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 reliability of electric flash-butt welding for Bentley III and Bentley 50 models, including test results.
| Identifier | ExFiles\Box 148\5\ scan0347 | |
| Date | 2nd March 1938 | |
| COPY. To BY.{R.W. Bailey - Chief Engineer} from HPS.{Horace Percy Smith - Experimental Factory Mgr} c. RHC.{R. H. Coverley - Production Engineer} HPS.{Horace Percy Smith - Experimental Factory Mgr}2/VS.{J. Vickers}2.3.38. ELECTRIC WELDING. In view of the reduction in manufacturing costs which are obtainable by the use of flash-butt welding, we are anxious to incorporate this method of fabrication where possible on Bentley III and Bentley 50, and in order that the reliability of welds made by this process may be fully appreciated we have submitted a number of mild steel test pieces to the Laboratory, who report as follows :- Maximum Stress. Yield Point. Elongation % Red. Area % Brinell. 40.9 30.6 17.5 42.7 170 40.6 29.7 15.0 41.9 170 40.4 29.5 15.0 37.8 179 39.4 29.5 26.5 57.4 179 The above were welded and subsequently heat-treated. 35.6 25.3 24.5 56.8 149 35.6 25.1 24.0 57.4 146 35.5 24.9 23.5 57.4 149 35.3 25.0 25.0 57.9 149 The above were welded and received no subsequent heat-treatment. From these figures it will be seen that the maximum stress is almost 100% of that of the original material, and whilst the elongation is somewhat reduced this is not to such an extent as will materially affect the safety of the welded construction. We have previously submitted to you a pedal plate flash welded to the shaft which, when tested to destruction, proved stronger than the standard component, and we shall therefore be glad if you will consider standardising this process continued. | ||