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).
Test report on the failure of an epicyclic gear's sun wheel carrier and testing of a low Stanton figure shaft.
| Identifier | ExFiles\Box 37\4\ scan 148 | |
| Date | 10th July 1917 | |
| X. 3045 To R.{Sir Henry Royce} from EH. c. to BJ. c. to E & Oy. c. to By.{R.W. Bailey - Chief Engineer} X.1445 - EPICYCLIC GEAR X.2909 On the engine, we are testing the new camshaft drive. We are also testing a standard epicyclic gear, the gear is fitted with a propeller shaft that had been condemned because of the low Stanton figure, the test piece only stood 440 blows. X.3045 The gear altogether has run 62 hours, 50 hours of this has been on 6 cylinders. The sun wheel carrier is now broken, it is broken in the usual place, that is, in the corner of one of the jaws for the blocks. This confirms our previous experience that the sun wheel carrier is the weakest unit on the gear, since we fitted the stronger propeller shafts. We think that the sun wheel carrier is the first part to fail because, there is a long period of time after it is fractured before it actually fails. One can feel something is wrong by the undue amount of slack in the gear. X.3045 Another reason of this test was, to try and confirm that a shaft with a low Stanton figure would fail quickly, as it happens the engine we were running this gear on, is also fitted with a crankshaft which was rejected because of the low Stanton figure. This crank has now run between 200 and 220 hours about half of this time it has run on 6 cylinders. Our experience on experimental tests do not confirm that a part with a low Stanton figure will not necessarily fail quickly. The epicyclic gear is being built up with a new sun wheel carrier and the engine will be run again. EH. | ||