Rolls-Royce Archives
         « Prev  Box Series  Next »        

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.
  
  
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).


Copyright Sustain 2026, All Rights Reserved.    whatever is rightly done, however humble, is noble
An unhandled error has occurred. Reload 🗙