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 Ferodo Ltd. regarding the testing of different brake materials and their characteristics.
Identifier | ExFiles\Box 26\4\ Scan212 | |
Date | 1st January 1924 | |
X3407 X719 Hs{Lord Ernest Hives - Chair}2/LG. (1st. Jan.) 1.1.24. Messrs. Ferodo Ltd., Sovereign Mills, Chapel-en-le-Frith. Dear Sirs, For the attention of Mr. Field. In connection with the complaints of squeaking brakes we have been testing other materials. We have carried out tests with 'Halo' made by The Scandanavia Belting Co. So far we have not been able to produce squeaking brakes with this material, it also appears to be kinder to the brake drums. The co-efficient of friction appeared to be somewhat higher than Ferodo when cold but it rapidly loses its co-efficient as it becomes hot, in fact, if it is used on a 2-wheel brake car, it can become dangerously ineffective. The point of interest to us, however, was the fact that it did definitely appear to reduce the squeaking also it had the advantage of not cutting up the drums. At the present time we are carrying out a number of tests on different types of brakes. It is difficult for us to give any definite value to these until we know the characteristics of your brake material. We should like to know whether you have any particulars as regards how the co-efficient varies with heat and drum speed. If you could kindly let us have this information, it would materially assist us. You have, at times, very kindly invited us over to see your methods of testing. When convenient to you we should be very pleased to take advantage of your kind offer. contd:- | ||