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).
The effects of speed and heat on brake lining wear and friction.
| Identifier | WestWitteringFiles\L\2Jan1924-March1924\ Scan12 | |
| Date | 12th July 1928 | |
| R.R. 493A (40 H) (SL 42 12-7-28). J.H., D.{John DeLooze - Company Secretary} -2- Expl. No. x9910 REF: Hs{Lord Ernest Hives - Chair}/Rm{William Robotham - Chief Engineer}/LG22.1.24. EXPERIMENTAL REPORT. We therefore carried out a second series of tests to demonstrate the magnitude of these effects. It will be observed that speed and heat both decrease the wearing capacity of the normal lining. Once the lining had become thoroughly roasted, its wearing qualities decreased by about 80%, while its co-efficient of friction increased by something over 30% - both presumably due to the burning out of the impregnating material. We have given 3 curves in graph.X. showing the mechanical gain that we got out of the servo :- (1) After it had just been relined. (2) After the lining had been run until the drum attained a red heat. (3) After a considerable number of tests had been run with the shoes at a high temperature. All these latter tests were carried out with the same servo and shoes. We believe, after further tests, that the wearing down of the Ferodo until the copper rivets come in contact with the drum, has something to do with the apparent increase of co-efficient of friction which we have measured. We are making tests to confirm this. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} contd:- | ||