Displacement water meter: installed in a pipe, consisting of a number of water meters that are successively filled and discharged by a known volume of fluid and a fluid actuated mechanism, or referred to as a quantitative discharge meter.
Velocity meter: a water meter enclosed in a closed pipe, consisting of a moving element, which is directly moved by the velocity of water flow to obtain power and speed.A typical speed water meter has a rotor type water meter and a spiral wing type water meter. There are single beam water meter and multi stream beam water meter in the rotor type water meter.
According to the medium temperature can be divided into cold water meter and hot water meter, the water temperature 30 degrees is its dividing line(1) a cold water meter: a water meter with a lower medium temperature of 0 DEG C and an upper temperature of 30 DEG C.(2) a hot water meter: a water meter with a lower limit of medium temperature of 30 DEG C and an upper limit of 90 DEG C or 130 DEG C or 180 DEG C.
