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 a supplier regarding the decision to adopt Silico-Manganese and a new spring design based on American findings.
| Identifier | ExFiles\Box 52\2\ Scan155 | |
| Date | 5th October 1927 | |
| Messrs. Thos. Firth & Sons Ltd., Norfolk Works, Sheffield. 5th Oct. 1927. -2- You will probably be surprised by this result, but it is in accordance with similar experiences we have had when comparing the two materials previously, the earlier tests having been carried out by comparing springs produced by Messrs. Lemoines and springs produced by our American associates with our standard product. There is one other feature which we consider of very great importance, namely, that as a result of constant failures our American associates redesigned their springs entirely, starting from a different basis from that mutually adopted, and as a result they reported a very much increased life for the road spring. We therefore ordered 2 sets of front springs from America produced in their Springfield Works to their own designs and although the springs in question gave an increase deflection of approximately 25% for the same weight of steel in a spring, the average life of the American springs we have tested out at our Works was 39 1/2 hours, the material was Silico-Manganese, the top plates being forgings machined all over. Mr. F. {Mr Friese} H. {Arthur M. Hanbury - Head Complaints} Royce, our Engineer-in-Chief, has therefore come to the conclusion that we should not only adopt Silico-Manganese as our standard material, but re-design our springs on the same basis as that adopted by our American associates. We are, therefore, obtaining blueprints from America covering their design factors and methods of production. As soon as these are available, we propose to submit them to you with instructions to produce springs along these lines in the future. This, however, will entail some little delay, but at the same time we appreciate that you will have a certain stock of material rolled suitable for springs. We therefore think it desirable that you should carefully weigh up your position and then we would like to arrange a meeting between yourselves, Mr. Wormald and certain other representatives of this Company, in order to get down to exactly what we propose to do in the circumstances and find out the earliest possible moment we can go on to the use of Silico-Manganese as a material, and consider the question of producing the new design of spring as our standard for the future. Yours faithfully, FOR ROLLS-ROYCE LIMITED. 2 sets prints encl. Technical Production Engineer. | ||