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 to Vandervell Products Ltd. discussing the fitting of thrust washers and bearing shells, specifically regarding heat conductivity and dimensions.
Identifier | ExFiles\Box 115\1\ scan0278 | |
Date | 3rd February 1937 | |
1020 Experimental Dept. Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell}4/JH. 3rd. February, 1937. Messrs. Vandervell Products Ltd., Western Avenue, Park Royal, London.W.3. Dear Sirs, We thank you for your letter of the 30th Jan. together with the drawing of the thrust washers. It is noted that you do not recommend the fitting of shells between the bearings and the crankcase on account of the difficulty of conducting the heat away from the bearings. This we appreciate and are taking precautions by making the shells in a forged aluminium alloy, actually R.R. 56, which has the same conductivity as the actual crankcase material, also bedding the crankcase and shell surface together. When in position in the case the shells will be bored out to your measurements and limits prior to fitting the actual bearings. With reference to heat conductivity, we shall surely be better off with regard to the cap half, by using an R.R. 56 shell between the actual bearing and the steel cap, than by using a special cap in which the bearing is actually in contact with the steel cap. We note that the thrust washers have a spigot diameter of 2.413 - 2.418 whereas the outside of the bearing shell is 2.422 diameter so that when in position it is possible for the top half washer to fidget, the bottom half cannot on account of being dowelled. Is this correct and as you intended? It will be some time before we get the engine on test but will let you know the results when completed. | ||