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 The Gates Rubber Co. discussing fan belt horsepower test results and performance.
| Identifier | ExFiles\Box 135\1\ scan0219 | |
| Date | 7th October 1938 | |
| The Gates Rubber Co. -2- 7th. October 1938. You will see that the horsepower which the belt has to transmit is greater than that which we estimated when sending you data, being in the neighbourhood of 27 H.P. instead of our figure of 20 H.P. The differences in fan H.P. quoted in the tests aredue to (a) Differences in slip between belts. (b) The fact that fans differing slightly in blade shape were used owing to some blade cracking trouble experienced. We would point out, however, that these tests are being made on a rig under static conditions and at maximum fan speeds, and that we do not know what H.P. the fan absorbs when fitted on a car travelling at, say, 95 m.p.h. - we think it is less than the above figures since we have one of our Manhattan Belt Co. type belts running on a car and no trouble has yet been experienced in service over several thousand miles (although the car has not been driven for long periods at maximum speeds). We hope by developing our belts on these high duty rig tests to obtain a belt entirely satisfactory in service. We would be glad if you could let us have any information about difference in fan H.P. between rig tests and road conditions if you possess anything of the sort. We do not know whether you can improve in any way on the Gates belt which we have tested but will be very interested to hear from you on this point - our only regret is that the Gates belt is not manufactured in this country. We will let you have a full report on our tests when they are completed (we are also testing some Goodyear belts) - in the meantime, many thanks for the interest you are taking in this matter. Yours faithfully, for ROLLS-ROYCE LTD. | ||