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).
25/30 HP engine oil consumption tests comparing standard and L-shaped piston rings.
| Identifier | ExFiles\Box 144\3\ scan0103 | |
| Date | 1st August 1936 | |
| +1220 To H.{Arthur M. Hanbury - Head Complaints} c. to WOT. c. to Hy.{Tom Haldenby - Plant Engineer} c. to EX. c. to Hd.{Mr Hayward/Mr Huddy} HE/FD.{Frank Dodd - Bodies}12/JH.1:8.36. 25/30 HP Oil Consumption Tests. In conjunction with the test beds, we have carried out oil consumption tests on GAE-20 and 21-G-IV, to ascertain a value for the L shaped compression rings. Consumption figures were taken on GAE-20 with the standard rings fitted and again with the top two rings changed to the L shape type. The test was repeated on 21-G-IV but in this case only one (the centre ring) was changed for an L type. The results show that one L shaped ring is as good as another, that with one fitted the consumption is improved by 150% and with two fitted an improvement of 266% is obtained. Herewith are the comparative figures :- GAE-20 Miles run. Average speed. Average oil temp. Average air temp. Oil consumption Standard rings. 195 45.9 m.p.h. 79.7°C. 24.7°C. 390 M.P.G. Top L shape rings. 196 52.0 M.P.H. 83.5°C. 18.4°C. 1,425 M.P.G. 21-G-IV. Miles run. Average speed. Average oil temp. Average air temp. Oil consumption Standard rings. 191 45.3 M.P.H. 77.0°C. 17.7°C. 361. M.P.G. Middle ring only L shaped. 200 49.0 M.P.H. 82.4°C. 16.5°C. 914. M.P.G. Attached Drawing No. Rn.{Mr Robinson}186. HE/F.Dodd . | ||