Pump curves: a buyer’s guide to the information required
A pump curve is useful only when its reference conditions match the question being asked. Before comparing pumps or discussing performance, collect the curve identification and operating information. This guide explains the information to organize; it does not select or approve a pump for a duty.
Identify the curve
The Hydraulic Institute describes performance curves as showing relationships between flow and quantities such as head, efficiency, input power and required NPSH for a defined pump configuration. Record the model, speed and configuration shown on the supplied curve, together with its revision and source.
Collect the duty information
- Required flow and head, with units and the basis of those requirements.
- Fluid description, temperature and relevant properties supplied by the technical team.
- Operating range and whether demand varies.
- Available suction information and installation constraints.
- Driver, speed and power information where established.
Distinguish requested duty from observed operation
A design duty, a nameplate reference and a field measurement may describe different things. Label them separately. If the measured flow differs from the expected value, include the measurement method, operating condition and date rather than presenting the number without context.
Ask a focused technical question
Instead of asking whether a pump is “high efficiency”, ask the qualified reviewer to assess the specified duty and operating range against the applicable curve and equipment guidance. Ask what additional information is needed and which assumptions remain unresolved.
Questions buyers ask
Can the curve alone confirm suitability?
No. The actual system, fluid, installation and operating requirements also need review.
Does this website promise complete pump supply?
Current published scope centers on selected replacement components. Complete-pump enquiries require a separate capability assessment.
Related: suspected cavitation information and current component scope.
Technical reference
Hydraulic Institute Data Tool: Pump curves. Use the equipment manufacturer’s current documentation for the particular assembly.