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).
Micro-examination report on a broken shock absorber lever and shaft made by Gordon Armstrong.
| Identifier | ExFiles\Box 152\1\ scan0212 | |
| Date | 9th December 1936 | |
| 1293 Micro-Examination Report. M1238. To Rm. {William Robotham - Chief Engineer} ~~C. Rm {William Robotham - Chief Engineer} /Les.~~ ~~O.E.~~ HL2/AG.9.12.36. Laboratory. Re: SHOCK ABSORBER MADE BY GORDON ARMSTRONG. We have received from Rm {William Robotham - Chief Engineer} /Les. a main lever from the above containing the end of the shaft, broken in torsion close to the lever. As requested we have examined both lever and the piece of shaft for composition and hardness. ANALYSIS. LEVER. SHAFT. Carbon ... 0.29% 0.31% Manganese ... 0.73% 0.81% These figures lie within the limits of our specification 201D for mild steel for general purposes. Hardness. Lever. surface near shaft fixing - 199 Centre of arm - 224-235 End of Shaft. Centre - 211 Near surface - 218 The splines on the shaft end and the serrations cut in the lever to receive them had not been case-hardened. MICRO-EXAMINATION. It was evident from the structure that the lever (Photomicrograph No. A1541) had been heat-treated, whilst the shaft had not (photomicrograph No. A1542.) contd. | ||