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).
Tests on a Pathfinder pump focusing on the restriction of filter volume and smaller diameter pipe lines.
| Identifier | ExFiles\Box 106\2\ scan0098 | |
| Date | 30th June 1932 guessed | |
| LEQ. 3951 PATHFINDER PUMP TESTS. RESTRICTION OF FILTER VOLUME AND SMALLER DIAMETER PIPE LINE. The capacity of the filter used throughout the previous tests was found to be 31 cc's, and by filling up as much space as possible, this was eventually reduced to 14 cc's. The pump was set so that the fabrics gave the minimum clearance volume, and in order to avoid complications, this setting was not disturbed throughout the following tests. As a basis for comparison, tests were first taken with a 5/16" (standard) diam pipe 13' 3" long, and 3 way dashboard tap and an 80 cc filter in the suction system, and the other results computed as percentages of the figures, which were :- Initial Pumping Time (I.P.T.) at 20 R.P.M. = 17 1/2 secs. and delivery at 1750 R.P.M. = 133 lbs/Hr. 5/16" DIAM PIPE. The results showed that with the 5/16" diam pipe directly connected to the pump, the I.P.T. was reduced by 47%, the delivery at 1750 R.P.M. remaining practically unchanged. With the 14 cc filter added the I.P.T. was reduced by 27% and the delivery was unaltered. This seems to indicate that 20% of the I.P.T. was taken up by the extra large filter, capacity and a further 27% by the restiction of the filter elements. 1/4" DIAM PIPE. With a 1/4" diam pipe directly connected to the pump a reduction in I.P.T. of 65% was obtained without affecting the top delivery, whilst with the 14 cc filter attached the I.P.T. reduction measured 34% and still the same delivery at 1750 R.P.M. was obtained. | ||