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).
Comparison of Wakefield's P.4 mineral oil as an alternative to Silvertown P.4 for use in aero engines.
| Identifier | WestWitteringFiles\V\2January1931-April1931\ Scan070 | |
| Date | 24th March 1931 | |
| To R.{Sir Henry Royce} From Ha/ c. to Sg.{Arthur F. Sidgreaves - MD} Wor.{Arthur Wormald - General Works Manager} c. to Rg.{Mr Rowledge} E.{Mr Elliott - Chief Engineer} c. to By.{R.W. Bailey - Chief Engineer} ORIGINAL Hs{Lord Ernest Hives - Chair}/Dor.{Mr Dorey}3/WJ.24.3.31. x-465. WAKEFIELD'S P.4 MINERAL OIL AS AN ALTERNATIVE TO SILVERTOWN P.4. At the moment we are using Silvertown P.4 Mineral Oil on our aero engines but in order to provide an alternative oil the two "F" Type Tests just completed have been run on Wakefield's P.4. Both brands of oil conform to Air Ministry Specification D.T.D.109. Both oils are derived from napthenic base products and since the world's supply is almost concentrated we think both firms will buy their base products from the same source. Any difference in the two oils will necessarily point to difference in treatment by the two firms. As regards frothing of the oil in the tank the Wakefield product is definitely inferior. Under exactly the same conditions of tackle, flow and temperatures, the Silvertown oil does not froth whereas the Wakefield oil used on the Type Test engines frothed badly - between eight and eighteen inches of froth collected on the top of the oil. If the Carter centrifuger oil cleaner is used frothing is accentuated. With regard to lubricating properties as far as we can judge from the condition of Type Test engine parts there appears to be no difference between that and Silvertown. We had, however, a reduction gear failure on F.39 Type Test using Wakefield's oil but cases of failure have also occurred using Silvertown. There is apparently no difference in the amount of sludge formed by these two oils, this in either case is not serious. At the moment we are not prepared to recommend Wakefield's P.4. as an alternative oil for service use on account of its frothing propensities. We think that by slight modifications to manufacturing methods Wakefield's could produce a non-frothing oil and we are putting the matter to them. Hs{Lord Ernest Hives - Chair}/R.H.Dorey. | ||