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).
Unsuitability of an alloy for forged bearing bars due to its low silicon content.
| Identifier | ExFiles\Box 115\1\ scan0294 | |
| Date | 22th February 1937 | |
| 1020 To By/EM. from Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell} c. to HPS.{Horace Percy Smith - Experimental Factory Mgr} Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell}1/AP.22.2.37. R.R.56. Forged Bar for Bearings. In reply to your memo By/EM.7/MN.20.2.37. we do not wish to try any bearings made out of the above alloy, unless approved by the Laboratory. This material should therefore be returned and we are of the opinion that when the replacement bars are ordered, an analysis of the material should be sent by High Duty Alloys in advance of the bars of material. If this conforms to our Laboratory specification, then when the material arrives a further check made by our people before proceeding to produce bearings. The fact that in the existing material, the Silicon content is down giving increased ductility makes us shy of trying this material in view of our previous troubles. Other than for this reason we are trying so many different kinds of bearing alloys that we have not the time nor the units to carry out tests with various forms of RR.56, hence our wish to start off with RR.56. which has a specification to conform with that of which our Laboratory approve. Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell} | ||