This calculator is used to size pumps. The calculator determines the total differential head of the pump and the absorbed power required. Frictional and static pressure drops in the suction and discharge lines are also calculated as well as the NPSH available.
Show Instructions
The calculator determines the total differential head and power required to pump a liquid from a source vessel through a line to a destination vessel.
Frictional and static pressure losses are determined for the suction side and discharge side of the pump. NPSH available, including a user specified margin if required, is also calculated.
 Enter the pump and vessel tag numbers
 Enter the barometric pressure at the pump
 Enter the margin over the basic NPSH available, if required
 Enter the pump efficiency
 Enter the fluid details and physical properties
 Enter the suction and discharge vessel gas pressures
 Set the suction vessel pressure to 0 barg if the pump is pumping from atmospheric pressure
 Set the discharge vessel pressure to 0 barg if the pump is pumping to atmospheric pressure
 Enter the suction and discharge static heads
 Choose the nominal diameter and schedule of the suction and discharge lines
 The calculator will determine the inside diameter of each line
 Enter a length for the suction and discharge lines
 Enter an absolute roughness for each pipe. Typical values:

 Commercial steel: 0.046 mm
 Drawn tubing (brass, lead, glass): 0.002 mm
 Asphalted cast iron: 0.122 mm
 Galvanized iron: 0.152 mm
 Cast iron: 0.259 mm
 Enter the quantities of each type of fitting for each pipe if known
 If the type and quantities of each fitting are unknown, enter a fitting factor. Typical factors for 50 metre long lines:
 3" diameter and smaller: 1.5
 4" and 6" diameter: 2.0
 8" diameter and larger: 2.5
 Enter a discharge control valve differential pressure if a control valve is fitted in the discharge line
 Click the "Calculate" button
 The calculator will determine the total differential pressure and power required to pump the specified fluid
 The NPSH available will also be calculated