Pump Sizing
Pump Sizing
Pump Sizing
Prepare a sketch for the system in which the pump is installed including the upstream and downstream vessels
1. Sketch a diagram
6) Calculate differential pressure DP = Pdischarge P suction 7) Calculate power Hydraulic Power = Design Flow Rate X P 8) Estimated Power / Actual Horsepower = Hydraulic Power/Pump efficiency
NPSHA
For satisfactory pump operation the liquid must flow without vaporizing from the pump inlet to a point within the impeller eye where the vanes begin to impart energy to the liquid. The force tending to suppress cavitation is the margin by which the local static pressure of the liquid exceeds the liquid vapor pressure at that temperature. When converted to terms of head of liquid, this pressure margin is termed the net positive suction head, or NPSH. To avoid cavitation, the available net positive suction head (NPSH) must be greater than that required by the pump.
1. Sketch a diagram