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The key to the measurement stability of electromagnetic flowmeter is the introduction of the meter.

The meter head is the key to the metering stability of the electromagnetic flowmeter. Coils, measuring tubes, electrodes, linings and gauges are the main components of electromagnetic flowmeters.
Electromagnetic flowmeter coil: Its function is to produce a uniform DC or AC magnetic field. The DC magnetic circuit is realized by a permanent magnet, which has the advantages of simple structure and less interference by the alternating magnetic field, but it is easy to polarize the electrolyte liquid in the measuring duct, so that the positive electrode is surrounded by negative ions, and the negative electrode is positive ion Surrounding, that is, the polarization phenomenon of the electrode, and causing an increase in internal resistance between the two electrodes, thus seriously affecting the normal operation of the meter. When the diameter of the pipe is large, the permanent magnets are correspondingly large, bulky and uneconomical, so the electromagnetic flowmeter generally adopts an alternating magnetic field and is generated by the excitation of a 50HZ power frequency power source.
Electromagnetic flowmeter measuring catheter: In order to make the magnetic flux be shunted or short-circuited when the magnetic flux passes through the measuring catheter, the measuring catheter must be made of non-magnetic, low electrical conductivity, low thermal conductivity and mechanical strength. Generally, stainless steel and carbon are used. steel.
Electromagnetic flowmeter electrode: Its function is to draw and measure the induced potential signal proportional to it. The electrodes are typically made of non-magnetically conductive stainless steel and are required to be flush with the liner so that the fluid passes without obstruction. It should be installed in the vertical direction of the pipe to prevent deposits from accumulating on it and affecting the measurement accuracy.
Electromagnetic flowmeter lining: A complete electrical insulation lining on the inside of the measuring tube and on the flange sealing surface. It directly contacts the liquid to be measured, and its function is to increase the corrosion resistance of the measuring catheter and prevent the induced potential from being short-circuited by the metal measuring tube wall. Most of the lining materials are PTFE plastics and ceramics that are resistant to corrosion, high temperature and wear.
Electromagnetic flow meter head: The induced potential signal generated by the liquid flow of the medium is very weak and is greatly affected by various interference factors. The function of the electromagnetic meter is to amplify and convert the induced potential signal into a unified standard signal and suppress the main interference. signal. Since the meter head converts the induced potential signal (Ex) detected by the electrode into a standard DC signal, the meter head is the key to the metering stability of the electromagnetic flowmeter.

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