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).
Examination report into a pivot pin failure on a Bentley Chassis for Mrs. Smith Bingham.
| Identifier | ExFiles\Box 88\1\ scan0119 | |
| Date | 17th December 1934 | |
| 7961 [Text crossed out: W.O.B. O.F.] C. Hs.{Lord Ernest Hives - Chair} BY.2/G.17.12.34. RE: BENTLEY CHASSIS. B.11.AE. MRS. SMITH BINGHAM. Referring to Sg.{Arthur F. Sidgreaves - MD}1/E.14.12.34. I have made a careful examination of the parts, and in addition Fm. arranged to dismantle a Bentley chassis which has done most in connection with brake judders to see if the pivot pins show any signs of failure. The examination of the experimental car demonstrated that the pivot pins were satisfactory, no cracks having started to develop. From my personal examination of the parts I can make the following report, although it cannot be considered conclusive as to what was the actual cause of the trouble :- (a). The fracture in the pin showed perfectly clear evidence indicating that the fracture had taken place due to fore and aft forces being exerted, on the pin. (b). The material of the pin was satisfactory, being quite up to our standard figures for 5% case hardening nickel steel. (c). There were certain points which might indicate that the car had had a severe bump in a fore and aft direction, if so this would have been undoubtedly contributory to the trouble. (d). The fractures had gradually developed over a period of time. From the appearance of the fractures it seems as if the upper part of the pin brake first, and following this the lower portion of the pin gradually fatigued through, but in both cases the fractures were of the fatigue type. Summarising I should say that it is difficult | ||