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).
Letter regarding the life, alloy composition, and design improvements of aluminium pistons.
| Identifier | ExFiles\Box 37\3\ scan 095 | |
| Date | 28th February 1918 | |
| X.3177 R2/W28.2.18. 28th February 1918. X. 2638 X. 2749 X. 3177 X. 2892. For the attention of:- The Controller, Technical Dept. Technical Buildings, Embankment. W.C.2 Capt. Briggs. Dear Sir, Re - Aluminium Pistons. With reference to Capt. Briggs' letter regarding the life of aluminium pistons, we have no means of ascertaining the life of these, and the aluminium alloy originally used was not as good a mixture as that which we are at present using. It has been reduced in copper from 12% to 7%, and it is very possible that the earlier pistons will not last as long as those of more recent construction. At the same time we should remember that later deliveries of aluminium ingots do not make such strong alloys owing to the presence of impurities in the ingot metal. This may lead to disastrous results if such impurities increase. We have also added additional webs and generally strengthened the design. In addition to this we would like to point out that the life of the pistons on our engines should not be taken as a criterion as to the life of pistons on other engines, and vice versa, because, we believe, that through Contd. | ||