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 from Ferodo Ltd. to New Hudson Ltd. detailing the examination of brake shoes and linings.
| Identifier | ExFiles\Box 120\3\ scan0163 | |
| Date | 13th April 1935 | |
| Copy of letter received from Messrs. Ferodo Ltd., 198, Corporation Street, Birmingham. 4. WES/EN. 13th April 1935. Messrs. New Hudson Ltd., St.{Capt. P. R. Strong} Georges Works, Icknield Street, BIRMINGHAM. Dear Sirs, For the attention of Mr. Fraser. We thank you for the opportunity given our Mr. Shilton to examine the eight brake shoes and linings returned to you by one of your customers and would confirm the verbal opinion expressed to Mr. Pratt. The writer understands that the tests, to which these brakes were subjected, were intentionally of extreme severity and that the drum temperatures of the order of 400°C were registered. As we consider the upper temperature limit of Ferodo M.R. to be around 320°C, the linings in question have evidently been well up to standard. Without an examination xx of the brake gear on the car, it is impossible to give a convincing reason for the great disparity in the respective conditions of the near and off side brake linings. The former, particularly on the two leading shoes, are virtually destroyed, whereas the off side linings are in perfect condition, the leading ones showing perfect contact and comparatively little wear and the trailing linings barely bedded to the drums. The above conditions would appear to indicate a partial failure of the lateral equalisers during braking, or, what is more probable, a failure to return of the brake shoes on the near side after the first brake application and consequent slight drag during the high speeds to which the car was accelerated. The latter conditions can easily produce extremely high temperatures which would, of course, be additional to those produced by actual braking. We are forwarding the two linings, removed from shoes, to our Works laboratory and we expect they will be able to give some indication of the respective temperatures to which each has been subjected. | ||