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 to The S.U. Co. regarding issues with returned pumps, specifically roller diameters and weak springs.
| Identifier | ExFiles\Box 149\6\ scan0043 | |
| Date | 24th September 1937 | |
| 1263 24th September 1937 Rm{William Robotham - Chief Engineer}/JBD.{John B. Dixon - Fuel Systems}10/AP. The S.U.Co., Bordesley Green Road, Adderley Park, BIRMINGHAM.8. For the attention of Mr.Leslie Kent. Dear Sirs, We thank you for your letter of the 21st. inst., referring to the examination of the two pumps we returned to you. With regard to the rollers which we stated were below .429" diameter, these would not pass through your ring gauge as the diameter is not below the .429" limit all the way round and a ring gauge would only pass a roller if the roller was truly round and the diameter down. We are sending you a few more examples of this trouble together with one Bentley pump and one H.P. pump. In the first the spring is weak in one unit and in the other we have built up two weak H.P. units found in two separate pumps. The weak spring causes a falling off in delivery which is very noticeable as the pressure is increased. We feel that if each unit is only tested for flow with practically no head against it the trouble does not become apparent. With a pressure head of five feet of paraffin the difference between a normal unit and the ones returned is 20 pts. per hour and will show a considerable difference in the maximum speed for which one unit alone will supply the engine when the trial switch is used. On the high pressure pump pot, is there any reason why the vent hole should not be drilled at the lowest point of the pot (i.e.) in line with the bottom hole.? We are anxious to do this so that if at any time water should get into the unit it would have a betterchance of being blown out. | ||