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).
Stress testing a standard crankshaft to failure by towing a car.
| Identifier | ExFiles\Box 74\3\ scan0303 | |
| Date | 23th December 1924 | |
| R.R. 493A (50H) (D.B. 175 25-9-24) J.H.D. -3- EXPERIMENTAL REPORT. Expl. No. REF: Hs{Lord Ernest Hives - Chair}/TMW/LG23.12.24. when running in top gear. It was then decided to endeavour to break a standard Crankshaft by the same means as it was suspected caused the disc crankshaft to break - i.e., the car being towed in 1st. gear, throttle closed, on the worst vibratory period. 6-G-11 was used for this purpose and the speed was 20 to 21 m.p.h. The shaft eventually broke but probably twice the running was necessary; the break was in the same place viz - No.6. crank pin, but at the front throw instead of the rear. As a proof that more punishment was necessary to break the standard shaft, it can be mentioned that 3 of the 4 driven pins of the spring drive (E.52478) had sheared off under the head and the drive generally showed distinct signs of distress, whereas the spring drive was O.K. after the disc shaft had broken. Hs{Lord Ernest Hives - Chair}/TMW. | ||