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).
Graph showing the results of a torsion test on a 20 HP crankshaft from forging to finished shaft.
| Identifier | ExFiles\Box 6\1\ 01-page093 | |
| Date | 6th November 1919 | |
| FORGING DIMENSIONS: (AVERAGE) A.{Mr Adams} 2.375" JOURNAL | E.{Mr Elliott - Chief Engineer} 1.200" OUTSIDE FLASH B. 1.900" CRANKPIN | F.{Mr Friese} 2.850 WEB WIDTH C. 1.100" WEB (THK) | G.{Mr Griffiths - Chief Accountant / Mr Gnapp} 4.625" CRANK RADIUS D.{John DeLooze - Company Secretary} 1.350" INSIDE FLASH | INITIAL CRANKRADIUS 2.250" 20 H.P. CRANKSHAFT – TORSION TEST. FORGING TO FINISHED SHAFT. TORQUE ON NOSE — LBS. FT. ANGULAR DEFLECTION — DEGREES. ① AS FORGED. ② JOURNALS TURNED FROM 2.375 DIA TO 2.140 DIA. ③ CRANK PINS TURNED FROM 1.900 TO 1.625 DIA. WEBS 1.305 THICK. ④ JOURNALS REDUCED FROM 2.200 TO 2.030 DIA. 5 JOURNALS BORED 1.250 DIA 6 WEBS PROFILED FROM 2.850 WIDE (FORGED) TO 2.200 WIDE ⑦ CRANKPINS REDUCED FROM 1.625 TO 1.530 DIA. ⑧ CRANK PINS BORED .750 DIA. (FINISHED) BULK REDUCTION IN STIFFNESS PER OP. 32.5% 35% 7% 10.5% 18% 6% 6% | ||