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).
Plans to test a low-carbon case-hardening steel as a cost-saving replacement for 5% nickel steel in various engine parts.
| Identifier | ExFiles\Box 142\2\ scan0387 | |
| Date | 22th December 1936 | |
| To HFS. Copy to Mr. EV.{Ivan Evernden - coachwork} Rm.{William Robotham - Chief Engineer} RAG. /JMR. 1200 E/PSN.3/MN.22.12.36. OKL Parts to be tested in Low Carbon Casehardening Steel. It has now been agreed to test out a low carbon case-hardening steel to replace 5% nickel steel for case-hardened parts in which a high core strength is not important. This change will result in a reduction in material cost for the parts concerned, of approximately 50%. The parts concerned on the 25/30 and Bentley should be tried out on as many experimental chassis as possible either with a view to gaining mass experience for early standardisation, or alternatively for gaining some experience for Wraith II which will start off with such parts in a low carbon steel. The Phantom III parts should also be tried out as extensively as possible with a view to getting such parts standardised with the four port head. The following is a list of parts on the Engine Section at present made in 5% nickel steel which should be tried out in a low carbon case-hardening steel. The specification of the steel should be fixed up with BY so that the tests are conducted on a material which would be acceptable for production. Bentley and 25/30. SIA E.50225. Roller pin. E.50226. Roller Tappet. E.55338. Tappet Guide Bush. EB.2590. Tappet Guide Cover. EB.2592. Tappet. EB.1114. Tappet Roller Balance Cam. EB.1117. Tappet Guide Balance Cam. EB.1115. Tappet Roller Pin. EB.1118. Tappet Balancing Cam. E.59700. Balancing Cam. E.54746. Crankshaft Pinion. EB.180. Starting Dog Cap. E.85333. Adjusting Screw (Tappets). E.60046/58. Adjusting Washers (Camshaft). E.58445. Dynamo Driving Gear. E.59947. Spindle Dynamo Drive. E.54765. Idler Wheel. E.54766. Spindle. EB.1123. Starting Handle dog. | ||