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).
Report from Ransome & Marles Bearing Co., Ltd. on the seventh test of a Hoffmann special bearing.
| Identifier | ExFiles\Box 114\2\ scan0034 | |
| Date | 6th April 1934 | |
| RANSOME & MARLES BEARING Co., Ltd. - 4 - Messrs. Rolls-Royce, Limited, D E R B Y . 6-4-34. SEVENTH TEST : A Hoffmann special bearing No. N.1421 was tested, this consisting of a full type roller for accommodating journal loads, and a duplex double purpose construction for the thrust load, the outside diameter of the outer thrust ring being undersize so as to ensure that this track would accommodate thrust load only. The loading conditions were identical with the conditions on the first test, and a continuous supply of Whitmore oil was provided, and after one hundred hours running, overload failure was found to have commenced. A resumé of the above tests indicates that our recommended method of mounting materially improves the serviceability of the job, while the modified bearing, having an angular contact more suitable for the duty still further improves the capacity of the bearing, and the use of a duralumin cage is most desirable. We are not altogether clear as regards the specific results of your road tests, and we should like to have these so as to have the complete history of the job, although the last test of 20,000 miles at which stage a slight overload failure had occurred indicates very clearly that the bearing in its present form with a duralumin cage will provide all that is necessary. We trust the foregoing is quite clear and shall be glad to modify these remarks should you so desire. Yours faithfully, RANSOME & MARLES BEARING CO. LTD. [Signature] MANAGING DIRECTOR. | ||