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).
Wear on aluminium pistons and cylinders, exploring the effects of different lubricating oils and piston ring configurations.
| Identifier | ExFiles\Box 35\2\ scan 243 | |
| Date | 1st November 1920 | |
| X2448 To ES. from R.{Sir Henry Royce} c. to CJ. c. to Bn.{W.O. Bentley / Mr Barrington} c. to Da.{Bernard Day - Chassis Design} c. to By.{R.W. Bailey - Chief Engineer} c. to EFC. R9/G3.11.20. X.2748. RE ALUMINIUM PISTONS. X.1583. X.1434. We are very pleased to hear of the very small amount of wear on the aluminium pistons. The wear on the bore of the cylinders we think is rather great, and although this is not influenced by the use of aluminium pistons, we think it is advisable to find out how far this can be varied by the use of different lubricating oils. I should specially compare the "Castrol R" with the usual Vacuum Oil, which I believe is all-mineral‡ It would also be interesting to find out whether the cylinder wear was greater or less with the increase in the number/of rings. One at first thinks that the piston with six rings might be worse, and then owing to the improved lubrication, and gas tightness, much better. It would also be interesting to find out if it is influenced by wider or narrower rings. One thinks narrow rings would give less wear. Apparently much of the wear is due to grit. Would it pay to use less expensive oil and throw it away more frequently by completely emptying the sump, say, every month, and refilling with new clean oil ? R.{Sir Henry Royce} | ||