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.
ltrasonic flowmeter installation
The time difference ultrasonic flowmeter is a competitive flow measurement method in the world today, and its measurement line accuracy is higher than 1.0%. Due to the diversity of the industrial site, especially the environment around the pipeline, how to install and debug the ultrasonic flowmeter according to the specific environment has become an important topic in the field of ultrasonic flow measurement. This procedure explains the installation details of the ultrasonic flowmeter; It further fully demonstrates the advantages of accuracy, reliability and stability of the ultrasonic flowmeter, greatly reducing future maintenance work and even maintenance-free.
Ultrasonic flowmeters should be aware of the site prior to installation, including:
1. What is the distance from the host at the installation of the sensor;
2. Pipe material, pipe wall thickness and pipe diameter;
3. Year of the pipeline;
4. Type of fluid, whether it contains impurities, bubbles, and whether it is full;
5. Fluid temperature
6. Whether there is interference source at the installation site (such as frequency conversion, strong magnetic field, etc.);
7. The temperature of the four seasons at the host site;
8. Whether the power supply voltage used is stable;
9. Whether remote signals and types are required;
According to the site conditions provided above, the manufacturer can configure the site conditions and, if necessary, special models.
Some experiences on using ultrasonic flowmeter
1. The flowmeter has two modes, diagonal and reflective. When the reflection mode is not detected, it can be measured in diagonal mode, so that we have been using the reflection mode.
2. The flowmeter requires a relatively high pipe, and the insulation layer must be scraped off, otherwise it cannot be measured. When we measured the air conditioning water system, we cut the insulation layer with a knife to prevent the sensor. After the measurement, the cut insulation layer was glued. The surface of the pipe should be as bright as possible. If it is too rough, it must be sanded.
3. It is difficult to measure when the fluid in the pipeline is not full, so the measuring position should be as straight as possible, away from elbows, valves and other places.
4. The authenticity of the flowmeter reading depends on the signal strength. When the signal is too low, the result is basically unreliable, generally more than 60% or even more.
5. Since the readings may vary greatly, the approach we take is to have the flowmeter read continuously, such as continuously recording one minute of reading and then taking the average.
6. Measuring hot water lines is more difficult than cold water lines. Because the wall temperature of the hot water pipe is high, the coupling agent is easily formed at a high temperature. In addition to the product's own coupling agent, we have tried toothpaste.
The summary of ultrasonic flowmeter measurement accuracy and accuracy needs to be improved.