Pump NPSH Calculator
kPa
kPa
kPa
kg/m³
NPSH Available
—
metres of liquid
NPSH Available (NPSHA) represents the suction head available above the liquid vapor pressure at the pump suction.
NPSHA =
[(Pa − Pv + Pn) × 1000]
÷ (ρ × g)
Where Pa is atmospheric pressure, Pv is vapor pressure, Pn is gauge pressure at pump suction, ρ is liquid density, and g = 9.80665 m/s².
To reduce the risk of cavitation, NPSH available should exceed the NPSH required by the pump with an appropriate margin.
This calculation assumes that the entered suction gauge pressure represents conditions at the pump suction.