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 Stothert & Pitt regarding the trial and specifications of a rotary displacement pump.
| Identifier | ExFiles\Box 149\2\ scan0032 | |
| Date | 18th June 1930 | |
| X3449. STOTHERT & PITT, LTD. ENGINEERS. HEAD OFFICE & WORKS: BATH. LONDON OFFICE 38, VICTORIA ST.{Capt. P. R. Strong}, S.W. Telegrams: STOTHERT SOWEST LONDON. PHONE No 1849 VICTORIA, LONDON. TITAN FOR BUILDING HARBOURS Telegrams: STOTHERT BATH. PHONE No BATH 2277 (4 LINES) REFERENCES: OURS: GS/MC. YOURS: F.4706. BATH. 18th June 1930. Messrs. Rolls-Royce Ltd., Derby. Dear Sirs, We beg to confirm the conversation between Mr. Robotham and our Mr. Kemp at your Works on June 13th in connection with the size 1 rotary displacement pump which we supplied to you for purposes of trial in July 1928 by arrangement with Mr. Elliott. We understand that you have not actually made trials with this pump, and shall be glad to hear if you are likely to use it in the near future. The pump supplied has an inner rotating member of 3 lobes meshing with an outer rotor of 4 lobes, and a later development covered by the same patent comprises an inner rotor of 7 lobes meshing with an outer rotor of 8 lobes. This later design is used particularly for forced lubrication, running at a higher speed than the original pattern, and we think it would fulfil your requirements, as the pulsations are practically negligible and the pump is very quiet in operation, whilst giving a high volumetric efficiency. As an example, it has been used with success on the duty of crosshead lubrication for Sulzer diesel engines where the pressure rises to about 360 lbs. per sq. in. Perhaps you will be kind enough to inform us if this design is of any interest to you, and if desired we shall be pleased to supply you with a small pump for purposes of trial. Mr. Kemp has given us a note of your requirements in the shape of a petrol pump for aircraft, but although we have had considerable experience in petrol pumps for larger outputs, we regret that we have no design which is likely to satisfactorily fulfil the duty you describe. Yours faithfully, For STOTHERT & PITT LTD. S. Tundalwich Manager Pump Dept. | ||