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).
Outlining the design points for experimental exhaust valve seats for a Bentley aluminium cylinder head.
| Identifier | ExFiles\Box 86\1\ scan0033 | |
| Date | 7th November 1933 | |
| To E; from Hs{Lord Ernest Hives - Chair}/CTS.{C. Trot Salt - Carburation} c: to Ey. Hs{Lord Ernest Hives - Chair}/CTS.{C. Trot Salt - Carburation}6/KT.7.11.33. BENTLEY ALUMINIUM CYLINDER HEAD. EXHAUST VALVE SEATS. The attached drawing V.1653 shows an experimental valve seat; dimensions having been compiled from available data from research work carried out on the Kestrel aero engine. Points born in mind were as follows :- (1) Nothing is gained from the point of view of heat flow by altering the width of the seat. (2) The outer rim of the insert should be fairly deep, as maximum strength is needed at this point. (3) The actual machining of the cylinder head should be such as to give approx. .010" clearance on the diameter of the outer rim of the valve seat. Expansion and distortion of the cylinder head does not then convey itself to the valve seat. Heat transmission is not affected by this, as heat will take the line of least resistance to the seating at the base of the thread. (4) If this seat proved efficient, the same valve area is maintained as previously on the castiron cyl. head. Hs{Lord Ernest Hives - Chair}/C. T. Salt. | ||