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).
Cylinder bore wear, materials like Chromidium iron, and Brinell hardness for 25/30 and Bentley cylinder blocks.
| Identifier | ExFiles\Box 86\1\ scan0242 | |
| Date | 29th May 1937 | |
| Hs.{Lord Ernest Hives - Chair} from Rm.{William Robotham - Chief Engineer} c. E.{Mr Elliott - Chief Engineer} c. Ey. c. REC. c. HI. Rm{William Robotham - Chief Engineer}6/R.29.5.37. 25/30 & BENTLEY CYLINDER BLOCKS. Further to Rm{William Robotham - Chief Engineer}1/R.26.5.37., we have now read By.10/G.25.5.37. and Ey.14/G.25.5.37. In view of the remarks contained therein, we rang up Taub of Vauxhall's, who is acknowledged to be one of the foremost experts in the world on cylinder bore wear. He has been running tests on Chromidium iron made by the Midland Cylinder people and has compared it with other irons. We did not tell him of our results, but asked what he thought of Chromidium. He said that, in his opinion, it was neither better nor worse for wear than the Buick cylinder iron. We pointed out that some of the English cars with Chromidium cylinder blocks suffered from bad wear. He said that this was due to the design of the engine unit, and not the fault of the material. Taub's one criticism of Chromidium was that in his high production output it occasionally had hard spots which produced machining difficulties. CYLINDER BORE. We attach wear figures covering French and English conditions, which, briefly analysed convey the following information:- (a) Between 2-300 brinell there seems to be little difference between cylinder bore wear in either French or English conditions. (b) In the case of the P.III where we have an opportunity of having liners with brinell as high as 360, we appear to be getting slightly better wear from the very much harder liners, but this is only to the order of 10%. Summarising, therefore, the present position seems to be as follows:- In an endeavour to get a high brinell we are running about 50% scrap in the Factory. We have no evidence | ||