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).
Allison's bearing production process and a visit to Gleason's concerning rear axle bevels.
| Identifier | ExFiles\Box 173\2\ img101 | |
| Date | 9th February 1934 guessed | |
| -2- Allisons do not centrifuge because they have been unsuccessful with this process of bearing production, and readily admit that it is the only satisfactory way of producing bearings of the Marine type, and with the knowledge we will obtain it will be helpful in improving the standard of our connecting rod bearings, without any infringement of the license for main bearings. During Allison's earlier attempts at the production of Marine type bearings, their scrap was 900 to 1000%, and the difficulty arose by first lining the inner surface with a separate operation for the outer diameter, and it was only possible by the normal casting process to produce bearings of this type by using a composition which was high in tin content for the external diameter, which enabled the casting of the 70/30 metal for the internal diameter to be carried out at a second operation. From the tests carried out, and judging by the performance of Allison bearings tested on their bearing test machine, it is obvious that the process is the solution to main bearing troubles. After casting of bearings they are quenched with a jet ring which pours the water on the outer diameter, and which must be directed at right angles to the wall of bearing in order to give the correct crystalline structure of material. as bearings pass thro the jet, it sinks into water tank below and is thoroughly quenched. Examination of a selection of bearings indicates the marked progress which has been made in the production of lead Bronze Bearings since the additional facilities of General Motors' Laboratories have been available, and I have arranged for samples of Derby produced bearings which were brought over to be sent to the GM Laboratories for micro-photographs to be taken in order to obtain comparative material structures with Allison's. Enclosed is a rough layout of the Allison bearing process and it will be observed that arrangements must be made for extractors to be placed over the crucibles during the casting of metal, in order to take away poisonous fumes which are given off. Further particulars of the process will be given later. GLEASONS: THURSDAY, FEB. 8TH. In response to a telephone request I visited Gleason's, Rochester, N. Y., in connection with the difficulty which had arisen over the production of 10/41 rear axle bevels. Gleason's explained in the first place that the mounting position for rear axle pinion was inaccurate to the extent of .080, and was not in accordance with Item No.17-18 for pinions, and Item No. 46 for gear wheels, given on the summary supplied by them. | ||