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).
Endurance test report on a F.II petrol pump, focusing on a loosening pivot pin issue.
| Identifier | ExFiles\Box 17\5\ Scan112 | |
| Date | 21th March 1932 | |
| 87460. R.{Sir Henry Royce} From Hs{Lord Ernest Hives - Chair}/Sl. a.{Mr Adams} to Hs.{Lord Ernest Hives - Chair} Wor.{Arthur Wormald - General Works Manager} b. to S. Ds. c. to Hy.{Tom Haldenby - Plant Engineer} Hs{Lord Ernest Hives - Chair}/Al.1/1A. 21. 3. 32. Lec. 2951 F.II PETROL PUMP. ENDURANCE TEST - 500 HOURS LIMIT. It was observed during the previous delivery tests with this type of pump that the tappet lever pivot, or fulcrum pin P.S2503 tended to loosen where it was riveted into the support plate. The pin was re-riveted, and an endurance run made using the pump and operating mechanism specified in the above scheme, except for the pump head. Having transferred the correct head (integral inlet air bottle type) to another pump, and there being no more available at the time, an Lec. 2937 head was fitted. Driven by a constant speed electric motor at 1500 R.P.M., the rig was run for 22 hours per day. The delivery and maximum pressure were measured at the commencement of the run and checked at 50 hour intervals, the figures being recorded :- Total Time Hours. 0 50 100 150 200 250 300 350 400 450 470.15 Delivery. Gls/Hr. 106 103 103 103 97 75 74 76 72 66 65 Max: Press: lb/sq.in. 4.25 2.1 2.45 2.1 2.25 2.1 0.5 1.0 1.0 1.0 1.0 The redesigned pivot pin - Lec. 2936 - being available, the test was stopped after 470 hrs. 15 ins., since the original pivot pin was quite loose, with the result that the effective plunger stroke was diminished, thus producing the reduced deliveries, and pressure recorded in the above table. Before recommencing the test, the pump was stripped and examined. Due to the slackening of the pivot pin, the hole in the support plate was .007" oversize, also the flange and rivet head had cut into the faces of the plate. It was also observed that there was a fine crack in the fillet, between the flange and the stem of the pin; this was probably started by the riveting. | ||