSOLVED MATERIAL
«ATER MOLECULE
»x
o
A fv
A A
o
A A,
o
Fig. A.
P i c t o r i a l r e p r e s e n t a t i o n o f true
I
solutions.
NOMENCLATURE
NOMENCLATURE
I m p r o v e d lubricating o r e x t r e m e pressure (EP) qualities a r e provided In
i n c o r p o r a t i n g s u l f u r , c h l o r i n e , o r p h o s p h o r u s additives.
B) E m u l s i o n s ( c o m m o n l y called "Water Miscible Fluids," s o m e t i m e s " W a t e r
Soluble Oils" o r "Emulsifiable C u l l i n g Fluids"). A .suspension of oil d r o p l e t s
(mineral, pur.itlinic, o r n a p h t h e n i c base oils) in water. Made by b l e n d i n g t h e oil
with e m u l s i f y i n g a g e m s a n d o t h e r materials so thai oil d r o p l e t s of 0.0002 in. (o
0 . 0 0 0 0 8 in. in d i a m e t e r f o r m when mixed with water (see Kig. (').
T h e addition of animal o r vegetable fats or oils o r o t h e r esters produces
" s u p e r - f a t t e d " emulsions of g r e a t e r lubricating value.
T h e addition of s u l f u r , chlorine, o r p h o s p h o r u s p r o d u c t s produces fluids of
even g r e a t e r lubricating value. These a r e o f t e n designated as e x t r e m e pressure
(EP) emulsions.
Fig. D.
Fig. B.
Pictorial representation of
stirjace-active
3,
Pictorial representation of semi-chemical fluids.
type.
Çr*
0
Fig. C.
Pictorial representation of emulsions.
Fig. E.
s
= PETROLEUM. ANIMAL. MARINE. OR
VEGETABLE OIL OR FATS
* ADDITIVE MOLECULE
Pictorial representation of cutting oils.
m à
NOMENCLATURE
LIST OF TABLES
T a b l e 1-1
T a b l e 1-2
Density, V o l u m e t r i c Specific H e a t , T h e r m a l C o n d u c tivity, a n d Viscosity of Selected Fluids
Effect of V a r i o u s C u t t i n g Fluids in L o w e r i n g t h e
Table III-l
T a b l e IV-1
Tool-Workpiece Temperatures Measured When
M a c h i n i n g Steels
Fluids f o r Use at Sub-Ambient T e m p e r a t u r e s
R e c o m m e n d a t i o n s f o r C u t t i n g a n d G r i n d i n g Fluids
Table
Table
Table
Table
Table
IV-2
IV-3
V-l
VIII-1
VIII-2
Table
Table
Table
Table
Table
Table
VIII-3
IX-1
IX-2
IX-3
IX-4
IX-5
a n d Application M e t h o d s
C u t t i n g a n d G r i n d i n g Fluid C o d e s
Application M e t h o d s
R a t i n g s o f D e g r e e of Separation o r T u r b i d i t y
E l e m e n t s of T o t a l M a n u f a c t u r i n g Costs
C u t t i n g a n d G r i n d i n g Fluid Justification —
Cost W o r k Sheet
E x a m p l e s of T o t a l Systems Costs
M a c h i n i n g O p e r a t i o n Problems
G r i n d i n g O p e r a t i o n Problems
M a i n t e n a n c e Problems
Physiological Problems
Economic Problems
14
19
51
54
64
65
86
122
124
125
138
140
141
144
145
O v e r (he years, j a r g o n e n t e r s into any technology a n d various names are
given to items a n d systems peculiar to (hat technology. Many different names
for t h e same thing a r e correct, but interchangeable usage is confusing. Metalw o r k i n g fluids a r e n o exception; a single type of fluid is called by many names.
T o clarify this situation a n d to m a k e any part of this book u n d e r s t a n d a b l e to the
r e a d e r , the following n o m e n c l a t u r e will be used t h r o u g h o u t :
A) C h e m i c a l F l u i d s (sometimes called "Synthetic Fluids").
1) True solutions — Clear ( t r a n s p a r e n t ) but possibly colored, consisting of
inorganic a n d / o r materials dissolved in water as shown in Fig. A. The
dissolved materials may be considered to be r a n d o m l y dispersed within
the solvent water molecules. Usually, s u r f a c e tension is not much lower
t h a n plain water. T h e p r i m a r y f u n c t i o n of t r u e solutions is to inhibit rust.
T h e y usually have low lubricating value.
l
2) Surfuce-uctive t\/je — A water solution of (I) containing additives which
lower the s u r f a c e tension of water a n d t e n d to f o r m colloidal aggregates
(micelles) a m o n g t h e surface-active molecules as shown in Fig. 11. Fluids
a r e <|uiir clear l>v casual inspection a n d have good lubricating <|iialitics.
A
o
o
A
o
A
A
1
A
O
A
MOLECULE OF DISSOLVED MATERIAL
«ATER MOLECULE
»x
o
A fv
A A
o
A A,
o
Fig. A.
Pictorial representation of true solutions.
I
NOMENCLATURE
NOMENCLATURE
I m p r o v e d lubricating o r e x t r e m e pressure (EP) qualities a r e provided in
i n c o r p o r a t i n g s u l f u r , c h l o r i n e , o r p h o s p h o r u s additives.
B) E m u l s i o n s ( c o m m o n l y called "Water Miscible Fluids," s o m e t i m e s " W a t e r
Soluble Oils" o r "Kmulsiftable C u l l i n g Fluids"). A .suspension of oil d r o p l e t s
(mineral, paratlinic, o r n a p h t h e n i c base oils) in water. Made by b l e n d i n g t h e oil
with e m u l s i f y i n g a g e n t s a n d o t h e r materials so thai oil d r o p l e t s of 0.0002 in. (o
0 . 0 0 0 0 8 in. in d i a m e t e r f o r m when mixed with water (see Fig. (').
T h e addition of animal o r vegetable fats or oils o r o t h e r esters produces
" s u p e r - f a t t e d " emulsions of g r e a t e r lubricating value.
T h e addition of s u l f u r , chlorine, o r p h o s p h o r u s p r o d u c t s produces fluids of
even g r e a t e r lubricating value. These a r e o f t e n designated as e x t r e m e pressure
(EP) emulsions.
Fig. D.
Fig. B.
Pictorial representation of
stirjace-active
3,
Pictorial representation of semi-chemical fluids.
type.
Çr*
0
Fig. C.
Pictorial représentation of emulsions.
Fig. E.
s
= PETROLEUM. ANIMAL. MARINE. OR
VEGETABLE OIL OR FATS
* ADDITIVE MOLECULE
Pictorial representation of cutting oils.
4
NOMENCLATURE
C) S e m i - C h e m i c a l F l u i d s (sometimes called "Semi-Synthetic Fluids"). Essentially a c o m b i n a t i o n of types (A) a n d (B), but with t h e following additional c h a r acteristics:
.
I ) Lower oil c o n t e n t (e.g., 10 p e r cent to 45 per cent) t h a n type (B) fluids.
2) H i g h e r c o n t e n t of emulsifying o r surface active molecules t h a n type (B).
resulting in smaller average oil d r o p l e t d i a m e t e r s (see Fig. D). T h e s e
materials can be plain, " s u p e r fatted," o r e x t r e m e p r e s s u r e (EP) types.
D) C u t t i n g O i l . A c u t t i n g fluid which may be a n oil of p e t r o l e u m , animal,
m a r i n e , o r vegetable origin, either singly o r in combinations. T h e p e t r o l e u m oil
mav vary in s o u r c e s u c h as n a p h l h e n i c o r paraffinic, a n d in r a n g e of viscosity
f r o m verv low to very h i g h , d e p e n d i n g u p o n t h e i n t e n d e d application.
T h e a d d i t i o n of a n i m a l , m a r i n e , o r vegetable oils (fatty oils) increases t h e
wetting action of t h e p e t r o l e u m oil blend a n d improves t h e lubricating qualities,
particularly at h i g h e r t e m p e r a t u r e s .
C h l o r i n e , s u l f u r , o r p h o s p h o r u s additive agents can be i n c o r p o r a t e d (see
Fig. E) to i m p r o v e lubrication effects at even higher t e m p e r a t u r e s a n d p r e s s u r e s
t h a n that possible with p e t r o l e u m oils alone o r combinations of p e t r o l e u m oils
a n d fatly oils.
CHAPTER U
HOW FLUIDS FUNCTION
Metal cutting, practiced in s o m e f o r m since ancient limes, assumed great
i m p o r t a n c e d u r i n g t h e last 200 years as m a c h i n i n g played a m a j o r role in the
industrial revolution. T h e use of cutting fluids c a m e instinctively to early machinists, who applied lubricants by flooding t h e cutting area to reduce friction
a n d heal g e n e r a t i o n .
T h e first publication on c u t t i n g fluid applications a p p e a r s to be a book by
N o r t h c o u who, in 1868, r e p o r t e d that lathe productivity could be materially
increased by this m e a n s (1). Since that time, t h e economic advantages of an increasing variety of c u t t i n g fluids have grown steadily.
But, a l t h o u g h v o l u m e , types, a n d applications of cutting a n d grinding fluids
have kept pace with indusirial d e v e l o p m e n t , a f u n d a m e n t a l u n d e r s t a n d i n g of
how they work has followed very slowly, particularly in the area of apparent
lubrication effects in low-speed cutting. An early worker in 1881, Mallock,sensed
p a r t of a perennial mystery w h e n h e wrote, "Lubricants seem to act by lessening
t h e friction between t h e face of t h e tool a n d t h e shaving, it is difficult to see
how it gets there. P e r h a p s into t h e substance of t h e shaving"(2). Only by intensive research d u r i n g t h e last 3 0 years have this a n d s o m e related questions been
given reasonably satisfactory answers; yet o t h e r f u n d a m e n t a l difficulties remain
unsolved.
Detailed discussions of t h e application, composition, a n d selection of cutting
a n d g r i n d i n g fluids a p p e a r in C h a p t e r s 2, 3, a n d 4. T h e scope of this chapter is
limited to a discussion of t h e "why" a n d "how" of t h e cutting fluid's basic role.
T h e differential significance of several possible m e c h a n i s m s of fluid action is
e x a m i n e d u n d e r various m a c h i n i n g conditions. A n interpretation is made which
suggests that each of t h r e e m a j o r m e c h a n i s m s a r e valid a n d interdependent.
T h e i r relative i m p o r t a n c e differs with various fluids a n d with changes in application technique.
BASIC CONSIDERATIONS
T h e two m a j o r effects of c u t t i n g a n d g r i n d i n g fluids—cooling a n d lubricat i o n — a r e best accomplished by water-based a n d oil-based fluids, respectively.
H O W FLUIDS FUNCTION
CHITTEB
FLUID TYPES
F. W. Taylor (I) was one of the first to prove ihè practical value of using
liquids to aid in metal cutting. In 1883, he demonstrated that a heavy stream of
water, flooding the tool/chip/work piece contact area during cutting, increased
cutting speed by 30 to 40 per cent. The early findings of Taylor and others led
to the development and use of fatty oils for all types of metal cutting.
Further improvements followed quickly. Mineral oils were developed for
machining brasses and other non-ferrous alloys, and for light operations on
steel. Mineral oil and lard oil blends proved effective for the more difficult cutting operations, and met machining requirements at that time.
However, the demand for increased production accompanying the spread
of industrialization spurred efforts to increase cutting speeds and develop cutting tool materials of greater hardness and toughness than were presently
available. The development of such tool materials created a corresponding need
for improved cutting fluids. To meet this need, extensive research on the part of
fluid manufacturers and users alike, produced special chemical additives and
other means to impart the combinations of qualities required by heavy duty
machining.
Today, many blends and compounds provide cutting and grinding fluids
for every modern machining requirement. They may be a straight mineral oil,
or a mixture of oils, and may contain one or a combination of additives such as
sulfur, chlorine, phosphorus, or other chemicals: In addition, the emulsifiable
or water miscible oils are widely used. Mixed with water, they form emulsions
for use in machining and grinding where the primary need is for a moderate
coolant rather than a lubricant. More recendy, water miscible fluids using less
oil (or no oils) and based on chemicals with or without surface active agents, have
provided industry with products of even greater heat conducting properties for
still higher machining rates. Developments incorporating extreme pressure and
oiliness additives give cutting fluids the necessary properties for application to a
wide variety of machining operations.
The result of a great deal of research and development is that, today, no
cutting or grinding operation need be hindered by a lack of a proper fluid. Each
of the types of fluids available to the metalworking field is described in the sec-
32
FLUID TYPES
lions below. Their compositions, functions, advantages, and disadvantages are
discussed.
CUTTING OILS
33
CUTTING OILS
Unfortunately, ihe melting point of this film is rather low and its toughness
is limited. Therefore, in very severe operations, it must be further supplemented
by the use of extreme pressure additives such as sulfur and chlorine. Fig. 2-3
shows an extreme pressure sulfurized polar organic molecule (oleic acid).
A plain cutting oil is an oil derived from petroleum, animal, marine, or vegetable origin, used straight or in combination.
Mineral O i l s
The straight uncompounded mineral oils used in their natural state or as a
component of cutting and grinding fluids can be divided into two general categories: naphthenic mineral oils and paraffinic mineral oils. Basically the naphthenic mineral oils have saturated, ring-type structures; the paraffinic mineral
oils are straight or branched chain saturated hydrocarbons.
The application of both the naphthenic and the paraffinic mineral oils in a
straight, uncompounded form is restricted to very light-duty applications on
metals of high machinability such as aluminum, magnesium, brass, and sulfurized or leaded free-cutting steels. They are satisfactory only as hydrodynamic
or fluid-film type lubricants and must be compounded with surface reactive
additives if they are to be used as boundary or extreme pressure lubricants.
While straight mineral oils are still used to some extent as cutting oils, their
primary f unction is as a blending medium or a carrier of additives in both cutting oils and water miscible fluids. When used as such, the naphthenic oils are
preferable to the paraffinic because ihey aid in obtaining a more homogeneous
compound. Compared with naphthenic, the paraflinic oils have superior resistance to oxidation and deterioration at high temperatures, but they are not
as easily miscible with additives.
Polar Additives. These are oils, fats, certain waxes, and synthetic materials
which are added to mineral oils to increase their load-carrying capacity or cutting capabilities. The fats, fatty oils, waxes, etc., may be of animal, vegetable, or
marine origin. They find many uses in both water miscible and oil-phase cutting fluids. In cutting oils, they may be dispersed as is, or they may be reacted
with sulfur- and/or chlorine-bearing chemicals, then dispersed in the carrier oil.
In water miscibles, they are most often used in the form of soaps and fattyamine or amide condensates.
Many synthetic polar additives are also used in cutting fluids as partial boundary lubricants. Some of the most common are esters, condensates or fatty oils
and fatty acids, and poly or complex alcohols.
The function of any fat or oil polar additive is to wet and penetrate the
chip/tool interface by reducing the interfacial tension between the carrier mineral oil and the metal. This is accomplished by polarity or affinity of the polar
additive for the metal substrate. The heat generated by the metal removal causes
the absorbed film to react with the substrate metal, and the polar materials are
converted to a low-shear organo-metallic him. This film provides lubrication by
reducing the friction at the chip/tool interface. In essence, it acts as a partial
boundary lubricant. Fig. 2-1 shows the actual chemical structure of a saturated,
non-polar hydrocarbon; Fig. 2-2 shows an unsaturated polar organic molecule
(oleic acid).
Fig. 2-1.
Non-polar hydrocarbon. (Cour-
tesy. Muster Chemical
Corporation)
Fig. 2-2. Unsaturated polar organic
molecule (oleic acid). (Courtesy, Master
Chemical
Corporation)
Fig. 2-3. Extreme pressure additivesulfurized oleic acia. (Courtesy. Master
Chemical
Corporation)
Because of their affinity for a metallic surface, the polar additives are also
valuable as corrosion inhibitors. They lay down a tenacious "polar film" which
offers a "barrier" of protection to the atmosphere. Although the metallic soap
film does supply some boundary or extreme pressure lubrication, it is the least
effective of the commonly-used extreme pressure lubricants. This is due primarily to its relatively low melting point.
Animal. Animal fats and oils used as polar additives are derived from the
fatty tissue of such animals as cattle, sheep, and swine. Due to their unsaturated
chemical structure, the oils remain in liquid form at room temperature. The
fats, however, are "saturated," and remain solid or semi-solid at room temperature. Both the fats and oils are good boundary lubricants and can contribute to
the reduction of frictional heat in cutting or grinding operations.
34
FLUID TYPES
A n i m a l f a i s a n d oils t e n d l o d e v e l o p d i s a g r e e a b l e o d o r s d u e t o o x i d a t i v e a n d
b a c t e r i a l r a n c i d i t y . H o w e v e r , t h e i r susceptibility l o this p r o b l e m c a n b e g r e a t l y
r e d u c e d by c o r r e c t i v e c h e m i c a l p r o c e s s i n g a n d t h e use of g e r m i c i d a l a d d i t i v e s .
Vegetable. V e g e t a b l e oils a n d f a t s u s e d a s p o l a r a d d i t i v e s a r e o b t a i n e d by
c r u s h i n g a n d r e n d e r i n g t h e kernels, seeds, a n d whole f r u i t o f specific plants.
T h e r e s u l t i n g oils a r e l i q u i d a n d c o n t a i n a c e r t a i n p e r c e n t a g e of u n s a t u r a t e d fat.
V e g e t a b l e oils a r e d i v i d e d i n t o t w o c a t e g o r i e s : drying a n d ium-drying oils. T h e
d r y i n g t y p e f o r m a t o u g h elastic film w h e n e x p o s e d t o t h e a t m o s p h e r e f o r a n y
l e n g t h of t i m e d u e t o o x y g e n a b s o r p t i o n . T h e d r y i n g c h a r a c t e r i s t i c s o f s o m e oils,
h o w e v e r , is d u e l o t h e h i g h p e r v e n t a g e o f u n s a t u r a t e d f a t t y a c i d s w h i c h t h e y
contain.
T h e n o n - d r y i n g v e g e t a b l e oils c o n t a i n t h e leasi a m o u n t of u n s a t u r a t e d f a t s
a n d will nut f o r m t h e t o u g h elastic film w h e n e x p o s e d t o t h e a t m o s p h e r e .
B e c a u s e of t h e i r " d r y i n g p r o p e r t i e s " a n d t e n d e n c y t o g u m , t h e u n s a t u r a t e d ,
d r y i n g - t y p e v e g e t a b l e oils m u s t be f u r t h e r p r o c e s s e d b e f o r e t h e y c a n b e u s e d a s
l u b r i c a n t s , o r 10 m a k e s o a p s in c u l l i n g fluids. T h e n o n - d r y i n g t y p e v e g e t a b l e oils,
s u c h a s p a l m oil, c o c o n u t oil, a n d c a s t o r oil, b e c a u s e o f t h e i r low d e g r e e o f u n s a t u r a t i o n , d o n o t s u f f e r f r o m this d r a w b a c k a n d a r e u s e d e x t e n s i v e l y in t h e
m a n u f a c t u r e of c u l l i n g fluids a n d o t h e r l u b r i c a n t s .
Marine. T h e p o l a r a d d i t i v e s o f m a r i n e o r i g i n ( f a t t y t i s s u e o f fish, w h a l e s ,
a n d o t h e r m a r i n e animals) a r e liquids which exhibit a high d e g r e e o f u n s a t u r a l i o n . T h e o n e n o t a b l e e x c e p t i o n t o this is s p e r m oil, a f a t t y l u b r i c a n t d e r i v e d
f r o m t h e s p e r m w h a l e , w h o s e d e g r e e o f u n s a t u r a t i o n is v e r y s i m i l a r t o t h a t o f
m a n y a n i m a l f a t t y oils. S p e r m oil is o n e of t h e most p o p u l a r " l u b r i c a n t s " o f
m a r i n e o r i g i n u s e d in c u t t i n g fluids t o d a y . H o w e v e r , it is a c t u a l l y a l i q u i d w a x
r a t h e r t h a n a f a t t y oil. It is a n e x c e l l e n t b o u n d a r y l u b r i c a n t a n d is h i g h l y resist a n t t o g u m m i n g a n d viscosity d e c r e a s e w h e n s u b j e c t e d t o h i g h t e m p e r a t u r e s
and pressures.
T h e m a r i n e oils a r e g o o d b o u n d a r y l u b r i c a n t s a n d o f f e r a h a n d l i n g a d v a n t a g e l i e c a u s c of t h e i r l i q u i d f o r m . H o w e v e r , t h e y all h a v e a c h a r a c t e r i s t i c " f i s h y "
o d o r a n d m u s t b e t r e a t e d t o r e d u c e o r e l i m i n a t e this o d o r b e f o r e t h e y a r e industrially acceptable.
C h e m i c a l A d d i t i v e s . T o p r o d u c e a c c e p t a b l e p a r t s e c o n o m i c a l l y f r o m diffic u l l - t o - m a c h i n c m e t a l s , t h e p o l a r a d d i t i v e s u s e d in c u t t i n g oils m u s t b e s u p p l e m e n t e d with m o r e effective b o u n d a r y o r e x t r e m e p r e s s u r e lubricants which
p r o v i d e t o u g h e r , m o r e s t a b l e solid film l u b r i c a t i o n . T h i s s u p p l e m e n t a r y e x t r e m e
p r e s s u r e l u b r i c a t i o n is f u r n i s h e d by a d d i n g lo t h e c a r r i e r , s u b s t a n c e s w h i c h
contain reactive s u l f u r , chlorine, o r p h o s p h o r u s c o m p o n e n t s .
W h e n s u b j e c t e d t o t h e t e m p e r a t u r e s f o u n d at t h e c h i p / l o o 1 i n t e r f a c e , t h e
sulfur-, chlorine-, o r sulfur- and chlorine-bearing e x t r e m e pressure lubricant
a p p a r e n t l y r e a c t s l o e f f e c t : ( I ) l o w e r c u t t i n g f o r c e s , (2) r e d u c t i o n of c h i p thickness, a n d ('4) i m p r o v e d f i n i s h .
Prior to extensive research devoted to d e t e r m i n i n g (he exact mechanism of
r e a c t i o n , g e n e r a l o p i n i o n was t h a t a l o w - s h e a r - s i r e n g l h metallic s u l f i d e o r c h l o r i d e film w a s f o r m e d at t h e c h i p / t o o l i n t e r f a c e a n d tool flank/cut s u r f a c e i n t e r face so t h a t l o w e r e d f r i c t i o n r e d u c e d t h e t e n d e n c y t o w a r d f o r m a t i o n o f t h e
b u i l t - u p e d g e . T o d a y , h o w e v e r , g r e a i e r a c c e p t a n c e is b e i n g g i v e n t o t h e t h e o r y
t h a t t h e s u l f u r , c h l o r i n e , o r p h o s p h o r u s m a y possibly r e a c t f a v o r a b l y , n o t o n l y
o n t h e s u r f a c e of t h e c h i p , but also internally to a d e p t h sufficient to r e d u c e
35
C U T T I N G OILS
f o r c e s in t h e s h e a r z o n e so t h a t i h e c o m b i n e d e f f e c t s of c h e m i c a l reactions (both
i n t e r n a l a n d e x t e r n a l ) will m a r k e d l y r e d u c e f o r c e s in b o t h a r e a s . T h e total e n e r g y
r e d u c t i o n c a n b e as m u c h as 5 0 t o 8 0 p e r c e n i . H e n c e , e x t r e m e p r e s s u r e lubric a n t s c a n h e l p c o n t r o l i h e b u i l t - u p e d g e , i m p r o v e finishes, a n d h e l p t o c o n t r o l
tool life.
Sulfur. S u l f u r m a y b e a d d e d t o t h e c u t t i n g oil in t h e f o r m o f a s ul f u n zed
m i n e r a l oil o r a s u l f u r i z e d f a t . S u l f u r i z e d m i n e r a l oils a r e p r e p a r e d by simply
dissolving e l e m e n t a l s u l f u r in h o t m i n e r a l oil. S u l f u r i z a t i o n of f a t s r e q u i r e s
m u c h h i g h e r t e m p e r a i u r e s t h a n s u l f u r i z a t i o n of m i n e r a l oils, since t h e latter is
m e r e l y a m a i l e r o f d i s s o l u t i o n while t h e c o m b i n i n g o f s u l f u r with a fatty oil is
an e x o t h e r m i c , c h e m i c a l r e a c t i o n . T h i s r e s u l t s in a s t r o n g e r c h e m i c a l b o n d bet w e e n t h e fatty oil a n d t h e s u l f u r a t o m .
B e c a u s e m o r e e n e r g y is r e q u i r e d t o s u l f u r i z e a f a t i h a n to dissolve s u l f u r in
m i n e r a l oil, m o r e e n e r g y is r e q u i r e d t o b r e a k t h e s u l f u r away f r o m t h e fatty oil
so t h a t it r e a c t s at t h e c h i p / t o o l i n t e r f a c e d u r i n g t h e c u t t i n g o p e r a t i o n . F o r this
r e a s o n , t h e s u l f u r i z e d m i n e r a l oil is m o r e "active" at l o w e r t e m p e r a t u r e s t h a n
t h e s u l f u r i z e d f a t i y oil. H o w e v e r , s i n c e t h e t e m p e r a t u r e s ai t h e c h i p / t o o l interface f a r exceed t h e t e m p e r a t u r e s r e q u i r e d to p r o d u c e either a sulfurized mineral oil o r a s u l f u r i z e d f a t , t h e d i f f e r e n c e is o f litile c o n s e q u e n c e in relation to
their comparative effectiveness.
T h e s t a i n i n g t e n d e n c i e s o f c u t t i n g oils c o n t a i n i n g s u l f u r i z e d e x t r e m e press u r e l u b r i c a n t s v a r y widely in r e l a t i o n to t h e t y p e of s u l f u r i z e d c o n s t i t u e n t s they
c o n t a i n . B e c a u s e t h e s u l f u r dissolved in a m i n e r a l oil is very loosely h e l d , it is
very r e a c t i v e at low t e m p e r a t u r e s a n d t e n d s t o s l a i n severely n o n - f e r r o u s metals
such as c o p p e r , b r a s s , a n d b r o n z e . I n s o m e cases it will a l s o stain a f r e s h l y - m a c h ined steel s u r f a c e . I n c o m p a r i s o n , t h e f a t t y oil w h i c h h a s b e e n s u l f u r i z e d at
h i g h e r t e m p e r a t u r e s will n o t r e l e a s e active s u l f u r as r e a d i l y a n d , t h e r e f o r e , has
less t e n d e n c y t o stain n o n - f e r r o u s m e t a l s o r steel.
A c t u a l l y , it is possible t o m a n u f a c t u r e sulf u r i z e d f a t t y m a t e r i a l s t h a t will not
stain a n y m e t a l s u n d e r a l m o s t a n y c o n d i t i o n s e n c o u n t e r e d in m a c h i n i n g a n d
g r i n d i n g o p e r a t i o n s . H o w e v e r , a c o m p l e t e l y n o n - s t a i n i n g oil is n o t a universal
r e q u i r e m e n t . O n m a n y o p e r a t i o n s , t h e m o r e active oils will p e r f o r m satisfactorily a n d , in m a n y c a s e s , at l o w e r cost.
Chlorine. C h l o r i n e a l s o f u n c t i o n s a s a n e f f e c t i v e e x t r e m e p r e s s u r e lubricant
in c u l l i n g oils. It is g e n e r a l l y i n c o r p o r a t e d in t h e c a r r i e r m i n e r a l oil as a longc h a i n c h l o r i n a t e d w a x , o r as a h i g h - m o l e c u l a r w e i g h t c h l o r i n a t e d e s t e r .
T h e c h l o r i n e a d d i t i v e is s o m e t i m e s i n t r o d u c e d i n t o c u t t i n g oils in c o m b i n a tion with s u l f u r as a s u l f o - c h l o r i n a t e d m i n e r a l oil o r a s a s u l f o - c h l o r i n a t e d fatty
oil. T h i s t y p e o f e x t r e m e - p r e s s u r e - b e a r i n g c o m p o n e n t is m a n u f a c t u r e d by reacting a molecule, c o n t a i n i n g both s u l f u r a n d chlorine at high t e m p e r a t u r e ,
with a c a r r i e r w a x , m i n e r a l oil, o r fatty oil. C h l o r i n e r e a c t s a n d f u n c t i o n s at t h e
c h i p / t o o l i n t e r f a c e a n d t h e tool flank/cut s u r f a c e i n t e r f a c e in essentially t h e s a m e
m a n n e r a s s u l f u r . H o w e v e r , it is m o r e reactive t h a n s u l f u r a n d b e g i n s to c o m bine w i t h t h e s u b s t r a t e m e t a l a t l o w e r t e m p e r a t u r e s (see Fig. 2-4). Usually chlorine-bearing
e x t r e m e p r e s s u r e l u b r i c a n t s will n o t stain m o s t n o n - f e r r o u s metals.
B e c a u s e o f t h e i r h i g h c h e m i c a l reactivity, c h l o r i n e - b e a r i n g e x t r e m e p r e s s u r e
l u b r i c a n t s a r e always c o m p o u n d e d w i t h i n h i b i t i n g o r n e u t r a l i z i n g i n g r e d i e n t s
to p r e v e n t c o r r o s i o n o f f e r r o u s s u r f a c e s d u e t o t h e r e l e a s e o f excessive a m o u n t s
rtf p A i r t n o r h l n r i n * i.>V»»»r» it
nnt
iirn
i n h * n rKlnrin>> f*r*t r i m p
36
FLUID TYPES
EMULSIFIED O I L S (WATER MISCIBLE)
into use as an e x t r e m e p r e s s u r e lubricant, corrosion of f e r r o u s s u r f a c e s was a
c o m m o n p r o b l e m . T o d a y , with t h e use of inhibitors a n d b e t t e r m a n u f a c t u r i n g
techniques, c h l o r i n e - b e a r i n g e x t r e m e p r e s s u r e lubricants a r e m u c h m o r e s u b i e .
circulated. T o be effective, t h e solid lubricant, which is dispersed in the carrier
oil, must r e m a i n u n i f o r m l y s u s p e n d e d . Constant u n i f o r m suspension is difficult
to achieve; t h e r e f o r e , t h e solid lubricant particle may precipitate a n d cause lined o g g i n g a n d dirty m a c h i n e tool surfaces.
M o l y b d e n u m disulfide is an e x a m p l e of a c o m m o n solid lubricant. It has a
Hat laminar s t r u c t u r e which readily a d h e r e s t o metal surfaces t o f o r m a coaling
which provides good f r i c t i o n - r e d u c i n g properties. In a d d i t i o n , u n d e r t h e heat
and p r e s s u r e of t h e c u t t i n g o p e r a t i o n , t h e s u l f u r held in t h e disulfide molecule
combines to f o r m a low s h e a r - s t r e n g t h , e x t r e m e p r e s s u r e metallic sulfide film.
37
EMULSIFIED OILS (WATER MISCIBLE)
Fig. 2-4. Relative effectiveness of chlorine and sulfur in reducing friction at various
temperatures.
Chemical reaction b e t w e e n t h e chlorine a n d t h e metal is restricted to t h e chip/
tool i n t e r f a c e w h e r e t h e t e m p e r a t u r e s a r e high, t h u s eliminating t h e corrosion
p r o b l e m s c r e a t e d by t h e acidic by-products given off by unstable, uninhibited
c h l o r i n e - b e a r i n g materials.
Phosphorus. W h e n a d d e d to t h e c a r r i e r mineral oil in t h e f o r m of an organic p h o s p h a t e o r metallic p h o s p h a t e , p h o s p h o r u s will p e r f o r m as a mild ext r e m e p r e s s u r e lubricant o r anti-friction additive. H o w e v e r , it is not as effective
in p r e v e n t i n g metal w e l d i n g as s u l f u r a n d chlorine because t h e p h o s p h i d e film
will break d o w n at lower t e m p e r a t u r e s t h a n t h e c o r r e s p o n d i n g sulfide o r chlor i d e film. P h o s p h o r u s is most effective in r e d u c i n g friction a n d wear. In addition, most p h o s p h o r u s - b e a r i n g e x t r e m e p r e s s u r e lubricants a r e non-staining
to most f e r r o u s a n d n o n - f e r r o u s metals.
C o m p o u n d e d C u t t i n g O i l s . T o meet the varying n e e d s of t h e metalworking
i n d u s t r y , c u t t i n g oil m a n u f a c t u r e r s sometimes use a c o m b i n a t i o n of t h e polar
a n d chemical additives d i s p e r s e d in a carrier mineral oil. T h e balance o r combination of additives used d e p e n d u p o n t h e r e q u i r e m e n t s of t h e c u t t i n g o p e r a tion a n d metal b e i n g processed.
A partial list of c o m p o u n d e d c u t t i n g oils available includes:
1)
2)
3)
4)
5)
6)
7)
Fatly-mineral oil b l e n d s
S u l f u r i z e d f a t t y - m i n e r a l oils
C h l o r i n a t e d fatty o r non-fatty mineral oils
S u l f u r i z e d m i n e r a l oils
S u l f o - c h l o r i n a t e d mineral oils
S u l f o - c h l o r i n a t e d fatty oil blends
Any of t h e above also c o n t a i n i n g p h o s p h o r u s , o t h e r metal salts, a n d
solid lubricants
8) Any c o m b i n a t i o n of any of t h e above
Solid L u b r i c a n t s . T h e solid lubricant type of e x t r e m e p r e s s u r e additive is
used to a very limited e x t e n t in c u t t i n g fluids, especially if t h e fluid is b e i n g re-
An emulsion is a suspension of oil droplets in water m a d e by blending the
oil with emulsifying a g e n t s a n d o t h e r materials. T h e addition of animal o r vegetable fats o r oils o r o t h e r esters p r o d u c e s " s u p e r - f a t t e d " emulsions of g r e a t e r
lubricating value. T h e addition of s u l f u r , c h l o r i n e o r p h o s p h o r u s p r o d u c t s
produces fluids of even g r e a t e r lubricating value which a r e e x t r e m e pressure
emulsions.
Water miscible fluids f o r m m i x t u r e s r a n g i n g f r o m emulsions to solutions
when mixed with water which, d u e to its high specific heat, high thermal conductivity, a n d high heat of vaporization, is o n e of the most effective cooling
media known. B l e n d e d with water, the water miscible fluids provide t h e combined cooling a n d lubrication r e q u i r e d by metal removal o p e r a t i o n s conducted
at'high speeds a n d lower pressures.
Water miscible fluids a r e available in many f o r m s a n d variations. Distinctions between t h e m a r e usually m a d e o n t h e basis of both a p p e a r a n c e a n d per*
f o r m a n t e . W h e n m i x e d with water, however, they can be classified o n an
j p pea ranee basis as urn nut I emulsions o r c he mi ail fluids, the latter of which is discussed in t h e following section.
T h e n o r m a l water miscible emulsion discussed in this section contains emulsified particles large e n o u g h to reflect almost all incident light a n d , t h e r e f o r e ,
appears o p a q u e o r "milky." Fig. 2-5 classifies t h e d i f f e r e n t water miscible
products a c c o r d i n g to ideal particle size.
Water miscible c u t t i n g fluids o f f e r t h e following advantages:
1) Reduction of heat —allowing h i g h e r c u t t i n g s p e e d s
2) C l e a n e r conditions
DECREASING
NORMAL EMULSION
PARTICLE
SIZE
SEMI CHEMICAL
CHEMICAL
PARTICLE SIZE
LARGER THAN
0.000004 IN.
P A R T I C L E SIZE
BETWEEN
0.000004 IN. AND 0.00000004 IN.
PARTICLE SIZE
SMALLER THAN
0.00000004 IN.
MOST NORMAL
CUTTING FLUID
EMULSIONS RANGE
FROM; 0.0002 IN. TOO 00008 IN.
COLLOID SOLUTION
PARTICLES
TRUE SOLUTION
MOLECULAR ANO
IONIC DISPERSOLDS
PARTICLES CAN SE
SEEN UNDER
ORDINARY MICROSCOPE
PARTICLES CAN BE
SEEN UNDER
ELECTRON MICROSCOPE
PARTICLES CANNOT
BE SEEN UNDER
MICROSCOPE OF
ANY KINO
Fig. 2-5.
Water miscible products classified according to ideal paruçle size.
38
FLUID TYPES
3) M o r e e c o n o m i c a l - d i l u t i o n with water brings application costs d o w n
4) B e l t e r o p e r a t o r acceptance—cooler, cleaner parts
5) I m p r o v e d health a n d safety b e n e f i t s - n o fire h a z a r d ; r e d u c t i o n of oil
misting a n d f o g g i n g
In c o m p a r i s o n t o straight c u t t i n g oils, t h e water miscible fluids p r o v i d e less
rust c o n t r o l a n d significantly decreased corrosion inhibition d u e to t h e introduction of water. W i t h i n t h e past 5 years, however, significant strides h a v e been
m a d e with t h e use of new, m o r e effective corrosion preventive additives. T h e
n e e d f o r "in-process c o r r o s i o n preventives" has b e e n r e d u c e d drasucally, and
several days to a week of corrosion inhibition can be e x p e c t e d o n m a n y applications.
B e c a u s e t h e viscosity of a water miscible fluid m i x t u r e , as u s e d , is almost
e q u a l to that of w a t e r , its i n h e r e n t film s t r e n g t h a n d lubrication p r o p e r t i e s are
i n f e r i o r t o t h o s e of most straight c u t t i n g oils. T h e i n h e r e n t viscosity of a straight
c u t t i n g oil s u p p l i e s " h y d r a u l i c c u s h i o n i n g " which helps to r e d u c e shock (especially o n an a b r u p t c u t t i n g o p e r a t i o n such as broaching) a n d r e d u c e s abrasive
wear. T h i s s h o r t c o m i n g in water miscible fluids is also a p p a r e n t in severe grinding o p e r a t i o n s such as f o r m , t h r e a d , a n d crush g r i n d i n g , w h e r e wheel form
m u s t be m a i n t a i n e d .
T h e soaps, wetting agents, a n d couplers used as emulsifiers in water miscible
fluids r e d u c e s u r f a c e tension significantly. With this r e d u c t i o n in s u r f a c e tension, a liquid b e c o m e s m o r e p r o n e to f o a m i n g w h e n subjected to s h e a r and
t u r b u l e n c e . F o r this r e a s o n , water miscible fluids s o m e t i m e s c a u s e a f o a m i n g
p r o b l e m in o p e r a t i o n s s u c h as gundrilling, flat-bed a n d double-disc grinding.
H o w e v e r , with t h e u s e of special welting agents a n d f o a m d e p r e s s a n t s , water
miscible fluids can be r e n d e r e d sufficiently n o n - f o a m i n g in almost all operations
t o be effective.
CHEMICAL AND S E M I - C H E M I C A L FLUIDS (WATER MISCIBLE)
extreme pressure additives a r e t e r m e d heavy-duty solubles a n d are capable, in
tome cases, of replacing cutting oils.
Fatty a n d e x t r e m e - p r e s s u r e - b e a r i n g water miscible fluids a r e used in rather
rich concentrations, such as o n e part oil to 5 to 15 parts water.
CHEMICAL AND SEMI-CHEMICAL FLUIDS (WATER MISCIBLE)
The clarity of both t h e chemical a n d semi-chemical solutions, when diluied
with waier, varies f r o m translucent to completely clear contrasted with the
"milky" o r o p a q u e emulsion f o r m e d by t h e n o r m a l mineral-oil-based water
miscible fluids. T h e chemical fluid is completely clear because its particle size
(see Fig. 2-6) is small e n o u g h to transmit o r allow almost all incident light to
COMPARATIVE DIMENSIONS OF OIL DROPLETS
SURFACE ACTIVE MOLECULE
EMULSION DROPLET
PARTICLE OF
CHEMICAL
COOLANT
FQ
0.000000)25 i
Fig. 2-6. Relative size of surface active
molecule compared with typical emulsion
droplets in a "soluble oil" mixture. (Courtesy, Master
Emulsified Mineral O i l s
T h e c o m m o n emulsified mineral oil contains a paraffinic o r n a p h t h e n i c
m i n e r a l oil generally r a n g i n g in viscosity f r o m 100 t o 500 sees, at 100°F. T h e
emulsifier may consist of p e t r o l e u m sulfonates, a m i n e soaps, rosin soaps, n a p h thenic acids, etc. P o p u l a r " c o u p l i n g " agents that assure stability in t h e base
l o r m a r e c o m p l e x alcohols a n d non-ionic wetting agents. O t h e r o r g a n i c polar
materials may b e a d d e d to increase c o r r o s i o n inhibition. Finally, germicides or
bactericides a r e o f t e n i n c l u d e d to resist attack by bacteria, f u n g i , o r m o l d a n d
e x t e n d e m u l s i o n life. N o r m a l use concentrations may r a n g e f r o m 2 to 10 p e r
ceni.
Highly-Fatted W a t e r Miscible Fluids
Fatty oils a n d fatty acids such as s p e r m oils, lard oil, esters, a n d o t h e r mixlures, a r e o f t e n a d d e d to emulsion concentrates to increase lubrication. T h i s
type of p r o d u c t is o f t e n used o n soft, stringy n o n - f e r r o u s alloys.
Extreme P r e s s u r e Emulsifiable Oils
S u l f u r , c h l o r i n e , a n d p h o s p h o r u s serve the s a m e f u n c t i o n in w a t e r miscible
p r o d u c t s as in c u l l i n g oils. Generally, water miscible c u t t i n g fluids c o n t a i n i n g
39
Chemicul
Corporation)
pass t h r o u g h . T h e solutions of i n t e r m e d i a t e particle size a r e classified as semichemical; these p r o d u c t s f o r m hazy o r slightly translucent emulsions.
Chemical Fluids
T h e chemical fluids a r e classified into t h r e e p r i m a r y types: (I) t r u e solution
type, (2) welting agent type, a n d (3) wetting agent type with e x t r e m e pressure
lubricant. T h o s e which f o r m a clear, t r a n s p a r e n t solution a r e water-based a n d
may contain inorganic materials such as borates, nitrites, nitrates, a n d phosphates f o r c o r r o s i o n inhibition, o r o r g a n i c materials such as amines a n d amides
for s u p p l e m e n t a r y protection. C o m p l e x alcohols a r e usually used as humectants.
Surface active agents a r e a d d e d to r e d u c e s u r f a c e a n d interfacial tension and
to p r o m o t e wetting a n d lubrication.
T h e m a n y such chemical p r o d u c t s now available fall into two general classes:
those with, a n d those without, wetting a g e n t s a n d g o o d lubricity. T h o s e with lubricity a n d wetting a g e n t s h a v e low s u r f a c e tension, g o o d rust-inhibiting p r o p e r ties, a n d leave a liquid residue. In n o r m a l operations, their slight tendency to
foam is not a factor of any c o n s e q u e n c e , b u t they may f o a m excessively when air
is beaten into t h e m , e.g., in disc-type s u r f a c e g r i n d e r s . T h e excellent lubricat-
40
FLUID TYPES
GASEOUS FLUIDS
ing qualities of chemical fluids allow machine slides, turrets, a n d o t h e r moving
parts to f u n c t i o n smoothly — a very i m p o r t a n t factor with increasing automation.
T h e g r o u p of chemical fluids without wetting agents usually d o not have
m u c h lubricity, a n d m a n y leave crystalline o r wax-like deposits u p o n evaporation of t h e water; this eventually interferes with m a c h i n e action. Many d o not
have e n o u g h lubricity t o d o t h e " t o u g h " j o b s a n d d o not p r o d u c e as g o o d a
finish in m a c h i n i n g a n d g r i n d i n g o p e r a t i o n s as d o t h e p r o d u c t s with g o o d lubricity characteristics. T h o s e chemical fluids without wetting agents usually d o
not " s c u m " in h a r d water.
bined with their ability to remain stable a n d nut float a mineral oil seal, generally
gives t h e m belter lank life t h a n t h e n o r m a l emulsion.
Chemical a n d semi-chemical fluids can be f o r m u l a t e d to provide verv good
wci "contact" corrosion control with the use of organic a n d inorganic inhibitors.
Products containing these inhibitors also exhibit relatively good protection f r o m
overall atmospheric corrosion. However, a n o r m a l water miscible fluid containing organic corrosion inhibitors, polar lubricants, a n d a high percentage of
mineral oil will give s u p e r i o r overall corrosion protection w h e n c o m p a r e d to
chemical. T h e fatty lubricants a n d mineral oil f o r m a " b a r r i e r " film o n the workpiece which provides an extra m e a s u r e of protection.
On the negative side, these disadvantages a r e sometimes e n c o u n t e r e d with
chemical a n d semi-chemical fluids:
1) Lack of lubrication "oiiiness" which may cause sticking in t h e moving
parts of m a c h i n e tools.
2) High d c t e r g c n c y may defat a n d irritate sensitive h a n d s where operator
e x p o s u r e is continual lor long p e r i o d s of time.
3) In c o m p a r i s o n to oils, less rust control a n d significantly decreased corrosion inhibition, inferior i n h e r e n t film s t r e n g t h a n d lubrication properties, a n d s o m e t e n d e n c y to f o a m .
S e m i - C h e m i c a l Fluids
T h e semi-chemical, unlike t h e chemical, fluids contain a small a m o u n t of
m i n e r a l oil plus additives to f u r t h e r e n h a n c e lubrication properties. T h e semichemicals a r e g a i n i n g f a v o r in industry today because they i n c o r p o r a t e t h e best
qualities of b o t h chemicals a n d n o r m a l water emulsions. Both chemical a n d
semi-chemical fluids a r e now available containing chlorine, s u l f u r , o r phosp h o r u s additives which a f f o r d e x t r e m e pressure o r b o u n d a r y lubrication effects.
Because of these additives, chemical o r semi-chemical fluids can be used o n s o m e
of t h e m o r e difficult m a c h i n i n g a n d g r i n d i n g applications. C o n c e n t r a t i o n r a n g e
may vary f r o m 2 to 10 p e r cent.
Advantages and Disadvantages
In g e n e r a l , t h e chemical a n d semi-chemical fluids o f f e r t h e following advantages:
1) Rapid heat dissipation a n d good size control
2) A high d e g r e e of cleanliness resulting in clean machine-tool surfaces
a n d clean coolant t r o u g h s
3) G o o d d e t e r g e n t p r o p e r t i e s which aid in the m a i n t e n a n c e of o p e n a n d
f r e e - c u l l i n g g r i n d i n g wheels
4) Kxccllenl work piece visibility
f>) Very light residual lilm which is easy to r e m o v e
G) Easy to mix with very little agitation necessary
7) Excellent resistance to rancidity a n d t h e r e f o r e g o o d tank life
8) Relatively easy c o n c e n t r a t i o n control with n o i n t e r f e r e n c e f r o m t r a m p
oils
The chemical a n d semi-chemical fluids both contain considerably less mineral oil t h a n t h e n o r m a l emulsifiable o r water miscible fluids. ( T h e " t r u e " synthetic o r chemical fluid contains no mineral oil.) In a d d i t i o n , emulsion particle
size is m u c h smaller as was shown in Fig. 2-5. T h e c o m b i n a t i o n of these two
factors p r o v i d e s t h e chemical a n d semi-chemical fluids with m u c h b e l t e r longt e r m stability t h a n t h e n o r m a l emulsion.
T h e g r o w t h of bacteria that results in spoiled n o r m a l emulsions is partially
ihe result of t h e activity of anaerobic bacteria which live a n d p r o l i f e r a t e most
rapidly u n d e r a n oil layer o r oil M seal" f o r m e d by a split e m u l s i o n . Emulsions
c o n t a i n i n g h i g h c o n c e n t r a t i o n s of fatty lubricants a n d emulsiflers u p o n which
this type of o r g a n i s m subsists a r e also m o r e susceptible. Generally, chemicals
a n d semi-chemicals c o n t a i n very little o r n o mineral oil o r o t h e r types of lubricants u p o n which a n a e r o b i c bacteria f e e d . T h e r e f o r e this characteristic, com-
41
GASEOUS FLUIDS
Gaseous fluids can p e r f o r m both cooling a n d lubricating functions. Some
gases will oxidize the newly-formed a n d chemically-clean chip, thereby preventing welding to the tool a n d r e d u c i n g friction. All gases provide cooling either
by convection, or when chilled to liquid f o r m , by vaporization.
Air
Air is t h e most c o m m o n l y used gaseous cutting fluid. It is t h e sole fluid constituent in " d r y " c u t t i n g a n d is also p r e s e n t , of course, when liquid fluids are
used. T h e cooling a n d lubricating action of air is taken f o r g r a n t e d because it
is always p r e s e n t .
Air can also !>c used as a c o m p r e s s e d gas to provide better cooling. A stream
of compressed " s h o p air" directed at t h e cutting z o n e r e m o v e s m o r e heat by
forced convection t h a n would o c c u r by n a t u r a l convection. In addition, compressed air can be used to blow chips away.
Gases for Special Applications
O t h e r gases have been used as c u t t i n g fluids but their high cost generally
makes t h e m uneconomical in p r o d u c t i o n except in very special applications.
T h e inert a n d semi-inert gases, such as a r g o n , h e l i u m , a n d nitrogen, have
been used to prevent t h e oxidation of workpiece a n d c h i p w h e r e unusual chemical p r o p e r t i e s a r e r e q u i r e d . T h e c u t t i n g a r e a is flooded with the gas to exclude o x y g e n but t h e gas must be a p p l i e d in a sealed c o n t a i n e r (such as a welding dry box) so that the c u t l e r d o e s not blow t h e gas away.
Gases with boiling points below r o o m t e m p e r a t u r e can be used as coolants.
Freon o r c a r b o n dioxide can be c o m p r e s s e d a n d sprayed at t h e cutting zone to
42
FLUID TYPES
give e v a p o r a t i v e c o o l i n g to t e m p e r a t u r e s well below 0°F. T h e use of liquid a r g o n
o r n i t r o g e n allows cooling to several h u n d r e d d e g r e e s below zero. Increases in
tool life can be e x p e c t e d f r o m all of these gaseous coolants, but their cost will be
e x t r e m e l y high.
&tre|)
MISCELLANEOUS FLUIDS
Frequently, in smaller s h o p s w h e r e safety a n d industrial hygiene rules are
not stringently e n f o r c e d , limited application of c a r b o n tetrachloride a n d tric h l o r o e t h a n e will be f o u n d . T h e s e a r e highly volatile, s h o r t - c h a i n e d hydroc a r b o n s c o n t a i n i n g a high c o n c e n t r a t i o n of chlorine. T h e s e materials wet well,
dissipate heal rapidly a n d , being relatively unstable, will p r o v i d e a metallic
c h l o r i d e s h e a r - s t r e n g t h r e d u c i n g effect at low t e m p e r a t u r e s . For these reasons,
they d o facilitate severe m a c h i n i n g o p e r a t i o n s o n difficult metals such as tapp i n g a n d t h r e a d i n g of 3 0 0 Series stainless steels a n d o t h e r heat-resistant alloys.
H o w e v e r , they a r e toxic if inhaled o r absorbed t h r o u g h t h e skin a n d , in addition,
will c a u s e skin d e f a t t i n g . A n o t h e r disadvantage is possible stress corrosion cracki n g o r f a i l u r e i n d u c e d by c o m p o n e n t s containing active c h l o r i d e ions. F u r t h e r ,
t h e s e fluids, a l t h o u g h p r o m o t i n g g o o d chip curl, cause tools to wear rapidly
with loss of size c o n t r o l , particularly in t a p p i n g operations.
REFERENCES
I. F. W. Taylor. On
the Art of Cutting Metals,
ASME, New York. New York, IUU6.
cm™
HOW CUTTINfi FLUIDS
ME APPLIED
T h e p r o p e r physical delivery of c u t t i n g fluids to t h e point of cut is o n e of the
most neglected aspects of p r o p e r c u t t i n g fluid application. Yet it is o n e of the
most i m p o r t a n t because, unless t h e fluid is carefully placed, it cannot p e r f o r m
its function. U n f o r t u n a t e l y , placement is o f t e n left to the o p e r a t o r , who, not
fully u n d e r s t a n d i n g t h e fluid's functions, places it f o r his personal convenience
rather t h a n f o r m a x i m u m effectiveness.
W h e n a fluid is chosen f o r its lubrication qualities, it must be directed so that
it can f o r m a film between t h e tool a n d work a n d chip. A good lubricating fluid
dribbled h a p h a z a r d l y o n t o t h e work piece prevents rust a n d lubricates the ways,
etc., but does not i m p r o v e t h e c u l l i n g process. T o obtain i m p r o v e d finish a n d
toot life, t h e fluid m u s t be directed to t h e place w h e r e these benefits occur: t h e
cutting e d g e of t h e tool.
Similarly, when a fluid is c h o s e n f o r its cooling properties, it must be directed
where cooling is r e q u i r e d — a t t h e c u t t i n g e d g e of t h e tool. While a general flow
over t h e workpiece d o e s h e l p to cool t h e work, it is only by f o r c i n g t h e fluid into
the cutting a r e a that heat can be r e m o v e d as it is g e n e r a t e d .
A c o m m o n e x a m p l e of t h e misapplication of a coolant is in surface g r i n d i n g
where t h e fluid flows o n t h e workpiece. H e r e , t h e g r i n d i n g wheel acts as a fan,
blowing t h e fluid away a n d p r e v e n t i n g it f r o m flowing in a n d cooling t h e grinding process.
A secondary a d v a n t a g e of g o o d fluid distribution design is t h e removal of
chips. P r o p e r placement of nozzles can p r e v e n t blockage o r packing of the chip
in the flutes of milling cutters a n d c o n s e q u e n t tool breakage. It can r e d u c e o r
eliminate t h e n e e d f o r b r u s h i n g o r blowing t h e chips away by h a n d labor a n d
remove t h e still-warm chips f r o m t h e w o r k i n g a r e a s of t h e machine.
T h e t e n d e n c y of h a r d a n d brittle cutting tool materials (such as carbide a n d
ceramic) t o crack when subjected to t h e r m a l shock can b e controlled by p r o p e r
design of t h e distribution system. Cyclic h e a t i n g a n d cooling of the e d g e produces m ic roc racks in t h e s u r f a c e which grow until small pieces of t h e e d g e break
away. As t h e e d g e c o n t i n u e s to c r u m b l e , p r e m a t u r e failure occurs. However,
properly placed nozzles, a r i n g d i s t r i b u t o r , o r a mist a p p a r a t u s can give continu-
<>4
t d t . ( / r r i . t - ' i u U^-v
S E L E C T I N G FLUIDS FOR M A C H I N I N G AND G R I N D I N G PROCESSES
3) Read t h e fluid a n d application r e c o m m e n d a t i o n s . R e f e r to fluid type and
application identification codes in Tables IV-2 a n d IV-3.
Multiple r e c o m m e n d a t i o n s a r e given to allow the u s e r g r e a t e r ease of matching r e c o m m e n d a t i o n s with his existing stock a n d suppliers' identifications, and
to cover t h e variations within the material a n d m a c h i n i n g o p e r a t i o n groupi
T h e p r e f e r r e d r e c o m m e n d a t i o n is given first, followed by o t h e r recommend*,
lions in d e s c e n d i n g o r d e r of p r e f e r e n c e . W h e r e a r a n g e of fluids is shown, e.g
3.1-3.12. all fluids within that r a n g e a r e r e c o m m e n d e d f o r t h e workpiece material a n d type of c u t i n d i c a t e d .
T a b l e IV-2. C u t t i n g a n d G r i n d i n g F l u i d C o d e s (3)
(:ode
Fluid T y p e
0
Dry
I1 I
1.2
Culling oils (A and B types)
Suiluri/ed oil*. light duty
Sulfuri/ed mineral-lard oil.
light duty
Sulltiri/cd mineral oil'", lighi duly
1-3
M
Suiluri/cd lard oil with chlorine,
light duly
1.5
Stall tii'i/ed oil. medium/heavy duly
l.t>
Sulfuri/ed mincral-lard oil,
medium heavy duly
1.7
Sulfuri/ed fat compounded oil.
utcdium/heavv duly
I.H
Su If mi/ed mineral oil. medium/
heavy duly
I.!»
Sulfuri/ed lard oil. medium/
heavy duty
I.ID Sulfo-chlorinated mineral-lard
oil. light duty
I.I I Siillo-rhlorinatcd mineral oil.
li^hi duly
1.12 Sulfo-chlorinalcd lard oil.
light duty
1.13 Sulfo-chlorinated mineral lard
oil, medium duty
1.14 Siillo-chlorinated mineral oil,
medium duly
1.15 Sulfo-chlorinated lard oil,
medium duly
l.lt> Sulfo-chlorinated oil, medium duty
1.17 Sulfo-chlorinated mineral lard
oil, heavy duty
I.IK Sulfo-chlorinaied lard oil,
heavy duly
I.Ml Sulfo-chlorinaied oil, heavy duty
1.20 Sulfo-chlorinaied mineral oil,
heavy duly
Code
1.21
Fluid T y p e
Highly chlorinated mineral lard
oil. heavy duty
1.22 Straight mineral oil
1.23 Straight oil
1.24 Mineral lard oil, medium
heavy duty
1.25 Mineral lard oil. light duty
1.20 Oil specialty recommended
aluminum and magnesium
1.27 Oil s|>ecialiy recommended
titanium alloys
1.28 Oil socially recommended
high-iem|M.Taiure alloys
1.29 Oil specially recommended
nickel base alloys
I.3U Oil specialty recommended
cobalt Ixise alloys
for
allim
lor
2.5
2.6
2.7
2.8
l«i
Fatty water miscible oil
Î 10 Extreme pressure water miscible
oil, heavy duty
2.11 Water miscible oil specialty recommended for titanium alloys
112 Water miscible oil specialty recommended for high nickel cobalt
alloys
Water miscible oil specialty recommended for stainless steel alloys
5.
Chemical fluids
3 1 Chemical emulsion, light duty
5 2 Water base chemical, light duty
3.3 Water miscible petrochemical.
light duty
5 4 Chemical emulsion, heavy duly
3.5 Sulfurizcd waier based chemical,
heavy duty
J.li Chlorinated waier based chemical,
heavy duty
3.7 Water miscible, heavy duty
Code
Fluid T y | i e
3.8
Chemical coolant
3.9
Chemical solution '
3.10 Chemical emulsion, oil base
3.11 Chemical and oil solution,
heavy duty
3.12 Chemical and organic compound
solution
3.13 Chemical with extreme pressure
and welling agent water miscible
3.14 Amine nitrite
3.15 5% sodium nitrite solution
3.16 M ineral oil base chemical
3.17 Chemical water mix compound
3.18 Chemical emulsion, heavy duly
3.1!» Chemical emulsion, medium duly
3.20 Chemical fluid specially for
non-ferrous alloys
3.21 Chemical fluid socially for
ferrous alloys
t h r e w o r p a r a l l i n k a n d t h e i r US|HHUVC c h e m i c a l r e a c t i v i t y will v a r y
Code
for
Honing oil
Tapping oil
Emulsifiable oils (water
miscible) all
Water miscible oil, lighi duty
Water miscible oil. medium duly
Water miscible oil. heavy duly
Sulfo-chlorinated waier miscible
oil, heavy duty
Chlorinated water miscible oil,
heavy duty
Sulfo-chlorinaied water miscible
compound, heavy duty
Water miscible compound, active
sulfur, heavy duty
Water miscible mineral oil
according!).
T a b l e IV-3. A p p l i c a t i o n M e t h o d s (3)
for
Oil s|>ccially recommended for
stainless sleel alloys
1.32 Chlorinated mineral laid oil
2.1
2.2
2.3
2.4
Fluid I > |»e
• I n t h e s e u M e s . t h e M i l l u r i r e d o i l » a n d s u l l u r i r c d m i n e r a l o i l » d i f l e t a s t o i h e s o u r c e * o f c r u d e » . T h e s e will b e n a p h -
lor
1.31
1.33
1.34
2.
T a b l e IV-2. C u t t i n g a n d G r i n d i n g F l u i d C o d e s (3) - C o n t ' d
Application
Flood (minimum of 3 gal./min./nozzle). Low pressure/high volume application to
cool tool and workpiece and supply Huid lo cutting zone. Flu.d should be directed
into the clearance angles of the cut. and completely envelop tool and workpiece U).
Nozzles on lathe lym- look should IK- at least V4 of the culling width, with the same
rati.» lor milling operations through the use of Ian no;/.les. On lace nulling, all uvth
should be immersed continuously, using ring distributor.
M Mist (waier miscible oils or chemical Huids). Uses air or aerosol-powered asperating
equipment to disperse Huid as very fine droplets in the carrier, which is then directed
at the culling area. Provides low volume and high velocity primarily used where
flood c o o l a n t application can not be utilized. Visibility of cut is increased with reduced
cooling of tool and workpiece. Added ventilation is recommended as well as aulomatic shut-oft'.
P High Pressure (50-2000 psi.). Pressure systems are used normally for internal appliation of Huid through drills, gundrills. end mills, and grinding wheels.
V High Velocity JeL Specialized application for increased penetration of fluid into cutting area. Creates considerable mist and smoke.
_
H Hand. Manual application of paste, solid, or liquid by brush, dipping, or oil can.
Immersion. Gravity or low pressure application by submerging workpiece in tank or
receptacle.
QQ
GEAR SHAPING
823 SELECTING FLUIDS FOR M A C H I N I N G AND G R I N D I N G PROCESSES
T h e g r o u p s of m a c h i n i n g o p e r a t i o n s included in T a b l e IV-1 a r e brieH\
described in t h e following sections (7). Typical m a c h i n i n g o p e r a t i o n s a n d / o r the
cutting a n d m a c h i n e tools which p e r f o r m these o p e r a t i o n s a r e illustrated.
TURNING
7!)
GROOVING
(Grooving is the process of m a c h i n i n g a recess in a revolving workpiece to a
specific d e p t h , width, a n d s h a p e . T h e single point tool, with p r o p e r groove configuration, f e e d s along a line p e r p e n d i c u l a r to t h e spindle axis (see Fig. 4-6).
A t u r n i n g o p e r a t i o n uses single point tools to g e n e r a t e o r cut a surface of
revolution —cylindrical, t a p e r e d o r c o n t o u r e d - i n a lathe, t u r r e t lathe, automatic b a r m a c h i n e , etc. T h e tool f e e d s into t h e rotating workpiece (see Fig. 4-3)
parallel to t h e axis of revolution of t h e s u r f a c e being cut.
WORKPIECE
c
TOOL
Fig. 4-6. Relationship of tool, workpiece, and feed in grooving operation.
FORMING
Fig. 4-3. Relationship of workpiece,
tool, and feed in a turning operation.
A f o r m i n g o p e r a t i o n cuts curved or irregular s h a p e s in t h e workpiece as the
workpiece revolves in a lathe as shown in Fig. 4-7.
BORINC
B o r i n g is i h e o p e r a t i o n used to e n l a r g e a hole 10 an exact size with a single
|M)int tool as illustrated in Fig. 4-4.
INTERNAL
•ORKPIECE
BORING BAR AND TOOL BIT
Fig. 4-4.
Relationship of lools, work pieces, and feeds in a boring operation.
Fig. 4-7. Relationships of tools, workxes, and feeds in external and internal
forming operations.
TOOL
FACING
CUTOFF
Facing is t h e t e r m u s e d to describe c u t t i n g of a flat s u r f a c e as t h e workpiece
revolves in a lathe in o r d e r to square t h e e n d with the sidies, o r r e d u c e t h e stock
to a d e s i r e d l e n g t h . The single point tool f e e d s along a line p e r p e n d i c u l a r to the
spindle axis (see Fig. 4-5).
T h e cutoff o r p a r t i n g o p e r a t i o n is similar to t h e facing o p e r a t i o n , except
that t h e cut is m a d e completely t h r o u g h t h e workpiece severing o n e end. A
cutoff tool is used similar to that shown in Fig. 4-8.
•ORKPIECE
FEED
>7"
TOOL
Fig. 4-5. Relationship of tool, workpiece,
and feed in facing o|>eration.
•ORXPIECE
Fig. 4-8. Relationship of tool, workpiece, and feed in cutoff operation.
69
7!)
S E L E C T I N G F L U I D S FOR M A C H I N I N G AND G R I N D I N G PROCESSES
GEAR SHAPING
End Milling
BOX TURN
T h e box t u r n t u r r e t l a t h e o p e r a t i o n is similar to t h e t u r n i n g o p e r a t i o n except t h e tool(s), c u t t e r h o l d e r , a n d steady rest c o m p r i s e o n e unit (see Fig. 4-9).
T h e steady rest travels with t h e tool, s u p p o r t s the work, a n d holds t h e work
against tool.
BOX TOOL
BOX TOOL AND STEADY REST
End mills a r e cylindrical in s h a p e a n d a r e provided with a shank for mounting a n d driving. T h e y have straight o r helical teeth o n t h e circumferential surfaces as shown in t h e various o p e r a t i o n s illustrated in Figs. 4-13 t h r o u g h 4-20.
Fig. 4*9. Relationship of box tool and
steady rest to workpiece and feed in box
turn turret lathe operation.
TREPANNING
RADIAL
DIMENSION
T h e t r e p a n o p e r a t i o n uses a single point tool (see Fig. 4-10) to p r o d u c e a hole
by m a c h i n i n g a c i r c u m f e r e n t i a l groove parallel t o t h e axis of r o t a t i o n , cutting
a cylindrical p a t h a n d leaving a solid core. T h i s core passes t h r o u g h t h e hollow
cylindrical c u t t i n g h e a d as t h e tool f e e d s into t h e metal. T r e p a n n i n g is unlike
the drilling o p e r a t i o n which r e d u c e s t h e metal to chips.
Fig. 4-15. Open end mill slotting (vertical machine).
Fig. 4-14.
machine).
Slab end milling (vertical
Fig. 4-10. Trepanning tool.
MILLING
Milling is t h e r e m o v a l of metal by m e a n s . o f a r o t a t i n g c u t t e r having o n e or
m o r e c u t t i n g e l e m e n t s called flutes o r teeth which, t o g e t h e r with t h e workpiece,
a r e held in a milling m a c h i n e . T h e c u t t e r r o u t e s while t h e work f e e d s u n d e r the
c u t t e r in o r d e r to r e m o v e t h e m e u l .
Face Milling
AXIAL
0IMENSI0N
fig. 4*15. Open end mill slotting (horitontal machine).
Fig. 4-16. Slab end milling (horizontal
machine).
.
In lace milling, m e u l is r e m o v e d by t h e c u t t i n g e d g e s located o n t h e corners
a n d p e r i p h e r y of t h e c u t t e r . Face mills a r e designed to mill flat s u r f a c e s normal
to their axis o f rotation as shown in Figs. 4-11 a n d 4-12.
(PI
Fig. 4-11.
tion.
Common face milling opera-
Fig. 4-12.
operation.
Shallow
shoulder
milling
Fig. 4-17.
End mill facing.
Fig. 4-18.
End mill shoulder cutting.
£
70
S E L E C T I N G FLUIDS FOR MACHINING AND GRINDING PROCESSES
7!)
GEAR SHAPING
Slot Milling
A slot mill is a combination side milling c u t l e r a n d e n d mill because it has
teeth on each side, as well as o n t h e p e r i p h e r y (see Figs. 4-24 a n d 4-25).
AXIAL
DIMENSION
R• V
' COTTER DIAMETER
Fig» 4-19. End mill boring or drilling to
nlake a blind slot.
Fig. 4-20.
End mill profile slab cutting.
AXIAL
DIMENSION
RADIAL
DIMENSION
Slab Milling (Plain Milling)
T h e slab mill is a c y l i n d e r with teeth cut a r o u n d t h e p e r i p h e r y only. It prod u c e s a flat s u r f a c e parallel to its own axis as illustrated in Figs. 4-21 a n d 4-22.
Fig. 4-24.
Slotting.
Fig. 4-25.
Small slotting.
Formed Milling Cutters
Formed cutters i n c o r p o r a t e cam-relieved teeth which a r e s h a r p e n e d by
grinding t h e tooth fat es a n d thereby maintain t h e original f o r m t h r o u g h o u t the
life of the cutler. F o r m e d cullers p r o d u c e i r r e g u l a r o r circular surfaces. Types
of f o r m e d milling c u i i e r s ' i n c l u d e convex, concave, c o r n e r - r o u n d i n g , gear looth
cutters, multiple t h r e a d mills, a n d hobs. Typical cuts a r e shown in Figs. 4-26
and 4-27.
« •
Fig. 4-21.
ile parts.
Slab mill used for facing frag-
DIAMETER
OF CUTTER
Fig. 4-22. Slab mill used for machining
cuts requiring a larger radius than could
be achieved by a radius ground on any
type cutter.
Side Milling
A side mill has a relatively n a r r o w face a n d has teeth o n o n e o r both sides as
well as ui, t h e p e r i p h e r y (see Fig. 4-2»). It is used f o r m a c h i n i n g o p e n slots, side
milling s h o u l d e r s , a n d s t r a d d l e milling.
Fig. 4-26. Typical convex form cuts made by corner rounding, corner rounding end
mUls. and concave cullers.
AXIAL
DIMENSION
Fig. 4-23.
Side milling.
Fig. 4-27. Typical concave form cuts made by convex and full radius cullers.
73
S E L E C T I N G FLUIDS FOR M A C H I N I N G AND G R I N D I N G PROCESSES
7!)
GEAR S H A P I N G
Milling Saw
A mill saw is essentially a thin plain milling cutter (teeth cut a r o u n d t h e periphery only) that p r o d u c e s a Hat s u r f a c e parallel to its own axis (see Fig. 4-28)
a n d has t h e sides d i s h e d to t h e cutting e d g e s t o provide tooth relief. It is used
f o r cutoff work or milling very n a r r o w slots.
Hollow Milling
A hollow mill is a c u t t e r of t u b u l a r construction (see Fig. 4-29) having teeth
o n o n e e n d a n d internal clearance. It is used f o r sizing cylindrical stock o r mac h i n i n g straight e n d s of work.
1ft
u
AXIAL
DEPTH
Fig. 4-28.
OIL CARRYING CHIPS OUT
r - n
IRAOIAL
DEPTH
CUT TING EDGE
7TT77777TTTT
Mill sawing.
Fig. 4-29.
Hollow mill.
Thread Milling
«ORKPIB'CE
A t h r e a d milling c u t l e r is a rotary cutting tool having teeth which intermittently e n g a g e t h e work piece (see Fig. 4-30) to cut internal o r e x t e r n a l threads
of a specific f o r m .
Fig. 4-32.
A gun drill is essentially a single-point end cutter similar to a boring cutter.
COUNTERBORING
$
w
Fig. 4-30. Thread milling cutter.
T h e c o u n i e r b o r i n g o p e r a t i o n enlarges a previously f o r m e d hole for part of
its d e p t h , usually to p r o d u c e a s h o u l d e r at t h e bottom of t h e e n l a r g e m e n t . A
guide o r pilot (see Fig. 4-33) assures concentricity of t h e original hole with ihe
enlarged p o r t i o n . W h e n t h e c o u n t e r b o r e d p o r t i o n is shallow, the operation is
called spot facing.
DRILLING
Drills a r e a n e n d c u t t i n g tool (see insert, Fig. 4-31) having o n e o r m o r e culling e d g e s a n d i n c o r p o r a t i n g helical o r straight flutes f o r t h e passage of cutting
fluid a n d c h i p s w h e n p r o d u c i n g a hole.
GUNDRILLING
Gundrills a r e used t o drill holes 5 o r m o r e times the drill d i a m e t e r in d e p t h .
A guiidrill is a single lip straight flute drill (see Fig. 4-32) h a v i n g a t u b u l a r stem
t h r o u g h which c u t t i n g fluid is f o r c e d to flush t h e chips o u t o f t h e flute. It is
normally held stationary while t h e work revolves. T h e g u n d r i l l provides exceptional accuracy, straightness, a n d a quality of s u r f a c e finish not otherwise
obtainable. .
Fig. 4-33. Counter bore and pilot.
SPOT FACING
T h e s p o t f a c i n g o p e r a t i o n cuts a circular spot below a s u r f a c e in a plane perpendicular to t h e axis of a hole t h r o u g h t h e spot. Spot facing a n d c o u n t e r b o r i n g
tools a r e e n d c u t t i n g tools.
74
S E L E C T I N G FLUIDS FOR M A C H I N I N G AND GRINDING
PROCESSES
7!)
GEAR S H A P I N G
COUNTERSINKING
T h e c o u n t e r s i n k i n g o p e r a t i o n uses a tool with 2 beveled c u t t i n g elements
a n d 2 flutes (see Fig. 4-34) t o c o u n t e r s i n k holes f o r fasteners. T h e c u t t i n g action
is very similar to t h e drill.
REAMING
R e a m e r s a r e r o t a r y c u t t i n g tools that e n l a r g e a n d finish a previously formed
hole to a c c u r a t e d i m e n s i o n s . A r e a m e r is an e n d cutting tool usually having more
t h a n o n e c u t t i n g e l e m e n t a n d flutes along t h e longitudinal axis which form
teeth as well as g r o o v e s f o r t h e passage of cutting fluid a n d c h i p removal (see
Fig. 4-35). It is d e s i g n e d t o r e m o v e a specific a m o u n t of stock (i.e., a cutting
action, not a b u r n i s h i n g action) in o r d e r to m a k e the hole straight, smoothly
finished, a n d of precise d i m e n s i o n .
Fig. 4-36.
Broaching machine with
broach in place ready to pull through.
{Courtesy. Lockheed-California
Company)
Fig. 4-37. Horizontal pull-type broaching machine showing insertion of broach
prior to cutting internal hole. {Courtesy,
Lockheed-California
Company)
BROACHING
B r o a c h i n g j s ;i m c l ; i | c u U j n K o p e r a t i o n that combines both r o u g h i n g and
finishing a n d which r e m o v e s stock to precision limits with g o o d finish quality
faster t h a n a n y o t h e r k n o w n metal c u t t i n g process. O n e of t h e p r i m a r y reasons
f o r this is t h e d i f f e r e n c e in principle between t h e b r o a c h i n g tool a n d o t h e r metal
cutting tools (see Figs. 4 - 3 6 a n d 4-37). A l t h o u g h b r o a c h i n g c o m b i n e s r o u g h i n g
a n d finishing, n o individual broach tooth h a n d l e s both functions. Each successive tooth r e m o v e s only a p r e - d e t e r m i n e d a m o u n t of stock, a n d is in cutting
contact only a s h o r t time.
Fig. 4-38. T a p used as a cylindrical
thread cutting tool.
SINGLE POINT THREAD CUTTING
Single point t h r e a d i n g is accomplished using a single point tool o n a lathe or
lathe-type m a c h i n e (see Fig. 4-39) by a combination of rotary m o t i o n of the
workpiece a n d l o n g i t u d i n a l m o t i o n of the carriage.
Lockheed-California
Company)
CHASING (EXTERNAL THREAD CUTTING)
A t h r e a d i n g die (chaser) is a tool used to cut e x t e r n a l threads. It consists of
blades o r circular f o r m s m a d e in sets a n d positioned with holders in a die head
as shown in Fig. 4-40. It cuts simultaneously on m o r e t h a n o n e point of the outside surface. Die h e a d s a r e o f t e n spring-loaded a n d adjustable to release at
full d e p t h .
TAPPING (INTERNAL THREAD CUTTING)
A t a p is a cylindrical t h r e a d c u t t i n g tool with o n e o r m o r e c u t t i n g elements
having t h r e a d s of a d e s i r e d f o r m on t h e p e r i p h e r y as shown in Fig. 4-38. By a
combination of r o t a r y a n d axial motion, t h e leading e d g e cuts an internal t h r e a d
while t h e t a p derives its principal s u p p o r t f r o m the t h r e a d it p r o d u c e s .
Fig. 4-39. Single point tool thread-cutting
on conventional engine lathe. (Courtesy,
j
GRINDING
T h e g r i n d i n g process is a m e t h o d of m a c h i n i n g by abrasive wheels. G r i n d i n g
is the rapid c u t t i n g away of metal by millions of m i n u t e c u t t i n g edges passing
across t h e surface. T i n y grains of extremely h a r d materials c e m e n t e d together
in the s h a p e of a wheel act as t h e cutting edges. T h r o u g h fast revolution of the
wheel t h e grains r e m o v e chips so small that they a p p e a r as fine metallic dust.
77
S E L E C T I N G FLUIDS FOR M A C H I N I N G AND G R I N D I N G PROCESSES
GEAR SHAPING 7!)
T h e fineness of t h e cuts m a k e s g r i n d i n g an excellent finishing o p e r a t i o n for
r e m o v i n g small a m o u n t s of metal following o t h e r m a c h i n i n g processes.
In t h e second type, t h e relative r o t a t i o n of the b o r e a n d g r i n d i n g wheel is
(he same as in t h e first m e t h o d , e x c e p t that t h e workpiece is chucked in a revolving headstock (see Fig. 4-43). Both work a n d wheel revolve o n fixed axes.
The feed f u n c t i o n is a s s u m e d by t h e wheel which cuts radially to a pre-determined d e p t h as g r i n d i n g continues.
Surface Grinding
Plain s u r f a c e g r i n d i n g is accomplished by traversing t h e workpiece back and
f o r t h b e n e a t h t h e wheel o r by f e e d i n g t h e workpiece (or s o m e t i m e s t h e wheel)
across p e r p e n d i c u l a r l y to t h e direction of traverse! T h e s u r f a c e being g r o u n d is
parallel t o t h e axis of t h e g r i n d i n g wheel as shown in Fig. 4-41.
GRINDING « H E E L
Fig. 4-42.
cylinder.
Fig. 4-40.
Internal grinding where workpiece reciprocates along the length of the base or
Die head and chasers.
SPINDLE
PULLEY
•ORKPIECE
Fig. 4-43.
Internal grinding where workpiece is chucked in revolving headstock.
Centerless Grinding
,
Fig. 4-41. Flat-bed surface grinding
operation. (Courtesy. The Blanchard Machine Company)
Internal Grinding
T h e r e a r e two types of i n t e r n a l g r i n d i n g processes. I n t h e first, t h e workpiece r e c i p r o c a t e s a l o n g t h e length of t h e base o r cylinder as t h e wheel rotates
rapidly o n its axis (see Fig. 4-42) which, in t u r n , describes circles a b o u t t h e axis
of t h e c y l i n d e r b e i n g g r o u n d .
Centerless g r i n d i n g (see Figs. 4-44 a n d 4-45) uses two abrasive w h e e l s - t h e
grinding wheel which d o e s t h e cutting, a n d a regulating wheel which acts as a
Fig. 4-44. Centerless through-feed grinding. (Courtesy, The Cincinnati Milling Machine Company)
»
Fig. 4-45. Centerless infeed grinding.
(Courtesy, The Cincinnati Milling Machine
Company)
7!)
S E L E C T I N G FLUIDS FOR M A C H I N I N G AND G R I N D I N G PROCESSES
GEAR S H A P I N G
brake 10 p r e v e n t t h e w o r k p i e c e f r o m s p i n n i n g at the high s p e e d of t h e grinding wheel. T h e r o t a t i o n a l axis of t h e r e g u l a t i n g wheel is set at a slight angle to
t h e horizontal axis of t h e c u t t i n g wheel t o i n d u c e horizontal m o v e m e n t of the
workpiece. A w o r k rest b l a d e between t h e wheels keeps t h e c e n t e r of rotation of
the workpiece a b o v e a line b e t w e e n t h e c e n t e r s of the r e g u l a t i n g a n d grinding
wheels. T h i s i n s u r e s a t r u e - r o u n d cylinder, even t h o u g h t h e original workpiece
may have b e e n initially o u t - o f - r o u n d .
the tool a n d workpiece. T h e h o b b i n g m a c h i n e feeds t h e tool t h r o u g h or into the
workpiece. T h e culling e d g e s of t h e tool have a f o r m that will p r o d u c e the desired tooih f o r m on the workpiece. T h e c u t t i n g action is c o n t i n u o u s in o n e direction until t h e blank is finished.
78
Cylindrical Grinding
T h e cylindrical g r i n d i n g process is used f o r g r i n d i n g cylindrical o r tapered
work o n t h e o u t s i d e s u r f a c e only. T h e abrasive wheel revolves on a horizontal
spindle parallel to t h e work which rotates past t h e c u t t i n g face of t h e wheel.
Thread Grinding
T h r e a d g r i n d i n g is essentially cylindrical g r i n d i n g with a wheel s h a p e d accurately to t h e t h r e a d f o r m to be g r o u n d . T h r e a d s are g r o u n d by m e a n s of cutting contact between a r o t a t i n g g r i n d i n g wheel plus a relative axial transverse
between t h e two.
G e a r Grinding
G e a r g r i n d i n g is especially a d a p t e d to finishing gears that r e q u i r e considerable stock r e m o v a l a f t e r h a r d e n i n g , a n d to p r o d u c e g e a r s of great accuracy.
T h e r e a r e two g e n e r a l classes of gear g r i n d i n g machines.
F o r m e d W h e e l G r i n d i n g . T h i s class of gear g r i n d i n g cuts g e a r teeth with a
c o n t o u r f o r m e d g r i n d i n g wheel. T h r e e d i a m o n d s a r e used f o r dressing—one
f o r each side f o r m a n d o n e f o r t h e o u t s i d e d i a m e t e r of t h e wheel. Accurate
h e a d settings m u s t be m a i n t a i n e d t o obtain consistent tooth profile.
G e n e r a t i o n G r i n d i n g . T h i s class of g e a r g r i n d i n g is similar to that of bobb i n g — p a s s i n g a rack t o o t h t h r o u g h t h e space of a revolving gear. T h e r e are
two g e n e r a l types of g e n e r a t i n g g r i n d e r s : o n e with r e c i p r o c a t i n g movement
between t h e wheel a n d g e a r axially a n d tangentially, a n d t h e o t h e r with reciprocating m o v e m e n t only in t h e tangential plane.
GEAR HOBBING
GEAR CUTTING
Gear c u t t i n g is usually associated with bevel-gear m a n u f a c t u r e . Some bevel
gears a r e cut on milling machines but most a r e of t h e g e n e r a t e d type which are
produced o n bevel-gear g e n e r a t i n g machines.
As an e x a m p l e , the usual straight-bevel-gear g e n e r a t o r uses two tools simulating teeth of an imaginary c r o w n gear a n d having straight cutting edges which
are m o u n t e d in h o l d e r s that a r e , in l u r n , o n a cradle. T h e cradle, with the tools,
rolls d u r i n g g e n e r a t i o n in relation to t h e work spindle o n which the gear blank
is m o u n t e d (see Fig. 4-47). T h e tools reciprocate across t h e face of t h e gear
blank in a series of cuts as i h e tools a n d gear blank roll t o g e t h e r , producing ihe
required profile s h a p e of i h e tooth. T h e blank is w i t h d r a w n at the e n d of each
generating roll, a n d t h e cradle a n d spindle roll back to t h e starting position for
the next looth.
GEAR SHAPING
Gear s h a p i n g uses a g e a r - s h a p e d c u l l e r wiih relieved culling edges which
rotates a n d reciprocates; i h e gear blank rotates but d o e s not reciprocate (see
Fig. 4-48). T h e motion of t h e tool is back a n d f o r t h across i h e gear blank, taking
a cut wilh each f o r w a r d stroke. At i h e start of t h e o p e r a t i o n , the tool slots into
ihe gear blank t h r o u g h t h e full d e p t h of o n e tooth space. Both, work a n d tool
are indexed b e f o r e each pass until successive passes a r e m a d e so that cutter
and work m e s h as two m a t e d gears
:
G e a r h o b b i n g is a g e n e r a t i n g process consisting of a r o t a t i n g workpiece, a
rotating c u t t i n g tool (called a hob) with t e e t h a r r a n g e d in a helical t h r e a d as
shown in Fig. 4-46, a n d a m a c h i n e which maintains a limed relationship between
Fig. 4r46.
Gear hobbing.
Fig. 4-47. Gear cutting.
80
S E L E C T I N G FLUIDS FOR M A C H I N I N G AND G R I N D I N G PROCESSES
LAPPING
81
GEAR SHAVING
Gear s h a v i n g is o n e of t h e finishing o p e r a t i o n s devised to i m p r o v e the dimensional accuracy o f g e a r s m a d e by h o b b i n g o r s h a p i n g m e t h o d s . Both rotary
r C KL 4 " 4 9 ) ,and rack lype Shaving
hnisn b e f o r e they a r e h a r d e n e d .
Fig. 4-49.
are used to
*ive
such
g e a r s a fine, accurate
Gear shaving.
Rotary Shaving
In rotary shaving, t h e tool is g e a r - s h a p e d with teeth that a r e closely «ashed
to f o r m m a n y c u t t i n g e d g e s . T h e tool a n d g e a r mesh a n d rotate t o g e t h e r T h e
c u t t i n g e d g e s have a sliding action that shears ofr thin, t h r e a d l i k e chips because
t h e c u t t e r d r i v é s t h e g e a r being m a c h i n e d , causing their axes of rotation to
cross at a n a n g l e of 10 to 15 d e g .
Rack Shaving
Rack s h a v i n g is essentially t h e same as rotary shaving except that t h e tool is
a rack that r e c . p r o c a i e s in mesh with t h e workpiece. T h e s h a v i n g effect is obtained by a n g u l a r m o t i o n of t h e rack o r by using helical teeth to finish straight
teeth, or straight t e e t h to finish helical t o o t h e d gears.
C^mf^ny)'
H
Multip,C
circular
MW
operation. (Courtesy. The Cincinnati Milling Machine
ABRASIVE CUTOFF
T h i s process uses an abrasive wheel f o r t h e c o m p l e t e cutoff of a piece of
material f r o m t h e workpiece. Almost any type of material can be cut. the highstrength thermal-resistant materials being t h e most difficult. Abrasive cutting
is fast, accurate, a n d provides g o o d finish characteristics in most materials.
£
HONING
SAWING
Sawing, as a m a c h i n i n g o p e r a t i o n , uses power-driven e q u i p m e n t to cut material to a d e s , r e d size o r r o u g h s h a p e . T h r e e kinds of machines a r e in c o m m o n
use in inetalworking: t h e p o w e r hack saw. t h e circular saw, a n d t h e bandsaw
T h e first consists simply of a saw blade m o u n t e d in a r e c i p r o c a t i n g rack T h e
machine m o p e r a t i o n imitates h a n d sawing, i.e.. t h e blade cuts o n t h e f o r w a r d
stroke a n d lifts f o r each back s t r o k e so that t h e teeth d o not d r a g in t h e cut
C u t t i n g s p e e d s a r e g e n e r a l l y low. a n d f e e d s generally light.
T h e circular saw generally replaces t h e p o w e r hack saw f o r heavy work as
illustrated in t h e multiple saw milling o p e r a t i o n in Fig. 4-50.
Cutoff b a n d s a w i n g m a c h i n e s w e r e a d a p t e d directly f r o m wood-cuttin K b a n d
saws and a r e used f o r cutoff of p a r t s that can be h a n d l e d easily a n d held o n t h e
saw table. T h e y a r e not feasible f o r cutoff work o n long o r heavy barstock
H o n i n g is an abrasion process to b r i n g both e x t e r n a l a n d internal cylindrical
surfaces to a high-quality finish with high d i m e n s i o n a l a n d geometric accuracy
a f t e r m a c h i n i n g a n d finish g r i n d i n g . Abrasives in slick f o r m a r e spaced evenly
about t h e tool used f o r internal h o n i n g . T h e s e maintain a n o u t w a r d pressure
against t h e b o r e s u r f a c e to cause t h e grits t o cut. a n d to provide the feed action
as t h e d i a m e t e r increases. T h e m o t i o n of t h e h o n i n g tool is two-fold: it reciprocates entirely t h r o u g h t h e length of t h e b o r e , a n d rotates slowly at t h e same time.
H o n i n g stones a r e m a d e to specifications similar to those of g r i n d i n g wheels.
A l u m i n u m o x i d e , silicon carbide, o r d i a m o n d grits a r e b o u n d in stick f o r m with
a metallic, resinoid, o r vitreous b o n d . Various g r a d e s a n d grains a r e available.
LAPPING
L a p p i n g is a n o t h e r m e a n s of p r o d u c i n g a fine finish o n g r o u n d p a r t s o r Hat
surfaces. L a p p i n g processes usuallv r e m o v e n n m n r * r h m n n i ,r> «-»r
82
S E L E C T I N G F L U I D S F O R M A C H I N I N G A N D G R I N D I N G P R O C E S S E SGEARSHAPING7!)
E x t r e m e l y f i n e , l o o s e a b r a s i v e s (called H o u r ) a r e u s e d to r u b d o w n t h e s u r f a c e .
O n g r o u n d p a r t s , a t o o l o f r e l a t i v e l y s o f t m a t e r i a l s u c h as brass, c o p p e r , cast i r o n ,
o r lead is u s e d . F o r i n t e r n a l l a p p i n g , t h e tool is d e s i g n e d t o e x p a n d as t h e h o l e
e n l a r g e s o r , f o r e x t e r n a l l a p p i n g , to c o n t r a c t as t h e o u t s i d e d i a m e t e r d e c r e a s e s .
m » ?
REFERENCES
1.
•J.
3.
4.
5.
6.
7.
MRA Technical S u f i , Machining Data Handbook '(Cincinnati, Ohio: Meicut Research Associates,
Inc.. 1966). p. 462.
R. L Vaughn and H. B. Miller. " T h e Why of Metalworking Fluids,"/fSTAf/T Paper So. 6 / U ( l 9 6 5 ) ,
ADP Machinability Laboratory, Lockheed-California Company, Burbank, California, 1966.
C. A. Sluhan, "Cutting Fluids." ASTME Paper No. 399 (1962). Book I.
B. T . Chao a n d K. J . T r i g g e r , " T e m p e r a t u r e Distribution o n the Tool Chip and Tool Work Interface in Metal Cutting," ASME Paper No. 56-AS7.
M. G. Shaw, "Mechanical Activation —A Newly Developed Chemical Process," J. Appt. Mech.,
(March, 1948), 3 7 - 4 4 .
R. L. V a u g h n . Shop Famiiiariiation — Machining Section, Lockheed-California Company. Burbank,
California. 1955.
CHMERQL
ACCEPTABILITY
OF CtlTTIHG FLUIDS
C u l l i n g Huids h a v e c h e m i c a l a n d physical p r o p e r t i e s w h i c h i n f l u e n c e t h e i r
p e r f o r m a n c e u n d e r m a c h i n i n g c o n d i t i o n s , i.e., c u t t i n g a n d g r i n d i n g o p e r a t i o n s .
B e c a u s e t h e r e a r e so m a n y v a r i a b l e s i n v o l v e d in m a n u f a c t u r i n g o p e r a t i o n s —
metal u n i f o r m i t y ; u n i f o r m i t y o f c u t t i n g tools, g r i n d i n g w h e e l s , a n d m a c h i n e s ;
as well as o p e r a t o r ' s skill, j u d g m e n t , e x p e r i e n c e , etc.— a n y variations in t h e
c h e m i c a l a n d physical p r o p e r t i e s o f t h e c u t t i n g o r g r i n d i n g Huids u s e d c a n be
critical. T h e r e f o r e , reliability is a m o s t i m p o r t a n t c r i t e r i o n of a g o o d m e t a l w o r k ing fluid.
T o a s s u r e reliability, m a n y u s e r s as well as m a n u f a c t u r e r s of c u t t i n g a n d
g r i n d i n g fluids establish r e s e a r c h l a b o r a t o r y p r o c e d u r e s t o e v a l u a t e t h e s e fluids
in t e r m s o f : (1) u n i f o r m i t y o f t h e p r o d u c t , a n d (2) s a t i s f a c t o r y p e r f o r m a n c e
in service.
E v e n t h o u g h physical, c h e m i c a l , a n d m e c h a n i c a l tests a r e p e r f o r m e d o n a
fluid in t h e l a b o r a t o r y s e t t i n g , s u c h tests c a n n o t b e u s e d a s t h e o n l y o r a b s o l u t e
criteria f o r fluid quality o r p e r f o r m a n c e . T h e y s h o u l d b e v e r i f i e d by p u t t i n g a
p r o d u c t in a c l e a n m a c h i n e t o o l — u n d e r a c t u a l p r o d u c t i o n c o n d i t i o n s , o r in a
specially e q u i p p e d m a c h i n a b i l i t y l a b o r a t o r y — a n d r u n it o v e r a p e r i o d o f w e e k s
o r m o n t h s t o o b t a i n t h e p r o p e r e v a l u a t i o n . S u c h a "test r u n " c a n u n c o v e r p r o d uct q u a l i t i e s t h a t c a n n o t b e d e t e r m i n e d by r e s e a r c h l a b o r a t o r y e v a l u a t i o n techniques alone.
W h e n c u t t i n g o r g r i n d i n g is p e r f o r m e d , t h e physical f a c t o r s of u n i t p r e s s u r e ,
t e m p e r a t u r e , a n d t i m e a r e i n v o l v e d , t o g e t h e r with t h e c h e m i c a l f a c t o r s o f t h e
tool a n d w o r k p i e c e (or g r i n d i n g w h e e l a n d w o r k p i e c e ) . In t h e s e o p e r a t i o n s , t h e
fluid h e l p s t o c o n t r o l t h e b u i l t - u p e d g e o r r e d u c e d i f f u s i o n a t t h e t o o l / c h i p /
w o r k p i e c e i n t e r f a c e s . It is e v i d e n t t h a t t h e r e is n o s e r i e s o f r e s e a r c h l a b o r a t o r y
e x p e r i m e n t s t h a t will d u p l i c a t e t h e f o r c e s i n v o l v e d u n d e r actual p l a n t p r o d u c tion c o n d i t i o n s . T h i s m a k e s a m a c h i n a b i l i t y l a b o r a t o r y v e r y u s e f u l .
T o test a fluid's ability t o fulfill a p a r t i c u l a r set o f r e q u i r e m e n t s in a p a r t i c u l a r
p r o d u c t i o n p l a n t , a g i v e n m a c h i n e o r m a c h i n e s with a specific series o f c u t t i n g
tools ( o r g r i n d i n g w h e e l s ) s h o u l d b e set u p a n d r u n w i t h t h e fluid u n d e r c o n s i d e r a t i o n . I f a w a t e r miscible t y p e is u s e d , t h e m i n e r a l c o n t e n t o f t h e w a t e r s h o u l d
• be d e t e r m i n e d a n d t a k e n i n t o a c c o u n t . I n a d d i t i o n , t h e t y p e o f a t m o s p h e r e
GLOSSARY
oU which contains chemically acùve i n g r e d i e n t s to p r o -
A n
Active oil
m o t e b o u n d a r y lubrication.
A
Annealing
i n d u c e softness, o r r e f i n e s t r u c t u r e .
.
bv a solid lubricant (a m a t e n a l which h a s rel
Boundary
cation
Built-up
(BUE)
h e a t i n g a n d slow cooling cycle which may r e m o v e stress,
lubri-
edge
surfaces by chemical reaction.
A piece of w o r k material which h a s b e e n s t ^ n h a r d e n e d
a n d p r e s s u r e welded to t h e cutting e d g e of a tool.
A t u r n e d o v e r e d g e of metal resulting f r o m certain m a c h m -
Burr
S i f r ^ i c e T m p e r f e c t i o n s o n t h e work s u r f a c e usually caused
Chatter marks
by vibrations of t h e tool a n d / o r workpiece.
Chemical coolant
A c o m m o n e x t r e m e p r e s s u r e (EP) additive used to p r o m o t e
Chlorine
U
Coolant
Coupling
^
d
to coo, t h e work a n d tool a n d to p r e v e n t rust-
ing o r c o r r o s i o n ; c u t t i n g o r g r i n d i n g fluid.
agent
A m u t u a l solvent, a n emulsifier.
Creaming
Cutting fluid
Cutting rate
Dermatitis
Ductile
p e r u n i t of time.
A n u n n a t u r a l condition of t h e skin.
C a P a b , e of b
I S V e ' t
Emulsifiable oil
Emulsijier
A m2ial
e
i
n
g
^
^
^
a
„
emulsifier
o r
» " " J . fcrm a stab.e emulsion in water.
c o n t a i n i n g two types of mo.ecular g r o u p , o n e
155
CUTTING AND GRINDING
156
Of which Will o r i e n t in water a n d t h e o t h e r in oil.
Emulsion
EP additive
Ester
Ethane
Extreme pressure
additive
Extreme pressure
lubrication
Fatty acid
Fatty oils
Feed
Feed
Feed lines
Finish
Finishing
Germicide
Halogen
Hexane
Hydrodynamic
lubrication
Inverted emulsion
Machinability
Metallic soap
Micelle
It will,
thus, tie together two dissimilar liquids.
„
; n aa waterv
An oily mass •in suspension
in
watery liauid
iiqu or vice versa.
Extreme pressure additive.
A compound which may be formed by replacement of the
acid hydrogen of an acid by a hydrocarbon rad.cal.
A gaseous paraffinic hydrocarbon. (CHJCHJ), occumng
in natural gas.
A compound which reacts with the surface of the metal
(or too/Tforming thin films of metallic compounds (usually.
1 c h t o r L . sulfide, or phosphate) which have relauve.y low
shear-strength.
.
See "Boundary lubrication." In addiuon. withstands much
htgher pressures and temperatures than boundary lubr,
cated surface.
Any of the series of saturated or unsaturated acids (C„HJnO,)
f u c h
as stearic, oleic, and palmitic acids wh,ch occur ,n
natural fats and natural oils.
Organic oils; the most common are lard oil and sperm oil.
(Milling) The maximum thickness of material removed per
(Turning) The amount of horizontal movement of the tool
per revolution of the workpiece.
Spiral pattern produced on work in machining.
Surface quality or appearance.
The final cuts taken to obtain the accuracy and finish.
Any agent which destroys germs or micro-organisms.
The group of elements: chlorine, fluorine, bromine, and
Any^f five volatile liquid hydrocarbons. CeH u . of the paraffin series.
.
Lubrication where the viscosity of the lubricant keeps the
surfaces separated by a fluid film.
A dispersion of droplets of water in oil produced when a
s m a l l quantity of water is mixed with a relatively large quantity of oil.
..
The relative difficulty of a machining operation with regard
to tool life, surface finish, and power consumption.
The reaction product produced when a fatty acid reacts
with metal.
An aggregation of surface active molecules in a solut.on.
Mineral oil
Any oil of mineral origin such as petroleum.
Miscible
Capable of being mixed.
Any of a series of saturated cyclic hydrocarbons of
Naphthene
r
j
[ Olefin ,
S?
IE
Paraffin
£
ç
-
Peripheral speed
RPM
Soluble oil
Stearate
Stress corrosion
Sulfo-chlorviated
oil
Sulfur
.f."
Surface active
agent
Synthetic fluids
Tramp oil
?*.
Wettability
Wetting agent
j 5*>
Workpiece
Work hardening
GLOSSARY
Olefin
Paraffin
Peripheral speed
RPM
Soluble oil
157
g e n e r a l f o r m u l a C n H » ; a p p l i e d especially to those m e m b e r s
o c c u r r i n g in certain kinds of p e t r o l e u m .
Any o p e n - c h a i n h y d r o c a r b o n having o n e o r m o r e d o u b l e
bonds.
Any h y d r o c a r b o n of t h e m e t h a n e series, especially any of
t h e solid m e m b e r s boiling above 572°F.
T h e s p e e d of any point o n t h e s u r f a c e of t h e work (cutter
for rotary tool).
Revolutions p e r m i n u t e .
See "Emulsifiable oil."
Stearate
A salt o r ester o f stearic acid.
Stress corrosion
C o r r o s i o n facilitated by high residual s u r f a c e stress i m p o s e d
by m a c h i n i n g o r g r i n d i n g o p e r a t i o n s .
S ulfo-chlorinated
oil
Sulfur
Surface active
agent
Synthetic fluids
Tramp oil
Wettability
Wetting agent
Workpiece
Work
hardening
C u t t i n g oil c o n t a i n i n g s u l p h u r a n d chlorine.
A c o m m o n e x t r e m e p r e s s u r e (EP) additive used to p r o m o t e
b o u n d a r y lubrication.
Materials c a p a b l e of lowering s u r f a c e a n d interfacial tensions. See "Wettability."
P r o d u c t s which d o not contain any mineral oil a n d usually
f o r m a t r u e solution in water.
Leakage i n t o t h e c u t t i n g fluid system f r o m hydraulic o r
lubrication systems of m a c h i n e tools.
T h e relative ease with which a liquid s p r e a d s o v e r a surface.
A n additive which r e d u c e s s u r f a c e a n d interfacial tension
a n d , t h u s , facilitates s p r e a d i n g of a fluid, o v e r a s u r f a c e .
T h e part being machined.
A h a r d e n i n g process which may occur d u r i n g cold w o r k i n g
o r m a c h i n i n g ; strain h a r d e n i n g .
Memorandum
to the
Accident Offices
Association
* THE
INSURANCE
'TECHNICAL
'gUREAU
Title
HEALTH HAZARDS FROM
CUTTING FLUIDS
No.
Author
Date
AOA-M/OIO
J . G . Underwood
April,
1984.
SUMMARY AND CONCLUSIONS
C u t t i n g f l u i d s have been used by a l a r g e number of w o r k e r s i n a wide v a r i e t y of
i n d u s t r i e s f o r many y e a r s ; Most of t h e s e w o r k e r s a r e i n s m a l l e r f a c t o r i e s o r
workshops, so i t i s g r a t i f y i n g t h a t so few a d v e r s e h e a l t h e f f e c t s have been
recorded.
M a n u f a c t u r e r s have been q u i c k t o r e s p o n d t o t h e d e m o n s t r a t i o n of h e a l t h h a z a r d s
and have a c t e d t o e l i m i n a t e o r t o m i n i m i z e e x p o s u r e s t o t h e c a u s a l m a t e r i a l s .
Good d o c u m e n t a t i o n i s a v a i l a b l e from makers and t h e T r a d e A s s o c i a t i o n s .
Most of t h e h a z a r d s have c o n c e r n e d e m p l o y e r s 1 l i a b i l i t y i n s u r e r s , a l t h o u g h t h e r e
i s a l s o t h e p o s s i b i l i t y of l a n d and w a t e r p o l l u t i o n , e s p e c i a l l y by m i n e r a l o i l s .
T o d a y ' s problems a r i s e f r o m bad p r a c t i c e s a n d / o r l a c k of a w a r e n e s s ; u s u a l l y i n
t h e s m a l l e r and l e s s w e l l c o n t r o l l e d m a n u f a c t u r i n g u n i t s .
Economic f o r c e s which e n c o u r a g e t h e p r o t r a c t e d r e - u s e of c u t t i n g f l u i d s need t o
be v e r y c a r e f u l l y a s s e s s e d . P r i c e f a c t o r s i n t h e UK h a v e r e s u l t e d i n t h e
p r e d o m i n a n t u s e of o i l - b a s e d f l u i d s , w h i l e o v e r s e a s more s y n t h e t i c f l u i d s a r e i n
U6E.
Due t o t h e wide d i v e r s i t y of w o r k p l a c e s i n which c u t t i n g f l u i d s a r e u s e d , f u r t h e r
s t u d i e s of h e a l t h r i s k s w i l l need t o c o n s i d e r -the e x p e r i e n c e of w o r k e r s i n o t h e r
i n d u s t r i e s who a r e exposed t o t h e same m a t e r i a l s .
Nothing i s known a b o u t t h e c o n s e q u e n c e s of e x p o s u r e s t o m i x t u r e s o r t o t h e
s e c o n d a r y p r o d u c t s of c h e m i c a l and b i o l o g i c a l r e a c t i o n s w i t h i n t h e c u t t i n g f l u i d .
Newer m a t e r i a l s , i n c l u d i n g t h e u s e of o t h e r o i l s ( s u c h a s r a p e - s e e d o i l and
h i g h e r f a t t y a l c o h o l s ) w i l l r e q u i r e a c o n t i n u i n g s t u d y of w o r k e r s ' h e a l t h .
HISTORY OF CUTTING FLUIDS
S i n c e t h e end of t h e 16th c e n t u r y gun b a r r e l s were d r i l l e d u s i n g w a t e r a s a
c o o l a n t . Over 200 y e a r s ago t h e problems of c o r r o s i o n and l a c k of l u b r i c a t i o n
l e d t o t h e u s e of a l k a l i ( s o d a a s h ) and f a t t y a c i d s ( s o a p s ) a s a d d i t i v e s .
Subsequent d e v e l o p m e n t s i n c l u d e d u s e of t h e l u b r i c a n t s l a r d , l a t e r m i n e r a i o i l ,
t h e n a m i x t u r e of t h e two. S u l p h u r was added t o improve c u t t i n g p r o p e r t i e s - t h e
f i r s t heavy d u t y c u t t i n g f l u i d .
The Bureau is
Registered in England no. 1166023. Registered Offleo 52 Crowenor Gardens, London svnw qau.
devoted to trie study and communication of information and advice for the benefit of the insurance industry ana those requiring insurance.
The Bureau s liability for any Information or advice given shall be limited t o the amount of any charge made by the Bureau for such information or advice,
save as provided in the foregoing sentence (and except m respect of death or personal injury resulting from the Bureaus negligence) the Bureau accepts no
liability in
of any innrmatlon or any advice whatsoever, whether written or otherwise, given by the Bureau or any of Us officers or otherwise on its
behalf, whether negligent or not
respect
3
AOA-M/OIO
'
*
...
D u r i n g t h e 1914 war ' s o l u b l e o i l s ' came i n t o u s e . t h e s e c o n s i s t e d of m i n e r a l ' o r
f a t t y o i l e m u l s i o n s , p l u s soaps» s u l p h o n a t e s and p h e n o l i c s f o r s t a b i l i z a t i o n and
as corrosion i n h i b i t o r s .
a
I n t h e 1950s a l t e r n a t i v e a n t i - c o r r o s i o n a g e n t s t o soda a s h . b a s e d on a l k a l i
n i t r i t e s and o r g a n i c amines w e r e d e v e l o p e d and were i n g e n e r a l u s e f o r o v e r a
q u a r t e r of a c e n t u r y *
j j
x
w
INCIDENTS INVOLVING CUTTING FLUIDS
Many i n c i d e n t s have been r e c o r d e d i n which c u t t i n g f l u i d s have caused h e a l t h
p r o b l e m s ; amongst t h e more c a r e f u l i n v e s t i g a t i o n s a r e : Birmingham, 1950-1966, E x c e s s s k i n c a n c e r was found i n 65 t o o l s e t t e r s , l a t e n t
p e r i o d 30-40 y e a r s .
S h e f f i e l d , 1970s. 700 w o r k e r s exposed d a i l y , 30 c a s e s e a c h y e â r of i n d u s t r i a l
d e r m a t i t i s r e s u l t e d . A f t e r . u s e of a b i o c i d e t h i s f e l l t o 5 c a s e s each y e a r .
S h e f f i e l d , 1978. ,In a d d i t i o n t o s k i n p r o b l e m s , w o r k e r s i n a t o o l s t e e l f i r m
d e v e l o p e d l u n g p r o b l e m s . B a c t e r i a were found i n t h e g r i n d i n g f l u i d .
USA, 1980s. Two o u t b r e a k s of L e g i o n n a i r e s ' d i s e a s e o c c u r r e d amongst m a c h i n i s t s
(80 c a s e s ) . The c a u s a l o r g a n i s m was i s o l a t e d f r o m t h e c o o l a n t .
TYPES OF CUTTING FLUIDS
Two main t y p e s of c u t t i n g f l u i d s a r e in u s e : Neat o i l s ( s t r a i g h t o i l s ) , b a s e d on m i n e r a l o i l s .
Vatermix f l u i d s ( w a t e r e x t e n d i b l e ) , c o n c e n t r a t e s d i l u t e d w i t h w a t e r b e f o r e u s e ,
are subject to microbial contamination, Include:
. E m u l e i f i a b l e o i l s , >50% m i n e r a l o i l
• S e m i - s y n t h e t i c s , <50% m i n e r a l o i l
. S y n t h e t i c s ( c h e m i c a l , p u r e s y n t h e t i c ) , no m i n e r a l o i l .
Meat O i l s These t r a d i t i o n a l f l u i d s a r e s t i l l i n u s e , m a i n l y f o r h i g h q u a l i t y
f i n i s h e s . M i n e r a l o i l i s a c i d t r e a t e d and s o l v e n t e x t r a c t e d t o remove t h e
a r o m a t i c s (which were r e s p o n s i b l e f o r s k i n c a n c e r ) . . Common a d d i t i v e s i n c l u d e : F a t t y a c i d s and e s t e r s
- improve c u t t i n g p e r f o r m a n c e
Extreme p r e s s u r e a d d i t i v e s - c h l o r i n a t e d p a r a f f i n s ( l u b r i c a n t )
- sulphonated o i l s a n d . f a t s (performance
increasers)
- f r e e sulphur ( l e a s t e f f e c t i v e ) .
L e s s common a d d i t i v e s
- o r g a n o - p h o s p h a t e s e . g . t r i - a r y l and t r i - a l k y l
phosphates, zinc d i - a l k y l dithiophosphates
(Increase cutting performance).
Watermix f l u i d s Used i n 80% of m a c h i n i n g o p e r a t i o n s .
. E m u l s i f i a b l e o i l s ( " s u d s " ) c o n t a i n m i n e r a l o i l ( a s i n n e a t o i l s ) and a r e
used a s milky e m u l s i o n s by d i l u t i o n ( 1 : 5 t o 1:50) w i t h w a t e r . The p r i n c i p a l
additives include
F a t t y s o a p s , sodium p e t r o l e u m s u l p h o n a t e s - e m u l s i f i e r s
Extreme p r e s s u r e a d d i t i v e s - i n c l u d i n g f a t s and s u l p h u r - o r c h l o r i n e - c o n t a i n i n g
fats
. S e m i - s y n t h e t i c s , t h e most r e c e n t d e v e l o p m e n t , a r e used a s c l e a r , s t a b l e
e m u l s i o n s c o n t a i n i n g low l e v e l s of o i l w i t h a d d i t i v e s a6 i n t h e o t h e r
"Vwatermix f l u i d s , and a r e d i l u t e d 1:10 t o 1:100 i n w a t e r .
. S y n t h e t i c s a r e w a t e r - b a s e d s o l u t i o n s ( 1 : 3 0 t o 1:200) c o n t a i n i n g no
YHE
3
t m w S S S1
iSÏÏSSf
'BUREAU
w
Memorandum
Accident Offices
Association
continued
AOA-M/OiO
l u b r i c a n t . A d d i t i v e s , o t h e r than t h o s e mentioned a£ove, i n c l u d e : T r i e t h a n o l a o i n a - s u r f a c e a c t i v e agent
Sodium n i t r ^ è - ? - c o r r o s i o n i n h i b i t o r
Benzotriazole
- o r s i m i l a r a d d i t i v e t o p e r m i t ' y e l l o w m e t a l work 1 i . e . on
c o p p e r and i t s a l l o y s .
A more comprehensive l i s t of a d d i t i v e s i s g i v e n i n T a b l e 1.
PROPERTIES OF CUTTING FLUIDS
The main f u n c t i o n s , of a c u t t i n g f l u i d a r e t o c o o l and l u b r i c a t e t h e t o o l and t h e
workplece.
. C o o l i n g . High s p e c i f i c h e a t and t h e r m a l c o n d u c t i v i t y e n s u r e minimum
e x p a n s i o n d u r i n g m a c h i n i n g , hence i n c r e a s e d d i m e n s i o n a l a c c u r a c y .
• L u b r i c a t i o n . R e d u c t i o n of f r i c t i o n between t h e t o o l and t h e w o r k p l e c e and
e f f i c i e n t swarf removal r e q u i r e s good o l l i n e s s , good w e t t i n g and optimum
v i s c o s i t y . These p e r m i t o p t i m i s a t i o n of c u t t i n g s p e e d , t o o l l i f e ,
p r o d u c t i v i t y , c o s t , power consumption and s u r f a c e f i n i s h .
SELECTION OF CUTTING FLUIDS
The s e l e c t i o n of t h e a p p r o p r i a t e c u t t i n g f l u i d f o r a g i v e n o p e r a t i o n i s v e r y .
complex, i n v o l v i n g c o n s i d e r a t i o n s of p r a c t i c a b i l i t y , s a f e t y and e c o n o m i c s .
Tool m a t e r i a l s were f o r m e r l y c a r b o n s t e e l s , now r e p l a c e d by h i g h speed s t e e l s
w i t h which any t y p e of c u t t i n g f l u i d may be u s e d . More r e c e n t l y I n t r o d u c e d
m a t e r i a l s i n c l u d e cemented o r s i n t e r e d c a r b i d e s , c e r a m i c s and diamonds which a r e
used i n h i g h - s p e e d m a c h i n i n g n e e d i n g v e r y e f f i c i e n t c o o l i n g by a s y n t h e t i c o r
semi-synthetic water-based f l u i d .
The s e v e r i t y of t h e m a c h i n i n g o p e r a t i o n depends on t h e f o r c e u s e d . As t h e
l o a d i n g i n c r e a s e s . t h e r e l ç . a g r e a t e r r e q u i r e m e n t f o r l u b r i c a t i o n and c o o l i n g .
Thus b o t h t h e w o r k p l e c e m a t e r i a l and t h e m a c h i n i n g o p e r a t i o n d e t e r m i n e t h e
s e v e r i t y and s e l e c t i o n of t h e c u t t i n g f l u i d . T h i s i s i n d i c a t e d i n T a b l e 2,
The u s e s of t h e v a r i o u s t y p e s of c u t t i n g f l u i d s a r e shown i n T a b l e 3 , t h e
s e l e c t i o n of t h e a p p r o p r i a t e f l u i d i s o u t l i n e d i n T a b l e 4 , w h i l e T a b l e 5 g i v e s
t h e d i s t r i b u t i o n of u s e of c u t t i n g f l u i d s by US i n d u s t r y .
HEALTH HAZARDS OF CUTTING FLUIDS
The p r i n c i p a l h e a l t h h a z a r d s d u e t o c u t t i n g f l u i d s a r e p e r c e i v e d t o be s k i n
c a n c e r f r o m m i n e r a l o i l s , f o r m a t i o n of n i t r o s a m i n e s f r o m amines and n i t r i t e s and
i n f e c t i o n s by m i c r o b e s .
. E x p o s u r e s . I n t h e USA i t i s e s t i m a t e d t h a t j u s t u n d e r 1 m i l l i o n w o r k e r s a r e
exposed t o c u t t i n g f l u i d s . About 6 0 , 0 0 0 US p l a n t s u s e t h e s e f l u i d s and most a r e
s m a l l , h a v i n g 10-100 e m p l o y e e s . ,
. Skin D i s e a s e s . D e r m a t i t i s r e s u l t s by two mechanisms. Removal of t h e
n a t u r a l f a t s i n s k i n by o i l s (and s o l v e n t s , d e t e r g e n t s e t c ) r e s u l t s i n a 1%
i n c i d e n c e of a c h r o n i c eczematous r a s h .
I f t h e p o r e s of t h e s k i n a r e b l o c k e d by
o i l s , f o l l i c u l i t i s ( a c n e ) may r e s u l t .
S e n s i t i z a t i o n t o components of t h e c u t t i n g f l u i d s may a l s o r e s u l t .
Such a l l e r g i c
r e s p o n s e s o c c u r t o many of t h e a d d i t i v e s e . g . t h e a n t l - o x l d a n t s and
a n t i - c o r r o s i v e s , p l u s some b l o c l d e s .
( r e g i s t e r e d in England NO. 1166025. R e g i s t e r e d o f f i c e S3 Crosvenor Garden», London SW1W 0AU.
AOA-M/OIO
M i c r o b i a l c o n t a m i n a t i o n docs n o t a p p e a r t o c a u s e s k i n r e a c t i o n s .
^
^
Skin c a n c e r i s c o n s i d e r e d b e l o w ,
. Lung D i s e a s e s . I t h a s l o n g been known t h a t t h o s e c l o s e s t t o machines
d e v e l o p t h e g r e a t e s t i n c i d e n c e of u p p e r r e s p i r a t o r y t r a c t d i s e a s e s . O i l m i s t may
be i n v o l v e d i n t h e development of a c u t e and c h r o n i c f i b r o s i s of t h e l u n g a n d ,
more r a r e l y of l i p o i d pneumonia. Any smoke g e n e r a t e d from improper working
p r a c t i c e s would add t o t h i s h a z a r d . I t i s a l s o p o s s i b l e t h a t h a r d m e t a l l u n g
f i b r o s i s could occur in m a c h i n i s t s .
. Cancer. Early epidemiological s t u d i e s revealed
c a u s e s s k i n c a n c e r , i n c l u d i n g c a n c e r of t h e s c r o t u m .
p o l y c y c l i c a r o m a t i c h y d r o c a r b o n s - t h e s e a r e removed
t h a t a r e u s e d i n modern i n d u s t r y , so t h e r e s h o u l d be
s o u r c e . I t s h o u l d be n o t e d t h a t t h e w a t e r m i x f l u i d s
and a r e d i l u t e d f u r t h e r b e f o r e u s e .
t h a t exposure to mineral o i l
The a c t i v e a g e n t s a r e t h e
in the solvent refined o i l s
no f u r t h e r problem from t h i s
c o n t a i n low l e v e l s of o i l s
A s t u d y of 65 t o o l s e t t e r s i n Birmingham f r o m 1950 t o 1966 showed t h a t t h e
p e r i o d f o r t h i s c a n c e r was 30-40 y e a r s .
latent
. N i t r o s a m i n e s . S i n c e t h e 1950s i t h a s been known t h a t most n i t r o s a m i n e s
c a u s e c a n c e r i n e x p e r i m e n t a l a n i m a l s ( s e e ITB memo AOA-M/008, March 1984).
C u t t i n g f l u i d s u s e d t o c o n t a i n n i t r i t e and a m i n e s , such a s t r i e t h a n o l a m i n e , b u t
now t h e y a r e n o t i n c o r p o r a t e d t o g e t h e r i n t h e same f o r m u l a t i o n .
C u t t i n g f l u i d s t h a t c o n t a i n e d t r i e t h a n o l a m i n e and sodium n i t r i t e a l s o c o n t a i n e d
up t o 0.4Z of t h e a n i m a l c a r c i n o g e n n i t r o s o d i e t h a n o l a m i n e , b u t a s t u d y of 780,000
w o r k e r s i n t h e USA who were exposed t o such s y n t h e t i c f l u i d s r e v e a l e d no e x c e s s
m o r t a l i t y ( t h e r e was a s l i g h t i n c r e a s e i n r e s p i r a t o r y and d i g e s t i v e c a n c e r - of
doubtful s t a t i s t i c a l significance).
To d a t e t h e r e i s no c o n n e c t i o n between t h e u s e of w a t e r - b a s e d s y n t h e t i c
f l u i d s and c a n c e r .
cutting
. Microbial Contamination.
Known c o n s e q u e n c e s of b a c t e r i a l c o n t a m i n a t i o n of
c u t t i n g f l u i d s a r e eye and wound i n f e c t i o n s .
I n t h e o r y , h e a l t h h a z a r d s due t o m i c r o b e s c o u l d a r i s e f r o m : i.
I n h a l a t i o n of o r g a n i s m s i n t h e c u t t i n g f l u i d a e r o s o l .
Secondary i n f e c t i o n c o u l d r e s u l t f r o m o p p o r t u n i s t p a t h o g e n s ,
i i . M i c r o b e s i n t h e a e r o s o l c o u l d c a u s e r e s p i r a t o r y m a l f u n c t i o n by mechanisms
o t h e r t h a n i n f e c t i o n and g r o w t h ,
iii.
Microbes c o u l d change t h e c o m p o s i t i o n of t h e c u t t i n g f l u i d t o g i v e
deleterious effects.
At p r e s e n t t h e r e i s a l i t t l e e v i d e n c e f o r i , b u t none f o r i i and
Examples of m i c r o b i a l c o n t a m i n a t i o n
iii.
include:-
Pseudomonas a e r o g i n o s a - an a e r o b i c s p o i l a g e b a c t e r i u m and a c c e p t e d o p p o r t u n i s t
p a t h o g e n . T h i s o r g a n i s m r a p i d l y d i e s i n c u t t i n g f l u i d and does n o t c o l o n i s e t h e
r e s p i r a t o r y t r a c t a f t e r i n h a l a t i o n of t h e a e r o s o l .
I t can c a u s e eczema and
5
TUB
Memorandum
tôt!»
AccktartOfflces
Association
continued
9
I ne
TECHNICAL
"BUREAU
•
""
AOA-M/OIO
Q
No.
p o s s i b l y c o r n e a l damage t o t h e e y e .
1 i n 4 samples of c u t t i n g f l u i d s .
A Cardiff survey revealed i t s presence i n
A s p e r g i l l u s f u m i g a t u s - a mould, o f t e n i s o l a t e d from c u t t i n g f l u i d s , b u t of no
known t o x i c o l o g i c a l s i g n i f i c a n c e (See ITB memo t o t h e AOA - M/008 A p r i l . 1984).
Other p a t h o g e n i c b a c t e r i a - e . g . S t a p h y l o c o c c u s a u r e u s ( c a u s e of s e p t i c
i n f e c t i o n s ) and S a l m o n e l l a s p p . ( f o o d p o i s o n i n g ) , h a v e been i s o l a t e d from c u t t i n g
f l u i d s . They d i e i n t h e f l u i d and do n o t add t o t h e normal i n f e c t i o n l e v e l . Indeed
t h e i r s o u r c e i n t h e f l u i d i s t h e worker I
L e g i o n n a i r e s * D i s e a s e ( - See ITB - Memo t o t h e AOA - M148/80/11, N o v . , 1980).
Two o u t b r e a k s have been documented i n workshop w o r k e r s , b u t i t i s n o t c l e a r
whether t h e i n f e c t i o n was caused by t h e o r g a n i s m s i n t h e c u t t i n g f l u i d . Only
s u s c e p t i b l e h o s t s w i l l d e v e l o p t h e d i s e a s e - a g e i n g men w i t h r e s p i r a t o r y
problems•
Other Organisms - moulds and y e a s t s . The a l k a l i n e c u t t i n g f l u i d i s s e l e c t i v e f o r
b a c t e r i a , b u t t h e combined e f f e c t s of u s e and b a c t e r i a l i n f e c t i o n c a u s e t h e f l u i d
t o become more a c i d i c . Moulds and y e a s t s can t h e n grow. The main e f f e c t s of
t h i s growth a r e on p e r f o r m a n c e of t h e f l u i d and c o r r o s i o n .
I t seems t h a t t h e w o r k e r s a t g r e a t e s t r i s k of i n f e c t i o n from c o n t a m i n a t e d c u t t i n g
f l u i d s a r e t h o s e on immunosuppressive d r u g s , e . g . t h e a n t i n e o p l a s t i c a g e n t s used
t o t r e a t m a l i g n a n t d i s e a s e and t h e c o r t i c o s t e r o i d s u s e d a s a n t i - i n f l a m m a t o r i e s ,
a n t i - a l l e r g i c s and a g a i n s t r h e u m a t i c a r t h r i t i s .
PERFORMANCE MONITORING OF CUTTING FLUIDS
In view of t h e p o t e n t i a l h a z a r d s , m a i n t e n a n c e of t h e c l e a n l i n e s s of t h e c u t t i n g
f l u i d (and t h e p l a n t ) I s e s s e n t i a l .
F i l t r a t i o n ( e i t h e r mechanical or magnetic),
skimming and c e n t r i f u g a t i o n a r e a l l u s e d . A b a t t e r y of t e s t s f o r u s e i n q u a l i t y
c o n t r o l i s g i v e n i n t h e I n s t i t u t e of P e t r o l e u m ' s "Code of P r a c t i c e f o r
Metalworking F l u i d s " (Heyden and Son L t d . , J u l y 1 9 7 8 ) , t h i s i n c l u d e s measurement
of c o n c e n t r a t i o n of o i l m i s t , c o n t a m i n a t i o n , v i s c o s i t y and pH. R e c o n d i t i o n i n g
and r e c l a m a t i o n of c u t t i n g f l u i d s a r e c o v e r e d i n t h e same document.
Simple d i p - s l i d e t e s t a f o r t h e s e m i q u a n t i t a t i v e d e t e r m i n a t i o n of a v a r i e t y of
m i c r o b i a l contaminants a r e a l s o a v a i l a b l e , see f o r example:
E.C. H i l l . M i c r o b i a l I n f e c t i o n of C u t t i n g O i l s , T r i b o l o g y I n t e r n a t i o n a l ,
1977, 2 0 ,
53-4.
CONTROL OF CUTTING FLUID HAZARDSDISPOSAL
C o n t a m i n a t i o n of t h e c u t t i n g f l u i d l e a d s t o r e d u c e d t o o l and f l u i d l i f e , i n f e r i o r
f i n i s h and h e a l t h h a z a r d s .
. O i l m i s t . C o n t r o l l e d by l o c a l e x h a u s t v e n t i l a t i o n , r e s p i r a t o r s s h o u l d o n l y
be used d u r i n g i n s t a l l a t i o n and m a i n t e n a n c e of t h e v e n t i l a t i o n and i n
e m e r g e n c i e s . Low m i s t c u t t i n g f l u i d s a r e used i n p a r t i c u l a r l y h a z a r d o u s
operations.
P r o t e c t i v e c l o t h i n g s h o u l d be i m p e r v i o u s t o t h e f l u i d .
. N i t r o s a m i n e s . S u b s t i t u t i o n e l i m i n a t e s t h i s h a z a r d , n i t r i t e s and amines a r e
not used i n t h e same f l u i d .
. M i c r o b i a l I n f e c t i o n . The most e f f e c t i v e method of m i c r o b i o l o g i c a l c o n t r o l
i s good h o u s e k e e p i n g . Minimal c o n t a m i n a t i o n of e a c h f r e s h b a t c h of c u t t i n g f l u i d
and d i l u t i o n by t a p w a t e r ( n o t c o n t a m i n a t e d w a t e r ) a r e e s s e n t i a l .
Organic
c o n t a m i n a t i o n , i n u s e (by f o o d w a s t e s , r a g s , f l o o r s w e e p i n g s and even u r i n e )
Registered
in cnyt«nu
Englandnw.
MO. »1 1 6 6 0 2 3 . Registered
n e g i n v r v a in
— Office 5 2 crowenor Gardens. London S W I W
OAU.
C
AOA-M/OIO
s h o u l d be a v o i d e d . C o n t r o l of i n f e c t i o n by b i o c i d e a d d i t i o n i s t h e second l i n e
of d e f e n c e . S t e r i l i s a t i o n of t h e f l u i d by u s e of y-raye,
uv l i g h t o r ozone can
form u n d e s i r a b l e c h e m i c a l s . P a s t e u r i s a t i o n i s o f t e n t h e most a c c e p t a b l e m e t h o d ,
e s p e c i a l l y where f i l t r a t i o n f a l l s .
. D i s p o s a l . I n a l l b u t t h e l a r g e s t o r g a n i s a t i o n s , d i s p o s a l by an o u t s i d e
c o n t r a c t o r i s p r o b a b l y t h e b e s t . D r a i n i n g a n d / o r f i l t r a t i o n t o remove t h e swarf
and s p l i t t i n g of e m u l s i o n s w i l l y i e l d an o i l t h a t ma^ be u s e a b l e f o r f u e l .
S p e c i a l i s t a d v i c e s h o u l d be o b t a i n e d b e f o r e such u s e .
S i n c e o n l y 20 ppm of o i l i s a l l o w e d i n w a t e r e f f l u e n t f u r t h e r p u r i f i c a t i o n i s
n e c e s s a r y . U l t r a f i l t r a t i o n , c e n t r i f u g a t i o n , r e v e r s e o s m o s i s a r e a l l methods t h a t
a r e i n u s e p r i o r t o d i s p o s a l a s w e l l a s i n e x t e n d i n g t h e u s e f u l l i f e of t h e
fluid.
LEGISLATION, CODES OF PRACTICE, ETC
. UK L e g i s l a t i o n . T h e r e i s no s p e c i f i c l e g i s l a t i o n a p p l y i n g t o c u t t i n g
f l u i d s . Relevant, general l e g i s l a t i o n Includes
The H e a l t h and S a f e t y a t Work e t c . A c t , 1974 and The C o n t r o l of P o l l u t i o n A c t ,
1974 and R e g u l a t i o n s t h e r e u n d e r .
. H e a l t h and S a f e t y E x e c u t i v e P u b l i c a t i o n s . These i n c l u d e : D e r m a t i t i s ( C a u t i o n a r y N o t i c e ) , SHW 367.
E f f e c t s of m i n e r a l o i l on t h e s k i n ( C a u t i o n a r y N o t i c e ) , SHW 3 9 7 .
Skin c a n c e r by p i t c h and t a r ( c a u t i o n a r y p o c k e t - c a r d f o r w o r k e r s ) , MS (B)4.
Skin c a n c e r c a u s e d by o i l ( c a u t i o n a r y p o c k e t - c a r d f o r w o r k e r s ) , MS(B)5.
Occupational ( I n d u s t r i a l ) Dermatitis (cautionary pocket-card f o r workers),
MS(B)6.
. Other u s e f u l p u b l i c a t i o n s : M i n i s t r y , of L a b o u r . " I n d u s t r i a l D e r m a t i t i s P r e c a u t i o n a r y Measures , S a f e t y ,
H e a l t h and W e l f a r e B o o k l e t , New S e r i e s , No. 18, (HMSO).
^
M e d i c a l R e s e a r c h C o u n c i l , "The C a r c i n o g e n i c A c t i o n of M i n e r a l O i l s ,
SRS306» 1968, (HMSO).
. DHSS P r e s c r i b e d D i s e a s e s :
C o n d i t i o n s due t o c h e m i c a l a g e n t s , C21 ( p r e v i o u s l y 23b and 2 3 c ) , w a r t s and
s c a l i n e s s , s k i n c a n c e r c a u s e d by h a n d l i n g , i n t e r a l i a , m i n e r a l o i l .
. KIIRA (The C e n t r e f o r Machine Tool Technology)
H u l l e y Road, M a c c l e s f i e l d . C h e s h i r e SK10 2NE, (0625) 25421, h a s an e x t e n s i v e
publications l i s t including:
" H e a l t h and S a f e t y i n t h e Machine Shop", 1978 ( £ 2 4 ) .
. I n s t i t u t e of P e t r o l e u m :
"Code of P r a c t i c e f o r M e t a l w o r k i n g F l u i d s " , p u b l i s h e d f o r t h e I . of P . by Heyden,
J u l y , 1978. T h i s code c o v e r s :
P l a n t and Equipment, S t o r a g e . Mixing and D i s p e n s i n g , U s e , M i c r o b i a l C o n t a m i n a t i o n
and C o n t r o l , H e a l t h H a z a r d s and P r e c a u t i o n s . R e c o n d i t i o n i n g , R e c l a m a t i o n and
Disposal.
. S h e f f i e l d Area T r a d e Union S a f e t y Committee:
B a c t e r i a i n O i l s and C o o l a n t s : a Code of P r a c t i c e - See P r i c e , Le Serve and
P a r k e r , " B i o l o g i c a l H a z a r d s - t h e Hidden T h r e a t " , N e l s o n , 1981. T h i s code c o v e r s :
V e n t i l a t i o n , M o n i t o r i n g , H a n d l i n g , C o n t r o l , S t a n d a r d s and Long-Term Aims.
. USA L e g i s l a t i o n . On 23 J a n u a r y , 1984 t h e E n v i r o n m e n t a l P r o t e c t i o n Agency
I s s u e d an I m m e d i a t e l y e f f e c t i v e p r o p o s e d r u l e ( u n d e r TSCA S e c t i o n 6 ( a ) ) b a n n i n g
t h e a d d i t i o n of n i t r i t e t o t r i e t h a n o l a m i n e c o n t a i n i n g m a t e r i a l s t h a t a r e or could
be used a s m e t a l w o r k i n g f l u i d s ( F e d e r a l R e g i s t e r , 1984, 4 9 , 2 7 6 2 ) . The EPA
«ig
^..rfkiM
NWMMS
TECHNICAL
'BUREAU
7
Memorandum
the
Accident Offices
Association
continued
to
N a
A0A-M/010
c o n t i n u e s i n v e s t i g a t i n g t h e g e n e r a l p r o b l e m of n i t r o s a m i n e f o r m a t i o n i n
m e t a l v o r k i n g f l u i d s and r e s e a r c h t o f i n d s u b s t i t u t e s f o r n i t r i t e s .
UK MANUFACTURERS OF CUTTING FLUIDS
C u t t i n g f l u i d s a r e produced by many of t h e o i l companies a s . w e l l a s a r a n g e of
s p e c i a l i t y chemical manufacturers
. O i l Companies i n c l u d e :
BP, C e n t u r y , C h e v r o n , M o b i l , S h e l l , Texaco
. S p e c i a l i s t Chemical M a n u f a c t u r e r s i n c l u d e s
Arrow, Boeing ( O r e l u b e ) , E . F . Houghton, Monsanto, N o r t o n , P a c i f i c C h e m i c a l s ,
P e n n w a l t , Q u a k e r , R o c o i , Smyth M o r r i s , Edgar Vaughan.
FURTHER INFORMATION
Two e x c e l l e n t r e v i e w s a r e a v a i l a b l e f r o m The Machine T o o l I n d u s t r y R e s e a r c h
^ c î a t î ^ m S r H u l l e y Road, M a c c l e s f i e l d , C h e s h i r e SK10 2NE, (0625) 25421 :
S y n t h e t i c C u t t i n g F l u i d s . 30 A p r i l , 1975 (£20 t o non-members)
H e a l t h and S a f e t y i n t h e Machine Shop. 23 November, 1978 (£24 t o non-members).
The l a t e s t T o x i c i t y Review (No. 8) f r o m t h e HSE i n c l u d e s ( P a r t I I I ) an e x c e l l e n t
d i s c u s s i o n of t h e p r o p e r t i e s of N - n i t r o s o d i e t h a n o l a m i n e , t h e a d v e n t i t i o u s
r e a c t i o n p r o d u c t i n c e r t a i n c u t t i n g f l u i d s t h a t c o n t a i n n i t r i t e and
triethanolamine.
A84 129/JGU/SW
2.5.84
Registered In England MO. 1 1 6 6 0 2 5 . Registered Office S2 Growenor Gardent. London swiw
nte Bureau « devoted to the
commun^ariono j^^orm^rjw^ntf J^^^J^j^^jStiMrt
The Bureaus uaomtv for anv I N F O R M A T / O N E V A D ^ E
G ^ N
J
J
M
RORNEJM^NR
^
«
T
F
OAU.
araSf^
S
^
SU/VZUS
negtioenw the BureauKceon no
AOA-M/OIO
table
1
ADDITIVES USED IN WAIERMIX CUTTING FLUIDS
Function
Additive
Notes
Emulsifiers
fatty oils
f a t t y acid soaps
petroleum s u l p h o n a t e s
non*ionics
e . g . lard o i l s
p o t a s h s o a p s , pH 9*10
pH 7 - 8
Detergents
metal sulphonates
metal phenates
Corrosion
inhibitors
sodium n i t r i t e
. alkanolamines
borates
dichromates
lead naphthenate
e.g. cetyl
e.g.
chlorophenols
o-phenylphenol
complex t r i a z i n e s
mercurials
Biocides*
V i s c o s i t y Index improvers
tricresyl
Extreme p r e s s u r e
organo-chlorine
organo-sulphur
sulphur
organo'phosphorus
organo"molybdenum
Yellow m e t a l
additives
inhibitors
stabilizers
n o t now u s e d t o g e t h e r
i n a formulation
n o t i n u s e now
«t ii
H M
higher alcohols
glycols
cresols
xylenols
Coupling a g e n t s
Hardwater
> C
' (
alcohol
2,6-di-t-butoxy-j>-cresol
l i b e r a t e formaldehyde
not In u s e now
phosphate
• benzotriazole
expoxide copolymers.
Antifoam
polysiloxanes
Dye8 and s c e n t s
various
j ( '
' *
a l s o m i x t u r e s of t h e s e
and o r g a n o - c h l o r i n e * s u l p h u r
and molybdenum di.sulphide
copper d e a c t i v a t o r
( e t h y l e n e and p r o p y l e n e )
may be added
* A review of commercial b i o c i d e s i n t h e USA i a : H.W. Rossmoore, J . Occup. Med., 1981 2 3 ( 4 ) , 2 4 7 - 2 5 4 .
jug
Memorandum
QMREAU
continued
N a
AOA-M/OiO
CyCy
Table 2
SEVERITY OF MACHINING OPERATIONS
Operation
Material
>*
Manganese a l l o y s
Magnesium a l l o y s
Zinc a l l o y s
Bronze
Brass
Aluminium a l l o y s
Mild S t e e l
Low c a r b o n s t e e l
Copper
H i g h - t e n s i l e bronze
Cast i r o n
Wrought i r o n
High c a r b o n s t e e l
Monel m e t a l ( n i c k r l , c o p p e r e t c )
Tool s t e e l
Stainless steel
I n c o n e l (Chromium, i r o n , n i c k e l )
Nimonic (Chromium, n i c k e l , i r o n e t c )
Titanium
V f
Ji
M
« 1
u
>
H
M
M
w
z
M
w
<
Grinding
Sawing
Simple t u r n i n g
Drilling
Planing, shaping
Milling
Deep h o l e d r i l l i n g
Reaming
Tapping
Gear c u t t i n g and s h a p i n g
Broaching
Piercing
Pressing
Drawing
w
*
u «
z
M
•
Taken f r o m : L.H. Haygreen, S e l e c t i o n of C u t t i n g F l u i d s ,
T r i b o l o g y I n t e r n a t i o n a l , 1977, 1 0 ( 1 ) , 1 3 - 1 4
and
Kempe 1 s E n g i n e e r s Y e a r - b o o k ,
8 8 t h E d i t i o n , Morgan Grampian, 1983, p . B 5 / 1 3 .
Registered in engiand wo. 1166025. Registered Office 32 Growenor Garden». London SW1W OAU.
red to we srudy and
The Bureau is devored
The Bureau s ..^JtYtormylnfonr^
iiaom
tManwunt&7r^
or aSîce
4
AOA-M/OIO
Table 3
THE USES OF CUTTING FLUIDS
Group 1. (Not water extendible)
EP additives
Vehicle
Mineral oil
Mineral oil
Mineral oil
Mineral oil
Mineral oil
None added
Fats
Fats and chlorinated
chemicals '
Fats and sulphurised
chemicals
Fats, plus both sulphurised
and chlorinated
chemicals
Chlorinated Solvents
»
Typical applications & observations
Light operations with simple piecing and blanking on mild
steel.
Low severity press operations.
Moderate to severe operations. Should be removed after
use. Solvent clean.
Heavy gauge blanking and piecing. May stain non-ferrous
metals. May attack carbide tooling.
Very severe operations. Deep drawings stainless steel.
For severe and heavy drawing. Usually of high viscosity
which can be reduced by addition of mineral oil for
automatic high speed press operations. May be difficult
to clean but should be removed after operation since
staining can result.
Group 2. (Water extendible)
Mineral oil plus
emulsifiers
Mineral oil plus
emulsifiers
Mineral oil plus
emulsifiers
None
Mineral oil plus
emulsifiers
Mineral oil plus
emulsifier
Fats, sulphurised chemicals
Fats
Chlorinated chemicals, fats
Fats, sulphurised and
chlorinate chemicals
Liquid soaps
Paste
Synthetics
Taken f r o m :
Soaps, fats, waxes, solid
lubricant
Usually poor EP activity
Light gauge forming. Especially for non-ferrous. Easily
applied by flood or spray.
Low severity piecing and forming.
High speed operations where good cooling is needed.
Cleaning can be done by aqueous or solvent. Must be
reapplied on multi-stage operations.
Moderate to severe draws. May stain non-ferrous
materials. Not suitable for carbide tooling.
Press operations of maximum severity with medium to
heavy gauge sheet. Can cause staining with non-ferrous
materials.
Light forming only with carbon steels. Can burn off
cleanly during annealing and therefore need not be
removed. However, can stain copper containing metals
and may give deposits on zinc.
Heavy draws particularly where surface finish is important. Cleaning may prove difficult.
Low severity operations. Can be easy to remove and can
burn off during annealing. Useful for special opera
tions. eg motor laminations, food containers.
Kempe's E n g i n e e r s Y e a r - b o o k ,
8 8 t h E d i t i o n , Morgan Grampian, 1983 p
B5/15.
e
THE
Memorandum
U
GSRSffi
TECHNICAL
'BUREAU
Accktert Offices
Association
...
No.
AOA-M/OIO
Q^
^
Table 4
GUIDE TO THE SELECTION OF CUTTING FLUIDS FOR GENERAL WORKSHOP APPLICATIONS
Workpieca material
Machining operation
Free-machining
and low-carbon
steels
Medium-carbon
steels
High-carbon
and alloy
steels
Grinding
Clear-type soluble oil, semi-synthetic or chemical grinding fluid
Turning
General-purpose soluble oil,
semi-synthetic or synthetic fluid
Milling
General-purpose, or
fatty, soluble oil,
semi-synthetic or
synthetic fluid
Extreme pressure
soluble oil, semisynthetic or synthetic
fluid
Extreme-pressure soluble oil,
semi-synthetic or synthetic fluid
Extreme pressure soluble oil, semi-synthetic or synthetic fluids
(neat cutting oils may be necessary)
Drilling
Fatty or extreme
pressure, soluble oil,
semi-synthetic or
synthetic fluids
Gear shaping
Extreme pressure soluble oil,
semi-synthetic or synthetic fluid
Hobbing
Extreme pressure soluble oil, semi-synthetic
or synthetic fluid
(neat cutting oils may be preferable)
Broaching
Extreme pressure soluble oil, semi-synthetic or synthetic fluid
(neat cutting oils may be preferable)
Tapping
Extreme pressure soluble oil, semi*
synthetic or synthetic fluids
(neat cutting oils may be necessary)
Thread or form
grinding
Taken f r o m :
Stainless and
heat resistant
alloys
Neat-cutting o Is preferable
Neat cutting
oils preferable
Neat cutting oils preferable
J . O . Cookson, An I n t r o d u c t i o n t o C u t t i n g F l u i d s ,
T r i b o l o g y I n t e r n a t i o n a l , 1977, . 1 0 ( 1 ) . 10.
Registered in England NO.
11860?S. Registered Office 52 crosvenor Gardens. London swiw OAU.
The Bureauistfevoredto r / i e s t u o y t t o w n i M t o t v r f c ^ ^
me Bureaus liability
mm^St^tlfwi^SI^UUunnSMnS
ftomwt
*îaDiiït fin respect of any^nhrmatton or any adv/ce wftarsoffver.
tarews
olra«Mc&
negligence) tfte Bureau accepts no
AOA-M/OIO
Table 5
TYPES OF CUTTING FLUIDS AND DISTRIBUTION
OF USE IN US INDUSTRY
Type of material
0
mineral oil'*
mineral plus fatty oils
mineral plus SFO
SMO
SMO plusFO
SCFMO
waxes'
fatty oils d
graphite suspensions'
heavy-duty emulsions'
O/W emulsions*
aqueous solutions
water h
minerals1
air'1
synthetics'
Cutting
X
X
Nature of melalworkin i operation
Drnwing Extrusion Molds Forging Rolling
X
X
X
X
X
X
X
X
X
X
X
X
X
X
x '
X
Tinning
X
X
f
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
x«
0
SMO, sulfurized mineral «il; FO. fatlv oil; SFO. sulfurized fatty oil; SCFMO. sulfochlorinated fatty-mineral
oil; O/W, oil-in-water type.
6
Light solvents and neutral oils, heavy bright and refined slocks, asphaltic residual stocks.
r
Petroleum, natural beeswax, compounded waxes.
6
Animal, vegetable, fish, sulfurized.
r
Oil suspensions and water suspensions.
' Mineral-soluble oil, soap-fat compounds, chemically active emulsions, pigmented fluids and slurries,
inert oil/water types, wax emulsions.
' Mineral-soluble water/oil types, soap-fat paste compounds.
h
Principal function: coolant.
1
Clay, eg, ben ton i te and kaoline, and lime, talc, mica.
i Polyalkene glycols, eg, greases, and emulsions.
Taken f r o m :
K i r k - O t h m e r , E n c y c l o p e d i a of Chemical
T e c h n o l o g y , 3 r d E d i t i o n , Volume 14,
Wiley, 1981, p . 5 1 3 .
— - -^«f^tianm;-'
yU;
~'Urt rt mi
f
AWL ercvp.
000M*7%II TOZJS-IOIOIOQO
Pvtum Preti Lid
c 111 Bmùh QccvpuioaaJHjYK» 5oo«r.
VaiM, N* 2, pp. U9-244. I9t1
sc fosure
t
ileura)
esburg
H » tod
ibcst os
Î!^
m r^
INDUSTRIAL SOLVENTS:
H
SOME FACTORS AFFECTING THEIR PASSAGE INTO AND
»
^
THROUGH THE SKIN
(other
EY, M.
M . G . BIRD
Essochem Europe Inc., Brussels, Belgium
ires oo
Abstract—There are numerous industrial applications in which skin contact with solvents may-occur.
An awareness of the nain factors which determine the passage of such materials inio and through the
sluo is important ta order to fully utilize, and not abuse, its protective role in the occupational
situation. These factors are illustrated by reference to some of the data and concepts available in (he
existing literature. Wherever possible, an attempt has been made to link these observations to the
applied situation and to highlight those factors and/or their combination which should be minimized
in good industrial hygiene practice.
I Report
i
'l* hat the
/I» normal
^nce?
,
nistered
t^v «ye«-1
ill
INTRODUCTION
w types
narized
i mineral
IN NORMAL CIRCUMSTANCES, when protective suits are not worn, the skin is the body's
first line of defence against the environment. It is able to delay and often restrict the
passage of foreign and possibly toxic materials into the body. However, we should be
aware of some of the factors affecting the passage or material into and through the skin,
if we are to use fully (and not abuse) the protection it can provide in ihe occupational
situation. In this paper I shall discuss some of these factors in relation to certain
industrial solvents.
.tin ered by
> .. al fibre
: )f gaslrobic :n tissue
hat. for
has been
s may be
THE SKIN
he more
ret
the actual ;
spective .jj..
.ratenliaTo produce. ^ ^
!» reacting'
\M xidolite
idustriaTJJ
y to fibres;7&
•-.A,-'
STRUCTURE
The skin is more than a simple shell. It is a complex arrangement of many different
tissues, smooth muscle, connective fibres, fat, etc.
A partial listing, per cm3, is:
3 million dynamic cells;
15 scbacious glands;
100 sweat glands;
1 yard of blood vessels;
4 yards of nerves;
200 pain nerve endings;
25 pressure centres.
The total surface area of the skin of an adult is approx. 18 000 cm 3 (about 18 ft 2 ) and
its weight (including fat) 9 kg or about 20 lb (CARRUTHERS, 1962; WELLS and
U'BOWE, 1 9 6 4 ) .
It is one of the largest organs in the body and certainly one of the least
homogeneous, varying from site to site in thickness and number of appendages (hair
follicles, sweat glands, etc.). The vascular and nerve supply and the connective tissue of
235
\o\
Indusiri
M. G. Biro
Strotum corneum
Slrotum lucidum
.Stratum
Moin bortm
toy*
Strotum «O'nosum
gf prcHle cet
loyer
Strotum
i v u m of b o w '
ce»
• -A. •
where:
J = the flu
3 = thickr
AC = t h e di
Dm = the d:
= strati
K p = perm
The per me
substances usii
u n d e r conditio
include variati
a n d any chang
The flux ai
of t h e s u b s t a r
corneum/vehi
air-filled inter
Indeed, the pe
the tissue.. Fc
solubility by
diffusion con?
Permeability
authors.
For the u
a«
a r r a n g e d t o resist direct injury a n d d a m a g e
•
fibres, cells and
^
. , , n c l l a y e r s a s i . l u s t r a l e d i n Fig. 1.
from distortion (CALNAN i * ^ d e r n , i s . e « s » s m dist.net la>e s
coherent
T h e outer layer of skm the ep
abou
,
^
es.desin , lh n
The main barrier funct,on of the eP
^^^^ ^ ^ stratum corneum
^^ ^ ^
m e m b r a n e of k e r a t . m z d
replacedtorn
a r r a n g e d in ^ " ^ " V o c c u r s in a b o u t t w o
replacement m the hum»n oc
filaments/tono-Waments
^
r£Sl
p u /„^
J ^
.JJ b
u
d£>up of
^
^
1
C
Jy
,n
of t h e s t r a t u m
enable nyo
^ surrounded b> a t
^ ^ kjratolytic agents. The
ket3l
p l e i n s with d.sulfide
bemg a m o ^ u s P
ces which
linkages, lipids and * a t « J ° l u b , e
corneum (WEPIEK* e
w e e k s
membrane
g
^
by
of the stratum
corneum.
n t 5C«lPTION
OF FENERATION
R O U T E AND T H E O K E T I C A L, D
ESCJ
OI h j d , „ p k
general, Fick's Law relating
state, namely:
Thickness
The flu:
Penetration
Stratum cor
resistance (
sites in thct
hydrocortis
factors of c
Skin appen
The coi
significant
important
overtaken
transepidc
That t!
P
j =K
i l , C » 1
We need
the importai
in Fick's eq
These w"
=
KJd)-^
Industrial solvents: some factors affecting their passage into and through the skin
237
where:
J = the flux or the amount of a substance absorbed per unit area and unit time;
d=thicknett of the stratum corneum membrane;
AC « the difference in concentration of the solute on either side of the membrane:
Dm = the diffusion constant of the substance in the stratum corneum;
K m = stratum corneum: vehiçle partition coefficient;
permeability constant.
The permeability constant allows a comparison of the penetration of different
substances using different concentrations and experimental techniques. This is possible
under conditions in which Fick's Law is applicable; deviations may arise whose causes
include variation in the number of appendages, different skin layers, blood circulation
and any change in the stratum corneum from contact aqd interaction with the solvent.
The flux and permeability constant can be directly related to the relative solubility
of the substance within the skin which is expressed by measurement of the stratum
corneum/vehicle partition coefficient (SCHEUPLEIN, 1965). The stratum corneum lacks
air-filled interstices and hence vapours must dissolve in the tissue in order to penetrate.
Indeed, the permeability of alkane and alcohol vapours increase with their solubility in
the tissue. For the alcohols, the functional hydroxy! group promotes even greater
solubility by binding to the stratum corneum, but with the consequence of lower
diffusion constants due to decreased molecule mobility (SCHEUPLEIN and BLANK 1971 )
Permeability data for a series of alkane and alcohol vapours are presented by these
authors.
For the remainder of this paper skin contact with liquid solvent will be considered.
WHAT ARE THE SKIN FACTORS?
We need to consider the skin factors, in particular those listed under skin s i t e , since
the importance of area of skin contact and duration are self-evident from units of "flux J
in Fick's equation.
These will in any case be mentioned later in relation to the absorption of phenol.
Thickness
The flux is inversely proportional to the thickness of the stratum corneum
Penetration rate differences are partly due to differing thicknesses of the barrier
Stratum corneum layers of equal thickness have been shown to have equal pénétrât ion
resistance (MARZULLI, 1962). Some of the variations in skin permeability of different
sites in the body can be seen from the work of FELDMAN and MAIBACH (1967) using C 1 4
hydrocortisone in acetone (summarized in Table 1), but it should be noted that the
factors of difference between sites will vary according to the penetrant material.
Skin appendages
The contribution of skin appendages (hair follicles, sweat glands, etc.) can be a
significant factor, representing between 0.1 and 0.2% of the surface, and they can be an
important pathway during the first minutes of dermal contact. This role is quickly
overtaken for most substances (other than large and lipid-soluble molecules) by the
transepidermal route (SCHEUPLEIN, 1967).
That the density of hair follicles influences percutaneous absorption is seen from
M . G . BIRD
238
TABLE I. REGIONAL VARIATION ON
PERCUTANEOUS PENETRATION OF
CI4HYDROCORTISONF
Location
Foot arch (plantar)
Ankle (lateral)
Palm (lateral)
Forearm (ventral)
Forearm (dorsal)
Back
Scalp
Axilla
Forehead
Jaw Angle
Scrotum
constant •
to 50'C.
Barrier in
Oneo
particular
stripping
absorptio
Gener
days folic
function r
Incrca
skin irrita
are descri
factors in
they were
examinati
of impairi
defective t
Relative
penetration
0.14
0.42
0.83
1.0
1.1
1.7
3.5
3.6
6.0
13.0
42.0
Data from FELDMAN and MAIBACH
(1967).
.M
studies by WAHLBERG (1968), who demonstrated, using a solution of labelled sodium
chloride ( " N a ) , that absorption was approx. five times greater from the abdomen skin
of the guinea pig than the ear skin which has far fewer hair follicles. In a similar
experiment, but now using a solution of mercuric chloride ( 2 0 - ! Hg), he observed no
difference in absorption between the two ^kin areas because the hair follicles were
blocked with protein precipitated by the mercury.
^
.i
'trt
-s
•V
It is pc
which affc
Waterjlipii
In rctu
considered
theor> of a
in lipids p;i
substances
While thi
characteri.-
H ydrat
ion-occlusion
The bound water in the stratum corneum is one of the principal factors affecting
skin penetration. It can vary from a normal content of 5-15 % to as much as 50% ir the
skin surface is occluded. Permeability can increase as much as four-fivefold in these
circumstances (IDSON, 1975). Hydration increases the rate of diffusion of substances
penetrating the skin (although water-soluble and polar substances may even be
\ \ impeded by substantial hydration). Application of greases and oils to the skin can
^increase hydration by preventing cutaneous water loss by evaporation (SHELMIRE,
1960). This effect can be accentuated by covering with occlusive bandages or plastic.
MARZULLI
coefficients
BLANK
primary ak
the perme.
coefficients
related to f
ether/watei
The flu?
molecule ai
such group
ionization i
extremes of
the skin m<
The importance of occlusion can be seen particularly in steroid therapy. MCKENZIE
and STOUGHTON (1962) found that hydration of the stratum corneum by occlusion of
the site of application increased the penetration of corticosteroids by 100-fold.
Temperature-humidity
The amount of water absorbed or lost by the stratum corneum is also dependent on
temperature and humidity. Low surface temperature and low relative humidity result
in a reduction of bound water producing a loss in pliability and chapped skin.
\
Changes in skin temperature itself can affect percutaneous absorption. BLANK and
his co-workers (1967) found that there was an increased rate of skin penetration of
" alcohols (chain length C 2 - C 8 ) over a temperature range of 5-50*C; the permeability
1
jl
Indullrui
tolvenU: son» f a c e s alTec.ing .her parage into a n j .hrough .he sk.n
c o n s t a n t of each alcohol increased, on average, 10-fold as the t e m p e r a t u r e r o . e f r o m . 0
to 50°C.
^ S S S s S M ^ T r t s
S p t r S r l
a b S
A
9
i a y ^ T t h e s t r a t u m c o r n e u m using adhesive t a p e w.,1 e n h a n c e t h e
n
2£ a,£ «
f
. ^ « f u n c t i o n is nearly restored t o n o r m a , in a b o u t 3
V ? i Ï s u c h T n i (MALK.NSON, 1958). Complete barrier mtegnty and
days following suen
rnsw»t
' " T c r ' e ^ m e S i
s o S
Increased ^ r m e a b . m y a . s
(MALKINSON
and GEHLMANN, 1977).
s T o m changes in keratin,za,ion o c c u r r i n g w i t h
, t e r a l i o n $ i n t h e s k i n barr.erpropert.es
h
skin irritation or
^
° t j c s ' H e a l t h a n d nutrition are i m p o r t a n t
are described later under -Solvent P r o p e r t i e s - H e a . t n a
weeks;
P
=
r
C
S
i
V
-
increased ( B L A N , 1964).
WHAT ARE THE D E T E R M I N I N G SOLVENT P R O P E R T I E S ?
It
is p e r t i n e n t to consider what arc .he properties and characteristics of a solvent
which affect its penetration.
m i n u t e to the sXin structure. we Have a . r ^ a i d t h a , it c a n be
m lipids pass tnrougn m e w
nrotcinacious content of the cell membranes.
^ Ï r Ï c t i r i s t i c L are i m p o r t a n t . V a r i o u s researchers (including T R E H E R N E . 1 9 , 6 a n d
M A R Z U L L r è ^ / , 19ôT) h a v e f o u n d that the c.oser t o unity of the w a t e r - c t h c r p a r u t , o n
coefficients, t h e greater t h e r a t e of_thc• J ' " ^
BLANK
a l c o h o l s ( C , - C B ) applied in a i m
o° b T a i n e d for a series of n o r m a .
SORTITION (BLA^M. 1964), f o u n d t h a t
c h c r - w a t e r partition
4
p r i m a r y
t h e permeability « i n s t a n t s were d. e d f c ^ ™
1
^ ™
, n b e truly
^ArrïMs—p———the
e t h
S
a
f l
ux ^
S
Ï
Ï
^
o
i
ï
such g r o u p s o n t h e molecule the
the skin m o r e p e r m e a b l e
AO*
24:3 • 6
(HADGRAET
^
o
n
|y factors c
between any p o . a r g r o u p s o n t h e
>
permcabilit)
a n d SOMERS. 19=6).
, , „ a d d i t i o n , at
fiiir^rft-5-*'*
VOCP
240
M . G . BIRO
In.
Mokcular
weight-structure
Little is known of the importance of molecular structure. There appears to be a
relationship between absorption rate and molecular weight. The studies of BLAKK
(1964) on the homologous series of normal alcohols in saline solution support this
(Fig. 2) and show over a 50-fold difference in absorption between octanol and ethanol
or methanol solutions; the permeability constant was found to increase throughout
this series as the molecular weight increased.
SCHEUPLEIN (1965) notes that this increase in absorption can be accounted for by a
parallel increase in lipid solubility and he and a co-worker suggest that, when a solute is
sufficiently lipid-soluble ( K „ > 1 0 ) , the aqueous regions of the keratin are less
significantly involved and the solute appears to dissolve and diffuse through a
continuous lipid network (SCHEUPLEIN and BLANK, 1 9 7 1 ) .
However, in another series of compounds (steroids), SCHEUPLEIN et al. ( 1 9 6 9 ) found
that lipid solubility alone could not account for differences in absorption of the steroids
which were within a narrow molecular weight range. These researchers suggest that
binding t o the stratum corneum determined by the chemical structure can impede
absorption of certainly more polar, less lipid-soluble, compounds. Molecular structure
therefore m a y not only afTect absorption through lipid solubility, but also .by
determining binding of the molecule to components of the stratum c o m e u m . Other
aspects of molecular structure not yet understood affect the rate of penetration and
GRASSO and LANSDOWN (1972) conclude in their review that molecular size docs not
appear t o be relevant unless it is of macromolccular dimensions.
Damaging and irritant
properties
Solvents can cause a marked alteration in the skin barrier properties (BLANK, 1 9 6 4 ;
STOUGHTON and FRITSCH, 1964) and this can be due to frank structural damage,
dissolution of skin components such as lipid, weakening of c o m p o n e n t binding forces,
irritation including cellular hyperplasia and swelling, or any combination of these.
I
This isc
Agents sue!
integrity of
used in poh
skin to proi
poisoning fr
of the area
importance
skin is vital
Low mi
penetration
is controver
shunts proc
SCHEUPLEIN
extraction, h
mixed solvethis increase
for, when c
without ren~
(VLNSON et (
Some of
the permeab
changes sue
separation fare consister
toluene, cur'
separation h
Solvents
N t N-dimeth
and that of<.
Octanol
Solver
I
Methane
Ethanol
Petroleu
Acetone
Chtorofc
Chlorofc
Permeobilify constant, VP I ©'cm H"'
for primary olcoholt m Jaime solution
Oato from BLANK(I964)
FIG. 2. The effects of molecular weight on the percutaneous absorption of some primary alcohols
Data fro
Magnitu
skin perr
(indicato
structure
Industrial sol venu, some factors affecting their passage into and through the skin
241
This i i ç h o n i ^ d a m a i ^ a s distinçrfrom mechanical trauma mentioned previously.
Agents such as caustics and strong acids destroy the internal keratin fibres and the
integrity of the proteins making up the cell membranes. The industrial solvent, phenol,
used in polynuclear aromatic e/traction has such effects and can rapidly penetrate the
skin to produce a dramatic onset of systemic toxicity. Incidentally, in cases of phenol
poisoning from accidental human contact with phenol in industrial situations, the extent
of the area of skin contaminated and the duration of contact are of overriding
importance in determining the f a ^ o f the victim. Prompt removal of phenol from the
skin is vital.
^*
Low molecular weight solvents such as ethanol, ether, acetone, etc. enhance
penetration through lipid depletion of the skin, but that their action is solely due to this
is controversial. This delipidization of the stratum corneum makes holes or artificial
shunts producing, in effect, a fairly porous non-selective membrane (BLANK and
SCHEUPLEIN, 1969). these solvents, which have most effect with respect to lipid
extraction have both polar and non-polar characteristics, the 'optimum* seeming to be
mixed solvents such as chloroform-methanol (2:1) and ether-ethanol (10:1). Even so,
this increase in permeability is also due to some other alteration in the barrier structure,
for when chloroform-methanol is applied to the skin and allowed to evaporate
without removal of skin lipid, a substantial increase in permeability is still observed
(VINSON et al.,
1965).
S o m e of the results of their studies on the effects of various solventsontheskin using
the permeability to water as an index are listed in T a b l e 2. These a u t h o r s noted cellular
changes such as alteration in nuclear m e m b r a n e s , vacuole f o r m a t i o n a n d cellular
separation following application of the c h l o r o f o r m - m e t h a n o l mixture. These c h a n g e s
are consistent with those reported by KRONEVI et ai. (1979) in their studies of n-hexane.
toluene, carbon tetrachloride a n d 2 - c h l o r o e t h a n o I ; nuclear pyknosis a n d j u n c t i o n a l
separation between the basement m e m b r a n e a n d basal cells resulted.
Solvents such as dimethyl sulphoxide ( D M S O ) . dimethyl formamide and
N,N-dimethyl acetamide reduce their own diffusional resistance through the intact skin
and that of other compounds which may be applied at the same time (ALLENBY et al..
TABLE 2. THE EFFECTS OF SOMF. SOLVENTS ON THE SKIN PERMEABILITY TO WATCR
Solvent applied to skin
Methanol
Ethanol
Petroleum ether
Acetone
Chloroform
Chloroform-M ethanol (2:1)
Data from VINSON et al. (1965)
Magnitude of effect on
skio permeability to water
(indicator of barrier
structure alteration)
Skin permeability to water
Solvent then allowed to evaporate Solvent then removed
(lipid removed)
(lipid remains)
0
0
0
0
Barrier destroyed
0
No effect
Slight increase
Slight to moderate
Very marked increase
Indu
M . G . BIRD
242
1969; BAKER, 1968). For D M S O , in particular, a number of effects are thought to lead
to this enhancement, such as changes in protein configuration, partial extraction of
lipids and substitution of D M S O for the water which is bound by protein.
SOME OTHER
FACTORS AFFECTING
SKIN
ABSORPTION
Species
Skin absorption studies are frequently carried out in animals rather than humans
on account of possible toxicity, but even subtle chemical and structural differences
between animal and human skin can significantly alter the penetrant properties of a
material.
In general, the following order of permeability is seen:
(ii) Where sV
easily an
(1978) wt
be avoid*
(iii) Occlusio;
skin and :
and shou
(iv) Solvents i
be ex peri.
(DUGARD
substance
preferablj
Rabbit > (mouse) > rat > guinea pig > humans,
but this is not consistent for different substances (IDSON, 1975). The skins of rats, mice
and rabbits lack sweat glands, yet have many more hair follicles compared with human
skin. The pig and guinea pig have been found appropriate animal models for a number
of compounds.
Soap
Soap has been shown to increase the permeability of the human epidermis to water,
glucose, etc.
Anionic and cationic surfactants damage the skin barrier even in very dilute
solutions. For instance, a 1% solution of Teepol and potassium palmitale greatly
increases the water permeability of the epidermis. BETTLF.Y (1961) thought that this
effect may be due to the uncoiling of the keratin filaments associated with the binding of
the surfactant to the protein.
Acknowledgemen
and Dr. P. Gras*
preparation of th
ALUNS v. A. C . O
Suppl. 4. 47 5
BAKFR. H . (19681
BETTLF.V. F. R. I H
BLANK. I. H .
BLANK. f.H.jml
S'
p. 245 (Edited
BLANK, I. M a n d
Bi ASK. I. H.. 9t iH
CALNAS, C . D . (1*
CTRRL'THkRS, C. (.'
DUGARO.P.H.IIQ
S U M M A R Y - W H I C H FACTORS MAY ENHANCE ABSORPTION?
From the factors described, it may be useful to identify some of those which together
may contribute to increased absorption and which may thus result in a toxic hazard.
Those factors are listed in Table 3:
TABLE 3. SOME CONDITIONS K>R HIGH SKIS ABSORPTION
(i) Lipid* and water-soluble properties about equivalent
(ii) Skin trauma/irritation
(iii) Skin lipid removed (for water-soluble materials particularly)
(iv) Hot/humid environment (for water-soluble materials particularly)
(v) Occlusion
(vi) Applied to site where skin is particularly permeable (e.g. scrotum)
Particular points of note are:
(i) We have seen that skin contact area and duration of contact are important. Uptake
can also be appreciable; for example, ENGSTRÔM et at. ( 1977) found t hat immersion
of both hands in xylene for 15 min was about the same as pulmonary absorption
during exposure to a concentration of 100 ppm in inhaled air for an equal period.
Prolonged and repeated skin contact with solvents should be avoided.
Hemisphere. \\
EN'CiSIROM. K . Hi
FumuN, R. J. an
GRASW». P. and L*
HADTRAK. J. W..
IDSON. B. (1975] J
KATZ. M . a n d P m
GILLETTF) Vol.
KRONEVI. T.. WAHI
MALKINSON. F. D .
MALKINSON, F . D .
Academic Press
MARZULLI. F. N. (I
MARZULLI, F. N., C
MCKENZIE, A. W. ;.
RIIHIMAKI. V. and f
SCHEL'PLEIN,
SCHELPLEIN,
SCHEL'PLEIN,
SCHELPLEIN,
SCHET"PLEIN",
SHELMIRE. J.
STOLCHTON.
R.
R.
R.
R.
R.
B.
R.
J. (
J. (I
J. ( |
J. ar
J. |{
(196
and
TREHFRNF. J. F.
(19:
VINSON, L . J . S I V , I N
7-19.
laduMfW solvents: some factors affecting their passage into and through ihc >kin
243
(ii) Where skin is diseased or damaged in some way, solvents will also penetrate more
easily a n d even aggravate that condition, as shown by RIIHIMAKI and PFÀFFLI
(1978) with a volunteer who had atoptic dermatitis. Contact in such cases should
be avoided.
ad
n of
(iii) Occlusion enhances absorption in most cases. The trapping of solvent between the
skin and an impervious layer such as clothing will also maintain close skin contact
and should be avoided.
hui ins
( snces
i ; of a
(iv) Solvents may well enhance the penetration and enable toxic levels of substances to
be experienced, which by themselves are only poorly absorbed through the skin
(DUGARD, 1977). In any comparison of the absorption properties of different
substances, a safety evaluation cannot be made unless relative potencies and
preferably detoxification and elimination kinetics are also known.
.
nee
jman
..V tber
-i
Acknowledgements-The author wishes to thank Dr. R. Scala. Director of Toxicology. Exxon Corporation
and Dr. P. Gra»o. Senior Pathologist. British Petroleum Company, for their helpful suggérons in the
preparation of this paper.
REFERENCES
to
ater,
dilute
e i iatly
this
ling of
f
u ;ther
r \ zard.
ALLCNBY A.C.CREAS£y,N.H.EiXîiNGTON,J.A.G.FLfcTCMER,J.A.andScHocK.C(t969jflr J Derm 81
Suppl. 4, 47-55.
*
BAKER, H. <1968) J. invest. Derm. 5 0 . 2 8 3 - 2 8 8 .
BETTLEV, F. R. (1961) Br. J. Derm. 73. 448 -454.
BLANK, I. H . (1964) J. invest. Derm. 43, 4 1 5 - 4 2 0 .
BLANK L R and SCHEUPLEIN. R. j. (1965) In : Progress in the Biological Sconce, in Return to Dermatolouv
p. 245 (Edited by A. ROOK and R. H. CHAMPION) University Press. Cambridge F r H i n j
BLANK. I. H . and SCHEUPLEIN, R. J. (1969) Br. J. Derm. 81, Suppl. 4. 4 - 1 0 .
BLANK, I. H . . SCHEUPLEIN, R. J. and MACFARLANE. J. D. (1967) J. ,invest. Derm 49 S O
CALNAN. C . D . (1970) Br. J. Derm. 82, 43.
'
' " "
CARRUTHFRS. C (1962) Biochemistry of Skin in Health ami Dise,**. SpnngJidd 111 T h o m j s
DUGARO, P. H . (1977) Dermatotoxicology and Pharmacology (Edited by F. N. MAKZI LLI and H
Hemisphere. Washington. D C.
ENGSTRAm, K . HUSMAN, K . and R U H I M À K I . V. (1977) Int. Arch, occur. emir. Hhh 39 I 8 M «
FELDMAN, R. J. and MAIBACH. H. I. (1967) J. ime>t. Derm 48, 181.
GRASSO, P. and LANSDOWN, A. B. G . (1972) J. Sim-. Cosmet. 23. 4SI V I
HADGRAFT, J. W. and SOMKRS, G . F. (1956) J. Phann. Pharnuic 8. 6>5
I MMHU-HI
'
IDSON, B. (1975) J. Pharm. Sci. 64, 901-924.
S ? «"c
of Experimental Pharmacology (Edited by B. B BHOOIE and J.
GILLETTE) Vol. 28. Springer, Berlin, Germany.
KRONBVI, T . WAHLBERG, J. a n d HOLMBERG, B. (1979) Environ. Res. 19, 5 6 - 6 9
MAI.KINSON, F. D. (1958) J. invest. Derm. 31. 19.
MALKINSON. F. D . a n d GEHLMANN, L (1977) Cutaneous
Toxicity (Edited by V. A. DRILL a n d P
LAZAR»
Academic Press, New York.
MAR ZULU, F. N. (1962) J. burnt. Derm. 39. 387.
MARZULU. F. N., CALLAHAN, J. F. and BROWN. D. W. C. (1965) J. invest. Derm 44 339
'
MCKENZIC, A . W . a n d STOUGHTON, R. B. (1962) Archs Derm. 8 6 . 6 0 8 - 6 1 0
RIIHIMÂKI, V. and PFXFFU. P. (1978) Scaml. J. Work emir. Hhh 4, 73-85
SCHEUPLEIN, R. J. (1965) J. invest. Derm. 45, 334-346.
SCHEUPLEIN. R. I (1967) J. Invest. Derm. 48, 79-88.
SCHEUPLEIN. R. J. (1976) J. invest. Derm. 67. 6 7 2 - 6 7 6 .
i
iTptakc
imi srsion
,ufpt»on
I period.
i.
SCHEUPLEIN, R. J. and BLANK, I. H. (197!) Physiol. Rev. 51, 702-747
SOIF.UPLEIN, R. J. BLANK, I. H.. BRADER, G . J. and MCFAKLASF, D.
SHELXIIRE, J. B. (1960) Archs Derm. 82, 24.
STOLGHTON, R . a n d FRITSCH, W. (1964) Archs Derm. 9 0 . 512.
UFIIKRNG, j. F. (1956) J. Physiol., Lontl. 133, 171.
L K S NtiER
Kw:HLa W R L l AS
M9
'
-
''
J. (1969)
J. invest. Derm v
"
63
0J
-
-' " - » " .M.D.andMASi-RAT1T.(l965)roA-/fiiW/.W-««f.7,
1
\o-\o
I
I
i
An*. or«vp Hrn. '
M . G . BIRD
244
WAHLBERO, J . E. (1968) Acta derm.-iener,
Stockh.
Pnntvd «s Grai B
48,
WELLS, F. V. and LUBOWE, 1. I. (1964) Cosmetics and the Skin. Reinhold, New Ycrw.
WEPIERRE, J. and MARTY. J. (1979) Trends Phnnnac. Sci I. 23-26.
*
DISCUSSION
J T SANDERSON • We know thai transfer of solvent vapour across the alveolar membrane can be increased
several fold by increase in work rate though obviously the solvency character of the material also has a major
bearing. Could you comment on the likelihood of a similar increase m percutaneous abtorpt.on due to
O N THF
1
' " " M ^ °BtRD Vanfnot aware of any published study on this aspect. My thoughts ar; thai ihe increased
work load would result in increased perspiration and hydration of the outer epidermal layers. Occlusion of
the skin prevents water loss and the resulting hydration of the epidermal layers is thought to be a mam factor
in the increased percutaneous absorption of most substances under that condition. Similarly, any increase m
hydration caused by the work rate might be expected to result in an increase in absorption.
W. H. WALTON: Are barrier creams any good?
. . . . . .
L.
rr . a
M G BIRD- Opinions differ widely about this, but I believe the general opinion is that they are oNimited
benefit The correct barrier cream must be selected, since applying a water-repelling cream when handling
oils or lipid soluble materials may actually enhancc contact and increase skin absorption. Another problem is
the false sense of security their use may give to a worker who might otherwise limn >k.n contact ; conversely
though, their use may actually encourage proper wash-up at the end of the day.
J S. GARDINER : Is your opinion on the usefulness of barrier creams in preventing skin absorption based
on any good scientific information?
M G BIRD- No my answer was based on opinions I have encountered. The .«formation 1 have found m
the scientific literature so far is very limited, but it may be that manufacturers of barrier creams have such,
information available.
.
.
r
B S THOMAS- A relationship was drawn between diffusion rate and molecular weight for a series of
normal alcohols from methanol to octanol. To what extent is this also a water solubility effect and would any
effect be expected for steric hindrance in the isomeric alcohols?
M G BIRD* Yes ! referred to the work of DR. BLANK (1964) on ihe penetration of low molecular weight
primary alcohols in various vehicles. His data showed that the permeability cotwanl increases as the
molecular weight increases through this series when penetrating from ,aline solemn. It is suggested that, as
the solubility of the alcohols in non-polar liquids increases, ihe rate of penetration from aqueous solutions
also increases However, it is considered that the combination of lipid solub.hty and *.uer solubility, as
reflected by the water/lipid partition coefficient, is the important factor in the percutaneous absorption ofr
these compounds. 1 would suspect th.it the structure of the isomeric alcohol. m.i> «ell influence their
partition coefficients, but 1 do not know of data describing their diffusion rates.
T H E DUSTS WL
chial and alv
described coi
inhaled throi
functions of
hypothetical
particle in qu«
the fraction t
where d is the
and l{d) the in
as that fractio
the body thro
concentration
controlled lar;
comes down tt
working assun
then can the c
follows, thereft
loss of particle:
the subject, cv
Fine partie
follow closely t
the same argur
instruments. T
strongly in the
&
to
f]
Sir"
M
T
V L
130
AL
O M A R .
(
O M ' I
S M . A / \ R
\ M ) R ' I M \ < I !
| K \
Ijh/c : Results of the qiicstionn.nr-; jh« *.i* r-pvs ol
work. Ii»eal:/.iii<"i •=! the lesions ar.dii.nxj' tvpe
The series was prepared with the help ol patients»
chemists at one of the most impoiunt companies in the production cutting Hinds m the Occupations
55 -JI l
turners
country. Its composition was based on .1 ioni- 1 eel «hers
s<. 1 :4 '4'. 1
:n » sJ h*' ; i
prehensivc survey i>T the components ol cuttinc lathe opcr.ii«»rs
44 c 1 > • »
mechanics
oils most oltcn used in Spanish industries.
« t; 1" • »
foundry «otkers
The list ol" 2f> materials is shown in I I .thlc 3). uenerul inet.illut
«H ( :i ' 1 1
Thev are divided into the lollowinu groups.
I oeali/aiion
14.» if.: 1 i
3 mineral oils (1-3)
«.It«rsa of h.uuls
55 t2- '»!'' I
palms
2 chlorinated additives (4. 5)
h*
1
forearms
3 sulphurized additives ((>-*)
iq
1
\
h
)
fiiKcr tips
tx i '<:'"• »
disseminated
!',i/ fi- I.
* 11>' 11 ii.iiiv'
L : 1 K.11 iv IK
I »pe I ji \ 1 : 1 >"ii- p.tpules.
( UllIM^ Oils .liulv
• -ri .1:111» ami .I--'».1 i*l han.is
O1
'Kar ><1 \hkK
( ;isc ii.i
Pulfh lest writs: nil M 'ties
I \ PE
( inpn i I lu^pii.il a iik'i 1
|'\ pC 111 WHI k
1. turner
2. leHifiir
-
1 PIIL«
I.T R : - . . N D >
.NUL
l-.eer»
1 \pc » 'l'i'ir. p.i'-M.if . • l5--tiMi1.il
I
IV
...VIM
-v
> fs.i t
is •;..! J. 1: 1 nus
.:
>UL E .
-N
1
^(-.-••1 1
'
'
s-, ,:s ' S ,
3 U" <• .'IKT.Il-T
4. mci h.iMK.
5. I'ouii-li \
f>. yenu.il uui:illnt-.\
Clinical
puiure.
loiali/iilioii
1 .1111111.»l !.ii
5 cimilsilic > ( lu- 14)
Juisinn hands
.S ^crmicidcs ' I S 1^»
palms
4 glycols i:n-:.M
1'orcarnis
2 pbosph.itcd additives (24. 25)
c.\chisi\eiv linger tips
I trielhanolamine (2b)
disseminated
They were tested in appropriate concentraTypes:
tions.
The cut line lluids handled b> or y-.cd m
iirylhcmatoiis papulo on lore.nu» .nu» .I-MM-MS oi
ihe
patients
work were tested as loilows.
hands
2. Vcsieo-papnlar
"" hands and linear»
nmicralt'ils
diluted t-1
m olive oil.
3. (,'hiomc cc/cnu. luIk-iuIk J .nul l i q u i d on palms
soltihlclMls
(cutting
oils)
in
use
concent rati' n - >r
4. Discoid eczema t»n hands .nul l«»ie.»rms
10'
r
ip
aqueous
>olution:
I ime "1 evolution:
1. <3 months
tats diluted i»»
in olive oil.
2. 3 months - I year
3. > I year
StaiuJaril wr/Vv
Test results
Standard scries: 4M h. 9h h.
I he standard series ol the Cï!:!I)C was applied
Oil series: 4K h. »>ft h.
to all" patients. It consists of 26 allergens inOils used by patients
cluding M I'I' the 1 ( DR(i series and others
(lesnlt »W> hi
accepted by ihc Spanish Group.
mineral
cutting oils
I a is
1.
m
ofdH'AIIONM DI HM MOSI s I ROM C I rnv;.<>ns
H types of
:al type (230
TtihU' J. Oil series
i
1
i
>x 23.91'.; )
5A < 2 4 . 3 4 ' - ;
;
\
)
> (X.69'.'>
;(i9.i3 r ;>
.. t i m )
50 (21.73'* >
\ v-hi Je,
Material
î
4
j
5
<•
\
*
aromatic In| ( , i
p.n ,i 1 : i;iit. «'il {51»' . )
piiphthcnic oil ( 50' i l
ehlorinaied line.M p . n a l i n .
l;itl\ oil '-chimin,ited p . . r . i l i m
vejicl.ible oils 1.»' S
l.i1t\ acid sillfm i/eil 1 ' '
pol\s{ilfi)le o r j j . m n
r
• (62.!7 > l
>5 (IVM'.'M
hi (29.M'; )
» DF».^5R; )
IJJ w
ll.
soap
11
p<»t
i :
\\
i l ikU'
l:i! I
r
'*i ; )
S7» l . l " . 3 9 ' .
\l<
l»l'l./«
1 7
Mill •
«'llW
«II \ !
oil
oil1
..H '
• •ii '
Ml
1 L!LVLI-' l l
1 « l i' sItV
. • h u
J.il»'
Oil
Ol!'
••1
sir ,
i-i' ;
<>)• :
1'•
.
' !i
In
,
t'l
.
i'»
,
II1
In
.
1"
>
k
i'
•
•In .
I ; • • \. i I, \ . I '.
» 111-. ! 11 N I 11 v.
• CÎ. "I
!
)
j (12 ••<"' ; )
1
. » 11V c
.•!i\e
MlllolKlU-
• ll.M/.il
1
o l i M
• "1
.ilk.ini'l.nnMv-
11 l . l t f . ' .11 111 I ' l l H - V
1 * I. l.Vlnln
•
( 1
i«MIIIN II.I|'!IM'- «Î.II»*
! • 11\ .II'II.K
|H-l|.>k'il'H
'
> '|i\ c
1
It
oil
olive oil
iilivc ' . ' l l
ollW
( '< ' I K C I l l f - t ! M U I
)
ill. •• ;ill I.
i.llllll t !
iim.i-
Discussion
( '/tmctii pailcrn\
i
">neenira- o r u s e d in
To
»ws:
til;
ntrationor
Using the clinical cl-issilication recommended
bv Squire el al. reported by Caln:tn (Un.
tried to classify all palienis »ni»> J gioups:
(ii)
(b)
erythematous papules mi loieann>.
papulo-vesiclcs on lundi» .nul linuei'-.
(c)
chronic lichcnilicd aiul lisMiied palin.n
(d)
r g e n s inand
others
MI.
-^clhresin
»
/'i/v I. l.'rviih'»uto;n pontic* <"1 'nrcur»i\ anJ
<tiu\,i of haiu!\
1 his w pe is not t n i K i i / . - n u t o n s and .ille.'is the
dois.i of ihe lumls ,tnd wrists more than the
loicaims.
Ihe lesions frequently disappear even \u:h-
ec/ema:
miii .1 change of uork. and sn *pilc of >omc
discoid cc/.ema on dois.i <«l hands and
lUluni;. do not incapacitate ihe subject. Sometimes. Iumc\er. H i" ihe m iial st.ice ol di»«.oid
ec/ema (type •!). »
finpers
»s a p p l i e d
purent .i» cl I me.11 \ A I . I . I ni v . N
the vnne patient.
Ihe lasl section was modified. subsuming ihc
word forearms lor finucrs. whn.li aie included HI
ihc dorMim «>f (ho hand.
These clinical forms arc not so dillercnt .nul.
although il is frequently possible t>« classify the
process in a sufficiently defined l'on», they are
manifestations of the same process am! could
I iNihcniaioiis m^culo-pajm'cs. morc-oi-kss
lonhucnl. can bc«seen although not well-defined. In our survey'. 24r : .if the cases had this
presentation. Positive test< «ere not common,
cither in the oil series OS' ; > or in the standard
series (47.2';t. which Micuests that it is an
w
1.12
Al OMAR. < ON1>! S \l A/. \R AND ROM AGI TiRA
irritant type or the first phase ol type-4 discoid
ec/ema.
the standard series, thus showing its relation to
metals.
/i pv -f / ' / • i :cin<i n>i-Jnr\cnf ha>uh anU
farcarttw
Tvpe --ftipuh'Vt'M'ch'*on hunJ\ ti>uf finger*
This type, although very spectacular h\ its acute
and exudative character, is not so easily identified with soluble oil pathology as the previous
or discoid types..Its relationship with the fluids
ought to he frequent. according lo the basic
ideas of contact dermatitis which state that
fluids have a tendency lo give dermatitis in the
interdigital folds, but our experience suggests
that it is more frequent in patients with poIvsensili/ulion to metals etc. Some cases show a
dishvdrotic vestibular picture, which may he
This pattern is ihc most frequent in the effects of
cutting tltiids. as Rye roll found ( 15». It maybe
minimal in small plaques or very intense, diffusely afiecting almost all the dorsum of the
hand.
The lesions are cc/e matous, with an cry themalous^base and slight superficial scaling in
clearly \ isible plaques with a defined outline. Il
is most'lrequent on the dorsu of the hands and
f o r e a r m , frequently sparing the flexor aspect,
although nol be:ne a strut rule.
conl'u.scd wiih a dislndrotic pieces- set• 'iidary
Iliis i*-sometimes siipei imposed >>n a inivi"bial iTumniblai ec/ema. in which ihc levons .1 rc
to tinea pedis. This pa'.tern is -.noie try nient m
summer, when ^wealing add» to the edema .-l
ihc dermatitis.
This form is the most frequent i
n»)'"; \ in
the '.ases studied, but the incidence ol positive
ivac:io;: to mis is oiilv 4|.S f ;: the sl.indatd
set ics was positive in
i olYases. thus di-.wing
ils ielation:»hip with positive reactions lo metalv
less 'numerous. almost always \esieuiar *ith
yellow; trusts provokeJ by bacteria p.iraM'.Mne
I he c » 'id.itc. some Ic'si -n^-mU! ha\ c .1 ondarv
contaiMination by cutting M'jid». pre-.r.iing =
. n
identical appearance.
I hi.-* climcai l>pe had the m"»t
-1; !•>•.:
icactiv'*'^ to the oil >er;es
),
•\ln*»st aii :hese clinical patterns t oi:ld he
attributed to :n irritant dermatitis as muJi a*
Type < 'hronic ti< hcnithi/ ami m^z/v»/,'ut/mnr
an allergic one: attributed
of patients
studied. positive to nur oil series, to I he second
iv-VM
ï h i s allccls the palms ami luigei tip> ol both category•
ha nils, although a higher degicc ol involvement
of the right or. leu hand is Irequeni depending
1
Results
on the patient's handedness.
Patch tr\ts - m tin./-in/ \cnt'\
The thickening and dry no-.» of l!u p.dinar
The paltern ol positive responses 10ihe-.l.indard
stratum coineum ai'd ils sjij.oine m areas ol
flexion, with the apfvaraiuc ol lysines. which
series of the <. il .llX' I Table J) is quite similar
ill some cases mav be deep and eM te me I y lor ^het } researchers. The following allergens
painful, leads to little doubt in diagnosis. When
were the most frequent in metallurgy workers
it presents as red hypcrkcialolic plaques. dewith ale 1 matitis.
ferential diagnosis lioni psoriasis or a neuroI\mtp*envft-/te<htiivine fPPfUt VJ fIV.l''- t
dermatitis must be made.
The reason for this high number ol reaction* to
The presence of psoriatic lesions ei-cwhere
W ' l M is not clear: its presence in the oils is not
does not completely rule oui an occupational
factor inducing the palmar involvement < Koeb- frankly specified. Its presence is suspected in
rcfincrv oils, although react • ns could be
ncr reaction). This was the least common manicaused*
bv cross reaction with other amines
festation ( 12.6'/;.) hut these patients had 44.S';r
frequently
present in cutting oils. PPDA is used
positive reactions to.ihe oil series and 55S to
L
133
OCCI'I'M ION.AI 1)1 KM \ I OSI S I ROM ( I T U N t i Oil S
table 4. St.oulanl sciies Ol MX pmitiit' umiIk lll>
' , ul pi.MliiVs
( 1 I'M
chronic
u
lanolin
ol l o l a l
1:3m
1
ii41 •.; i
;
11 ^ i
:i.s '
cokih
thiuiam
No. ol
paiu*ni\ •
3(i.«) '
[TO A
caine mix
p.menis i.M "}". >
•
M 1.3'^ )
i4.:'
;ti '
.v-i ' ;
li 1 ' : )
* *
lg :
nickel
If llî.l! JcllVikin-i'iiivv
i»« >li >|>li.
mcreap.
-Cl:>!c.
•
' •
• iiciLiirv
.-lllpiil.s
« ^"
I'PI ) mix'
Turpentine
<: I i
balsam i>l' IViii
11.3r; i
in the synthesis of ben/isothia/olonc tpcisonal
communication).
In previous studies carried oui hy CondcSalazar on 76 metallurgy patients, paraphenylendiaminc occupied 3rd place I Ml.2' « l
( hhiim-. > obii/i. anil nii kc/t
Metals occupy a prominent,place m the reac9
tions obtained. Pnta.swium tlichr<<iiniti is 2nd
r
with
; . In 3id place is coluill (hl<>n,lci I 1.3 j I.
The other indicator of sensitivity in metals is
although the patients were not selected for
possible contact dermatitis.
tiiiki'l \ulhi,ft* which was in» Mh place in the
In Alomar's series of patients, who were
specially selected.TIM)A gave the highest num-
C'hiome has always been,.noted in publications on metallui^N workei's; Uud/ki et al. i IS)
ber of positive reactions I 14 om <>l 35; oi 4ir ; j;
the rate was 35.5'r in the series ol l/omlcSalaiar and 3 5 . i n that "I Koniaguc»a.
loiiml I ? positive cases out ol 125 In .i >iuJ\ hv
( o n d e Sala/ar (personal communication) it
oci upunt I si place. wi\h I * 2',i ot icacHons, and
In the statistics published hy ( i l - I l K ' in 1477
(I?--. PPDA occupied 5ih place in general with
in the ilT I H ' statistic of metallurgy workers, it
presented P . S r ; (17). This, high incidence' of
9.9'Ji ; and in exclusively occupational eases.
10.4^ in metallurgy winkers.
p.i'ilive reactions • > not due to its pi esc nee as an
ii!i;niiiiv in the lUrid-». as Sa in it'/ À Kai / t 19 land
ijuc.siionii.utc with only 3.YV \.
w
134
Al OM \K. (OM'I S \1 A/AK \M> ROM \i«» I R A
possible origin ol the reactions: they are evenly
distributed in all occupations.
Uutthirn Wm «5.2'.' » which is m 5th pl;ue is
composed
«M v a l i o n s rubber components. I be
indusit'v'.
reactions
in
out patients arcduc to sensitization
The question was not spccilicallv asked, but
hv
rubber
gloves,
normally on damaged hands
our suspicion is based on the I act that the
as
there
is
no
direct
relation with Cutting fluids
majority of positive reactions to potassium
The fact that most sensitivities in relau- n !••
dichromate ami cobalt chloride are contained in
the group of general met a II ni g y w 01 ke: s, 01 i he the localization cottespond to the dorsa . i 'he
hands, an area frequently sensitized by gloves,
group of labonters who are unskilled, and U is
supports this thcorv.
possible thai they pieviou-ly uorked in conIn seventh pla^e were "»»"/»hi>!.\ i4.3'struction.
I'rcuucnt sensitizer in \-.nn It- --ngin i- pr>nC'alnan i 2 h rcpoiu-d a patien; u h o was
Cipallv ;ittnh:i:ed to cream- «..•-uicttt.s. more
sensitized lo ehroiue with no pievunis a n u \ e :
than to occupational expo.su re. ^e s!o n -i k'i> -w
dent: i n o i c w t the oil used contained <l.S .
>•1 .iris !,:,;t!.-n \s ! » f i met.i'i'ifC) . : r l ci .. it:i.":
potassium diehi'Miiaie as an inucor io-ivc:
lliuds.
however, -nu contact with Spanish manntacI m "h/'./'/i : .A- w - >nl v a lew tea-. 11« •"! *
turers asMiies us thai il i- not used in ilm wav,
s
:
In sel ie « no. I i A !o:11.11 I. i h ( oji11* w,: - n..; >. > i .'.'>'i. Il a i! • ; j -e'is.tizer. I here has !\-:n
Ircquentlv poaiivc a-, m the *-eiies •>! i .>rMe
iniii.h di-.'i;->:- n ab«- at the poss;h:l-:v :ii,ii
Sala/ar a:ul Uomague:a. w b i j i is
.ii:e
loitn.ddclr.J:
;:crmic:d'.-s sensiti.••„• *.<:
h
tinreason
pi.'.
•
real
r;i>:;iph»!vp ha- "ven
to the I;K; ( at the no. 1 patients -..vete all
found.
•
qualified inel.illuigisis,
i f- ;\iii?r.!- !'•..! p. '-i'.iv •. r.-.ie'. :on « i - • he * .th;. ( i.huh t-ia\ -H- a -v:i-.ui/er eor^ouui.-ut with
dro-l
.v*
i T hv.'.-o»y ;;h.\: .m: i
" were
chrome. ivcaioe >•!
Pic-e:'...c in S;v.:i:sh
po-11!v
v
t..
.!.-.
and
5
:o
h.»;
1
»
-ubcement: the p r e s e n t
vbah m
^.nt.ag
l-inarsson et al. (2(1) claimed, hut to contact
with chromemetal material, or possible previous sensitization from wot king in t!ic building
fluids is also high. a> it is iclcased I rom tuneaten
alloys which are used to lorm a const ant cutting
edge on the tools (20-22). At the end of one
day's use. a concentration of 40//g/g ol cob,ill
can be detected.
' The studies of ( o n d c S a l a / a i placed cobalt
in 2nd place with
and in the (.il-1 DC
statistics II,?".' ol metallurgy woikcis piescnted sensitization it' it (17).
sianees.
4 substa.Kes pre-ented
ol positive
results: neomycin colophony, mercapto-nut
and etl»ylcne«!tamine.
.Wf//Mivm is used topically. It is a known
sensiti/eV. but i> significance is not important
in this'study.
O'infiJt.'nv i- l'U sent in some lubricants, and
anli-iust oils io give them adherence, and it is
occasionallv used as an emmulsificr in coolant
I he reactions to m\ kcf 'did not >ecni so
oils. It uus be an occupational sensitizer,
significant
Nickel is a vciy frequent
depending on the tvpe of oils handled.
allergen in any sampling, occupational or not. it
Mfi'ctipin Hii.x could sensitize by contact with
is not us important in the métallurgie environrubber» but the use of mercaptobenzothiazolc
ment. where it is present in non-nickel, releasing
a> an aijiicorrosivc »s al:-o known, especially m
alloys.
Cainc mix ( 7.4',ï.) was in J(h place. I his mix- copper working.
/.'thylcncJidinrnr
has provoked a series ol
ture of local anaesthetics contains amcthocaine
reports-'in
relation
to culling oils. -A direct
and bcn/oçainc. the latter usually being the
relationship
with
theods
is not clear. However,
cause of the icactions. It is an ingredient in
the
germicide.
I'roxel
'
CRL.
ii formulated with
many antihetnorroidal preparations. I'll is is the
»»
WA
OCtfPAMONAl
;
vcnly
' ice is
. The
ization
t^ 1 hands
inj uids.
».on to
• i of the
by oves.
in
îen
I
.3 '7,
), a
ITT
prin-
tic
more
'l know
.«ming
.étions
135
IH KM XlOSl.S 1 ROM ( I I I I N ( j OH <
an aqueous ethylene-diamine solution and 33' >
of 1.2. bcn/isothia/olone-3-onc < H I. 1 . p o s sibly this is the origin ol most recorded sensi
tizations. as fv'S positives were common to
eihylenediainine and Ivn/isothia/oloiie in the
oil series.
Possible cross-reactions with oihci pokamines present in cutting lluids has been suggested: diet h vlcnelria mine, trielhyleneiéti amine. trimcthylhexamethvlenediamine and even
triethanolamine.
The rest of the positives do not appear
sufficiently significant for comment. due to the
low number ol results.
significant. showing jlood correlation with the
reading at 4S h. whieh confirms that the concentrations used to prepare the series j r e appropi.ate l!f the test had been irritant, the
reading at 4N h would h;ive shown more positives than al
h.l
(Bll I is mostly known by
the commercial name-ot Proxel' I'he Proxel'
series ol ICI are germicides lor the presei vation
of emulsions of .synthetic pokmcrs. paints,
thickeners, aqueous adhesive*, textile solteneis
aud culling lluids.
Several types are kn.»un t i t I pamphlets R4Hi'n:i\othiit:olnne
Piovs-l AN: aqueous Jtspc'sion with >3'.
I'lllt /l h'M \ nil \,-l h \
!tl I
! he results are shown in I ,»Me ^ 1 IK MM -di 'u .•
of positive results .it
I» ( i "
i is niehk
Ptoxel C11 N: aqueous Milut.o:i ol dtpro-
pvle::cj:1uot - 20' : Hi Î
is b e e n
ilit
that
—
; for
I'uhh
Oi's relies. posiiiMs »>». h I!'»
been
ih
ahy-
Hc'l/ISOT |l M/- • I « 'in.'
ill-)
J » f.
9 were
h sub-
Irielhjtii'l.nuii'.i'
M^sitivc
hciahvdro 1.2 1
iiis 1 ? Ii\ilri'\> clhvl) tua/inc
uo-mix
**
town
i
portant
.and
nd it is
:oolant
sen tizer,
•Ml'>
.-fl l.'Mt
. J in,
I
U
vc gel able oil.s
jlkanolamitte
IIcxylcnc glycol
1,1
i •
l'y* ' '
11: i
«.I ' •
iw •i
ear.
let with
wt izole
•vr
i|y in
iilkylhen/eiir
sulphiniaie
hp. 14X7 iiino
butylmorphohne
liieicsyl phosphate
hexahydrotria/ine
derivatives
naphihenic oil
; " -s of
A ircct
owever,
:ed with
linear ihlonnaK-il
pa rat lin
laity amide
propylene gl>iol
SJ
t:
;»
4 5*;
\ t,
113 ' ; >
M
\VÔ
ALOMAR. (ONDI.SM A/.AR AND ROM AC MTR \
136
Proxcl C'RI.: aqueous .solution of L- 11 » \ I c t > - Tricih,itwfjmirn- in second place appears with
42.1'\ of positive reactions. It forms an imdiaminc + 33'/r, BIT.
portant part of the formulation ol soluble
Prowl XI.2: aqueous solution of propylenelluids. as U may be 15 to 20 r ; in emulsitiabl?
glycol+9.5% UIT.
fluids iufiiie or nuiky soluble oils) and up 'o
Proxcl I N. MIT f t r i a / i n e
/ active agent )
40'
i in synthetic tlutds (green or clear soluble
All the products are highly initaiu. Repealed
oils).
contact with the skin can cause sensitization.
We used a dilution of | 0 r î in water, which
In the K'l pamphlets, it is recommended that
may have an irritant capacity. I here
m»
l lie product slum Id he used at a concentration ol
definitive.concentration:
some
authors
test
at
0.07 VJ in cutting lluids: if it is added by the
T
|0<;.
others
at
and
even
at
2.5';
l24-25i.
maker of the lluid. it should not eweed u. 5' «'.
although thev disolve m petrolatum. 1 lanto he later diluted in water to ID !
nukscla ei.ul. I 2b» give validity to results at 2 ' -.
At the begining of the study, eoneentralious
All ihc>e studies have been carrieil out on the
of H I T at I ' i a m i al U 1 \ ' were i n c l u d e d . : h e
r
basis
of the
I '< ctincentf alioti was w it lid taw n as the iiucn• » presence of this suhtanee as an
sit v and 111*« | uei i e v ol I hi- o i « -l'i- i espi -n-e- • h-•:tiiuUi| if t, m v 'smi- ho
We believe ! C >r - ; - a l i d . a - only 4 ' out o: 2.-'»
cated il as to.xic.
patients re a. ed po -i : i \ e: \. a :id '.he leadings a '
The concentration "1 '). i ' i seemed .ideijuaie
to -«tudv possible s»;nsiii/aU"ti. il t epi.. ••er.ts 4S h were -mly p^-iiue in 4 | patient-.
In 3 rd place : « the -11 bs t a nee known à '43.<>','« >»f the reaclious'in the <«il series.
r<
I he scnsiii/mg capaetl> < -I iln- -ubstanee w.i- he \ wh'fi I .»'..« •. •*.*•'.-1. i > \ \ eth \ h
(Cool.in UK ' • with ! ; 5 ' ; positive^. Tin. 1dcinon-iia'ed hv a nia xiini/aiiou test in aîb'no
widelv used and h ^eeti the si-.bie.'t of nv.:n>
guinea pigs. Products with MIT were well acpublications < 3 ; ' I lie maximization .studies
cepted in Spam brforc our study, loi ihvir Irgh
with Cirofau Ilk" wotiîtrmeda moderate degree
qualitv as a hiocide. Togc'hcr with poorconirol
of sensitization t33). similar to that obtained
of its concentration in Ihmls (it is Ircqucnl '.liai
with BIT.
germicide is added in quantity .-without special
In 4th place with
.' of positive results was
control, in those tanks where hail smell, puticitlkanolanunc wveiubtc fat*; an emulsifier comfuction etc. have hcen noticed) this allowed
mon in cutting fluids, where it is possible thai
direct contact with it at higher concentrations
than recommended. In I MM. 20 tons of HIT. 1 the alkanolamine component is responsible h»r
the reactions.
tons free products and 13 tons in formulated
I/cwIene c/ri-o/ t'*-nu-ih\i-^.J'pcnianah"l)
products, were used in Spain.
appears in 5th place wi:h S.I ' p o s i t i v e results.
The skin is altered by constant humidity,
1'his seems odd in view ol the sensitizing power
alkalinity -and microtrauma, facilitating freof pol\glycols-, a would have been logical to
quent .sensitization to Mi l .
expect more respon-es to propylene glycol, with
Den/isothia/oloue is a substance with high
its smaller molecular size.
irritant power, pussihlv due to ii> alkalinits at
pi I 10. anil moderate sensitizing power, according to the Magmissou & K ligman scale ( 23 ).
f
iI
1.2 be'i/isotliia/oliii-.^-one
Petroleum \u/fhr.:ie. i'hre\il phn\phote and
MP. 14X"? Nilrobuivliuorphohne. represented
6.3 r ; of positives in the total reactions obtained
with the oil series. Petroleum sulfonate is included among the emulsifier-. Tricrcsyl phosphate is a phosphorated extreme pressure additive but now little used because of its poor
performance.
pitr.\
ti/.
;ri,i:i':c
•v<_ •
a f! i •
I:
Rye;
un( *
how
the pal
pi-- :
W
the
the
dra
( K< •
o<:
aci !•
51..'
.In
dc.
firs i
L
WA
(X ( I T \ I ION AI 1)1 KM \ I DSI S I ROM I'l l ! |\< i D| I S
n
with
an imprt,
•is
uble
able
up to
soluble
i
lich
is n o
7» I
(2-
t at
25).
Kan-
I' 1%.
i c
rhe
1 he irritant power ol B!\I4X"> nitiobutxlmorpholinc or Hioban P-I4X? on the skin is
known (34) but ils usage dilution is not aggressive.
Other derivatives of hc\it-hvdrntnazitw
complemented with fungicides showed 5.4' i positives of the total. I'he complexity of these
compounds is possiblv the cause of the sensitization to (hem being not so Ircquenl as to
Grotan BK".
N(tphthenic oil, u pure oil. showed results at
h which have been considered as positive,
although with slight reactions ol nnl\ one r
they are dillicnll to evaluaic
as an
1'iitih ie\t\ - , uuuim ;/iu,/\
U
In the scries I ( Alomai >. !he nu uU n> e oi
positive results to the piodiu is liioi.'::hi In inpatients. especially cuttnig « ils, u;| S w i s
as
/r/i i/ic
us is
""ny
S M os
.'grce
lined
as
:om<c a I
bit.
;si
s.
iwer
1 to
I. v h
and
d
'ai: d
m-
Ihe following special ttfsi senes is proposed
loi metallurgy workers in .Spain:
hen/isotlna/olone
0. I ' > aq.
h c \ a h \ d t o 1.3.5.(2Indtoxyethyl) 5 tria/inc
I ' aq,
BIM4X7 nitrobutylmorpholine
1',' o.o,
soap alkanolaminc
Occupational
dei ni.it it is constitutes
occupational
sickness
accidents.
In
I9K0.
loi
deiinaiiiis
leave
"Nr i <•(
HOMM-IMUS
konshtuud
In the métallurgie industry, with X 1.31 • « >t ihe
declared occupational illnesses, n occupies the
lirst place.
«
III','
o.i.
lie x v leneglyci'l
'
|(i1 ; aq.
li ielhaiu»lamme
'
s l M t | jo ; ai|.
pel roleum tuiionate
'
I N '.
h should he icxisid pci i<'du .i!l\ .•
;di:i
indasirial de\clopmeuls
References
! Vh^.tll'l /'c/r./'ff/» !i'->i>! , ;t'm • i I s ('ii!'!
H. if:'i .V. r I "4 I
i
5
» M s I V H Î I . I I I Î I S troisi k iiuiiii. .'ILX
a'l.t .li,k ». iru - i iu I,it!11'e êiili'i .u M ' I \f f I >44
i •»u- L^F.
^V Ii W.I 11/ | . | uli;I.IM .1 & iliniirivili.i.n | > Ii tniJ •
ti\ ••••>• , uhium "»/. (;«, np,i.b-<i.il !•••.,•
:ht'
!
7
l
-
ii' vdilion I'luiailclphu I e.i \ I eMieer.
; ; s . itj
Mo«l^^»N(i. I'eirtilouin .«IU.OI.I
IUIMK
x; f"'u, -f.<\p
J' :.:;«.
vm
U'.ts h.:n\
Ke\ M M el a! C'littnie a:ul e-uuline tluids and
I'H-n Nc 1 lev Is n,i : iu* -sk i il. t/»i fr,/H\.« | w, /
i ; : >->
• Noi.il k \ Cunmy tluiJs .nul |i»e skin. ( ui:\
10','> - i 4 1- !4
» 'V'LLNI
11
\
IN
.I
J I I IN.-1 U I> ; ;
ami.U • in, i up \ fi-j lUMi- / ;
, NI : II. E
. •• I
i:\.|i |
* Mi-,les,ai u t. iitaiu iMis ha/ards ,»i îi.'tk'mt>
/'l./lo/'f.;/
iU- 4|-4l«.
» rellin cr
Culling IlimK .md skin .IimiuIois
hi.linnuil \/,-,l 19711- ..'0 Vs-40.
Conclusions
51.2','? o| o c c u p a t i o n a l illnesses in S p a m .
ad our
Cutting tluids and their impurities are principally responsible: positive patch test results in
4".S''i ol patients demonstrate a high
of
sensitizations, besides their irmaricv due to
alkalinity t p l l
These lluids .ne .ilwavs tc.K-i
i
dilution adequate for use. In ^mie ^ a - ^ . ;he
dilution was Ml',/ in w : icr. 11;-. 'i:iu.l\' •
positive r eaclions i> vei v sigi..î u m .is t • >iii •
were carticd out in praiiicallx afl ca < s. -a hn It
atfi'med the sensui/atiou.
I his opinion does not coincide '.villi ii.,ii .il
Hycroft (15) who iccommemls icsiini.1 u n h ihe
undi lilted product toavoid lalse n q M i i w icstilis.
however, we believe it prclerahlc to Ivein wuli
the oil diluted and the oil scries. II mcaiive. ;<
patch test read at 24 h with the undiluted
product could be useful.
With regard to pure mincial oiN. h j advisable to dilute them to 50' ; m o h \ e mi .,ud. it
the p.ilch test is iri ila nti\ c. to u v to dctci mine
die content o! arom.it ic « >mpi m u n i he h uc
drawing a conclusion.
I."
in s.uiti;/ M II I !ftt t m ntctahyxl ;n\-th>:il\ mi 'ht
- ••'/ 11 • Iniiial paper. I y 4
I I I |udes..ii c.. I e/e;uas .is«...».;.:icd u'tii
a-ui inn'I •>» « •» k u « e linuU /'- ••>!,!!. •/..;•; Hi-, •<.'
I'»
I.'
Dii.ilvr II 15
I Î S I K I A A. \lleffc!K L.'LLL.NL LK-MLL.ILLL-s .'J the
ii.imîs due !•« iudiistri.il oi!s .m,l tl;n,|s r ;,i;\
l>'') \t Ml->j;
\v\o
Al OMAK. < <>M)| SVI \/-\R AND ROM AC.Il K \
13*
IV 1'avlor .1 S. Dermatoses associated »uh metal- 25. Angelim Ci. Mcncghmi C I. Dfrmatihs in
working IIuuIn. /V«u«ri//»ic «/ . W Inn-t national cnviint'ci •» vine 7lo i nlhetie too I.mis. C'-niait
ihmiuiiii*
i^" ::I >-::I>.
( i«»i/i••••»< r on Itil'ih iinnn. (Viituvo. II /"/»'« u iirt
h
hlMltUIC IV~'>.
26. Mannuk-ela M. Kou^a M. Pirila V. \llcrc> to
14. I adupelle I M. I e* complications un.niées actngrciiu'im ol sehitle'». Cnntaa l>cr'natiti\ l^"*^:
tuelles liées a l'emploi des huiles indu-aiiellcv
IH5-UI».
\tntri H\r PMO: SS- 1 W- H»H *
:?. Kvc/kcs K. Hr.i»n PM. Hexah>Uro. l.3.5.tnsO-
Sulublt- "»/ <n ./ "u/wi . o t h\Jroxveth>h tru/inc. a new bactcnocidal aç-*ni
,i> a cause ol allergie contact dcrmatmv C ••th/c i
>>f «»//"//'""..7 i/i /m.ittit* I licsi- I «meisity ol
n,-rmann\
2:
C/amhiidge. I47S
U». ( 'alnan CD /I.//';,//.,in.hn,!i\-'i \ I iin ,m,l 2K. Ihorth N. ! he hioeide Grot.in. (>••;!,u t l>cr'w
titi\
2*6.
I \i',r I'cini'if/
l-l*
Markc H P I he -en-iti/ing vltV»t ol preverv.tio.^s
1 " C.im.ll.r:» I M I :i-I •'pidetllloloilii ,i! -Mid) .>1
I'HH.ul i K'l lli.l1 It in :'i N'iiil I « •'./ /V'"ii/f"- lor eoolanlv. (<•»»/./</ />••'"»./'///* i w " 1*l-52
Darngra'ML M (' et .,! l'N IE^IRÎ-.k I.I I ! P"'ir
vrnnt • /'•• ' N '7
v i p p l S< » r
lluidcs d'liMi'.i^i. I ..'/.t'M ./, •!•>!, . ./•-i
rv
I'V Riiil/k: I ittwia f .
V Ntl.nipt -it
15. R v c n l i
R
.in1 . n
im'.isi i.i! ..||s u »i
/<,».•;'-
(ISRS
!"**
'*
M Hoeil-IYlei-i. a ' i:vt|iieiKN o! vi, MMtiMl> to
./> '
.i I'' * ' HI]'
/>«""<»'
[•> S.iiiut/ M ! I, k. w S \ Nkin I. ./.ii.K t:om nu Wl (iiol.ui UK i'i l>eii'M,i:k
I ; * * ' \ "i !
.nul i i. :mi:1 in
in .r- ••
n .1 \ ut :M.g
Rvk.:.
i-1 iifi.m UK a «.oniaei «if.-iti/i-r ' Hr '
"•I .I|ui iii"! - : ••nhi. i
»
In I ..i., i . .-i
( 11 • . u "nil,
K \iin U I tinl-l Jl
1
ill oi.l i.W' MI
!!.;.,'. • -I .( : i',1,,
h»"4 ,.
1
i v'l .i!.
/),»;»,- .'•»-*
'i î I'.-ii'..,
• -ill- Us
vt k*». I it ( io'i.iit M k in
.ocil * 111 ' i ; i ilie e::.r.'.i pie ' •••••' lh '»uii:tn !Ts J.
i.i H...^
Ii W \:.i ::n..roh>,il .lévite I'.r
is »
I ' oui ».>hlhle K,VV
IU FVI-E T'.M'.U ' t >' < ur •/'•/
I»
I ( . I : I II ( ;u. •••• lU' ir UiliN
oil i -i.i- I {*••
!•' J.
,v i m
.'. '-ii .. .<i i . i »is! .!; i • et v.ii
!
m »it -»..i',iii hom 'i.a.l metal a' ' «
» -11 ' 111 • Mads. i • 'I'd : / > > ' / » • , • il')•\iijre>*.'
; i^
2 » M:i«:miNNon M. Kh.nnai: V I he idem<hc.iii> 11 ol
eontai I .dlcrgei><
h\ .nnni.il .i>s.i\ I lie (HI mum Ih-pannwni •<! /•< • '•\:i<-!->\.'\
Jlf\prta/ ./»• /.I
1 l rt It . Suént l':tu
pi a m;, M in i/a1 ion le a V /»MTW / V ' »MJ;></ I
4V. .t'li.imo \t.: ( h.<< I. *
flarct-loir,/
24. ( lonin I . ( i'iiiii, t lU niiiimii. 1 Jinhnruh
Spjin
( liiuehill I iviMj'sioiic. I*>>:0: S4»»
lh'.
7 h2« •
luu
u;i!
plk
.«•Ii
lu n
al-. •
24
fréquence excessive d'affections broncho-pulmonaires variées, l ' S ge> le sexe, la durée d'exposition et la consommation de tabac é.tànt contrôlés.
A notre connaissance, aucune étude récente n'est
venue confirmer des constatations s i m i l a i r e s .
L'inhalation d'huile minérale sous forme de particules de moins de
5 microns pourrait provoquer des réactions fibrotiques dans le tissu
pulmonaire.
Très rarement la réaction est intense et entraîne la
formation de nodules fermes contenant des globules d'huiles.
Ces
lésions excessivement rares sont connues sous l è nom de parafinome.
Des cas de fibrose diffuse et de pneumonie graisseuse ont également
été rapportés chez des t r a v a i l l e u r s exposés a des brouillards d'huiles.
La r e l a t i o n entre ces pathologies et l'exposition aux b r o u i l -
lards d'huiles demeure cependant â être confirmée.
En e f f e t , plusieurs
études épidémiologiques n'ont pas démontré que les brouillards
^hui-
les entraînaient des altérations de la santé des t r a v a i l l e u r s .
_ Effets spécifiques de certains contaminants présents dans les
fluides de coupe
4 . 3 . 1 - Les hydrocarbures_po] > yc^c] > igues_aroma
Les huiles anthracéniques (extraites de la houille par d i s t i l l a t i o n ) ,
qui furent u t i l i s é e s pendant la période d'après guerre, contiennent
des dérivés polycycliques aromatiques.
Le contact cutané prolongé
. avec ces produits peut causer le cancer de la peau.
Ces huiles ne sont plus utilisées de nos jours, mais on peut retrouver de faibles quantités d'hydrocarbures polycycliques aromatiques
(H.P.A.) dans les huiles d'origine p é t r o l i è r e .
On a noté également
un enrichissement en H.P.A. des huiles usagées qui peut être dO â
des réactions de polycondensation aromatique par élévation de
température.
Le-benzo-a-pyrène est parmi tous les H.P.A., la substance comportant l e plus de potentiel cancérogône.
On e f f e c t u e i dans certaines compagnies p é t r o l i è r e s , des extractions
dans le but de réduire considérablement l e contenu en H.P.A. des
huiles qui servent pour l'usinage.
L'hydrogénation catalytique
est également u t i l i s é e pour réduire ce contenu.
I
25
4.3.2 - La N-nitrosodiéthanolamine (NDELA)
L ' u t i l i s a t i o n de n i t r i t e de sodium comme additif a n t i r o u i l l e dans
les huiles synthétiques entraîne la formation de N-nitrosodiéthanolamine (NDELA) en quantité significative (jusqu'à 3%).* 3 7 )
(38)
Le NDELA est une substance cancérogêne chez l'animal.
La pres-
sion de vapeur du NDELA est plutôt f a i b l e , mais les températures élevées produites au niveau de la pièce métallique lors des opérations
d'usinage pourraient entraîner un risque d'inhalation indépendamment
de la formation de brouillard par projection de f l u i d e .
La présence
de brouillards et le contact cutané avec les fluides(37)
créent également un risque d'ingestion et d'absorption cutanée.
Le National I n s t i t u t e for Occupationnal Safety and Health (NIOSH)
a effectué plusieurs études environnementales afin de mesurer le
NDELA dans l ' a i r lors des opérations d'usinage.
Ces études n'ont
pas révélées la présence de NDELA'en quantité respirable.
L'échan-
tillonnage a par contre indiqué la possibilité que la projection de
fluide lors des opérations d'usinage entraînent une contamination
(37)
(de l ' a i r et des surfaces).
I l sera évidemment d i f f i c i l e de démontrer une relation entre le
NDELA et un excès de cancer chez les travailleurs qui u t i l i s e n t des
fluides de coupe puisque ceux-ci contiennent de nombreux produits
dont certains ont également un potentiel cancérogêne ( i . e . les
H.P.A.).< 3 7 >
4.3.3 - Les_additifsJ^extrêmejjression
Les additifs d'extrême pression les plus couramment u t i l i s é s lors
de l'usinage sont:
le phosphate de t r i c r é s y l e , les huiles minéra-
les sulfurées, les savons de plomb (naphténates), les dithiophosphates de zinc ainsi que les parafines, naphtènes et diphényles
chlorés.
\ V l
26
Le premier composé comporte des risques d'intoxication;
quant aux
d1phényles et naphtalènes chlorés, i l s peuvent causer l'acné chlorique.
Les sels de plonfc sont, bien entendu, des composés toxiques.
4.3.4 - Lesjmulsi fiants
Les émul si fiants sont des substances qui f a c i l i t e n t la formation
de Témulslon et qui assure sa s t a b i l i t é .
Le sulfonate de sodium, le naphtênate ou réslnate de potassium ou,
dans certains cas, l ' o l é a t e et le naphtênate de trléthanolamine
sont utilisés comme émulsifiants.
Parmi ces composés, le naphtênate de triéthanolamine est considéré
comme un agent responsable d'allergie cutanée
4.3.5 - Les_baçtériçides
Les bactéricides sont utilisés pour éliminer les bactéries qui prol i f è r e n t dans les liquides de refroidissement.
Habituellement, le$ composés suivants sont u t i l i s é s :
l'acide cré-
syllique, 1'ortho-phénylphénol, le t r i s (hydro^yméthyl) nitrométhane, le chrorophénolate de sodium, les dérivés d'anmonium quaternaires.
Parmi ces composés certains dérivés de la triazine ont été reconnus
comme ailergênes
4.3.6 - Les_baçtéries
La plupart des bactéries que l'on retrouve dans les fluides de
coupe ne contribuent pas toujours â des problêmes de dermatites
de contact.
Plus même, suite â une étude
, on n'a pas pu démontrer l'hypo-
thèse que les bactéries puissent contribuer directement aux dermatltes.
On n'a pas réussi non plus d identifier clairement la présence de
bactéries pathogênes dans les fluides de coupe â cause de la présence trop grande des autres types de bactéries
Par contre, l ' a c t i v i t é métabolique considérable des microorganismes qui se développent dans les fluides de coupe nous amène & supposer que, théoriquement, ces produits métaboliques peuvent agir
comme irritants primaires et sensibilisateurs et que les bactéries,
de façon indirecte, contribuent â la dermatite.
4.3.7 - Lçs_anti : oxydants
Les anti-oxydants ou anti-corrosifs ont pour fonction de protéger le métal fraîchement usiné de la corrosion.
Les principaux produits utilisés S cet effet sont:
les oléates,
naphténates ou stéarates d'amines aliphatiques ou.de morpholine, l'hydroxylamine et le mercaptobenzothiazolate de sodium!6^
Parmi ces composés, on a remarqué que le mercaptobenzothiazolate
de sodium peut produire des réactions cutanées allergiques
4.3.8 - Les_autres_additifs
Parmi les autres additifs, on note les colorants et les antimousses contre le silicone, ainsi que des agents de conditionnement de
Veau tel les polyphosphates, le phosphate trisodique, le borax
et le carbonate de sodium.
Ces produits sont peu ou pas reliés l des affections de la peau
ou â des maladies professionnelles.
36
riFMENTS D'UN PROGRAMME DE SURVEILLANCE DE L'ENVIRONNEMENT
L'Inhalation de brouillards de fluides de coupe et les contacts cutanés prolongés avec ces produits sont les principaux risques a la
santé qui doivent faire l'objet d'une surveillance environnementale
dans les ateliers d'usinage.
6.1 - Determination de la composition des fluides de coupe
Comme les f l u i d e s de coupe sont des produits dont l a composit i o n e s t complexe e t comme c e r t a i n s e f f e t s sur l a santé peuvent
ê t r e r e l i é s 3 un élément c o n s t i t u a n t s p é c i f i q u e , i l importe
avant t o u t de déterminer la composition chimique des produits
utilisés.
Cette première étape de l ' é v a l u a t i o n d e v r a i t per-
mettre de c l a s s e r ces produits dans les grandes catégories de
f l u i d e s de coupe e t d ' i d e n t i f i e r ceux qui sont s u s c e p t i b l e s
de contenir des substances particulièrement dangereuses ( i . e .
hydrocarbures polycycliques aromatiques e t nitrosamines).
Comme nous l'avons mentionné antérieurement, l e Centre de t o xicologie du Québec, le r é p e r t o i r e toxico"logique de la C.S.S.T.
e t la banque de données sur les f l u i d e s de coupe que l ' I . R . S . S . T .
e s t en t r a i n de mettre sur pied sont les p r i n c i p a l e s sources
d'information concernant la composition des f l u i d e s de coupe.
6 . 2 - Evaluation des b r o u i l l a r d s d ' h u i l e
Les b r o u i l l a r d s d ' h u i l e sont formés de f i n e s g o u t t e l e t t e s d ' h u i l e
en suspension dans l ' a i r .
Les principaux modes de génération de b r o u i l l a r d s d ' h u i l e sont:
1°
la l u b r i f i c a t i o n i n t e n t i o n n e l l e de la pièce par atomisation
2°
la force c e n t r i f u g e associée aux hautes v i t e s s e s de r o t a t i o n
de l ' o u t i l ou de la pièce usinée
f
3°
la vaporisation de l ' h u i l e par la chaleur de f r i c t i o n générée
au point de contact o u t i l - p i è c e e t sa condensation subséquente
37
4° la vaporisation et la condensation de l ' h u i l e produite
lorsque des copeaux de métal chauds sont projetés dans
l e retour du f l u i d e de refroidissement.
La concentration de brouillards d ' h u i l e dans un a t e l i e r dépend
du degré d ' e f f i c a c i t é du système de captation u t i l i s é , du type
d ' a l l i a g e usiné et de la sorte de machine u t i l i s é e .
L'expérience acquise dans l e cadre du p r o j e t - p i l o t e en santé
et s é c u r i t é du t r a v a i l dans le secteur de f a b r i c a t i o n des produits en métal ^ s u g g è r e que les niveaux d'exposition aux brouillards d ' h u i l e sont de beaucoup i n f é r i e u r s â la norme de 5 mg/m3
lorsque ces brouillards ne sont pas décelables visuellement. Il
s ' e n s u i t que dans la plupart dès cas, un évaluation q u a l i t a t i v e
v i s u e l l e devrait ê t r e s u f f i s a n t e pour déterminer s ' i l y a un r i s que s i g n i f i c a t i f d'exposition aux brouillards d ' h u i l e et s ' i l e s t
nécessaire de procéder à une évaluation q u a n t i t a t i v e . Dans certains cas oû les g o u t t e l e t t e s sont particuliêrement f i n e s ( i . e .
1 â 4 um) ce principe pourrait ne pas s ' a p p l i q u e r . La présence
d ' h u i l e sur les surfaces (murs, tables de t r a v a i l , planchers, e t c . . . ) ,
peut également indiquer que des brouillards peuvent ê t r e générés
par le procédé.
Lorsqu'il e s t nécessaire de procéder â une évaluation quantitative
un premier échantillonnage en poste f i x e près de la source d'émission pourrait permettre de confirmer ou d ' i n f i r m e r la présence
d'un risque et de mieux cerner la population de t r a v a i l l e u r s qui
devrait f a i r e l ' o b j e t d'un échantillonnage personnel. L'échantillonnage en poste f i x e peut également s e r v i r a v é r i f i e r l ' e f f i c a c i t é
des systèmes de captation a la source déjà en place.
L'évaluation q u a l i t a t i v e ( i . e . visuelle) et l'échantillonnage
en poste f i x e (au besoin) devraient permettre d ' i d e n t i f i e r les
postes de t r a v a i l â risque. Le nombre de t r a v a i l l e u r s a échant i l l o n n e r ainsi que le nombre d'échantillons â prélever et la
38
durée de ces échantillons varieront d'une s i t u a t i o n a l ' a u t r e
dépendant des conditions d'exposition. L ' o b j e c t i f poursuivi,
a savoir la détermination la plus précise possible de la dose
d'exposition, d o i t , dans chacune de ces s i t u a t i o n s , ê t r e conc i l i e r avec les contraintes techniques et économiques.
Les méthodes d'échantillonnage pour les brouillards d ' h u i l e ,
l e s huiles minérales solubles e t le solvant stoddard u t i l i s é
dans certaines opérations de meulage (honing machine) apparaissant a 1'annexe 1.
- Evaluation des risques de contact cutané
Les brouillards d ' h u i l e exposent les t r a v a i l l e u r s non seulement
aux risques r e l i é s â l ' i n h a l a t i o n des huiles et fluides de coupe
mais également au risque de contact cutané " i n d i r e c t " avec des
produits. Par contre, le contact cutané d i r e c t e s t de. loin la
forme la plus fréquente d'exposition des t r a v a i l l e u r s aux f l u i . des de coupe. La manutention de pièces de métal recouverte
d ' h u i l e , l ' o p é r a t i o n et l ' e n t r e t i e n des machines sont autant de
tSches qui entraînent des contacts d i r e c t s . L ' u t i l i s a t i o n de
chiffons imbibés d ' h u i l e et le port de vêtements s o u i l l é s ( i . e .
lorsque les t r a v a i l l e u r s essuient leurs mains sur leurs vêtements ou encore l o r s q u ' i l s conservent des chiffons imbibés dans
leurs poches) sont également des sources de contamination cutanée.
L'évaluation du risque de contact cutané se f a i t évidemment par
l'observation de la s i t u a t i o n de t r a v a i l et la c o l l e c t e d ' I n formation concernant les habitudes de t r a v a i l et d'hygiène personnelle des t r a v a i l l e u r s ainsi que les mesures d'hygiène mises
5 leur disposition (lavabos, douches, v e s t i a i r e s , vêtement de
travail, etc...).
I
39
vL-e»
F
6.4 - Mesures de prévention
F
Plusieurs moyens peuvent ê t r e u t i l i s é s pour prévenir l'exposition
i
f>
I,"
aux fluides de coupe (39):
1 - Le contrôle a la source
C'est de loin le moyen de contrôle le plus e f f i c a c e ;
i l comprend,
entre a u t r e s , les systèmes de ventilation locale e t l e s écrans
1
antiprojection des machines-outils.
R
2 - La s u b s t i t u t i o n
h
r. \
^
Les f l u i d e s de coupe qui contiennent des proportions s l g n i f i c a t i ves d'hydrocarbures polycycllques aromatiques, de nltrosamines
ou d'éléments pouvant e n t r a î n e r la formation de nltrosamines
(amines
et n i t r i t e s ) devraient, dans la mesure du p o s s i b l e , f a i *
re l ' o b j e t d'une s u b s t i t u t i o n . Par contre, comme les f l u i d e s
de coupe sont des produits dont la composition e s t souvent complexe et comme plusieurs des éléments constituants de ces f l u i des n'ont pas f a i t l ' o b j e t d'une évaluation toxicologique complèt e , cette s u b s t i t u t i o n devrait ê t r e f a i t e avec prudence et seulement après une évaluation la plus complète possible des risques
associés au produit de substitution envisagé.
3 - Les équipements de protection r e s p i r a t o i r e individuels
Les équipements de protection r e s p i r a t o i r e individuels devraient
[>,
Être u t i l i s é s seulement comne moyen de contrôle Intérimaire en
attendant la mise en place de mesure de contrôle l la source, ou
p-
l o r s q u ' i l y a une s i t u a t i o n d'urgence ou une exposition occasionnelle.
Lorsqu'il y a une exposition s i g n i f i c a t i v e S un
f l u i d e contenant des substances cancérogènes, les équipements
de protection r e s p i r a t o i r e s de grande e f f i c a c i t é doivent ê t r e
u t i l i s é s pour o f f r i r une protection adéquate en attendant le remb
£
t
placement du f l u i d e de coupe.
40
4 - Les vêtements protecteurs
Des vêtements imperméables devraient ê t r e u t i l i s é s dans la mesure du possible.
Dans tous les cas, les vêtements de t r a v a i l
devraient ê t r e bien entretenus e t changés fréquemment.
Les
responsables de l ' e n t r e t i e n devraient ê t r e informés du risque
de contact avec les f l u i d e s de coupe l o r s q u ' i l s manipulent les
vêtements s o u i l l é s .
5 - L'hygiène personnelle
Toutes l e s surfaces cutanées exposées ainsi que les surfaces en
contact avec des vêtements souillées devraient ê t r e lavées avec
du savon ou un détergent doux. Les t r a v a i l l e u r s exposés devraient
avoir accès 3 des lavabos et des douches bien entretenus.
6 - Isolation des opérations
Les opérations qui génèrent des brouillards devraient, dans la
mesure du possible, ê t r e isolées des autres opérations a f i n de
diminuer l ' e x p o s i t i o n des t r a v a i l l e u r s avoisinants.
7 - Crèmes b a r r i è r e s
Voir à ce s u j e t , l'annexe III
ANNEXE I I I
L'utilisation des crèmes de protection chez les travailleurs exposés
aux fluides de coupe.
L'utilisation des fluides de coupe en milieu Industriel est associé
a un risque de dermatose suite a un contact cutané avec le fluide.
Afin de réduire le risque dé dermatoses professionnelles relié a ces
fluides toute une série de mesures d'hygiène Individuelle et des
locaux doivent être respectées.
Citons:
l'aménagement de déflec-
teurs contre les Ôclaboussures, l'hygiène cutanée et vestimentaire
Incluant un lavage fréquent des mains, le changement et le nettoyage
fréquents des vêtements de travail lorsque souillés et des douches
quotidiennes.
L'utilisation d'une crème de protection pourrait s'avérer utile
lorsque malgré diverses mesures d'hygiène et autres le travailleur
présente un problème de dermatose.
Toutefois, compte tenu des
limites des crèmes de protection, i l serait présomptueux d'en recormiander d'emblée l'usage chez tous les travailleurs exposés aux
fluides de coupe.
En effet, ces dernières présentent un certain
nombre d'inconvénients:
- elles peuvent être elles-mêmes allerqisantes et ne permettent
pas de prévenir les réactions allergiques
- elles n'assurent pas une protection efficace contre 1'exacerbation
des dermatoses par différents moyens mécaniques telles frictions,
égratignures, coupures
- elles peuvent causer une irritation cutanée chez l'usager
- elles peuvent gêner le travail en laissant des marques d i f f i c i l e s
a enlever sur les surfaces travaillées
- elles ne fournissent pas une protection adéquate lorsque les mains
sont Immergées fréquenvnent dans des solvants ou des produits a base
d'huile.
- elles nécessitent des applications fréquentes avec un bon nettoyage
préalable et ne devraient être appliquées que sur une peau saine
exempte de'boutons1, eczéma, écorchures.
Néanmois, elles constituent parfois le seul moyen disponible pour
aider a protéger le travailleur particulièrement a risque de développer une dermatose chez qui des mesures d'hygiène s'avèrent Insuffisantes et le port de gants Impossible.
En effet quoique les
gants procurent une protection plus efficace, i l s ne sont pas toujours acceptés car I l s entraînent une gêne dans la préhension et
la manipulation de petites pièces.
De nlus, fragiles aux petites
déchirures, les gants permettent ainsi l'introduction du produit
nocif et réalisent un contact intime de celui-ci avec les mains.
Hygiène personnelle
L ' u t i l i s a t i o n de savons doux aussi peu agressifs que possible est
a préconiser pour le lavage des mains et autres parties du corps.
Les pates abrasives et les solvants sont a proscrire car 11s
accroissent le risque de dermatoses en détruisant la barrière
cutanée et en Irritant la peau.
De plus, i l est important d'es-
suyer les mains avec des chiffons a usage unique et non pas avec
les chiffons des machines.
Choix d'une crème de protection
Les fluides de coupe se divisent en 3 groupes:
1) les huiles de coupe Insolubles, (60 - 100% d'huile)
2) les huiles de coupe solubles, (5 - 10% d'huile)
3) les fluides de refroidissement synthétiques
(ne contiennent pas d'huile).
Afin d'être efficace une crème de protection doit présenter la
caractéristique suivante:
- être Insoluble dans le produit toxique manipulé afin d'éliminer
autant que possible les risques de contact direct entre la oeau
et la substance toxique.
Ainsi une crème soluble dans l'eau protège contre les huiles,.les
graisses et divers solvants organiques alors qu'une crème hydrofuge
(insoluble dans l'eau) ne protège pas contre ces derniers mais
protège contre les acides et les bases diluées, les savons et les
résinés synthétiques.
A la lueur de ces connaissances, 11 apparaît qu'une crème soluble
dans l'eau a i t une conposltion adéquate pour protéger contre les
huiles de coupe Insolubles.
Un exenple de crème hydrosoluble est
la crème PLY#2 dont la conposltion est la suivante:
eau 74.2%,
bentonite .014%, flocons de savon 11.4%, duponol .003%, farine
d'avoine .003%, methylparaben .002%, acide stéarique .05%,
trlethanolamine .024%.
Par contre, une crème hydrofuge serait
Indiquée pour protéger contre les huiles de coupe solubles ou les
fluides de refroidissement synthétiques.
Un exemple de crème
Hposoluble est la "Crème Barrière" â base de 20% de polyslloxane
diméthylique.
Soulignons que d'autres crèmes commerciales de conposition adéquate
seraient tout aussi efficaces.
Mentionnons la crème Kerodex 51 qui
protège la peau contre les Irritants «nsolubles dans l'eau telles les
-huiles de coupe Insolubles et la crème Kerodex 71 laquelle protège
contre les fluides de coupe solubles et les fluides de refroidissement
synthétiques.
(Kerodex, Ayerst).
Mode d'application
Les crèmes de protection ne procurent qu'une protection partielle et
limitée dans le tenps et doivent donc être appliquées plusieurs fois
par jour.
I l est reconmandé de les appliquer au début du travail et
de les réappliquer l toute reprise du travail ainsi que de bien se
laver les mains avant chaque repas.
Afin de f a c i l i t e r une meilleure
pénétration des crèmes dans la peau, i l convient de nettoyer celleci & fond et de la sécher avant chaque application.
L'application
doit se faire sur la peau et dans le l i t des ongles.
Mentionnons finalement, que les crèmes de protection échouent 'hez
les personnes qui transpirent beaucoup des mains et qu'elles demeurent moins efficaces que les gants, ces derniers procurant une
protection 9 peu près totale.
NOTE
LES CREMES BARRIERES UTILISEES NE DEVRAIENT PAS CONTENIR D'AMINES
SECONDAIRES OU-TERTIAIRES QUI POURRAIENT REAGIR AVEC DES NITRITES
POUR FORMER DES NITROSAMINES.
There is little doubt that workers need to familiarise
themselves with these and other types of misl removal equipment and demand their installation in
their own work-place. The managing director of one
firm manufacturing oil-mist collection units-GKN
Mist Kleen Filter-commented: 'Latterly this unit
has sold successfully in Japan although sales at the
present time are not as successful as wc would hope
for within the UK machining industry.'
Print s h o p mist
removal
Mention has already been made (p.63 ) o"f the health
hazards present in the print shop-and the printing *
companies' lack of interest in their employees' health.
The above surveys indicated that more ink mist was
produced at high production runs (e.g. at 45,000
per hour: 5mg/m 3 ; at 60,000 per hour: llmg/ra 3 )
and the levels varied by a factor of three or more in
different corners of the press room-most probably
due to variations in patterns of air circulation. They
tested three different types of ink-mist suppression
equipment specifically designed for use on newspaper presses. These included two types of electrostatic ink-mist suppressors (with this type the ink
drops are charged with electricity, and are attracted
back onto the ink rollers, which are charged with an
opposite electrical cliarge) and a local exhaust system.
In summary, whatever extraction equipment is used,
it should aim at providing low volume and highvelocity suction as close as possible to the urcc of
emission of oil mist. There is little doubt tliat if
correct advice is taken, and acted upon, adequate
ventillation systems can be installed to remove the
health and safety hazard of oil mist.
Close contact is required between maintenance engineers and unions. The efficiency of ventilation
equipment requires continual monitoring by means
of the levels of oil mist concentration at the outlet.
The results of such monitoring should be used to
check on the efficiency of the equipment.
In practicc, many newspapers were reluctant to
install either of the electrostatic systems because of
the risk of fires in the newsprint caused by the highvoltages present. Therefore the local exhaust system
was tested. In these tests, with 'a more complete
enclosing of the press units', suppression of the ink
mist with the locai exhaust system was 'equal or
better than the results achieved on the same press
units with electrostatic mist suppressors'. The reduction in oil mist concentrations in 'modern highspeed presses . . . in the immediate vicinity of the
press were reduced by approximately 80 per cent'some reduction!
Efficient extraction has
removed all the obvious
oil mist from this gundrilling machine. The
machine operator; Afc
Irene Harrison, thought
the extraction system:
m
,Marvellous, absolutely
brilliant **. And yet no
actual measurements of
the non-visible oil mist
concentration are available; so her lungs may
stiUbeatrisk. It is
obvious her skin still is
ctrisk(FUtermist).
62
Measurements of oil mist concentration taken during
1968-9 in the printing shop of the New York Times
gave results, 'frequently well above the threshold limit
value of 5mg/nW'(the Government's 4safe* level).
Protective clothing
This section has been left to last, because that's
where it belongs. Protective clothing should never
be accepted by workers in response to an industrial
hazard .-except as a temporary measure while the
hazards are removed by some of the methods described above. There is no reason why the workshop
63
O
i
Even soTwe must consider the rights of working
people to protective clothing, since even this most
basic nght is violated.
In addition to the 'baby pants' described above
some workers are supplied with gloves, protectee
aprons etc. A recent survey by Dr Waterhouse and
otneis, of some engineering workers in Birmingham
indicated that far less than half of firms
cannot be as clean and safe as the office-if not the
home. Only pressure from the victims-or potential
victims-of industrial disease will cause this to be so.
As mentioned before, most of the industrial and
Government (not to mention trade union) propaganda relating to health hazards of oil puts great
emphasis on the cleanliness.of the worker. In fact
some of the reports imply that because the Scandinavian incidence of scrotal cancer is much lower than
that in England, this reflects the 'dirty British worker';
no mention is made of the dirty British workshop! It
is only necessary to compare Esso's booklet on the
health hazards of oil with that for Sweden (and
apparently Denmark and Norway) which show
standards of cleanliness in an engineering factory
more like those in an operating theatre than a British
workshop!
In a recent article on the health hazards of oil, Vera
R. Buck, the chief nurse of Rootes Motor Company,
Coventry (now Chrysler), suggested that worker
might wear 'baby pants' instead of protective aprons.
Not only do management want to treat workers like
babies-they now want to dress them like babies too!
The truth about personal hygiene, and its relation to
industrial diseases caused by oil, will be found in
the following recent comment by Dr M.D. Kipling of
Material used:
H.M. Factory Inspectorate:
thin polythene lined
The greatest number of cases (of scrotal cancer)
with stockinette.
occurs among tool and auto setters, a highly
(from: Cutting oil hazards,
paid group of workers with a high standard of
y era R. Buck, 'Occupational
living, among whom lack of cleanliness cannot
Health'. March 1970)
be a major factor.*
64
* Kipling, of t he Factfoiyln fpectorate, believes: "Approximately 1 in 5 of workers
wear some type of protection for their clothing
Why,s t h e figure so low? Well, as indicated above,
lack of supply may w e u be one factor. But of more
importance is the fact that much protective clothing
.s hot to wear, restrictive in use, causes oil to n u T
opto shoes etc-in short they aie bloody uncomfortThere is a great need for some thought and expert
mmt to go into the production of ^ Z i g h t ^
fortable aprons which are porous toTrand n o t ^
s'ows f o r t £ S r t h n d C Z P C n S C e O C S
SsSs^wasr
dry cleaning. These would seem to offer some
advantage over conventional aprons
Masks are sometimes provided for workers in dusty
and oily atmospheres. Since the most dangerous
particles are those below normal vision, to be of any
real effect, such masks would have to be very fine.
Fine masks would usually be very hard to breathe
through. Another approach is to give workers masks
with an independent air line. Although there will be
no trouble m breathing, they are uncomfortable and
leave the wearers isolated. Thus, masks are no
answer to dangerous mist or dust, except for emergency short-time working.
For those majority of workers who rely on ordinary
overalls and swabs, it is important to note that wet
washing is not enough to remove oil contamination
from clothes. Recent scientific tests showed that even
thorough supervised washing removed no more than
half of the original oily contaminants. The table indicates how much oil contaminates cloths, cotton
waste or rags:
Period of time
Barrier creams for use
with m i n e r a l oils
type of oil
Rozalex
No. 2
Nos. 70,73 or
77
No. 11
Nos. 51-55
Straight mineral oib
Bitumen, pitch, etc.
No. 1
No. 12
Per cent weight of oil trapped in cloth
(from: Thit U about health
First day
Second day
Third day
Fourth day
Fifth day
S
12
25
30
40
(from: Oil Dermatitis. NSW Dept. of Health. A ustralia)
The survey by Dr Waterhouse and others, mentioned
above, showed that at least 40 per cent of workers
put oil-soaked swabs into their trouser pocket. This
no doubt contributes to the fact that over half had
oil-stained underpants. Putting oily swabs into your
trouser pocket increases your chances of getting
scrotal cancer.
Only solvent dry cleaning removes oils and abrasives
from overalls and cleaning cloths. Workers must
insist that management supplies regularly dry-clcaned
overalls and cloths, at least twice a week. Pedal bins
should be provided for disposal of oily rags etc. Oily
clothes should be removed immediately after work.
The use of two lockers will ensure that your home
clothes do not get contaminated with oily working
clothes. It is advisable to wear short-sleeved clothing,
since long sleeves tend to get oily at the cuffs, which
rub on the skin and cause it to break into rashes.
Barrier creams are not the cure-all they were once
thought to be. But used properly they may be of
some use. They should be applied before starting
work and each time the hands are washed. It is
important that the right type of cream is used for the
oil you are working with. The table gives some idea
of the types of two reputable barrier creams-Kerodex and R o s a l c x - t o be used with specific oils.
Kerodex
Soluble oils, cutting
emulsions and machine
shop coolants
Sulphurised and
chlorinated straight oils
"
Euo)
Lubricating oth and cutting fluids.
In addition, lanolin-based skin-conditioning creams,
should be applied regularly, to replace Ihe skin's
natural fats removed by the oils.
The Factory Inspectorate in their 1967 annual report
described one firm where 'suds from the workshop
weie piped to the washbasin for use as a skin cleanser,
to help in the removal of neat oil contamination*. This
should never be allowed to happen. When washing or
cleaning the skin the mildest cleaning agents are the
best-lukewarm water and mild white soap. Failing
that, mild skin cleaners (e.g. Rozalex No. 40 or 45,
Kerogel GP) should be used. Rinse waterless cleaners
(e.g. Swarfega) very well or irritating residues can be
left in the skin pores. Never use raw solvents (e g
petrol, paraffin) for cleaning the skin.
Consultation and testing by the shop-floor on cleaning materials and containers should be done in all
works to ensure the best materials are used and that
'contract* materials are not bought for cheapness.
Showers should be taken after work in company time.
The NUM have just negotiated a contract which
includes all cleaning-up and shower time as part of
the paid work. Don't allow this to become unpaid
overtime. Any skin disorders-redness, rashes, itching,
- pain, blisters, blackheads, warts, c u t s boils e t c should receive immediate medical attention.
It will be obvious by now that working people have a
real fight on their hands to obtain a healthy and safe
workplace. The compensation made to casualties in
this industrial war may be seen as the cost of the war.
It is cheaper to pay off the victims than make the
workplace safe and healthy. And anyway, insurance
and law are big business too!
Oêpttmnnp«i San4é çommifnuuvtrv
GtNTRE HOSPUALItft D t VtRu^
4000, b o u l . lasalle.
VERDUN, P. Q?
H4G
XB 87 - 29
(cd.ex.l)
-5SZZ
CHV. DSCV. GAGNON J.
rS 111.r
_
fluides de coupe: guide à 1 'us
j.
,
—— — —
OATE DE RETOUR