GB719020A - Pumping plant - Google Patents

Abstract

719,020. Centrifugal pumps. AKTIEBOLAGET FLYGTS PUMPAR, and ENGLESSON, S. Jan. 20, 1953, No. 1638/53. Class 110(1) A pump comprises two independently driven impellers mounted in a common housing having a single inlet and a single outlet only, a valve being provided at the junction of two branch passages connected to the impellers and being adapted, upon operation of -one impeller, automatically to close the branch passage connected to the other impeller. Casings 1, 2, Fig. 2, each containing a driving motor on the shaft of which is mounted an impeller, are each attached at a circumferential flange to parts 3, 4 respectively of a housing for the impellers. Branch passages 16, 17 and 8, 9, connect the impellers to an inlet 5 and a discharge 6 respectively. A ball valve 10, Fig. 3, at the discharge engages one of two seats 11, 11<SP>1</SP> when one impeller is operating to close the branch passage 8 or 9 connected to the inoperative impeller. Alternatively, two rigidly connected flap valves 13, 13<SP>1</SP>, Fig. 6, at the inlet engage one of two seats 15, 15<SP>1</SP> to close the branch passage 16 or 17 connected to the inoperative impeller. When both impellers are in operation, the valve or valves assume an intermediate position. The flap valves may be replaced by two ball valves. The impellers may be arranged at opposite sides of the impeller housing, with their shafts on a common axis.