From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Condenser manufacturing issues, specifically the drilling of bolt holes and suggestions for reducing scrap.
| Identifier | ExFiles\Box 34\1\ Scan140 | |
| Date | 20th November 1919 | |
| Contd. -2- EFC3/T20.11.19. Regarding condensers Nos. 4 & 5, No.4 of which was received with no bolt holes, but drilled by us, and No.5 of which was received with bolt holes, both these condensers withstood our tests when outside the cases. Neither condenser has been able to stand the tests when fitted up in case with the bolts in position, and it is fairly obvious on trying these, as I have seen myself, that the breakdown has taken place at the point where the bolt passes through the condenser. It will be remembered that we found it quite necessary ourselves to drill all the holes in the mica previous to assembling. In the case of No.4 the drilling was, of course, done afterwards (by us) and in the case of No.5 also, we should suspect that the drilling was done by the S.E.C. after assembling. It would appear that if the S.E.C. are to make a job of these condensers, it will be necessary to do what we do, namely, drill each sheet separately and use only those micas which have been successfully drilled without any cracks, as you know we still have to scrap a large amount of mica owing to cracks developing round the holes during the drilling. We understand there is still a comparatively large amount of scrap, even in finished condensers, which have well stood the tests, previous to being fitted in cases, and we feel that we could reduce this amount of scrap if we allowed a greater clearance of the tin foil sheets round the holes: As it is now possible to get the necessary capacity with a smaller PROL. P192. M.4491-Wt 28531/D1400. 1000. 11/18 Contd. | ||