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).
Failures in chassis type condensers due to cracks in mica plates and proposing ordering pre-cut plates for experimentation.
| Identifier | ExFiles\Box 34\1\ Scan071 | |
| Date | 28th July 1919 | |
| To Mr. Coverley. from EFC. X.2512. EFC3/T28.7.19. RE CHASSIS TYPE CONDENSERS. Regarding the question of condensers, we do not seem to be entirely successful with these up to the present. We rather put this down to the fact that the mica is received by us in plates from which we have to do our own cutting and splitting. We are satisfied that every possible care has been taken in your Department with these operations, but we are not certain from inspection of condensers which have broken down on test, that little cracks do not exist in about one or two sheets in each condenser after finally building up, which cracks are the cause of the breakdown. We cannot conceive otherwise than that breakdown actually occurs through the substance of the mica from plate to plate rather than round the edge. We believe it was the original idea in connection with aero condensers, to obtain the mica plates ready cut to shape. We are not aware of the exact reason why this method was departed from, and as Mr. Ormerod is not here to-day, we cannot discover this at the moment. It appears to us that it would be worth while, as a matter of experiment and for the purpose of obtaining knowledge generally on the construction of condensers, to order a number of mica plates, already cut to shape N.786, from a firm experienced in this sort of work. For this purpose we are asking Mr. Mills to order up 1600 mica plates, N.786, from which we can build up, say, half a dozen condensers, and compare these experimentally Contd. | ||