Flow rate and head

The amount of fluid pumped by a water pump per unit time is called flow rate, while the flow rate of a centrifugal pump usually refers to the volumetric flow rate, which can be expressed in Q. The increase in energy obtained by a liquid under the action of unit gravity using a pump is called the head, which can be represented by the letter H in meters (m).

When selecting a water pump, the flow rate and head are the main parameters given by the design personnel based on the process calculation results, which are fixed values. In terms of the performance of the water pump itself, the flow rate and head often correspond within a certain range. When selecting a water pump, these two factors will affect each other. The ideal selection is for the fixed values required for industrial parameters to fall at the higher efficiency point of the water pump performance curve. In the event of deviation, it is necessary to comprehensively evaluate the adverse effects of the deviation and determine the selection result after weighing the pros and cons.