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).
Investigation into the failure of Borg & Beck eyebolts and discussions on strengthening them.
| Identifier | ExFiles\Box 129\3\ scan0085 | |
| Date | 5th February 1936 | |
| -2- Ha/Smth.10/KM.5.2.36. Borg & Beck roll the threads on their eyebolts. Under the microscope the threads appear to have a very poor profile and show folding over of the metal in several places. The eyebolts are made of 30 ton material. We have had a clutch assembled using eyebolts in S/THOR with turned threads. This has already run for 40 hours on the bed without failure, which is more than twice as long as the best known life of the old bolts. It has been agreed by By.{R.W. Bailey - Chief Engineer} that we should return all Borg & Beck clutches in the Works at present for refitting with these strengthened bolts. We have taken up with Borg & Beck the question of enlarging the dia. of the eyebolts at the threaded end, but they are strongly against this because the necessarily larger hole in the cover would weaken this piece to a considerable extent. We are continuing our investigations of the cause of the failures. Hs{Lord Ernest Hives - Chair}/F.W.LL.Smith. | ||