The shortcomings of ultrasonic flowmeters are mainly that the temperature range of the measurable fluid is limited by the temperature resistance of the coupling material between the ultrasonic transducer and the transducer and the pipeline, and the raw data of the sound transmission velocity of the fluid under high temperature. Not complete. At present, China can only be used to measure fluids below 200 °C. In addition, the measurement line of the ultrasonic flow meter is more complicated than the general flow meter. This is because the flow rate of liquid in general industrial metering is often several meters per second, and the propagation speed of sound waves in liquid is about 1500 m/s. The change of flow velocity (flow rate) of the measured fluid brings the maximum change of sound velocity to 10- 3 orders of magnitude. If the accuracy of the measured flow rate is required to be ±1%, the accuracy of measuring the speed of sound needs to be on the order of 10-5 to 10-6, so a perfect measurement circuit must be implemented, which is the only way for the ultrasonic flowmeter to be integrated. The reason for the practical application can be obtained under the premise of rapid development of circuit technology.