Net Positive Suction Head Calculator

NPSH (Net Positive Suction Head) is a term referring to fluid supply in a pumping system. NPSH Required (NPSHR) is the amount of fluid that a pump will require at a certain operating point. NPSH Available (NPSHA) is the amount of fluid that a system can deliver to the pump. If NPSHR is greater then NPSHA, meaning the pump requires more fluid than is available to be pumped, the fluid will begin to cavitate and cause damage to the pump. This NPSH calculator is designed to calculate NPSH Available from a system. Fill in the fields below and press “Calculate” to see the results.

Note: In the case of calculating NPSHA for a reciprocating pump, this calculator does not include calculations for Acceleration Head. A pulsating flow on the supply of a reciprocating pump will affect the calculations below. Additional margin should be built into the calculation, as well as adequate pulsation control equipment installed on the suction side of the pump.

Site Information

Altitude {{data.altitude}} Select Unit

What type of fluid supply system do you have?

My pump is being supplied with fluid from an open tank

My pump is being supplied with fluid from a pipeline, pressurized tank, or another pump

{{supplyPressureLabel}}

{{data.supplyPressure}} Select Unit

Fluid Parameters

Flow Rate {{data.flowRate}} Select Unit

Liquid/Fluid Select Your Fluid

Fluid Temperature Select Fluid Temperature

Viscosity {{data.viscosity}} Select Unit

Specific Gravity {{data.specificGravity}}

Vapor Pressure {{data.vaporPressure}} Select Unit

Piping System

Pipe Length {{data.pipeLength}} Select Unit

Pipe ID {{data.pipeID}} Select Unit

Pipe Material Select Pipe Material

HZ Friction Coeff. {{data.hzFrictionCoeff}} Hazen William Coeff.

Roughness Height {{data.roughnessHeight}} Select Unit

Add Fitting

Fitting Type Qty

Select a Fitting Type {{fitting.Qty}} X

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