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).
Test report comparing the life of Patent Brake Shoes against Standard Rivetted Shoes.
| Identifier | ExFiles\Box 120\1\ scan0090 | |
| Date | 1st September 1931 | |
| Particulars of test made in September 1931 to ascertain the comparative life of linings. (a) On Patent Brake Shoes (b) On Standard Rivetted Shoes ******************************** These tests were made on our Brake Testing machine running at 300 revolutions per minute. The brakings were for the duration of 15 and 30 seconds against a pull of 60 h.p. as indicated by an ammeter on the motor, and there was a rest of four minutes between each braking. The linings used were M.R. Ferodo. Two Millenite Brake Drums were employed made from the same cast of metal, and these were changed over from the Patent Shoes to the Rivetted Shoes every 200 runs. The temperature attained by the Brake Drums averaged about 220 Centigrade for the runs of 15 seconds duration and 350 Centigrade for the runs of 30 seconds duration. The life of the linings was as follows :- Patent Shoe. 1500 Runs - 15 seconds 500 " - 30 " 1500 " - 15 " 177 " - 30 " ----------- 3677 Runs. Rivetted Shoe. 1500 Runs - 15 seconds. 450 " - 30 " ----------- 1950 Runs. The Rivetted shoes were removed from the machine after 1200 runs for the purpose of knocking the rivets back. This operation was repeated three times in all so that every chance was given to the rivetted Shoes. | ||