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).
Letter concerning test results and pressure issues with hydraulic jacks for the Phantom III chassis.
| Identifier | ExFiles\Box 139\1\ scan0162 | |
| Date | 12th June 1936 | |
| HS{Lord Ernest Hives - Chair}/Gry{Shadwell Grylls} X1166 Copy:- Messrs.R.T.Shelley., Aston Brooke St,Birmingham. Copy:- Hs.{Lord Ernest Hives - Chair} Sft.{Mr Swift} Roy.{Sir Henry Royce} Mx.{John H Maddocks - Chief Proving Officer} E.1/HP. 12th June 1936. Messrs. Donald Sessions & Co.Ltd., 906, Harrow Road, Willesden, LONDON.N.W.10. For the attention of Mr Donald Sessions. Dear Sirs, D.W.S.Hydraulic Jacks for Phantom III Chassis. We have not yet received from you as promised your drawings shewing a proposed relief valve in the hydraulic pump, and we should be glad to have these as soon as possible. As the result of some tests we have carried out during the last few days, we are rather disturbed about the general position. The tests carried out included recording the pressures attainable in the system and the following results were obtained:- (1) Tests on a pump taken from production shewed that it is possible to produce a pressure of 5000 lbs/sq.in in the system; this was a valve type pump having a piston diameter of 9/16". (2) Tests carried out on a pump in use on an experimental car, but which it is believed was originally taken from production, shewed a maximum pressure of 3700 lbs/sq.in; this pump is fitted with ball valves in the piston and in addition has ports in the casting, the piston diameter being 9/16". We do not know how many pumps of this type have been delivered to us. | ||