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).
Development and testing of various piston designs, including issues with flexibility, seizure, and over-oiling.
| Identifier | ExFiles\Box 77\3\ scan0201 | |
| Date | 29th December 1919 | |
| R.R. 235 A (100 T) (S.F 846 6-8-19) G.{Mr Griffiths - Chief Accountant / Mr Gnapp} 2460 Contd. -2- Hs{Lord Ernest Hives - Chair}5/LG29.12.19. non-pressure side to form the spring. These look very promising. If they collapse, however, in the same way as the present ones, we might try fixing a cantilever spring off the gudgeon pin bosses, to prevent this occurring. We have run some cast iron pistons of the old standard type which had been split. We had these pistons ground the same size as the bore. We ran these in the cylinder under all sorts of conditions without any signs of seizure. The point against them appears to be that in their present form, when split, they are too flexible. We are making further experiments with the cast iron pistons using the letter-box slit as well as the standard split. X.3715. X.3743. The plunger pistons are going very well - we are running a set on 48-GB. The over-oil, but not bad enough to cause the Lodge plugs to miss-fire. We think the spring as well as the oil pressure will be a greatly help on these pistons. There is a tendency for these pistons to knock when hot; we think this is due to the oil leaking out and not being replaced quickly enough. We are hoping to get a set of these pistons sufficiently good to be fitted into the 10,000 mile car (2.EX) which leaves the Works in a weeks time. Hs.{Lord Ernest Hives - Chair} | ||