Equipment reference

Pump selection

Build a selection brief that connects the liquid, system duty and installation. The result is a documented configuration and operating range, not a model name alone.

← All pump topics Calculate hydraulic power

Required inputs

State normal, minimum and maximum flow and head; fluid composition, temperature, viscosity and solids; inlet level or pressure; running hours and control method. Keep unknown values visible and identify who will confirm them.

Hydraulic power estimate

Estimate the power transferred to a liquid at a known flow rate and total pump head. Enter the liquid density for your operating conditions.

Pₕ = ρ × g × Q × H. The calculation converts flow to m³/s and uses g = 9.81 m/s². Power is shown in W and kW.

For a steady liquid flow with representative density. This estimate does not select a pump or calculate shaft power, electrical input, efficiency, cavitation margin or a pump curve.

Hydraulic power estimate. Pump model selection is not included.

Topic for the local draft

Opening another topic does not change your explicit choice. This topic labels the draft; it does not confirm a pump type or model.

Use a decimal point or comma without thousands separators. All values must be greater than zero.

Flow rate Q

Flow unit

Total pump head H, m

Use the total head the pump must add to the liquid. Outlet pressure or elevation alone is not the total pump head.

Liquid density ρ, kg/m³

Use the density at the stated liquid composition and temperature. No water density is assumed.

Local draft format

Choose a topic and calculate first. The draft stays on this page and is not sent or submitted.

Checks on the curve

Use the exact speed, impeller diameter and fluid basis. Check duty range, efficiency, absorbed power and motor allowance, minimum flow, NPSH margin and pressure limits. Correct water curves for other fluids only through a justified method or manufacturer selection.

Here, absorbed power means mechanical power required at the pump shaft. Electrical input also includes motor and drive losses. NPSHA is the installation’s available suction head above vapour pressure; compare it with the pump’s stated NPSHR and the specified margin.

Installation and interfaces

Add connection standard and size, envelope and removal space, permitted orientation, supply voltage and frequency, controls, protection and ambient conditions. For replacement include nameplate, serial number, photos, drawing revision and the actual measured duty.

Selection result and supply

Request an identifiable configuration, duty-point curves, material and seal schedule, motor data, drawing, control scope and document list. Record catalogue-standard and individually trimmed selections separately. Price, lead time, warranty and acceptance tests must refer to the same configuration.