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).
Answers to questions regarding engine materials and components like lead bronze, piston rings, and superchargers.
| Identifier | ExFiles\Box 88\1\ scan0265 | |
| Date | 23th October 1936 guessed | |
| FILE. 261. Answers to Questions submitted by Mr. Kennington for Rolls-Royce Lead Bronze has lost ground to some extent in Motor Cars, although it does hold its own in Aviation. Oil absorption of lead is still the main objection. Lowering of loads is the general trend. However, high lead babbitts are being reconsidered. Handwritten note: 14B. Babbitt 1/16" Thick 4% Sn.{Mr Sanderson} 8% Pb. There is no panacea for bore wear, except a calibration of the oiling system to give sufficient oil on the bores, and calibration of Piston Rings to minimize blo-bi and control cylinder wall oil to a point that rings are slightly wet. -- Over control during initial running is not good. This must be watched, because damage is done in the first 500 miles that becomes progressive. Ring weight is more important than radial thickness or tension, in blo-bi control. High point tension for 15° each side of gap seems to be very beneficial. Tungsten steel rings press fitted into counterbore seems preferred practice for Valve seat inserts. Superchargers have made little headway, although they will become prevalent as two cycle Diesels become better known. This latter development is growing fast. Handwritten note: 3 blade spiral Roots blower. | ||