Since ancient times, flow measurement is a sign of human civilization. Egyptians use the Nile River flow meter to predict the harvest is good or bad. Roman drainage pipes and water, measured by orifice flow. However, because of economic production, the end of this century, 50's, the main industrial use only orifice flow meter, pitot tube, rotameter of three. Narrow range of measured medium, the measurement accuracy can only meet the low level of production. After World War II, with the international economy and the rapid development of science and technology, growing emphasis on flow measurement, flow meter subsequently developed rapidly. To meet the different types of fluid properties, flow under different flow measurement problems, the past 30 years, has developed and put into the meter with speed meter, volume meter, momentum flow meter, electromagnetic flow meters, ultrasonic flow of dollars and dozens of new types of flow meters.
 

Flow meters currently in use abroad has more than 100 kinds of domestic production of stereotypes is also nearly 20 species. With the automation of industrial production, pipeline of development, flow meter instrument in the growing share of production. According to data shows that, in different industrial sectors, the flow meter used in the total 15-30% of the total instrument. With the rapid development of flow meters, flow device has also developed rapidly, flow, money transfer network has been formed. Currently the water, oil, gas, steam high accuracy flow device at the national, provincial and municipal agencies measure to ensure accurate and consistent flow of money transfer.
    However, due to complicated flow measurement technology, as well as the rapid development of science and technology, flow measurement made to higher requirements, the status of flow measurement can not meet the production needs of a large number of flow measurement technology issues to be further studied solution. The main purpose of the following problems:
Flow meter type, specifications, accuracy and reliability can not meet production requirements. Particularly corrosive fluids, dirty fluids, high viscosity fluids, multiphase fluid, large flow, small flow rate, pending the development of effective means of measurement.
Flow meter standard equipment can not meet the test requirements, in particular, on-site verification real fluid flow meter standard equipment, is in our present circumstances pressing problem.