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).
Letter from Hoffmann Manufacturing Co. Ltd. regarding the supply and specifications of specially made bearings.
| Identifier | ExFiles\Box 94\2\ scan0096 | |
| Date | 3rd December 1936 | |
| HOFFMANN Registered Trade Mark 1620 BRANCHES: LONDON, BIRMINGHAM, MANCHESTER, LEEDS, GLASGOW. AGENTS IN PRINCIPAL COUNTRIES THROUGHOUT THE WORLD. TELEPHONE: 3151 (5 lines) TELEGRAMS: HOFFMANN. CHELMSFORD CODES USED: A.B.C. 5TH EDITION, BENTLEY PHRASE, BENTLEY 2ND PHRASE, MARCONI AND WESTERN UNION 5 LETTER BALL-AND-ROLLER-BEARINGS STEEL-BALLS-AND-ROLLERS THE HOFFMANN MANUFACTURING Co. LTD. CONTRACTORS TO THE ADMIRALTY, WAR OFFICE AND INDIA OFFICE. CHELMSFORD. MESSRS. ROLLS ROYCE, LIMITED, DERBY. Dec. 3rd 1936. YOUR REF. RM{William Robotham - Chief Engineer}/Gry.{Shadwell Grylls}8/R IN YOUR REPLY PLEASE QUOTE OUR REF. JHW/EH. 96171 A Dear Sirs, We thank you for your letter of the 30th November, reference as above, which has had our close attention. Regarding the third item, of your letter, this bearing will have to be made specially. As the end play is required to be a minimum, we will make this .0005"/.0015", which may be reduced when the bearing is mounted, owing to the expansion of the inner race. This bearing will be known as N. 2674, and is illustrated on the enclosed Drawing No. 41-473 L, Sec. 100. We do not recommend Duplex Bearings, except for those conditions where the thrust load is at all times greater than the journal load, on account of the possibility of four point contact which causes cage wear. However, as the life of the bearings is unimportant, the bearings we are supplying will be suitable for your experiment, and we are arranging to supply these as quickly as possible. We should be interested to know whether any of these bearings are required to specially fine limits. We thank you for your instructions, and assuring you of our best attention at all times, we remain, Yours faithfully, THE HOFFMANN MANUFACTURING CO. LTD. ENCLOSE. Drwg. 41-473 L, Sec. 100. | ||