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).
Report page detailing further tests and conclusions on Vandervell bearings, comparing tri-metal and lead-bronze types.
| Identifier | ExFiles\Box 115\4\ scan0115 | |
| Date | 10th September 1940 guessed | |
| - 4 - Since writing the above report a further two tests have been completed on Vandervell bearings with the object of (a) Settling the claim by Vandervell that the conditions imposed by the insertion of their strip bearing in a steel housing are much more arduous than those imposed by inserting the bearing direct in the crankcase. (b-) Providing a direct comparison between the tri-metal bearing and the lead-bronze bearing of Vandervell manufacture. Both the lead bronze and the tri-metal bearing were oval and barrel shaped in a similar manner to that run on No.10 test. The results of both these tests are summarised on page 7. and both must be somewhat disquieting to Vandervell. It will be seen that failure of the lead-bronze bearing commenced during the first half hours load running and that although the test was discontinued after only 7½ hours complete break-up of the bearing was imminent. The tri-metal bearing successfully completed 10 hours endurance running but cracking was again apparent in places; bedding was fairly even but the appearance of the whole of the bearing surface was rough suggesting early trouble with break up. Normal running temperatures of the lead-bronze and the tri-metal bearing appeared to be similar, but both bearings appeared to run at about 10°C higher temperature than the similar bearing carried in a steel housing. This is probably an illusion due to the fact that thermocouple in the latter case bears up against the steel shell and not against the lining itself. The following conclusions may be drawn from these tests:- 1. All the R.R. lead-bronze alloys tried for main bearings are considerably more satisfactory than the lead-bronze alloy produced by Vandervell. 2. Conditions imposed by inserting the thin shell in a steel liner are inherently no more difficult than those imposed by inserting a thin shell bearing direct in the crankcase - as regards break up. This may not necessarily be true as regards seizure properties. P.T.O. | ||