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).
Tests conducted on 'V' series pistons and rings.
| Identifier | ExFiles\Box 180\M3\M3.1\ img010 | |
| Date | 22th April 1925 | |
| R.R. 493A (50M) (D.B. 175 25-9-24) J.H.D. EXPERIMENTAL REPORT. Expl. No. REF: Hs{Lord Ernest Hives - Chair}5/L922.4.25. To R.{Sir Henry Royce} from Hs.{Lord Ernest Hives - Chair} c. to W.J. E.J. c. to RG.{Mr Rowledge} E.{Mr Elliott - Chief Engineer} c. to DA.{Bernard Day - Chassis Design} EY. c. to Wcr. S E C R E T. EAC. 'V' SERIES - PISTONS. X8040 X78980 We have tested a set of pistons using 4 standard rings and one wide scraper ring. The oil consumption with these pistons is not materially different from the standard pistons. The proportions of the wide section ring have made it much stiffer torsionally than the narrow ring, which has probably reduced its efficiency as a scraper. The rings also show poor bedding. We are trying to improve the bedding of the rings and are making further tests. We have also run a set of pistons fitted with 5 eccentric rings which are over three times stiffer than the present concentric rings. The oil consumption on the test bed with these rings fitted is approx. 20% less than with the standard rings. It is no better than pistons with grooves below each ring which were tested in France and were not found to reduce the oil consumption to any extent. Hs.{Lord Ernest Hives - Chair} | ||