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Photographic dry processing
PHOTOGRAPHIC DRY PROCESSING
A new d r y - p r o c e s s i n g s y s t e m i s under study at the Kodak R e s e a r c h L a b o r a t o r i e s in R o c h e s t e r , New York, USA. The s i l v e r - h a l i d e s y s t e m , still in the e x p e r i m e n t a l stage, i s a d a p table to beth photographic film and p a p e r . A f t e r e x p o s u r e , the i m a g e is m a d e p e r m a n e n t by heating the film or p a p e r to 225-245°C for 2 - 4 s e c , and then made v i s i b l e by o v e r a l l light exposure. The s y s t e m was announced by Dr R o b e r t E. Bacon and Ralph S. Colt (left and r i g h t r e s p e c t i v e l y in F i g 17) of the Kodak R e s e a r c h L a b o r a t o r i e s at a m e e t i n g of the Society of P h o t o graphic S c i e n t i s t s and E n g i n e e r s in Boston. It should find many a p p l i c a t i o n s in r e c o r d i n g data f r o m c o m p u t e r s and o t h e r e l e c t r o n i c d e v i c e s . F i l m and p a p e r can be exposed, for example, with l a s e r b e a m s , e l e c t r o n s in a vacuum, e l e c t r o n i c f l a s h l a m p s , and cathode r a y t u b e s with f i b r e - o p t i c f a c e p l a t e s . The m a t e r i a l s a r e n o r m a l l y s e n s i t i v e to the blueu l t r a v i o l e t r e g i o n of the e l e c t r o m a g n e t i c s p e c t r u m , but v e r s i o n s can be p r e p a r e d that a r e s e n s i t i v e to g r e e n and r e d light.
The n o n - d e s t r u c t i v e t e s t i n g s e c t i o n of the Metallurgy Group at the Station s u p p l i e s s p e c i a l i s t advice and a s s i s t a n c e in r a d i o g r a p h y and magnetic c r a c k detection, and is a l s o involved in the d e v e l o p m e n t of u l t r a s o n i c t e s t i n g for u s e in p i p e l i n e s . In addition, the s e c t i o n s e t s inspection s t a n d a r d s for pipe m a n u f a c t u r e and such a s s o c i a t e d c o m p o n e n t s a s p i g - t r a p s and bends, and m a i n t a i n s a watching b r i e f on the application of t h e s e s t a n d a r d s by the i n s p e c t i o n a u t h o r i t i e s . I n s p e c t o r s e m p l o y e d by agents for the gas industry in s i t e c o n t r a c t s a r e examined. An extensive p r o g r a m m e of d e v e l o p m e n t work planned on a s h o r t t e r m b a s i s is under way in the Welding Section, a s p a r t of a g e n e r a l policy of i m p r o v e m e n t and r e p l a c e m e n t of the welding p r o c e s s e s used in the gas industry.
HIGH-SPEED FACSIMILE DISPLAY OF FLAW SIGNALS
The high-speed facsimile display of flaw signals or metrological readings is used for testing tubes which have fins in their walls. A rectangular format represents a developed plan of the tube, one side of the rectangle representing the length of the tube and the other side its circunfference. The flaws which are detected by ultrasonics would be masked by the signals from the fins if they were not spatially resolved in the display. The equipment overcomes the former limitations of writingspeed on electrosensitive paper and was developed under contract by the University of Salford Department of Electrical Engineering. A system of cathode-ray storage tubes produces a continuous ttvv-type raster display. The continuous revolution of the tube under inspection produces a moving p i c t u r e in which the v i e w - t i m e of any f e a t u r e d e p e n d s on the n u m b e r of l i n e s on the r a s t e r and on the r a t e of scanning of the Lest rig. R e a c t o r Fuel E l e m e n t L a b o r a t o r i e s , Springfields, P r e s t o n , L a n c a s h i r e , England (shown at The Physics Exhibitio~z 1968)
GAS COUNCIL RESEARCH STATION
Sited at Killingworth, n e a r Newcastle, the E n g i n e e r i n g Re ~ s e a r c h Station is the Gas C o u n c i l ' s f i r s t e s t a b l i s h m e n t in a d e v e l o p m e n t a r e a . The a i m s of the Station (Fig 18) a r e twofold; to e n s u r e that the r e s u l t s of r e s e a r c h a r e applied to the gas i n d u s t r y ' s p r o b l e m s through the c l o s e c o - o p e r a t i o n of e n g i n e e r s , m e t a l l u r g i s t s and c h e m i s t s , and to act as an o r g anization that ' t h i n k s ' - - a l a r g e p r o p o r t i o n of the work at the Station i s devoted to t h e o r e t i c a l work, calculations and literature surveys.
THERMOGRAPHY DETECTS INTERNAL CORROSION IN BOILER TUBES
An i n f r a - r e d t e l e v i s i o n c a m e r a is being u s e d by the C e n t r a l E l e c t r i c i t y R e s e a r c h L a b o r a t o r i e s at L e a t h e r h e a d for d e t e c ting the p r e s e n c e of i n t e r n a l c o r r o s i o n in power station b o i l e r tubes. The c o r r o s i o n product, m a g n e t i t e , has a t h e r mal conductivity l o w e r than that of the s u r r o u n d i n g s t e e l , and so a r e a s of c o r r o s i o n r e s u l t in locally r e d u c e d conductance r e l a t i v e to n o r m a l tube--although the wall t h i c k n e s s i s actually r e d u c e d at such points. By e s t a b l i s h i n g heat t r a n s f e r through the tube wall, t h e s e r e g i o n s may be r e v e a l e d by the resulting temperature differences.
non-destructive testing August 1968
275
A new d r y - p r o c e s s i n g s y s t e m i s under study at the Kodak R e s e a r c h L a b o r a t o r i e s in R o c h e s t e r , New York, USA. The s i l v e r - h a l i d e s y s t e m , still in the e x p e r i m e n t a l stage, i s a d a p table to beth photographic film and p a p e r . A f t e r e x p o s u r e , the i m a g e is m a d e p e r m a n e n t by heating the film or p a p e r to 225-245°C for 2 - 4 s e c , and then made v i s i b l e by o v e r a l l light exposure. The s y s t e m was announced by Dr R o b e r t E. Bacon and Ralph S. Colt (left and r i g h t r e s p e c t i v e l y in F i g 17) of the Kodak R e s e a r c h L a b o r a t o r i e s at a m e e t i n g of the Society of P h o t o graphic S c i e n t i s t s and E n g i n e e r s in Boston. It should find many a p p l i c a t i o n s in r e c o r d i n g data f r o m c o m p u t e r s and o t h e r e l e c t r o n i c d e v i c e s . F i l m and p a p e r can be exposed, for example, with l a s e r b e a m s , e l e c t r o n s in a vacuum, e l e c t r o n i c f l a s h l a m p s , and cathode r a y t u b e s with f i b r e - o p t i c f a c e p l a t e s . The m a t e r i a l s a r e n o r m a l l y s e n s i t i v e to the blueu l t r a v i o l e t r e g i o n of the e l e c t r o m a g n e t i c s p e c t r u m , but v e r s i o n s can be p r e p a r e d that a r e s e n s i t i v e to g r e e n and r e d light.
The n o n - d e s t r u c t i v e t e s t i n g s e c t i o n of the Metallurgy Group at the Station s u p p l i e s s p e c i a l i s t advice and a s s i s t a n c e in r a d i o g r a p h y and magnetic c r a c k detection, and is a l s o involved in the d e v e l o p m e n t of u l t r a s o n i c t e s t i n g for u s e in p i p e l i n e s . In addition, the s e c t i o n s e t s inspection s t a n d a r d s for pipe m a n u f a c t u r e and such a s s o c i a t e d c o m p o n e n t s a s p i g - t r a p s and bends, and m a i n t a i n s a watching b r i e f on the application of t h e s e s t a n d a r d s by the i n s p e c t i o n a u t h o r i t i e s . I n s p e c t o r s e m p l o y e d by agents for the gas industry in s i t e c o n t r a c t s a r e examined. An extensive p r o g r a m m e of d e v e l o p m e n t work planned on a s h o r t t e r m b a s i s is under way in the Welding Section, a s p a r t of a g e n e r a l policy of i m p r o v e m e n t and r e p l a c e m e n t of the welding p r o c e s s e s used in the gas industry.
HIGH-SPEED FACSIMILE DISPLAY OF FLAW SIGNALS
The high-speed facsimile display of flaw signals or metrological readings is used for testing tubes which have fins in their walls. A rectangular format represents a developed plan of the tube, one side of the rectangle representing the length of the tube and the other side its circunfference. The flaws which are detected by ultrasonics would be masked by the signals from the fins if they were not spatially resolved in the display. The equipment overcomes the former limitations of writingspeed on electrosensitive paper and was developed under contract by the University of Salford Department of Electrical Engineering. A system of cathode-ray storage tubes produces a continuous ttvv-type raster display. The continuous revolution of the tube under inspection produces a moving p i c t u r e in which the v i e w - t i m e of any f e a t u r e d e p e n d s on the n u m b e r of l i n e s on the r a s t e r and on the r a t e of scanning of the Lest rig. R e a c t o r Fuel E l e m e n t L a b o r a t o r i e s , Springfields, P r e s t o n , L a n c a s h i r e , England (shown at The Physics Exhibitio~z 1968)
GAS COUNCIL RESEARCH STATION
Sited at Killingworth, n e a r Newcastle, the E n g i n e e r i n g Re ~ s e a r c h Station is the Gas C o u n c i l ' s f i r s t e s t a b l i s h m e n t in a d e v e l o p m e n t a r e a . The a i m s of the Station (Fig 18) a r e twofold; to e n s u r e that the r e s u l t s of r e s e a r c h a r e applied to the gas i n d u s t r y ' s p r o b l e m s through the c l o s e c o - o p e r a t i o n of e n g i n e e r s , m e t a l l u r g i s t s and c h e m i s t s , and to act as an o r g anization that ' t h i n k s ' - - a l a r g e p r o p o r t i o n of the work at the Station i s devoted to t h e o r e t i c a l work, calculations and literature surveys.
THERMOGRAPHY DETECTS INTERNAL CORROSION IN BOILER TUBES
An i n f r a - r e d t e l e v i s i o n c a m e r a is being u s e d by the C e n t r a l E l e c t r i c i t y R e s e a r c h L a b o r a t o r i e s at L e a t h e r h e a d for d e t e c ting the p r e s e n c e of i n t e r n a l c o r r o s i o n in power station b o i l e r tubes. The c o r r o s i o n product, m a g n e t i t e , has a t h e r mal conductivity l o w e r than that of the s u r r o u n d i n g s t e e l , and so a r e a s of c o r r o s i o n r e s u l t in locally r e d u c e d conductance r e l a t i v e to n o r m a l tube--although the wall t h i c k n e s s i s actually r e d u c e d at such points. By e s t a b l i s h i n g heat t r a n s f e r through the tube wall, t h e s e r e g i o n s may be r e v e a l e d by the resulting temperature differences.
non-destructive testing August 1968
275