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).
Proposal to address wear on driving keys in Phantom III and Bentley rear hubs by fitting an intermediate driving piece.
| Identifier | ExFiles\Box 92\4\ scan0239 | |
| Date | 16th October 1936 | |
| x306 BY.2/G.16.10.36. Ly/Hvy. Hs.{Lord Ernest Hives - Chair} Scl. RO{C. C. Rose - Export Manager}/W Ho/Tun. PHANTOM 111 and BENTLEY REAR HUBS, PIECE NOS. G.81903/4 and GB.519/20. RE: WEAR OF DRIVING KEYS IN HUB. The proposal put forward in E/Hdy.{William Hardy}4/HP.13.10.36. to produce the hub in nickel steel of a brinell of 286 to 311 with the object of overcoming the wear on the keys will not be satisfactory. Nickel steel of a brinell even as high as 341 picks up and tears badly under working conditions. In addition to this, the hub will be very much more costly to produce. It appears to me that the rational way of dealing with the matter is to fit an intermediate driving piece between the keys in the hub and/the keys on the driving dog. This piece will be made a press fit into the serrations on the hub, it can be made in either aluminium bronze which I think would be perfectly satisfactory or if found desirable air hardened steel. I would suggest that the keys in the hub are produced on a taper of 1 in 200 i.e. the axis of the hub is thrown this much out of line when the keys are slotted. By doing this we can assure a tight fit between the intermediate double keyed annulus and the hub into which it will be forced. This scheme will recover all the hubs which are in service, and are giving trouble, in addition it means that no hub would be scrapped, as in the event of wear the intermediate piece only would be thrown away. BY.{R.W. Bailey - Chief Engineer} | ||