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 concerning the shaft material, design, and alignment issues for a 40 HP Dynamometer.
| Identifier | ExFiles\Box 133\4\ scan0350 | |
| Date | 13th October 1936 | |
| EDWARDS X1126. LAURENCE, SCOTT & ELECTROMOTORS LTD ESTABLISHED 1883. NORWICH. SPECIALISTS IN D.C. AND A.C. ELECTRICAL MACHINERY AND CONTROL GEAR. WORKS & REGISTERED OFFICE—GOTHIC WORKS, NORWICH. "GOTHIC NORWICH" OR "1362 NORWICH." BRANCH WORKS—OPENSHAW, MANCHESTER. "MAGNET PHONE MANCHESTER" OR "0741 EAST." LONDON OFFICE—AUSTRALIA HOUSE, STRAND, W.C.2. "ORDERS ESTRAND LONDON" OR "2265 TEMPLE BAR." GLASGOW OFFICE—43, BLYTHSWOOD STREET, C.2. "OHMIC GLASGOW" OR "4394 CENTRAL." BIRMINGHAM OFFICE—72 JOHN BRIGHT STREET. "4211-2 MIDLAND." 13th October 1936 IMPORTANT PLEASE QUOTE IN REPLY 1128.35/ND1 YOUR REF. Messrs.Rolls Royce Ltd, DERBY. Dear Sirs, 40 HP Dynamometer No. 70093 Order No. 94504. Our Birmingham Office, in theirs of the 9th inst, wrote enquiring about shaft material for the above. We find that this was a hammered steel forging made from Siemens Martin Steel to British Standard specification No.29 and having a tensile strength of 35/40 tons. The shaft is exceedingly stiff and we see no particular object in making this of alloy steel having a higher tensile. The shaft is designed primarily to meet a criticial speed condition and not from the point of view of power transmission. This is apparently the shaft which according to Birmingham Office letter of the 17th August was found to be out of truth and we understood that this was due to the question of mal-alignment. Kindly note this is not a sleeve type armature. This design is impossible owing to the very high speed and to fit a new shaft would involve complete dismantling and re-winding of the armature. So long as the shaft is in line with E.J.J. HP | ||