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).
Deflection tests for rear axle pinion bearings.
| Identifier | ExFiles\Box 159\6\ scan0019 | |
| Date | 4th June 1937 | |
| To Rm.{William Robotham - Chief Engineer} from W.Bell. c. Rm{William Robotham - Chief Engineer}/Gry.{Shadwell Grylls} 1371 4.6.37 REAR AXLE PINION BEARINGS. P.III. G.83388 and Bentley GB.2035 The attached charts shew the relative deflections of the inner and outer races under the application of independent thrust and journal loads of 2000 lbs., and their combined effects, also the relative angular movements under an applied torque of 4000 lbs/ins. To produce the combined load effect a total load of 4000 lbs. was applied by means of a balance lever, this being considered a better means of evenly distributing the load than applying two separate 2000 lbs. loads. After testing each bearing as supplied, the equivalent of half the thrust deflection was removed from one of the outer race joint faces, and the tests repeated, these being termed 'pre-loaded' tests. To prove whether or not the direction of the thrust load had any effect upon the results, a final test was made (on the Bentley type) with the thrust load reversed - actually in this latter test the direction of the thrust load was the same as on the chassis - from which it was found that the direction of thrust did not materially effect the results, leading to the conclusion that the frictional force between the faces of the sections of the outer races was greater than the resultant journal effort. 'Pre-loading' the bearings produced a reduction in the 'journal' deflection, but did not affect the 'thrust' deflection. The combined thrust and journal loading results were rather inconsistent. Taking the bearings as supplied, the general effect was a reduction in the journal deflection, the thrust deflection remaining constant. The 'pre-loaded' and 'reversed' tests did not bear this out, but the differences in deflection were actually (not relatively) small. Such small differences of deflection were difficult to register owing to the tendency of the bearing to tilt, but every care was taken, and the tests repeated to verify the results. W.Bell. | ||