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).
Failure of valve springs and seeking clarification on the cause from Mr Royce.
| Identifier | ExFiles\Box 80\3\ scan0205 | |
| Date | 9th July 1915 | |
| C O P Y. x490 COPY. To Wor.{Arthur Wormald - General Works Manager} for EH. from E.{Mr Elliott - Chief Engineer} E1/IB9715. July 9th. 1915. Re Valve Springs. ------------------- A doubtful point has arisen in connection with the use of high or low stresses in valve springs, which we should like you to elucidate. You will remember that we made some thick wire, low stress valve springs for the chassis engine some time ago, but these, when put on test, broke. I understood at the time that they broke owing to the fact that the coils joggled about when the spring was working, although the rocker was following the cam, and that when the springs were taken off and stretched to a greater length for the purpose of increasing the stress, the springs stood and did their work satisfactorily. Mr Royce, however, has the impression that he was told that the breakage of this thick wire spring was entirely due to the jumping of the valve mechanism on the test rig, but these heavy wire springs gave the same load as the thin wire ones, and it would therefore appear that the mechanism should not have jumped. Would you kindly make it clear whether the failure was due to the jellying of the coils, or the jumping of the valve mechanism. E.{Mr Elliott - Chief Engineer} | ||