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 from Ethyl Export Corporation discussing testing methods for valve burning using saw cuts on valve seats.
Identifier | ExFiles\Box 27a\4\ Scan272 | |
Date | 22th November 1933 | |
CABLEGRAMS: ETHYLPORT.LONDON. TELEGRAMS: ETHYLPORT.CHURTON. X1282. ETHYL EXPORT CORPORATION Incorporated in the State of Delaware, U.S.A. with limited liability. ABFORD HOUSE, VICTORIA LONDON, S.W.1 PERSONAL Telephone: VICTORIA 5 5 2 0 Head Office: 135 EAST 42ND STREET NEW YORK, U.S.A 22nd November, 1933. E.{Mr Elliott - Chief Engineer} W. Hives Esq., Rolls Royce Ltd., Nightingale Road, DERBY. Dear Hs.{Lord Ernest Hives - Chair}, After I had seen you the other day and having had time to consider your idea concerning the saw cuts across the seats of the valves which you propose testing in the single cylinder engine, it just occurred to me that this might not quite show up what you require to find out. In other words, "blow-past", which we think starts valve burning, occurs when the valve is off the seat somewhat when it should be closed. It may be away from the seat due to distortion or due to scale, in which case it cannot get rid of any heat at all via the seat insert and it, therefore, runs at a very high temperature. If you saw cut the valve seat, about 99.99% of the valve is still seating properly and therefore the valve temperature will not be seriously raised even locally near the cut. Perhaps, the best way to imitate working conditions might be to put a small spot of Stellite on the valve seat and definitely hold it off. I hope you will accept this for what it is worth, although I still think your valves will start burning at or about the saw cut!!! Kindest regards, Yours sincerely, F.R.Banks FRB/WNT | ||