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).
The torque reversal test performed on model cranks DEB.2070 A & B.
| Identifier | ExFiles\Box 52\4\ Scan048 | |
| Date | 21th February 1934 | |
| To E. {Mr Elliott - Chief Engineer} From Hs {Lord Ernest Hives - Chair} /Bl. c. to By. {R.W. Bailey - Chief Engineer} c. to Rg. {Mr Rowledge} X 4499 Hs {Lord Ernest Hives - Chair} /Bl.2/KW.21.2.34. MODEL CRANKS - DEB.2070 A. {Mr Adams} & B. TORQUE REVERSAL TEST. The only difference between models "A" & "B" was that the crank pin bore in "B" was .050" eccentric - radially outwards relative to the journal centre line - to the crank pin. One of each type was subjected to a static torsion test, from which it was found that "A" was slightly stronger than "B". Four of each type were then subjected to a torque reversal or joggling test, the results of which are given on the attached chart. Although the ultimate times were not very consistent, "B" proved to be superior under these conditions. The fractures in each case were practically identical, commencing almost diametrically across the crank pin bore - at the lever end, opposite to the flywheel - eventually breaking through the crank pin towards the centre of the shaft as shown in the attached sketch. Hs {Lord Ernest Hives - Chair} /W.Bell. Print Attached. | ||