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 examination and status of 500 B.HP crank forgings, including a chemical analysis of the material.
Identifier | ExFiles\Box 38\6\ Scan009 | |
Date | 22th March 1918 | |
C O P Y. I have to report that I visited Coventry with Mr.Woods (D.A.I.) with a view to examining the 500 B.H.P. Crank Forgings from Messrs.Hyman & Gordon, and identifying same with their test reports and cast numbers. This examination was effected with the object of finding out whether the rejections were peculiar to any particular cast, and whether it was possible to continue work on crankshafts produced from any cast in which the rejections were apparently lower then others. The position is as follows:- 500 Shafts delivered to Messrs.Daimler. Finished machined and passed. (List A.{Mr Adams}).... 87) Scrapped for various defects including shop scrap. (List B.)...................... 102) at Messrs. Daimlers. Part machined.(List C.)..................... 122) In stock. (List D.{John DeLooze - Company Secretary}).......................... 32) Unaccounted for and in shops. (List E/).... 6) In process of machining(10 now accepted. (List G.{Mr Griffiths - Chief Accountant / Mr Gnapp})...................... 107) at Messrs. Siddeley & Deasy's. Scrapped,finished machined. (List F)....... 63) at Messrs. Siddeley & Deasy's. Returned to Daimler,scrapped finished machined. (List H)....................... 11 Total:- 550 It will be seen from the above figures that Messrs.Daimler have 154 shafts in stock, and the firm state that they will not continue further work on these shafts unless payment for machining is guaranteed by the Air Board. The whole of the 500 shafts appear to have been made from five casts, none of which can be considered satisfactory. The analysis of the various casts are as follows:- Cast No. 14990 15461 15449 15396 15450 Carbon .43 .56 .43 .42 .43 Manganese .76 .78 .56 .68 .78 Phosphorus .009 .011 .023 .033 .020 Sulphur .019 .043 .029 .026 .029 Nickel 3.04 3.42 3.02 3.46 3.14 Chromium .86 1.08 .95 1.03 .86 The analysis in my opinion is not suited for Crankshaft Stampings. The Carbon, Manganese, Nickel, and Chromium being all on the top side. | ||