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).
Broken bolt on the Goshawk 11 gearbox and proposed solutions.
| Identifier | ExFiles\Box 75\1\ scan0238 | |
| Date | 17th October 1921 | |
| R.R. 199 (250T) (SD676 19-7-17) MP180865 X4247 To Hs.{Lord Ernest Hives - Chair} from R.{Sir Henry Royce} c. to CJ. c. to Wor.{Arthur Wormald - General Works Manager} c. to Br.{T. E. Bellringer - Repair Manager} c. to Da.{Bernard Day - Chassis Design} R4/G17.10.21. X.4247 - RE GOSHAWK 11 - GEAR BOX. With reference to the broken bolt on the side shaft of the gear box, we think this must be caused by the epicyclic action of the ball bearing tightening up the nuts until the bolt has broken. You will remember we had a somewhat similar phenomenon in the "Eagle" gears. We found it was better not to attempt to grip the ball bearing. If we do attempt to grip the ball bearings we must either do so very firmly, or else prevent the ball bearing screwing up the collar, washers, or nuts by castelllations on or in the shaft. This could easily be carried out in the present case by adapting the scheme shewn on our original drawing LeC.1333 at each end of the shaft. This would require the whole length of the shaft counterbored so as to make internal castelllations possible. We could use end castelllations. If you cannot rely on arranging the job so as not to grip the bearing, we suggest that a tube might be used the full diameter of the shaft, namely 3/8" with split pins only, like the sketch we send, and use castelllations in the end of the shaft with suitable washers with face castelllations, then the nuts could be locked with split pins. This scheme would be right whatever the fault, so to save time adopt it if possible See original for sketch. R.{Sir Henry Royce} | ||