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).
Continued letter regarding tests on port type pumps, relief valves, and pressure capabilities.
| Identifier | ExFiles\Box 139\1\ scan0163 | |
| Date | 12th June 1936 | |
| E.1/HP. 12th June 1936. Messrs.Donald Sessions & Co.Ltd. Continued. (3) Tests carried out on a port type pump, 3/4" bore piston showed a maximum obtainable pressure of 3000 lbs/sq.in. The position is, therefore, that we are equipping our cars with a system on which it is possible to produce pressures up to 5000 lbs/sq.in. The caps on the rams however we have proved by test will leak very badly at 3700 lbs/sq.in.pressure. It is not possible to adopt on production the proposed relief valve scheme because it is entirely untried and the only course open to us is to change over to the original 3/4" bore port type pump on which all our experimental testing, and standardisation tests have been carried out. In the meantime we must push on experimentally with the relief valve scheme in conjunction with the more efficient 9/16" bore valve type pump, so that this can be adopted as soon as we are satisfied and the necessary testing has been completed. We should be glad if you would let us know immediately how soon it will be possible for you to let us have supplies of the 3/4" bore port type pump; we have after careful consideration decided that no cars must be delivered to our customers having any other type of pump but this one. With regard to the leaks from the ram caps, we have examined the sectioned ram, and we should like to | ||