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 repair of a fractured fan and a test on variable speed fan pulleys.
| Identifier | ExFiles\Box 135\4\ scan0019 | |
| Date | 12th May 1939 | |
| 1135 EXPERIMENTAL DEPARTMENT. Rm{William Robotham - Chief Engineer}/Ed.{J. L. Edwards}9/JH. 12th. May, 1939. Messrs. Ferodo Ltd., Chapel-en-le-Frith. For the attention of Mr. Longley. Dear Sirs, Many thanks for your letter, and the fractured fans which came to hand today. To enable you to get your rig running again as soon as possible, we are repairing the first fan by fitting a new blade in place of the broken one, and proceeding meanwhile with the manufacture of two more fans. As you will realise, it is quite possible that this repaired fan will fail again before long, but it may be sufficient to keep you going until the new fans are ready. We have a test in mind which will employ expanding fan pulleys to give a variable fan speed with engine speed, working on the principle of allowing the belt to run up and down the 'V' of the pulley. Naturally the narrower the 'V' angle the less the axial movement of the pulley sides necessary for a given increase in effective diameter, and we should be very glad therefore if you could let us know the narrowest angle you consider would work satisfactorily on a belt. We hope to despatch the repaired fan to-morrow. Yours faithfully, FOR ROLLS-ROYCE LTD. | ||