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).
Balancing of fans, highlighting issues with breakages on the Bentley fan.
| Identifier | ExFiles\Box 86\5\ scan0039 | |
| Date | 3rd May 1935 | |
| Sft.{Mr Swift} [crossed out] c. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} c. BY/CS. [crossed out] c. Man [crossed out] 4224 BY.13/G.3.5.35. CHASSIS - RE: BALANCING OF FANS. ------------------------- In view of the higher speed at which engines are now being used regularly, it is most important that we should balance the fan dynamically. This may not be possible owing to want of equipment immediately, but we should obtain the necessary equipment as soon as possible. In the meantime we must make sure that the best is being made of static balancing by using a light hollow mandrel, hardened, and also use hardened knife edge. The need for this has been emphasized by the breakages which have occurred on the Bentley fan. Since we increased the rivets any further trouble has been directly due to want of balance, in one particular fan which has broken the spindle off, the out of balance was as much as 1/4 oz. on the end of the blade. This at the high revs. which the fan runs at represents quite a high alternating load and one which the spindle was not capable of carrying. BY.{R.W. Bailey - Chief Engineer} [signature] | ||