Provisions on the service life of water meters

According to the relevant provisions of the Metrology Verification Regulation of the General Administration of Quality Supervision, Inspection and Quarantine:

The service life of water meters with a diameter of 1, 25mm or less is generally less than 6 years;

2. The service life of water meters with a diameter greater than 25mm to 50mm is generally not more than 4 years;

3、? Industrial water meters should be tested regularly, and domestic water meters should only be tested for the first time, and should be rotated when they expire.

Extended data

Water meter is an instrument for measuring water flow, mostly the cumulative flow of water. Generally divided into two types: volumetric water meter and speed water meter. It originated in Britain and has a history of nearly 200 years. When choosing the specifications of water meters, we should first estimate the size and range of the flow used under normal circumstances, and then choose the most common flow as the first choice.

Grading by measurement

According to the old standard, it can be divided into class A table, class B table, class C table and class D table.

The metering grade reflects the working flow range of the water meter, especially the metering performance under small flow. According to the order from low to high, it is generally divided into Class A, Class B, Class C and Class D, and its metrological performance meets the corresponding requirements of Class A, B, C and D metrological grades stipulated by national standards.

After the release of the new standard, the classification method of measurement grade becomes quite complicated, which is mainly determined according to various parameters such as flow value and range ratio. Simply put, the larger the measurement range, the higher the measurement level.

Divided by nominal caliber

Divided into large-caliber water meters and small-caliber water meters.

According to the nominal caliber, it is usually divided into small caliber water meters and large caliber water meters.

Water meters with a nominal diameter of 50mm and below are usually called small-caliber water meters, and water meters with a nominal diameter of 50mm and above are called large-caliber water meters. These two kinds of water meters are sometimes called civil water meters and industrial water meters. At the same time, this method can also be different from the case connection form of water meter. The water meters with nominal 50mm and below are connected by thread, and the water meters with nominal 50mm and above are connected by flange. But some special types of water meters also have 40 mm flange connections.

References:

Baidu encyclopedia-water meter