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).
Improvements to Phantom cylinder blocks to avoid bore distortion and consequent piston knocks.
| Identifier | ExFiles\Box 65\4\ scan0365 | |
| Date | 25th June 1927 | |
| To BY.{R.W. Bailey - Chief Engineer} from E.{Mr Elliott - Chief Engineer} c. to BJ. Hs.{Lord Ernest Hives - Chair} Y8050 E2/M25.6.27. PHANTOM CYL. BLOCKS. X.8030 Y8050 X.5030 We send you herewith LeCs. 2428/9 dealing with improvements to the Phantom cyl. blocks to avoid distortion of the bores, and consequent piston knocks. We believe that OY. has gone over with you the experiences of the American Co., in which they experienced actual failures in the form of cracking opposite the middle barrels of each block on the steering side of the engine. These troubles in the U.S. were accentuated by three factors :- (1) The machined face of the cyl. had been cut back into a narrow strip along one edge of the block. (2) The castings on which the failures were experienced were considerably below drg. side on the thickness of the broken web. (3) The cyl. iron used by RR. of America is much softer than English cast iron. Nevertheless we understand that it was found actual distortion could be measured in the bores of the skirts during an investigation at Derby, and it is agreed that with the cyl. block constructed as it is with inserted tubes instead of cast bosses surrounding the studs, some extra support is necessary. The permanent alteration we propose to make is shewn on LeC.2428. LeC.2429. shews a means of using any existing cyl. blocks by strutting the water door opening. This matter should be pushed forward with all possible speed, and experimental tests should be made to measure what distortion remains after these alterations have been made to the cyl. blocks. The 20 HP. engine cyl. block will also require somewhat similar attention, and we shall be glad if you could help us out in this matter by making similar drgs. for the 20 HP. to those we send you herewith. E.{Mr Elliott - Chief Engineer} | ||