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).
Failures in the Condor engine's epicyclic gear, including broken bearings and bolts, and outlining plans for further testing.
| Identifier | ExFiles\Box 38\6\ Scan078 | |
| Date | 8th November 1918 | |
| X.3383 To R.{Sir Henry Royce} from EH. c. to CJ. c. to E.{Mr Elliott - Chief Engineer} c. to By.{R.W. Bailey - Chief Engineer} c. to Da.{Bernard Day - Chassis Design} EH2/LG8.11.18. RE CONDOR ENGINE. X.3254. X.3383. We find that the ball bearings in place of the roller bearings on the epicyclic gear are in very bad condition. Two of them are totally destroyed. The cages and all the balls have broken. From the discolouration due to heat, they have evidently been jammed and the inner races have been turned on the planet pinions. One bearing out of three is in good condition. The three ball bearings on the planet wheel end are in good condition. These bearings have run for 24 hours, 20 of which at 1800 r.p.m. 9/10ths. power = 540 HP. We also found one of the long bolts broken which retains the taper plugs in the planet gear ends. This is one of the original type bolts. We are replacing them with the latest type. There is also one of the springs broken in the spring drive in the gear. The friction plates show that a lot of movement has been taking place. The Ferodo discs are coming loose on the plates. From the appearance of the gear it has been working a long time with the ball bearings broken up. This may have had something to do with the spring breaking, and also we think it was the cause of the bolt shearing which bolts the steel housing to the case, which we reported on in our EH3/LG51118. We are running the 12-cylinder Condor fitted with the first large flywheel we made for the 2-cylinder. It is one which deflected on the 2-cylinder; on the 12-cylinder it runs quite truly. This flywheel would help to punish the gear. We are building the gear up again with the original roller bearings so as to be able to keep the engine running to test other parts. We shall have to dismantle the gear every 10 or 15 hours to see how they are going on. EH. | ||