Measurement difference management is an important work in the gas fluid calculation. Firstly, the measuring principle of the ultrasonic flowmeter is introduced, and the measuring range, installation requirements, and fault detection of the ultrasonic flowmeter are described and studied. At the same time, in order to obtain better overall maintenance and use of the effect of the flowmeter, we should fully understand the relevant issues in the actual use process and provide some reference for its application in the industry. At present, there are three types of gas flow meters commonly used in industrial production and trade calculation, namely ultrasonic flow meter, turbine flow meter, and orifice flow meter. The specific introduction of the three products is as follows.

1. Turbine Flowmeter

The rotation rate of the turbine flowmeter varies with the flow rate. Generally, the higher the velocity is, the greater the kinetic energy is, and the higher the turbine speed is. Therefore, it is actually a flowmeter based on the principle of velocity difference. In the application process, it is necessary to convert the flow rate into turbine speed first, and then obtain the corresponding electromagnetic pulse. Finally, the flow information can be obtained based on the obtained pulse number. The application advantages of the gas flowmeter are large flow and high accuracy. However, it is easily to be affected by impurities, reducing the reliability of its application.

2. Orifice Flowmeter

In terms of structure, the orifice flowmeter is mainly divided into a flow indicator and a throttling device. The specific principle of the flowmeter is that there is a proportional relationship between gas flow and differential pressure. As long as the differential pressure before and after the orifice is measured, the medium flow information can be analyzed. The application advantages of this flowmeter are reflected in its high cost-performance ratio, long service life, simple operation, etc., and it is widely used in the actual production field. But it has many disadvantages, such as low repeatability, narrow measuring range, large pressure loss, etc. In the process of use, there will be large measurement errors caused by corrosion, wear, oil contamination, and pressure loss.

3. Ultrasonic Flowmeter

The ultrasonic flowmeter is a fluid flow measuring instrument designed according to the principle of time-difference method, which adopts advanced multi-pulse technology and signals digital processing technology. The installation method of the ultrasonic flowmeter is a non-contact installation and measurement, which has the advantages of no need to contact the measured fluid and a low possibility of generating an open fire. In addition, it has strong adaptability to the environment of various industrial sites, so this flowmeter has become the most suitable and most popular measuring instrument in the current gas flow measurement.