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).
Torsion test results for a 20 HP crankshaft, from the forging stage to the finished shaft.
| Identifier | WestWitteringFiles\R\2December1927-February1928\ Scan036 | |
| Date | 7th December 1927 | |
| 20 H.P. CRANKSHAFT - TORSION TESTS FORGING TO FINISHED SHAFT COLUMN HEADERS: OPERATION, 15, 19, 21, 22, 31, 33A, 39A, FINISHED SHAFT MAIN BEARINGS No. 1, DIA.: 2.200, =, =, =, =, =, =, 2.000 No. 1, LENGTH: 1.550, =, 1.610, =, 1.540, =, =, 1.525 No. 4, DIA.: 2.200, =, =, 2.030, =, =, =, 2.000 No. 4, LENGTH: 1.500, =, 1.550, =, =, =, =, = No. 7, DIA.: 2.200, =, =, 2.030, =, =, =, 2.000 No. 7, LENGTH: 1.725, =, =, =, =, =, =, 1.800 Nos 2, 3, 5 & 6, DIA.: 2.375 (F), 2.200, =, 2.030, =, =, =, 2.000 Nos 2, 3, 5 & 6, LENGTH: .650 (F), 1.020, 1.070, =, =, =, =, 1.050 CRANK-PINS OUTER, INNER DIAMETER: 0, =, =, =, 1.250, =, =, = OUTER, LENGTH: 1.900 (F), =, 1.625, =, =, 1.530, .750, 1.500 INNER, " ": 0, =, =, =, =, =, =, = INNER, LENGTH: 1.100 (F), =, 1.480, =, =, 1.490, =, 1.560 NOSE OUTER DIAMETER: 1.450, =, =, =, 1.420, =, =, 1.400 INNER ": 0, =, =, =, .625, =, =, = LENGTH: 4.300, =, =, =, 2.520, =, =, 2.500 WEBS DEPTH OPS 1, 6, 7 & 12: 1.015, =, .805, =, =, .795, =, .790 DEPTH OF 2, 3, 4, 5, 8, 9, 10, 11: 1.200 (F), 1.015, .805, =, =, .795, =, .790 WIDTH: 2.550 (F), =, =, =, =, 2.200, =, = TEST RESULTS MEASURED STIFFNESS OF WHOLE SHAFT. LBS. FT./RAD.: 53,000, 41,400, 27,200, 25,600, 22,800, 17,400, 16,400, 15,280 (2 BEARINGS) ∴ STIFFNESS OF ONE WEB WILL BE : LBS. INS./RAD. x 10⁶: 6.08, 4.18, 2.46, 2.33, 2.00, 1.463, 1.365, 1.270 CALC: STIFFNESS ONE WEB. LBS. INS./RAD. x 10⁶: 3.765 (APPROX. VALUES ONLY), 3.39 (APPROX. VALUES ONLY), 2.39, 2.272, 2.205, 1.607, 1.577, 1.46 (7 BEARINGS) RATIO: CALC: STIFFNESS / TEST STIFFNESS: .620, .811, .971, .9725, 1.103, 1.098, 1.155, 1.15 RATIO: TEST STIFFNESS / FINISHED STIFFNESS: 3.47, 2.71, 1.78, 1.675, 1.49, 1.14, 1.07, 1.0 MEASURED LOSS OF STIFFNESS PER WEB (EACH OP.) x 10⁶: 1.900, 1.720, 0.130, 0.330, 0.537, 0.098, 0.095 CALC. LOSS OF STIFFNESS PER WEB (EACH OP.) x 10⁶: 0.375, 1.000, 0.118, 0.067, 0.598, 0.030, 0.117 RATIO: CALC. LOSS / ACTUAL LOSS: .197, .582, .900, .203, 1.110, .306, .123 | ||