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).
Directive on the required hardness and treatment for components related to ball and roller bearings in gearboxes.
| Identifier | ExFiles\Box 114\2\ scan0019 | |
| Date | 19th February 1934 | |
| X4633 To BY.{R.W. Bailey - Chief Engineer} from HDY.{William Hardy} HDY.{William Hardy}1/MP.19.2.34. C. for. E.{Mr Elliott - Chief Engineer} Hc. [text struck through] Ball and Roller Bearings in Gearboxes. -------------------------- This is to confirm that it is decided that the faces of pieces locating the inner races of bearings shall always be either case hardened or of a hardness not less than 280 Brinell. Washers or distance pieces adjacent to bearings are to be casehardened and ground on both faces. HDY.{William Hardy} | ||