Ultrasonic flowmeter is a kind of flow measuring instrument, the use of ultrasonic pulse in the flow through the two directions of the velocity difference, to find the flow of fluid, is a new type of ultrasonic flow meter successfully developed on the absorption of many advantages of ultrasonic flowmeters at home and abroad.
The ultrasonic flowmeter is based on the information of the flow velocity when the ultrasonic wave propagates in the flowing fluid, such as the propagation speed of the forward flow and the reverse flow due to the superposition of the fluid velocity. Therefore, the flow rate of the fluid can be detected by the received ultrasonic wave, which is converted into the flow rate. Ultrasonic flowmeter is composed of ultrasonic transducer, electronic circuit and flow display and accumulation system.
Ultrasonic flowmeter selection installation point must consider the following factors: full pipe, steady flow, scaling, temperature, pressure, interference and so on.
1, full pipe: Choose a pipe section filled with fluid material uniform quality, easy to ultrasonic transmission, such as vertical pipe section (fluid flow up) or horizontal pipe section.
2, steady flow: the installation distance should be selected upstream greater than 10 times the straight pipe diameter, downstream greater than 5 times the straight pipe diameter without any elbow, diameter reduction and other uniform straight pipe section, the installation point should be far away from the valve, pump, high voltage and frequency converter and other interference sources.
3, avoid the installation of external clamp-type ultrasonic flowmeter in the pipeline system at the highest point or free outlet vertical pipe (fluid flow down)
4, for open or not full pipes, the flow meter should be installed in the U-shaped pipe section.
5, the temperature and pressure of the installation point should be within the range that the sensor can work.
6, fully consider the scaling status of the inner wall of the pipe: although the selection of non-scaling pipe installation, if it can not meet, the scaling can be considered as the lining in order to better measurement accuracy
7, the two sensors of the external clamp ultrasonic flowmeter must be installed in the horizontal direction of the pipeline axial surface, and installed in the horizontal position of the axial surface within the range of ±45° to prevent the phenomenon of dissatisfied pipes, bubbles or precipitation on the upper part of the sensor to affect the normal measurement. If it cannot be installed horizontally and symmetrically due to the limitation of the installation site space, the ultrasonic flowmeter can install the sensor vertically or at an Angle under the condition that the upper part of the tube is free of bubbles.
Post time: Jul-14-2023