Ultrasonic flowmeter uses the electronic principle to measure the flow meter. Although it has its own verification procedure, because it has the same usage management mode as the tap water industry measurement, it puts its performance requirements, measurement accuracy, verification cycle, etc. into the cold water meter. In the meantime, it has become more standardized. Since then, the use of large-caliber ultrasonic flowmeters has normative documents in the water industry.
Ultrasonic flowmeter (ultrasonic water meter) Because the measurement principle is different from electromagnetic water meter, its accuracy is different. How to choose an ultrasonic flowmeter with superior performance and precision:
1. The user flow range is used to determine the type, diameter, temperature, medium, etc. of the ultrasonic flowmeter, especially considering the common flow rate and the starting flow rate. The purpose is to ensure the water supply quantity, accurately measure and reduce the leakage rate. When using the water meter, the user's water meter Commonly used traffic generally cannot exceed the common flow value specified by the product.
2, different flow rate to determine the diameter of the flow meter can meet the measurement range.
3. Different user environments.
4. Also consider the working pressure, the structure of the flow certificate, the form of the converter (whether bidirectional flow, current, pulse, communication interface, data storage) and the length of the connecting cable.
5. The performance and accuracy of the ultrasonic flowmeter are selected.
6, users can learn more about the peers who are already using the ultrasonic flowmeter, to see the effect of their use, the accuracy of the measurement.
At present, industrial flow measurement generally has problems of large diameter, large flow, small diameter, small flow, high temperature liquid, and gas measurement. This is because the general flowmeter will bring manufacturing and transportation as the diameter of the measuring pipe increases. The difficulty of the above, the advantages of increased cost, increased energy loss, and inconvenient installation, ultrasonic flowmeters can be avoided. The German FLEXIM ultrasonic flowmeter measures diameters from 6mm to 6500 mm, from a few meters wide open channels, culverts to 500m wide rivers.
Electromagnetic flowmeter features
Using intelligent judgment, the measurement correction setting is not used, and the air traffic control alarm and electrode detection application are more convenient;
Advanced "rough error handling" technology, which can remove fluids such as slurry to measure sharp disturbances, reduce output runout, maintain high precision measurement and make output more stable;
With a fluid density setting, it can display mass flow;
Constant current excitation current range, 125mA, 250mA optional, can be used with different manufacturers, different types of electromagnetic flow sensors;
Control function with remote reset of the totalizer, with contact signal input for starting and stopping accumulation, suitable for total inspection and batch processing applications;
With self-test and self-diagnosis function;
Advanced non-volatile memory for higher circuit reliability and effective protection of setup and measurement parameters;
The meter can be equipped with an unpowered clock and memory for recording the power down time, power-on time and power-down time;
The meter has an optional hour recording function that can store flow and electrode resistance measurements for more than 30 days.
The new keyboard processing method avoids the keyboard operation affecting the measurement, and can enter and return the operation menu to make the parameter setting more convenient;
The total display uses 10-bit decimal 9999999999 full-value carry, which solves the practice of double-word full value 4294967285 (hexadecimal FFFF) carry-in habit;
With wireless transmission, the mesh network is organized by the wireless HART protocol.
Pipe flowmeter measurement method
Ultrasonic waves carry information about the fluid flow rate as they propagate through the flowing fluid. Therefore, the flow rate of the fluid can be detected by the received ultrasonic wave, and converted into a flow rate. According to the detection method, it can be divided into different types of ultrasonic flowmeters such as propagation velocity difference method, Doppler method, beam offset method, noise method and correlation method. Ultrasonic flowmeter is a kind of application that has been applied since the rapid development of integrated circuit technology in the past decade.
Non-contact instrument for measuring fluids that are difficult to access and observe, as well as large pipe runoff. It is linked to a water level gauge for flow measurement of open water flow. The use of ultrasonic flow rate does not change the flow state of the fluid without installing the measuring element in the fluid, and does not generate additional resistance. The installation and maintenance of the instrument can not affect the operation of the production pipeline and is an ideal energy-saving flowmeter.
As we all know, industrial flow measurement generally has the problem of large diameter and large flow measurement difficulty. This is because the general flowmeter will bring difficulties in manufacturing and transportation with the increase of the measuring pipe diameter, and the cost will increase and the energy loss will increase. Installation is not only a disadvantage, but ultrasonic flowmeters can be avoided.