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).
Recent failure of Bentley pistons, its potential causes, and next steps for development.
| Identifier | ExFiles\Box 86\2\ scan0046 | |
| Date | 26th August 1933 | |
| X236. To WOR.{Arthur Wormald - General Works Manager} from E.{Mr Elliott - Chief Engineer} E.4/HP.26.8.33. c.c. Hs.{Lord Ernest Hives - Chair} By.{R.W. Bailey - Chief Engineer} Bentley Pistons. With regard to the recent failure of Bentley pistons on Hancock's car, we think this can be explained by the excessive oil and air temperatures encountered and the fact that for some reason the lands between the piston rings had been reduced in diameter and afforded no support for the spring skirt at the high speeds. This is the first time that the skirts have broken from the top end and it is quite possible that had the piston ring lands been bedding at the high speed this breakage would not have occurred. We, therefore, feel that before taking too much notice of this failure we ought to wait the results of running the further pistons which Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} have sent out to replace the broken ones. We are still of the opinion that the skirt with a complete split will never be ultimately satisfactory for high speed work, as expressed in memo E.8/HP.11.5.33, copy of which we attach, and we think something ought to be done along the line of development mentioned in this memo. E.{Mr Elliott - Chief Engineer} | ||