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).
Material composition analysis of Spectre valve seats, identifying a discrepancy and suggesting the material is Silicon Monel Metal.
| Identifier | ExFiles\Box 150\1\ scan0053 | |
| Date | 11th October 1935 | |
| Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} BY/EM.37/J.11.10.35. SPECTRECodename for Phantom III VALVE SEATS. We are in receipt of your memo Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer}13/KW.1.10.35, in regard to the above together with a copy of a letter from Mr.Banks in regard to material used for this purpose in France. It is obvious that the information conveyed by Mr.Banks is not complete as according to the analysis the total ingredients only amount to 90% and therefore, it is obvious that a further 10% of something has been omitted from his figures. We think it is most probably the nickel content should read 70% instead of 60% as stated. If we are correct in this assumption, then the material is obviously that known as Silicon Monel Metal, but if this is the case, we consider that their figures quoted for the co-efficient of expansion are very optimistic and we should not imagine they are actually more than .000016. We shall be glad if you could obtain confirmation of the figures from Mr.Banks and if our surmise is correct and it is Silicon Monel which is being used, then we can easily obtain supplies in this country either from Messrs. Henry Wiggin & Co, of Birmingham or the Sheepbridge Stokes Centrifugal Castings Co, Limited. BY EM for B | ||