Flow meters are widely used in all fields of industrial and agricultural production, national defense construction, scientific research, foreign trade and people's daily life.
In the petroleum industry, from the exploitation, transportation and refining processing of petroleum to trade and sales, flow measurement runs through the whole process. Any link cannot do without flow meters. Otherwise it will be impossible to ensure the normal production and trade of the petroleum industry. In the chemical industry, inaccurate flow measurement will cause imbalance of chemical composition distribution ratio, unable to ensure product quality, serious cases may even lead to production safety accidents. In electric power industry, for liquid, gas, steam and other media flow measurement and regulation occupy an important position. Whether the flow measurement is accurate or not has great economic significance to ensure that the power plant operates under the best parameters. With the development of high temperature and pressure large capacity units, flow measurement has become an important part to ensure the safe operation of the power plant. For example, interruption or reduction of the instant water flow of a large capacity boiler may cause serious dry pot or burst pipe accidents. Therefore, the flow measurement device should not only be accurately measured, but also issue alarm signals in time. In steelmaking industry, the flow measurement of circulating water and oxygen (or air) in the steelmaking process is one of the important parameters to ensure product quality. In light industry, food, textile and other industries, flow measurement is also indispensable.