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 plotting torsional vibration amplitude against crankshaft RPM, showing the separate effects of gas torque and inertia torque for a B60 engine.
| Identifier | ExFiles\Box 132\2\ scan0194 | |
| Date | 26th October 1940 guessed | |
| SHEET 5 B 60 TORSIONALS THE SEPARATE EFFECTS OF GAS AND INERTIA TORQUE. Torsionals due to gas torque only. M.E.P. curve sheet 6 used for these calculations. Torsionals due to inertia only. The calculations are for an undamped crankshaft to RE 869 (2.75" journals, 2" crankpins). FIRING ORDER 1 4 2 6 3 5 vibration amplitude at the free end of the crankshaft. DEGREES Crankshaft R.P.M. LB/SQ IN. Maximum stress at the node. Graph Peaks (from left to right): 6, 5 1/2, 5, 4 1/2, 4, 3 1/2 MAX. AMPLITUDE = 3° FOR GAS ONLY. 3/REV MAX. AMPLITUDE @ 5050 RPM = 1.05° FOR INERTIA ONLY. 2/REV. MAX. AMPLITUDE @ 7575 RPM = 6.95° | ||