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).
Proof tests on the Kestrel 25 engine, specifically focusing on the connecting rods.
| Identifier | ExFiles\Box 179b\3\ img335 | |
| Date | 15th March 1933 | |
| To R.{Sir Henry Royce} From Ha/Fmr. c. to Sg.{Arthur F. Sidgreaves - MD} Wor.{Arthur Wormald - General Works Manager} c. to Rg.{Mr Rowledge} Hy.{Tom Haldenby - Plant Engineer} c. to EP.{G. Eric Platford - Chief Quality Engineer} c. to Mr. Jaques. Ha/Fmr.6/WJ.15.3.33. X2965. X3859. CONNECTING RODS DES.1828. PROOF TESTS ON KES.25 ENGINE. Tests have been carried out to prove the design of the curved foot connecting rods DES.1828 which are fitted to Kestrel 25 engine. The engine, which is fitted with two piece blocks and Goshawk supercharger, was run under Special Category endurance conditions, 891 BHP. at 2750 R.P.M. using special fuel 29/79/10 plus 4 cc's. (iv/Ren/Weth). Castor P.2 oil and L.170 plugs. The running was not continuous, as owing to frequent valve failures on previous running of this description, observations were made each 2 - 3 hrs. of the valve clearances, to avoid terminating the tests through valve trouble. The rods were subjected to a total of 10½ hrs. running under high output conditions, but during this time two valve failures occurred, also after 6½ hrs. running the outer cylinder holding down bolts on B.2 cylinder was found to have failed in the threaded portion flush with the base of the nut. The bolt has a clean fatigue break, over a section line of the bolt which is diagonal by 35° to the length of the cylinder block, the remaining section being an irregular fracture. A further valve failure occurred after 10½ hrs. running when the test was terminated. From the commencement of the test considerable surging occurred, due to blower slip, and became excessive towards the end. The pads are the standard 65° with plain surfaces. The engine was dismantled for examination and the rods and bearings were found to be in excellent condition, and gave no indication of the high output conditions to which they were subjected. The valve failures which occurred form the subject of a separate report. Ha/G.H.Farmer. | ||