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).
Design and use of tapered, faked, and lapped piston rings in car and aero engines, particularly regarding oil consumption.
| Identifier | ExFiles\Box 182\M18\ img079 | |
| Date | 12th May 1927 | |
| To Hs.{Lord Ernest Hives - Chair} from R.{Sir Henry Royce} c. to BJ. RG.{Mr Rowledge} c. to BY.{R.W. Bailey - Chief Engineer} E.{Mr Elliott - Chief Engineer} R5/122.5.27. PISTON RINGS. X.2103 X.741 X.2040 X.3998 I understand that we are using on both car and aero engines, piston rings ground to a slight taper on the outside to act as oil scrapers. I do not agree with the use of faked rings, and cannot see that it is likely to lead to any good, except for research work. As regards the car engine, it runs for so small a portion of its time at very high speed that oil consumption ought not to be seriously high from this cause. We should rather expect that over-oiling would be experienced when running slowly with small throttle opening. You have still to report on modifications to the angle of the oil holes - i.e. looking up instead of down, and these also with perfect circle rings. Ring. With and without groove below. During the early days we got good results with lapped rings: these are good because they represent worn rings. R.{Sir Henry Royce} | ||