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).
Minutes from a meeting discussing design specifications for new valve springs to achieve lower maximum stress.
| Identifier | ExFiles\Box 80\3\ scan0093 | |
| Date | 27th December 1911 | |
| Valves and valve springs Contd. (8) particular information should be given to Mr Swet-nam as follows, in order that he might go further into the matter and obtain a spring of lower maximum stress. 1. The diameter of wire used, to be the same as that of the springs at present fitted as standard; this figure to be obtained by actual measurement from several standard springs. 2. The working length of the spring will be increased by 1/4" by means of the special washers already designed and made. 3. The total length of wire used to be such that there will be 12 complete turns (measured to the extreme ends of the wire). The outside diameter of coils to be the same as standard. 4. The load on the spring when in position with the valve shut to be 40 to 42 lbs. The overall length of the spring should be left open for the maker. The Committee further agreed that these particulars should not relieve Mr Swetnam of his responsibility with regard to obtaining a spring of the required design. He should go into the calculations with the aid of this information. Mr Swetnam agreed to do so, and submit the results to the committee. 104th Meeting Dec.27th.11. Re valve springs. Mr Wormald informed the Committee that the testing rig would be finished very shortly. | ||