Water Pump Power Calculator
Calculate Water Horsepower (WHP) and Brake Horsepower (BHP) for hydraulic systems.
Required Motor Power
20 HP
Understanding Pump Power Formulas
In the US imperial system, sizing a centrifugal pump requires calculating two main values: Water Horsepower (WHP), which is the theoretical power required to move the fluid, and Brake Horsepower (BHP), which is the actual power the motor must supply to overcome the pump's mechanical losses.
Water Horsepower (WHP):
$$ WHP = \frac{Q \times H \times SG}{3960} $$
Brake Horsepower (BHP):
$$ BHP = \frac{WHP}{\eta} $$
Where $Q$ = Flow in GPM, $H$ = Head in feet, $SG$ = Specific Gravity, and $\eta$ = Pump efficiency (decimal).