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).
The life of 2¼ inch springs during bumping tests.
| Identifier | ExFiles\Box 119\2\ scan0021 | |
| Date | 29th April 1914 | |
| Wor{Arthur Wormald - General Works Manager}/Mcr4/L29414. April 29th. 1914. LIFE OF PARTS ON BUMPING TESTS. S P R I N G S. 2¼" 3" Humps at 105 revs. per minute. Piece No. | Description. | Time. Hrs. Mins. | Results. | Reference. F2989. | Front Springs 2¼" 900 lbs. 11 plates. | 1 - 40 | Broke at front end near eye. eye unrolling. | Wor{Arthur Wormald - General Works Manager}/Hy{Tom Haldenby - Plant Engineer}7/L311213 F2989. | As above. | 2 - 10 | Broke at front end near eye. eye unrolling. | Wor{Arthur Wormald - General Works Manager}/Hy{Tom Haldenby - Plant Engineer}7/L311213 F2990. | Front Springs 2¼" 950 lbs. | 4 - 15 | Broke at front end near eye. eye unrolling. | Wor{Arthur Wormald - General Works Manager}/Hy{Tom Haldenby - Plant Engineer}7/L311213 Average Life before breaking. F2989 Front Springs 2¼" | 1.hr 55 mins. | average over two. F2990. " " | 4 " 15 " | one. | ||