STERN TUBE LUBRICATOR
FIRE-RESISTANT LUBRICANT
S t e r n tube l u b r i c a t i o n on s h i p s i s f r e q u e n t l y o v e r l o o k e d b e c a u s e of i n c o n v e n i e n t s i t i n g of l u b r i c a t o r s in d i r t y and difficult to r e a c h s i t u a t i o n s . A s t e r n tube l u b r i c a t i o n kit (Fig 9) now b e i n g m a n u f a c t u r e d by T e c a l e m i t should e l i m i n a t e t h i s p r o b l e m . T h e kit c o n t a i n s a s c r e w o p e r a t e d p i s t o n l u b r i c a t o r which f e e d s g r e a s e v i a a length of nylon tube to a fitting s c r e w e d into the s t e r n tube b e a r i n g . T h e l u b r i c a t o r c a n be mounted in any c o n v e n i e n t p o s i t i o n and i s m a d e of b r a s s with e x t e r n a l p a r t s c h r o m i u m plated to r e s i s t the m a r i n e e n v i r o n m e n t . T h e need for r e f i l l i n g the r e s e r v o i r with g r e a s e i s i n d i c a t e d by the piston s c r e w p o s i t i o n .
A f i r e - r e s i s t a n t l u b r i c a n t f o r h y d r a u l i c and c o m p r e s s o r a p p l i c a t i o n s is now b e i n g m a r k e t e d by T e x a c o Inc. C a l l e d T e x a c o Safetytex 215, the new p r o d u c t i s a p h o s p h a t e e s t e r m a t e r i a l for u s e w h e r e safety c o n s i d e r a t i o n s d e m a n d a f i r e r e s i s t a n t l u b r i c a n t . T e x a c o say the l u b r i c a n t is f r e e of c h l o r i n e and o t h e r a d d i t i v e s , h a s e x c e l l e n t l u b r i c i t y and low volatility, and is s h e a r s t a b l e .
T e c a l e m i t ( E n g i n e e r i n g ) Ltd, Plymouth, Devon, England
Safetytex 215 is e s p e c i a l l y r e c o m m e n d e d f o r e l e c t r o - h y d r a u lic g o v e r n o r u n i t s u s e d to c o n t r o l speed, load, and s t e a m p r e s s u r e of s t e a m t u r b i n e g e n e r a t o r s that o p e r a t e u n d e r high p r e s s u r e at high t e m p e r a t u r e s . It i s also r e c o m m e n d e d f o r u s e in o t h e r h y d r a u l i c a l l y a c t u a t e d e q u i p m e n t s u c h as die c a s t i n g m a c h i n e s and p r e s s e s w h e r e t h e r e is a high r i s k of h y d r a u l i c oil f i r e s . Texaco Inc, 135 E a s t 42nd Street, New York, NY 10017, USA
AIR BEARING FOR PRECISION SQUARE
In l a r g e s c a l e m e t r o l o g y , the m o v e m e n t of p r e c i s i o n c y l i n d r i c a l s q u a r e s o v e r s u r f a c e t a b l e s p r e s e n t s p r o b l e m s due to t h e i r weight. T h i s difficulty h a s b e e n o v e r c o m e a t the M i n i s t r y of Defence Quality A s s u r a n c e D i r e c t o r a t e (QAD) by a s p e c i a l b a t t e r y d r i v e n a i r b e a r i n g i n c o r p o r a t e d in the cylinder.
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T h e c y l i n d e r (Fig i0") c o n t a i n s a b a t t e r y / m o t o r / c o m p r e s s o r p o w e r p a c k which d i r e c t s a i r into c h a n n e l s in the b a s e of the unit and p r o v i d e s a thin a i r film on which the c y l i n d e r can be floated. The c o m p r e s s o r i s c o n t r o l l e d f r o m a switch on the p i s t o l grip, e x t e r n a l to the c y l i n d e r , thus enabling the o p e r a t o r to c o n t r o l the m o v e m e n t of the c y l i n d e r with a m i n i m u m of effort. An a l t e r n a t i v e s y s t e m u s e s a n a i r supply f r o m an e x t e r n a l s o u r c e , but t h i s i n v o l v e s f l e x i b l e piping a t t a c h e d to the c y l i n d e r . QAD is r e s p o n s i b l e for m e a s u r i n g a r a n g e of l a r g e c o m p o n e n t s and h a s a need for p r e c i s i o n c y l i n d e r s up to 1.2 m (4 ft) high and weighing 76 kg (170 ib). With c y l i n d e r s of t h i s s i z e the c o n v e n i e n c e of the b e a r i n g b e c o m e s a p p a r e n t . T h e Quality A s s u r a n c e D i r e c t o r a t e , F i g h t i n g V e h i c l e s and E n g i n e e r i n g Equipment, (QAD/FVE), Station Approach, Kidbrooke, London SE3
IBatteries
P L U M M E R BLOCKS
A new d e s i g n of p l u m m e r block, d e s i g n a t e d s e r i e s SNA, h a s b e e n i n t r o d u c e d in the UK by Skefko. SNA s e r i e s p l u m m e r b l o c k s a r e d e s i g n e d f o r u s e with s e l f - a l i g n i n g b a l l b e a r i n g s or spherical roller bearings carrying predominantly vertical loads. The new s e r i e s i s a d e v e l o p m e n t of the SN s e r i e s of SKF p l u m m e r b l o c k s . The two s e r i e s have the s a m e b a s i c d i m e n s i o n s and a r e i n t e r c h a n g e a b l e . As the new s e r i e s b e c o m e s p r o g r e s s i v e l y a v a i l a b l e it will c o m p l e t e l y r e p l a c e the old. A f e a t u r e of the new d e s i g n is a m o r e r o b u s t housing which, Skefko claim, is 50 to 100% s t r o n g e r , a c c o r d i n g to size, than the f o r m e r SN housing, with no i n c r e a s e in weight. E l o n g a t e d b o l t h o l e s p e r m i t s l i g h t a d j u s t m e n t in the p o s i t i o n i n g of the p l u m m e r block. C o r r o s i o n r e s i s t a n t s t e e l r i n g and r u b b e r V - r i n g s e a l s a r e fitted as s t a n d a r d , but o t h e r s e a l i n g s y s t e m s can be m a d e a v a i l a b l e f o r s p e c i a l r e q u i r e m e n t s . T h e r e a r e end c o v e r s for housing m o u n t e d at s h a f t ends.
Cy[indergauge Electric motor-~ ~'~"~ ] drivingcompressor~ ~ Concentric[~ groove\ I I Do~iV;r:°sso--~-~I[ I/'xL~L~II ~ g Battery meter c h o ~r g e ~ Bose-~~
SNA s e r i e s p l u m m e r b l o c k s a r e a v a i l a b l e in m e t r i c and inch s i z e s f o r s h a f t s of up to and including 140 m m (51/2 in) d i a meter. Skefko Ball B e a r i n g Company Lid, L e a g r a v e Road, Luton, B e d f o r d s h i r e , England
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~ ~ 10
Viewon undersideof base Air compressor Electricalconnectio+n for rechargingbatteries T R I B O L O G Y M a y 1971
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