Ultrasonic flow meters enable users to perform flow measurement inspections at many points in the flow process without the need for permanent installation. This universal driving time timer has a dual-function button interface, an ergonomic handheld design, and a beautiful backlit color digital display that greatly simplifies setup and data collection. Compared with other traditional flowmeters or ultrasonic flowmeters, it has the characteristics of high accuracy, high reliability, high performance, and low cost. The flowmeter also has other advantages:
TVT technology design. Fewer hardware components, low-voltage broadband pulse transmission, and low power consumption.
Clear, user-friendly menu selections make the flowmeter easy to use.
Daily, monthly and yearly total traffic. The parallel operation of positive, negative, and net flow is displayed cumulatively by a scale factor (span) and a 7-digit number.
Ultrasonic flow meters have high metering accuracy, low maintenance and maintenance, and self-diagnostic functions, multi-channel ultrasonic flow meters are increasingly widely used in natural gas metering.
There are many factors affecting the incoming measurement of ultrasonic flow meter, such as flow meter upstream linear roughness, gas components, upstream straight pipe length, flow meter upstream fluid flow, noise interference, airflow pulsation, etc. For the operator, the most common is that noise in the pipe can interfere with the operation of the ultrasonic flowmeter, which in turn affects the performance of the instrument. The most typical generated part of this noise is places where pressure drop, such as a flow regulating valve.
At the beginning of the project, if engineer can recognize these influencing factors and take corresponding measures, it can reduce engineering costs, and once all equipment is installed, the problem is discovered and taken, generally pays high cost. Therefore, it is necessary to understand these measures to reduce noise effects, which can guide users to properly apply ultrasonic flow meters.
Noise is generated in the process of operation, such as high-speed gas through tubes, tubular members, protruding temperature sensors, regulating valves, and the like. The study found that the maximum noise is the large pressure drop regulation valve. If this noise is not handled, the signal detection system of the flowmeter will be interfered, and the transmission detection error is caused. The noise size and properties generated by the regulator valve are related to the design of the adjustment valve. Some adjustment valves are characteristic of "low noise", deliberately increase the noise frequency, but high frequencies reach the operating frequency range of digital ultrasonic flow meter, which seriously affects the normal operation of ultrasonic flow meters. Although the adjustment valve can reduce the noise signal by means of a cage design, the adjustment valve characteristic also determines that any valve with throttling characteristics is a potential ultrasonic noise source. Studies have shown that the energy loss of the valve body is proportional to the pressure of the pressure of the valve body and the actual working conditions, and the noise increases with the increase in the energy loss of the valve body.
Once the noise is generated, it will propagate upstream and downstream of the adjustment valve, so only the ultrasonic flowmeter is installed before the regulating valve does not guarantee the interference of the regulating valve noise. The experimental results show that the regulator is mounted downstream of the flowmeter, and the noise interference from the sensor adjacent to the regulation valve is 2 to 4 times the noise interference than the sensor from the regulating valve.