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 Leyland Motors discussing the performance and seizure issues of A.C.6 versus R.R.56 bearing materials.
Identifier | ExFiles\Box 116\3\ scan0053 | |
Date | 3rd December 1937 | |
1020a Rm{William Robotham - Chief Engineer}10/R.{Sir Henry Royce} 3rd December, 1937. Messrs. Leyland Motors Limited, LEYLAND. Lancs: Dear Sirs, Thank you for your letter of the 2nd December with reference to the A.C.6 bearings you have been running. We note what you say about seizure. Our experience has been rather different to your own, but then our bearings receive different treatment. Almost all our failures are experience at high speed running about 4-4,500 engine revs. We find that with R.R.56 bearings seizure is likely to occur with any suggestion of oil shortage. A.C.6 bearings are rather less temperamental. This discrepancy between the two bearing materials is accentuated when they are used on main bearings where the loading is more constant, and, in consequence, the tendency to oil film rupture is great. We find it quite impossible to run R.R.56 in a 6-cylinder engine as a main bearing, whereas A.C.6 has been our standard production material on the Bentley for the past two years. Yours faithfully, For ROLLS-ROYCE LTD. | ||