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 to reproduce a connecting rod bearing failure on an E.A.C. engine.
| Identifier | Morton\M3.5\ img022 | |
| Date | 16th April 1925 | |
| R.R. 493A (50H) (D.B. 175 25-9-24) J.H.D. EXPERIMENTAL REPORT. To R.{Sir Henry Royce} from Hs.{Lord Ernest Hives - Chair} c. to CJ. BJ. c. to RG.{Mr Rowledge} E.{Mr Elliott - Chief Engineer} c. to DA.{Bernard Day - Chassis Design} BY.{R.W. Bailey - Chief Engineer} c. to Wor.{Arthur Wormald - General Works Manager} Expl. No. REF: Hs{Lord Ernest Hives - Chair}6/L26/16-4-25 SECRET CON. ROD BEARING FAILURE ON E.A.C. ENGINE. 93NK [Handwritten]: V8030 V8010 The EAC! test bench engine was run with the object of reproducing a con. rod bearing failure. The test was run at 2500 r.p.m. with the oil temp. at 100°C. Vacuum oil was used. The oil pressure was reduced step by step until it was 7 lbs/sq.in. but no bearing trouble resulted, [handwritten: with the minimum, after 4 hrs running] the speed was then increased to 2750 r.p.m. the oil temperature and pressure maintained the same. After 14 mins. at this speed No. 2. big end bearing ran, the white metal had completely disappeared. On examination of the engine it was found that part of the metal had left No.6 big end. Bearings Nos. 2, 3, 4 and 5 have run a total time of 430 hrs. and Nos. 1 and 6 888 hrs. Most of this running has been at high speeds. The main crankshaft bearings were undamaged. The con. rod bearings had worn themselves to an excellent bedding. We might find when this test is repeated, that rods which have not bedded themselves in, will fail more quickly. Hs.{Lord Ernest Hives - Chair} | ||