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).
Proposing solutions to overcome the problem of broken valve springs.
| Identifier | ExFiles\Box 80\3\ scan0113 | |
| Date | 7th March 1912 | |
| Mr Wormald Recd. 11/3/12 Le CanadelHenry Royce's French residence. 7th March.1912. [STAMP: W M MAR 19 13 RECEIVED] [STAMP: C.E. and Technical Committee] Re Valve Springs. The trouble of broken valve springs I propose to attack in three ways, each of which should be sufficient to overcome the difficulty. They are as follows :- 1. Increase diameter of convolutions of the springs. (These I understand the Works have already in hand). There is room for this on all engines made since moving out the valves; - (Mr Platford says commencing 1400) 2. Increase diameter of convolutions of the springs at the top only. Either No. 1 or No. 2 suggestion will allow a slightly larger gauge of wire to be used and so lessen the maximum stress. Increasing the diameter of the convolutions with the same gauge of wire should also reduce the maximum stresses. The object of No. 2 suggestion is to reduce the stress on the bottom convolutions, the weight of the spring itself tending to increase the stress at this point; and it appears that nearly all the springs break at the bottom. | ||