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).
Static and vibration test report on Bentley 50 rear axle couplings, comparing a standard taper and a Barber-Colman taper spline.
| Identifier | ExFiles\Box 111\4\ scan0079 | |
| Date | 28th October 1938 | |
| 802. To Hm.{Capt. W. Hallam - Head Repairs} from HPS{Horace Percy Smith - Experimental Factory Mgr}/W.Bell. c.c. to By.{R.W. Bailey - Chief Engineer} c.c. to Dav. c.c. to Hdy.{William Hardy} c. to Rm{William Robotham - Chief Engineer}/PJH. PJH HPS{Horace Percy Smith - Experimental Factory Mgr}/WB.{Mr Brazier/Mr Bell}5/CB.28.10.38. BENTLEY 50 REAR AXLE COUPLING TESTS. Tests were carried out with :- (1) Rolls-Royce Standard taper and Woodruff key. (2) Barber-Colman taper splines. The same taper was used on the Rolls-Royce type as that supplied by Barber-Colman - i.e. 1 in 6.5. Two tests were carried out on each type. A.{Mr Adams} Static Test. To permit relative movement between the parts to occur, the key was deleted from the R.R. type and the Barber-Colman serrations were reduced in width by .125". - This did not affect the area of contact of the mating tapers. The locking nut on the end of the shaft was tightened up with a torque of 200 lb. ft. and then the torque necessary to cause initial slip between the surfaces was found. B. Vibration Test. A calibrated torsion shaft with a R.R. coupling at one end (The key being in position) and a Barber-Colman coupling (with full width serrations) at the other end was subjected to a Torque Reversal Test. The frequency of oscillation of 320/min. was constant throughout the test, the torque being increased at intervals up to a maximum of 600 lb. ft. The total running time was made up by :- 110 hrs. at 50 lb. ft. (Reversals 4,224,000) 60 " " 112 " " ( " 2,304,000) 100 " " 225 " " ( " 3,840,000) 60 " " 600 " " ( " 2,304,000) Total 330 (Reversals 12,672,000) continued. | ||