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).
Main bearing clearance issues due to crankcase distortion and the potential solution of using bell-mouthed bearings.
| Identifier | ExFiles\Box 114\2\ scan0266 | |
| Date | 31th December 1935 | |
| To RHC.{R. H. Coverley - Production Engineer} X1020 Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer}2/KW.31.12.35. Clearance of Main Bearings. We have now established that both on Hall's metal bearings and on lead bronze we require a larger clearance on the mains than on the big ends. Grylls tells us that this is due to distortion of the crankcase, and that the way to overcome the trouble is to make the main bearings slightly bell-mouthed. The suggestion is that white metal bearings, being softer, automatically take up this shape. We would like to find out whether this is so by examining the white metal main bearings on B-9 and B-4-A units which you have at present in the shop. If we can establish exactly what has happened to these main bearings, it might give us a clue as to what shape we ought to make Hall's metal main bearings so that we can run them with white metal clearances. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} | ||