Because all kinds of ultrasonic flowmeters can be installed outside the pipe, non-contact flow measurement, the cost of the instrument is basically independent of the size of the pipe to be tested, while other types of flowmeters increase with the increase in caliber, so the cost is increased. The flowmeter is superior to the other functions of the same type of flowmeter. It is considered to be a good large-diameter flow measuring instrument. The Doppler ultrasonic flowmeter can measure the flow of two-phase medium, so it can be used for the measurement of dirty sewage such as sewers and sewage. In power plants, the use of portable ultrasonic flowmeters to measure large pipe diameters such as turbine water inflow and turbine circulating water is much more convenient than in the past. Ultrasonic flow juice can also be used for gas measurement. Pipe diameters range from 2cm to 5m, from a few meters wide open channels, culverts to 500m wide rivers.
In addition, the accuracy of the flow measurement of the ultrasonic measuring instrument is almost independent of the temperature, pressure, viscosity, density and other parameters of the measured fluid, and can be made into non-contact and portable measuring instruments, so it can solve the problem that other types of instruments are difficult to measure. Flow measurement problems for corrosive, non-conductive, radioactive, and flammable and explosive media. In addition, in view of the non-contact measurement characteristics, coupled with reasonable electronic circuits, one instrument can adapt to a variety of pipe diameter measurements and a variety of flow range measurements. The adaptability of ultrasonic flowmeters is also unmatched by other instruments. Ultrasonic flowmeters have some of the above advantages, so it has received more and more attention and has been developed into a series of products and generalization. It has been made into standard, high-temperature, explosion-proof and wet instruments of different channels to adapt to different media. Flow measurement for occasions and different pipeline conditions.
Intelligent GPRS MAG flow meter
The GPRS wireless transmission flowmeter is specially designed for the industry. It can meet the monitoring and management of traffic in urban water supply, heating and gas supply systems, and the processing and calculation of data. It is widely used in urban water supply, heating, gas supply systems, sewage treatment, Water conservancy projects and other industries.
GPRS wireless transmission flowmeter battery-powered converter is to use GPRS wireless communication to achieve remote monitoring. The data of the battery-powered converter can be read in any area covered by the GPRS wireless network. Through the GPRS wireless communication flowmeter network system, the data collected by the field instrument can be transmitted to the monitoring center in real time to achieve unified monitoring and distributed management of the field instrument.
GPRS wireless transmission flowmeter adopts specially designed sensor excitation system and high-performance lithium battery power supply system, and adopts 16-bit embedded ultra-micro power processor, full digital signal processing, stable measurement, high measurement accuracy and strong anti-interference ability. Features such as automatic bidirectional flow measurement, on-site instantaneous flow, positive and negativecumulative total display, self-diagnosis fault alarm, GSM data infinity transfer, etc. Users can realize traffic data through powerful GSM/GPRS remote management software system. GPRS wireless communication, storage, data analysis and other functions.
Second, choose from the type of flow meter
Various flow meters, such as volumetric flowmeters, speedmeters, and differential pressuremeters, have different characteristics. Different flowmeter types have different turndown ratios. The turbine flowmeter has a turndown ratio of 1:20 to 1:30, the Roots flowmeter has a turndown ratio of 1:20 to 1:160, and the film gauge has a turndown ratio of 1: 160 (The error characteristic curves of these three kinds of flow meters are shown in Figure 1), and the appropriate flow meter should be selected according to the actual situation.
By comparing the error characteristics of the above flowmeters, it can be seen that the starting flow of the membrane meter and the Roots flowmeter is small, the initial flow of the turbine meter is relatively large, and the membrane surface exhibits a positive deviation in the small flow state. The Roots flowmeter exhibits a negative deviation. At low flow rates, the gas supply company is more willing to select a membrane meter for metering.