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).
Proposing a series of tests on pistons to investigate gudgeon pin distortion, focusing on pin size and piston brinell hardness.
| Identifier | ExFiles\Box 10\1\ 01-page71 | |
| Date | 31th May 1928 | |
| X685 To RHC.{R. H. Coverley - Production Engineer} from Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} Hs{Lord Ernest Hives - Chair}/Rm{William Robotham - Chief Engineer}2/LG31.5.28. PISTONS. X8090 We attach a note from Mx.{John H Maddocks - Chief Proving Officer} on Pistons in which you will see that at the moment they are not having so much trouble with the bedding of the pistons as it comes off the machine as with the gudgeon pin distortion. We think it would be of very great interest to make a series of tests to prove what size of gudgeon pin actually causes distortion i.e., apparently if they are made a push fit at 80°C they do not cause distortion; how much larger can the gudgeon pin be made without causing distortion? The second factor appears to be the piston brinell. The set of sand-cast pistons we have in Halls alloy should have a brinell of about 120°C. One would imagine that the gudgeon pin distortion would be less marked on these pistons and we should like some tests making to prove this point. Having established the gudgeon pin fit necessary to avoid distortion we should like to try a set of pistons so fitted to one of our car engines to see if we run into any gudgeonpin knocks. We should like to know whether you think the practice of fitting the pistons complete with gudgeon pin rod to the cyls. is feasible. As a result of these tests however we hope to be able to say that gudgeon pin distortion can be avoided and so the pistons can be fitted to the cyl. independently. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} | ||