The development of measurement can be traced  to Ancient water conservancy projects and urban water supply systems. The Guromache has used the orifice plate to measure the drinking water quantity of the residents. In the 1000 BC, Ancient Egypt used Weir method to measure the flow of the Nile River. China's famous Dujiangyan Water Conservancy project Application Treasure Bottle water level observation water size and so on.
Metrology is the eye of industrial production. Flowmeter is one of the components of metrology science and technology, it has close relationship with national economy, national defense construction and scientific research. Doing well in this work has an important effect on guaranteeing product quality, improving production efficiency and promoting the development of science and technology, especially in the current era of energy crisis and increasing automation degree of industrial production, and the position and function of flowmeter in national economy is more obvious. Flowmeter is divided into differential pressure flowmeter, rotor flowmeter, throttle type flowmeter, fine slit flowmeter, volumetric flowmeter, electromagnetic flowmeter, ultrasonic flowmeter and Weir. Classification by medium: liquid flowmeter and gas flowmeter.