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 tensile testing of Quadrant Holders, proposing a material change from Silver Bronze to Dixstampo.
| Identifier | ExFiles\Box 148\2\ scan0105 | |
| Date | 31th December 1938 | |
| To BY.{R.W. Bailey - Chief Engineer} & Rm.{William Robotham - Chief Engineer} from RHC{R. H. Coverley - Production Engineer}/GTH.{G. T. Houlistan} 1260 RHC{R. H. Coverley - Production Engineer}/GTH.{G. T. Houlistan}1/LS.31.12.38. c. Hs.{Lord Ernest Hives - Chair} Da.{Bernard Day - Chassis Design} c. Cgh{W Clough}/EM. Handwritten: Gry{Shadwell Grylls} what are these pieces Rm{William Robotham - Chief Engineer} 1014 C RE QUADRANT HOLDERS. In view of the trouble experienced with cracks in the above pieces, it was suggested in RHC{R. H. Coverley - Production Engineer}/AK.1/AC.1.12.38., that these be produced in Dixstampo material instead of the present Silver Bronze. Some doubt existed, however, as to whether the Dixstampo pressings could be satisfactorily sweated to the mild steel tube and test pieces in Manganese Bronze and Dixstampo were, therefore, prepared for test purposes. The dimensions used, Fig.1., were representative of the actual control tube and holder, two sets of test pieces in each material being machined with .003 and .005 diametral clearance between tube and outer piece. The pieces were then sweated to the steel tube and subjected to a tensile test when it was found that the steel tube fractured on reaching a load of 3 tons as shown in Fig.1. the sweated joint remaining unaffected. In addition to being a more satisfactory stamping with negligible percentage of scrap, the quadrant holder produced in Dixstampo provides a saving of 2/6d per chassis over the present holder in Silver Bronze. No tool cost is involved since the existing dies can be utilised. In view of this, therefore, it is requested that future supplies of holders be instructed as Dixstampo Pressings, those for "C" series being instructed immediately. RHC{R. H. Coverley - Production Engineer}/G.T.Houliston. DIAGRAM TEXT: FIG.1 BORE .672 AND .674 +1/2 .500 DIA +-5 4.000 +-10 1.000 +-10 .750 +-25 STAYWAY CONTROL TUBE 18 S.W.G. S/D 2031B .669 DIA STEEL TUBE FRACTURE AT 3T TENSILE | ||