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).
Engine bearing test #5, detailing the procedure, conditions, and results including dimensional changes.
Identifier | ExFiles\Box 173\2\ img228 | |
Date | 21th February 1934 | |
15 February 21, 1934 ROLLS ROYCE ENGINE BEARING TESTS (Continued) Test #5 A test was run this date on an Allison center main bear-ing specification 55-40 (60% Cu, 40% lead, 1% silver). Other bearings, intermediate and end, were the same bearings as used on Tests #1 and #3. All bearings used Rolls Royce type groov-ing and lubrication. Crankshaft used was #4, previously used on tests #2 and #4. The auxiliary booster oil pump was not used as it was not necessary to maintain 68-70 lbs. per sq. in. at 3500 R.P.M. The bearings were run-in under approximately the same conditions as with #3 test up to 3500 R.P.M. The #3 test at 3500 R.P.M. was then duplicated, consisting of a 15 minute run at 3500 R.P.M. followed by 20 diving tests of 30 seconds at 3500 R.P.M. and 1 minute at 2250 R.P.M. This was followed immediately by 15 minutes running at 3500 R.P.M. giving a total time at 3500 R.P.M. of 40 minutes. The bearing temperature averaged about 8°C higher than in #3 test (70-30 center main) and the torque load was about 1% (about 1.2 H.P.) less. The bearing surface was slightly better than on any of the 70-30 bearings tested and the crankshaft appeared and felt smoother than after previous Allison bearing tests. The amount of lead sweated out was less. Center main bearing dimensions were as follows: Before Test After Test Wear Max. diameter 2.9995 3.0017 .0022 Max. Av. diameter 2.9995 3.0007 .0012 Av. Av. clearance 0.0046 0.0059 | ||