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 of torsional vibrations for a Flat 12 Cylinder 4 Stroke engine.
| Identifier | ExFiles\Box 132\2\ scan0190 | |
| Date | 26th October 1940 guessed | |
| SHEET 1 FLAT 12 CYL 4 STROKE TORSIONALS This sheet compares directly (for amplitude) with B 60 sheets 3, 4 and 5. The calculations are for an engine of Ph. III dimensions (3 3/4 x 4 1/2) having an undamped crankshaft. M.E.P. curve, sheet 7 has been used for calculating the gas torque component. FIRING ORDER A 1 4 2 6 3 5 B 2 6 3 5 1 4 Left Y-Axis: Vibration amplitude at the free end of the crankshaft. +- DEGREES Right Y-Axis: LB/SQ. INCH. maximum stress at the node. X-Axis: Crankshaft R.P.M. Graph Peaks (Order Numbers): 12, 11 1/2, 10 1/2, 10, 9 1/2, 8 1/2, 8, 7 1/2, 6 1/2, 6, 5 1/2, 4 1/2, 4, 3 1/2, 2 1/2 Graph Annotation: 2/ REV. MAX. AMPLITUDE @ 6220 RPM = 9.2° Top left corner: 6 | ||