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).
Data sheet detailing performance calculations and comparisons for engine main bearings.
| Identifier | ExFiles\Box 115\2\ scan0500 | |
| Date | 26th October 1939 | |
| -4- Rm{William Robotham - Chief Engineer}/TAS.{T. Allan Swinden}9/JH.26.10.39. MAIN BEARINGS. Bentley V figures 12 HP. 4 Cyl. from By/B.6/G.{Mr Griffiths - Chief Accountant / Mr Gnapp} 5.12.38. Peripheral speed at journal at 4500 r.p.m. 39.3 ft/sec. 38.22 ft/sec. " " " " " 3500 r.p.m. 30.5 ft/sec. Max. pressure on Bentley V bearing due to gas and inertia at 3500. 1130 lb/in.sq. Estimated max. pressure on Bentley V bearing at 4500 r.p.m. 1860 lb/in.sq. Maximum pressure on 12 H.P. centre bearing at 4500 r.p.m. 1550 lb.in.sq. Maximum pressure on 12 H.P. outer bearing at 4500 r.p.m. 760 lb/in.sq. P.V. factor at 4500 r.p.m. on outer bear- ing with 79% balance. 29,900 P.V. factor at 4500 r.p.m. on centre bear- ing with 79% balance. 61,000 P.V. factor at 4500 r.p.m.on centre bear- ing with 90% balance. 55,000 P.V. factor on centre bearing with 79% balance at 3500 r.p.m. 28,700 P.V. factor on Bentley V bearing at 3500 rpm. 43,200 Maximum pressure due to gas load only on outer bearing 690 lb/in.sq. Maximum pressure due to gas load only on centre bearing 890 lb.in.sq. Maximum pressure due to gas load Bentley main bearing 1385 lb.in.sq. Cont'd.{John DeLooze - Company Secretary} | ||