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 Bentley valve spring, concluding a mechanical failure rather than a material fault.
| Identifier | ExFiles\Box 158\4\ scan0128 | |
| Date | 26th February 1937 | |
| 1360 Micro-Examination Report. M.1265. To Rm.{William Robotham - Chief Engineer} Rm{William Robotham - Chief Engineer}/Swdl{Len H. Swindell} HL2/AG.26.2.37. Laboratory. Re: BENTLEY VALVE SPRING. (Your ref: Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell}3/AP.22.2.37.) We have examined this spring in the usual way. The Brinell hardness, grain size and bend, micro-structure etc. are in no way inferior to those of the satisfactory springs previously examined. From past experience we should say that the fracture indicated a mechanical failure rather than any fault in material. Hl. HR | ||