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).
Standardisation sheet detailing alterations for the Kestrel G/1 Plunger Blown Piston.
| Identifier | ExFiles\Box 178\4\ img078 | |
| Date | 9th May 1932 | |
| ORIGINAL R.{Sir Henry Royce} From Hs{Lord Ernest Hives - Chair}/LRH. c. to SS.{S. Smith} c. to O'R.{Sir Henry Royce} c. to Rg.{Mr Rowledge} c. to Fl. c. to Dy.{F R Danby} c. to EP.{G. Eric Platford - Chief Quality Engineer} c. to L. X3996. Hs{Lord Ernest Hives - Chair}/LRH.10/HA. 9.5.32. Re: STANDARDISATION SHEET No: KESTREL G/1 PLUNGER BLOWN PISTON 1695. The above standardisation sheet, which has recently been circulated, whilst giving the DES drg No. of the pistons, does not mention specifically the actual alterations from the present standard pistons. The following particulars are attached to make these quite clear. The drawing, D.M.S.1695 makes the following alterations :- (1) Deletes the piston ring stops. (2) Raises the gas ring .100" to give a greater bearing area. (3) To obtain a sufficient thickness of metal between the inside of the top ring groove and the piston crown, the spherical radius of the dished part of the crown has been reduced from 5.580" to 4.750". (4) The lips on the side panelling of the skirt have been omitted. (5) The underside of the head has been scooped out to give a more flexible skirt at the top end, improving the bedding. The piston is ground to EX:7466; this is the most satisfactory shape from a bedding point of view, arrived at as a result of the piston bedding tests carried out on the single cylinder "F" unit. Hs{Lord Ernest Hives - Chair}/L.S.Hall. | ||