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:
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.
Different flow rate to determine the diameter of the flow meter can meet the measurement range.
Different user environments.
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.
The performance and accuracy of the ultrasonic flowmeter are selected.
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.
Working principle and sensor parameters of ultrasonic external clamp flow meter
External clip type ultrasonic flow meter external clip type ultrasonic flow meter series measuring full flow of liquid flow meter, optional explosion-proof and intrinsically safe type, explosion-proof grade Exd[ib]IIBT6, and optional intrinsically safe remote control, explosion-proof grade ExibIIBT6, measurable medium: drinking water, river water, sea water, ground water cooling water, high temperature water, sewage, lubricating oil, diesel, fuel chemical liquid, other homogeneous fluid.
External clip sensor parameters:
The external clip type sensor is an installation method in which the sensor is directly bundled on the outer surface of the pipe to be measured to realize flow measurement, and has a diameter independent of the pipe diameter.
Simple installation, no need to stop production, no pressure loss and so on.
Ultrasonic flowmeter performance characteristics
Measuring liquid: single fluid such as water, seawater, alkali, etc., turbidity less than 10000ppm, particle size less than 1mm
Pipe material: Ultrasonic penetrating full pipe such as steel, cast iron, PVC pipe, dense texture, no serious corrosion and scaling, allowing thin layer of dense lining
Pipe lining material: rubber, epoxy asphalt, fiberglass, mortar, etc., or unlined
Pipe diameter range: DN15mm~6000mm, plug-in sensor for pipe diameter DN25mm~6000mm
Flow rate range: -32m/s~0~+32m/s, bidirectional flow
Accuracy: ±1.0% of displayed value (under standard conditions). Configure plug-in sensor accuracy up to 0.5%
Linearity: 0.5%.
Signal output: 4-20mA or 0-20mA RS-485
Sensor: It is divided into external clip type and plug-in type. The standard configuration is clip-on. The maximum operating pressure of the plug-in sensor is 3 MPa.
Straight pipe length: upstream >10D, downstream >5D from pump outlet >30D (D: pipe diameter)
Display mode: 2*20 character LCD display with LED backlight
Protection level: IP65
Explosion-proof grade: ExdIIBT4
Fixed ultrasonic flowmeter power supply: AC110V, AC220V, DC8~36V or AC7~30V
Ambient temperature / humidity: Host -20 ° C ~ +80 ° C; sensor -20 ° C ~ +80 ° C or -20 ° C ~ +160 ° C optional, the sensor can be immersed in water, water depth less than 2m.