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).
Letter to a supplier discussing piston ring distortion and the 'bedding in' process for engines.
| Identifier | ExFiles\Box 148\1\ scan0127 | |
| Date | 1st May 1939 | |
| 1256 EXPERIMENTAL DEPARTMENT. Rm{William Robotham - Chief Engineer}/CTS.{C. Trot Salt - Carburation}3/JH. 1st. May, 1939. Wellworthy Piston Rings Ltd., Lymington, HANTS. For the attention of Mr. Blackith. Dear Sirs, A letter from you to our Mr. Clough has been passed to we people of the chassis section to note. This is in connection with the Brinell hardness of piston rings and the reference FB/EHF. dated 5th. April. Some time ago, we wrote to you in connection with the query, to what extent to rings distort when being stretched over the piston, and does this affect the initial bedding of the rings when assembled in the engine. During the initial running of a new engine, we know that the rings go through a period of 'bedding in'. In the case of rings which are free to turn (not pegged) it can be said that an efficient oil seal will not result, until rings and cylinders have worn each other into a more perfect circle. Would it not follow therefore that the more the rings are distorted (as a result of stretching over the piston) the longer will be the period of 'bedding in'. We would appreciate your further opinion on this matter in the light of recent development on the aero side. Yours faithfully, FOR ROLLS-ROYCE LTD. | ||