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).
Test results and conclusions for old and new type oil cooler matrices.
| Identifier | ExFiles\Box 131\1\ scan0144 | |
| Date | 11th November 1935 | |
| -2- Hs{Lord Ernest Hives - Chair}/Std.28/KW.11.11.35. (3) Measurements of maximum oil pressure on cooler under cold starting conditions. The cooler was run on an engine, using an oil whose viscosity reproduced approximately 0°C. air temperature starting conditions. The engine was run straight up to 4500 r.p.m. and the maximum oil pressure (inlet to cooler) was noted - 125 lbs/sq.in. (Note: engine was fitted with small type pump and old type relief valve. (4) New type - LeC.4386 - matrix was pressure tested at atmospheric temperature until leakage occurred. This commenced at 180 lbs/sq.in. (5) New type - LeC.4386 - matrix was pressure tested at 130°C. inlet oil temperature until leakage occurred. This commenced at 100 lbs/sq.in. A similar test was carried out for the Buick cooler. This gave no leakage up to 150 lbs/sq.in. Conclusions. From test (1) the pressure drop across either matrix is such a small part of the total pressure that changing from LeC.3756 to LeC.4386 will not materially reduce the total pressure on the matrix and will certainly not justify the resultant loss in cooling. From tests (4) and (5) it is seen that the strength of the matrix has fallen off with the temperature, indicating the need for the employment of high temperature solder. Summary. We suggest that we should revert to the old type matrix LeC.3756, using a special high temperature solder and stiffening up the bottom cover plate of the matrix by ribs. We are going to rebuild one of the new matrices using a suitable high temperature solder, and re-test it to confirm the above results. Hs{Lord Ernest Hives - Chair}/C.S.Steadman. | ||