OPTIMUM LOCATION OF SUCTION AND DISCHARGE TAPPINGS IN CENTRIFUGAL PUMP TESTS

摘要

Tests have been made on a 6 inch pump (Ns = 2900 approx) and a 4 inch pimp (Ns = 950 approx) to study the effects of the location of the suction and discharge tappings on the measured pump characteristic.nThe tests on the 6 inch pump showed that at discharges below one half normal, considerable pre-whirl was induced in the suction pipe and measurements of pressure at the suction flange were in error by amounts up to 13% of the total head, which was sufficient to change the actually stable characteristic to an apparently unstable one. The magnitude of the pre-whirl error was found to be dependent on impeller design.