Material change from aluminium to cast iron for the Peregrine J.111 crankcase and cylinder block.
| Identifier | ExFiles\Box 5a\1\ 01-page216 | |
| Date | 15th September 1931 | |
| V5770. BY.3/G.15.9.31. PEREGRINE(Experimental Bentley car never produced / Aero Engine) - J.111. Referring to E.1/M.14.9.31. I note that we are to produce the top half crankcase and the cylinder as a unit, and that the material is to be Cast Iron, and further that we are to use inserted liners. Nor. told me that it had been decided to change from aluminium to cast iron for the top half crankcase and cylinder block unit. I am still not clear whether this proposal is limited to 'Peregrine(Experimental Bentley car never produced / Aero Engine)' or applies to J.111. also. Now that we are using a cast iron block we would remind you that quite a number of firms are using a press fit between the cylinder liner and the block, as a means of making a water tight joint. The Sheepbridge Iron Co. who specialise on cylinder barrel castings are very definite in their opinion that a plain press fit with no rubber joints is the best form they have had to deal with. I am getting the exact figures for the interference fit that they recommend in the case of the ordinary cast iron. I think it is .003 per inch of diameter, and for nitralloy cast iron .0015, but I have written to confirm these figures, and will let you have this information later. BY. {R.W. Bailey - Chief Engineer} BM [STAMP: RECEIVED 16 SEP 1931] | ||
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).