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).
Test results for varying pipe diameters and filter capacities on pumping performance.
| Identifier | ExFiles\Box 106\2\ scan0099 | |
| Date | 30th June 1932 guessed | |
| -2- Contd. When the 30 cc filter, and dash-tap were fitted with ¼" diam pipe throughout, the I.P.T. reduction from standard was 45%, showing a capacity loss of 25%, and a filter element restriction of 15%. 3/16" DIAM PIPE. A still further reduction in the pipe diam was made, and tested with the 14 cc filter in the line, and although the I.P.T. was reduced by 70%, a reduction in the delivery at 1750 R.P.M. of approximately 30% (the actual delivery being 90 pts/hr) was obtained, therefore no further tests were taken. DELIVERIES UP TO 2000 R.P.M. - PUMP SPEED. Delivery curves up to 2000 R.P.M., were obtained:- (a) With 3/16" diam pipe, 20 cc filter and 3 way tap. (b) With ¼" diam pipe, 20 cc filter and 3 way stop. (c) With ¼" " a 14 cc ". Throughout the speed range there was very little to choose between the three curves. Therefore the reduction of both pipe diam, and filter capacity produced a decrease in the slow speed pumping without affecting the higher speed deliveries. The following figures show the actual times and deliveries recorded under standard conditions (i.e. 3/16" pipe and 20 cc filter), and the best conditions available for chassis purposes (i.e. ¼" pipe and 14 cc filter) :- (a) 3/16" PIPE AND 20 cc FILTER. INITIAL PUMPING TIME AT 20 PUMP R.P.M. 2 MIN 53 SECS " " " 30 " " 1 " 33 " DELIVERY AT 1750 RPM 133 PTS/HR. (b) ¼" PIPE AND 14 cc FILTER. INITIAL PUMP TIME AT 20 PUMP RPM. 1 MIN 20 SECS " " " 30 " " " 35 " | ||