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Pump Formulas:

PressurePsi = (HeadFt X Specific Gravity) / 2.31

HeadFt = (PressurePsi X 2.31) / Specific Gravity

VacuumIn Hg = Dynamic Suction LiftFt. X .883 X Specific Gravity

Brake HP = (GPM X HeadFt. X Specific Gravity) / (3,960 X Pump Efficiency)

Motor KW = (GPM X HFt. X Specific Gravity X 0.746) / (3,960 X Pump Eff. X Motor Eff.)

Affinity Laws:

Impeller Diameter Change: GPM2 = D2/D1 X GPM1

H2 = (D2/D1)2 X H1

BHP2 = (D2 / D1)3 X BHP1

Speed Change:
GPM2 = RPM2/RPM1 X GPM1

H2 = (RPM2/RPM1)2 X H1

BHP2 = (RPM2/RPM1)3 X BHP1



























GPM = Flow rate in gallons per minute
H = Head in feet
BHP = Brake Horsepower
D = Impeller diameter
RPM = Pump speed in revolutions per minute

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