Water Distribution · Pumps and Pressure
What Does a Pump Curve Show?
A pump curve relates flow, head, efficiency, and power for a particular pump and speed. The actual operating point occurs where pump capability meets the resistance of the connected system.
Operators compare measured flow and differential pressure with speed, motor load, valve position, tank level, and the approved pump curve. Changing the system can move the operating point even when the pump is unchanged.
A pump does not deliver one fixed flow under every condition. Throttling, level changes, parallel pumps, worn components, or a changed main can shift both flow and power demand.
When flow falls while motor load changes, verify instruments and system conditions before declaring the impeller worn. A valve or pressure-zone change may have moved the operating point.
Key point: A pump's operating point is where its curve meets system resistance. The same pump can deliver different flows as the system changes.
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Water Distribution Fundamentals
This page comes from the course. It covers mains and valves, storage, pumps and pressure, water quality, backflow, main work and daily operations, one step at a time, with short knowledge checks and a certificate of completion.
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