Net positive suction head (NPSH)

Calculation of the available net positive suction head in pump suction lines

NPSH module

Program features:

Each pump has a specific NPSH_R. This is the minimum absolute pressure at the suction nozzle at which the pump can operate. To avoid pump cavitation, the NPSH_A of the system must be greater than the NPSH_R of the pump. In other words, the available NPSH must be higher than the required.

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NPSH_A is calculated using the following equation:

NPSH_A = H_p - H_vap + H_st - H_sf

where:

H_p	absolute system pressure at the surface of the liquid supply
H_vap	vapor pressure of the liquid at the pumping temperature
H_st	static height difference between the liquid supply surface and the established pump datum (usually the height of the pump impeller center line)
H_sf	all suction line losses including entrance losses, friction losses, valves, fittings etc.

all expressed in terms of liquid head at the pumping temperature (in meters)

Price: 150 EUR plus VAT

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