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).
The performance and failure of Hall's Metal Bearings during testing and comparison with white metal bearings.
| Identifier | ExFiles\Box 114\2\ scan0218 | |
| Date | 25th November 1935 | |
| X1020 To Wor.{Arthur Wormald - General Works Manager} c. to E.{Mr Elliott - Chief Engineer} c. to By.{R.W. Bailey - Chief Engineer} c. to Hl. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer}18/KW.25.11.35. Hall's Metal Bearings. Further to Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer}20/KW.21.9.35. We now have further information as a result of tests on these bearings. After running 13,000 miles in France, Hancock dismantled his engine unit and found the bearings in poor shape. He returned them to us and we agree that though they might have done another 5,000 miles he was correct in arranging to fit a new set. If we compare the results of this test with the results we have previously had with white metal bearings on the small bore engines, we can say that we are in much the same position we have always been in; i.e., that with the flogging the cars get at Chateauroux the bearings only last about 15,000 miles. We are naturally not satisfied with the situation, and we believe the main reason which caused the Hall's metal bearings to fail was very poor adhesion. Careful examination of the bearings in the finish machined condition showed that the adhesion of all the initial sets was very poor. In parallel with the French tests we ran a bench test. The conditions were more severe than any we have previously imposed on a Bentley engine. We can say that in 46 hours of this type of running we should certainly have cracked a complete sets of white metal bearings, so that the failure of the Hall's metal at the end of this time, though disappointing, is not so bad as it might appear. We attach a report on the test. We have now re-erected the engine with bearings the adhesion of which, as far as we can ascertain, is good, and Hancock also has a similar set of bearings. It remains to be seen if their life is substantially increased by this improvement in manufacture. We anticipate better results. | ||