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).
Summary of endurance tests on large type steering rollers, measuring running time to failure under various loads.
| Identifier | ExFiles\Box 153\1\ scan0278 | |
| Date | 20th April 1939 guessed | |
| ENDURANCE TESTS ON LARGE TYPE STEERING ROLLERS. Handwritten note: (Rocking Shaft Torque Load at 9.437") Speed = 450 R.P.M. on roller. Load measured normal to inner tooth surface. TABLE DATA: Column Headers: Type of Bearing, Running time to Cause Failure (with sub-headers: 1220 lbs., 2440 lbs., 3650 lbs., 4870 lbs.), Nature of Failure. Row 1: Type of Bearing: 0.250 Balls. 0.187 Track rad. Adamant Grinding. Running time @ 1220 lbs: 2 hours (Handwritten above: 200 lbs) Running time @ 2440 lbs: 19 mins. (Handwritten above: 400 lbs) Running time @ 3650 lbs: (Handwritten: 600 lbs) Running time @ 4870 lbs: (Handwritten: 800 lbs) Nature of Failure: Balls split. Inner track disintegrated. Row 2: Type of Bearing: 0.187 Parallel Rollers. Adamant Manufacture Running time @ 1220 lbs: 2 hours. Running time @ 2440 lbs: 1hr.55mins. Nature of Failure: Roller ends chipped. Inner track disintegrated. Row 3: Type of Bearing: 0.250 Balls. 0.127 track rad. Chrome steel inner. R & M Grinding. Running time @ 1220 lbs: 2 hours. Running time @ 2440 lbs: 2 hours Running time @ 3650 lbs: 0 hrs. 25 mins. Nature of Failure: Inner track disintegrated. Row 4: Type of Bearing: 0.312 Balls. R & M Manufacture. Incorrect mounting. Running time @ 1220 lbs: 2 hours Running time @ 2440 lbs: 2 hours. Running time @ 3650 lbs: 1 hr. 10 mins. Nature of Failure: Lip of inner broken off. Row 5: Type of Bearing: 0.312 Balls. R & M Manufacture. Correct Mounting. Running time @ 1220 lbs: 2 hours Running time @ 2440 lbs: 2 hours Running time @ 3650 lbs: 2 hours Running time @ 4870 lbs: 1 hour. Nature of Failure: Outer Cracked. Inner track disintegrated. Row 6: Type of Bearing: Timken cone and roller assembly. No.A.4059. Running time @ 1220 lbs: 2 hours. Running time @ 2440 lbs: 2 hours. Running time @ 3650 lbs: 10 mins. Nature of Failure: Rollers crushed. | ||