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).
Rejecting Fafnir ball bearings due to non-compliance with specifications and excessive noise.
| Identifier | ExFiles\Box 20\7\ Scan096 | |
| Date | 13th August 1920 | |
| R.R. 199 (250T) (SDg96 19-7-17) MP 18.865 x3906 HS{Lord Ernest Hives - Chair}2/LG13.8.20. To EWT. U.S.A. Dept. from Hs.{Lord Ernest Hives - Chair} c. to Wor.{Arthur Wormald - General Works Manager} c. to By.{R.W. Bailey - Chief Engineer} c. to Da.{Bernard Day - Chassis Design} ------------------- X.3907. BALL BEARINGS. X.3906. With reference to Mr. Olley's memo, ref:- "Qy4/G 29.7.20, we received in May, 15 Fafnir Ball bearings but we received no definite instructions for what reason these bearings were sent to us, however, we assumed that they were in connection with the cars to be built in America. These bearings appear to have been casually selected. 1. The bearings all have cages made from pressed sheet steel. In our choice of bearings we have always endeavoured to obtain brass or bronze cages. 2. All the races have slots in the inner and outer races through which the balls are inserted. On a lot of the bearings this is direct contrary on our specifications. We insist that wherever Journal bearings take any thrust they should be of a type without slots. This is shown on our supervision sheets. 3. We also specify clearly on our supervision sheets that one bearing for the 1st. Motion shaft and the bearing for the 2nd. Motion shaft in the gear box should be special deep grooved type. These bearings have to take the thrust on the helical continuous gears. The bearings we have received are just the ordinary type. 4. We have tested these bearings for noise and find that they are not as good as the Hoffman. We reject, at Derby any Hoffman bearings which are as noisy as these Fafnir bearings. The bearings we are most particular about are the gearbox bearings. We do not think any useful purpose would be served in carrying out any extensive tests with the Fafnir bearings. We think the policy of springfield should be to take out specifications for ball bearings and the drawings of the Contd. | ||