Water meters are divided into speed water meters and volume water meters according to the measurement principle.
(1) Velocity water meter: a water meter installed in a closed pipeline, composed of a moving element, and directly obtained by the speed of the water flow.
Typical speed water meters include rotary-wing water meters and screw-wing water meters. There are single-stream water meters and multi-stream water meters in rotary-wing water meters.
(2) Volumetric water meter: Installed in the pipeline, a water meter composed of a number of chambers of known volume that are filled and discharged with fluid successively and a mechanism driven by the fluid, or quantitative discharge water meter for short.
Volumetric water meters generally adopt a piston structure.
