What is the volumetric water meter
A volumetric water meter, also known as a piston water meter, is a fixed-displacement water meter, which is defined as: installed in a closed pipe, consisting of a number of chambers of known volume that are successively filled and discharged with fluid and driven by fluid. A water meter composed of institutions.
1. Classification of volumetric water meters
Volumetric water meters are divided into two series: rotary piston type and disc type. When the water flow passes through the water meter, the water flow drives the piston (disc) to rotate (swing), and the volume of the piston cylinder (disc chamber) is constant. Therefore, the number of times the piston rotates (disc swings) is measured by the counting mechanism, namely The amount of water flowing through the meter can be known. In layman's terms, there are some small spaces (capacities) with constant volume inside the volumetric water meter. When the water flows through the water meter, these small spaces are first filled at the inlet end of the water meter, and then transferred to the outlet end of the water meter to be emptied. It is like "scooping" the water over by spoonfuls. Since the size of the "spoon" is constant and known, we only need to know how many spoons are scooped to know how much water has passed through.
2. Rotary piston volumetric water meter
The main products of volumetric water meters are rotary piston water meters. Disc-type water meters are rarely used in China, and only in a few countries such as the United States. Rotary piston water meters are generally small-caliber specifications, characterized by strong small flow measurement capability and high sensitivity (called C-level meters and D-level meters in the industry). At present, it is mainly used for the measurement of pure water in pipelines in China. The inner diameter of the water meter is generally 8mm, 15mm and 20mm. The repair and debugging of positive displacement water meters is more complicated.
The volumetric water meter has higher requirements on water quality and wears more than the rotor type water meter, so the engineering plastics used in the volumetric water meter are required to be more reliable in terms of hygiene and strength.
If the volumetric water meter encounters impurities in the flowing water, the piston or disc will be stuck, and the water supply will stop. The quality of water quality also directly affects the service life of volumetric water meters. With the use of time, due to the increase of the gap after wear and the increase of the leakage, the metering performance of the positive displacement water meter changes in a slow direction.
Except for the flow to the outside, there are no requirements for the installation orientation of the positive displacement water meter, the orientation of the reading dial, and the straight pipe section in front of and behind the meter.
3. Advantages and disadvantages of volumetric water meters
Compared with the rotor type water meter, the volumetric water meter has the advantages of strong small flow measurement capability and high sensitivity.
However, the volumetric water meter has high requirements for water quality, complex structure, difficult manufacturing and maintenance, and high cost, which affects its widespread use to a certain extent.