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).
Test report on Bentley rear axle pinion bearings to investigate the effects of tilted outer cages.
| Identifier | ExFiles\Box 115\2\ scan0593 | |
| Date | 5th September 1938 | |
| REPORT ON TEST NO. 904.B. SHEET 1. (2 SHEETS) 5.9.38. OBJECT OF TEST: Bentley rear axle pinion bearing tests for Rolls Royce. To investigate the effects upon the cages when the outers are tilted .004" across and in the direction of the journal load. BEARINGS: 5/MDJT.30. (for special features see detailed report below). SPEEDS: 500, 1000. LOAD APPLIED: The equivalent to service conditions in various gear loading. Top gear: 1350 lbs. (J.{Mr Johnson W.M.}) 2040 lbs. (T.) at 4500 R.P.M. (4¼" litre engine). 2nd. Gear: 2050 lbs. (J.{Mr Johnson W.M.}) 3000 lbs. (T.) at 3000 R.P.M. (4¼" litre engine). NOTE: All tests conducted on horizontal rig as shown on drawing TR.{Capt. F. W. Turner - Finance}79. The maximum permissible thrust load for this type of rig is 2200 lbs. In all tests the outers were tilted by means of distance pieces ground out of parallel. LUBRICANT: Wakefield's Hi-press E.P. Oil. (bath). TEST No.1. Bearing fitted with steel cages (C.C. .006") weakened by 50% on faces by reducing .027". Tested at 1000 R.P.M. 1350 lbs. (J.{Mr Johnson W.M.}) and 2040 lbs. (T.) load. After 100 hours test the cage on the thrust side had broken across one ball hole. In this test the tilt was applied at right angles to the journal load. Max. Temp. Rise: 54°F.{Mr Friese} Normal Temp. Rise 50°F.{Mr Friese} TEST No.2. Bearing with similar weakened cages (C.C. .016") now tested at 500 R.P.M. 2030 lbs. (J.{Mr Johnson W.M.}) and 2200 lbs. (T.). After 22 hours the thrust side cage again smashed. Max. Temp. Rise: 53 F.{Mr Friese} Normal Temp. Rise 50°F.{Mr Friese} TEST No.3. Identical with above test but cage clearance of .020" and after 100 hours test under similar conditions found to be in excellent condition. Max. Temp. Rise: 68°F.{Mr Friese} Normal Temp. Rise 59°F.{Mr Friese} TEST No.4. Fitted with steel cages (C.C. .006") the ball holes of which were elongated .013". Tested at 1000 R.P.M. under 1350 lbs. (J.{Mr Johnson W.M.}) 2040 lbs. (T.) loads. After 51 hours test the bearing was in excellent condition. Max. Temp. Rise. 78°F.{Mr Friese} Normal Temp. Rise. 76°F.{Mr Friese} TEST No.5. Using the same bearing as in Test No.4 at 500 R.P.M. under 2030 lbs. (J.{Mr Johnson W.M.}) and 2200 lbs. (T.) loads. After 40 hours the cage on the thrust side had broken through one ball hole. Max. Temp. Rise. 78°F.{Mr Friese} Normal Temp. rise 74°F.{Mr Friese} TEST No.6. Bearing fitted with steel cages (C.C. .006") the ball holes elongated .025", ran under similar conditions to Test No.5 and after 100 hours test was found in excellent condition. Max. Temp. Rise 75°F.{Mr Friese} Normal Temp. Rise 70°F.{Mr Friese} TEST No.7. Bakelite cages manufactured to standard steel cage drawing but with cage clearance of .020" now tested at 1000 R.P.M. 1350 lbs. (J) 2040 lbs. (T) loads. After 40 hours run the cages were found to be O.K. Max. Temp. Rise: 53°F.{Mr Friese} Normal Temp. Rise: 50°F.{Mr Friese} | ||