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The structure of an electromagnetic flowmeter mainly consists of a magnetic circuit system, a measurement conduit, electrodes, a housing, a lining, and a converter. Magnetic circuit system: Its function is to generate a uniform direct current or alternating current magnetic field. The DC magnetic circuit is implemented using permanent magnets, which have the advantage of a relatively simple structure and are less affected by alternating magnetic fields. However, they can cause polarization of the electrolyte liquid flowing through the measurement conduit, with positive ions surrounding the negative electrode and negative ions surrounding the positive electrode – that is, a polarization phenomenon of the electrodes. This leads to an increase in the internal resistance between the two electrodes, thereby severely affecting the proper operation of the instrument. When the pipe diameter is large, the permanent magnet is correspondingly large as well, which makes it bulky and uneconomical; therefore, electromagnetic flowmeters generally use an alternating magnetic field, generated by a 50Hz power supply. Measurement conduit: Its function is to allow the conductive liquid being measured to pass through. In order to divert or short-circuit the flux as the magnetic field lines pass through the measuring conduit, the conduit must be made of a material that is non-magnetic, has low electrical conductivity, low thermal conductivity, and sufficient mechanical strength; non-magnetic stainless steel, fiberglass, high-strength plastics, aluminum, etc., can be used for this purpose. Electrode: Its function is to lead out the induced potential signal that is proportional to the quantity being measured. The electrodes are generally made of non-magnetic stainless steel, and are required to be flush with the lining so as not to impede fluid flow. It should be installed vertically along the pipeline to prevent sediment from accumulating on it and affecting measurement accuracy. Shell: Made of ferromagnetic material, it serves as the enclosure for the excitation coil in the distribution system and protects it from interference from external magnetic fields. Lining: There is a complete electrically insulating lining on the inner side of the measuring conduit and on the flange sealing surface. It comes into direct contact with the liquid being measured, and its function is to enhance the corrosion resistance of the measurement catheter, preventing the induced electric potential from being short-circuited by the walls of the metal measurement catheter. The lining materials for electromagnetic flowmeters are often corrosion-resistant, high-temperature resistant, and wear-resistant materials such as polytetrafluoroethylene plastic and ceramics. Converter: The induced potential signal generated by fluid flow is extremely weak and highly susceptible to various interference factors. The function of the converter is to amplify this induced potential signal, convert it into a standard signal, and suppress the major interference signals. Its task is to amplify and convert the induced potential signal Ex detected by the electrode into a unified standard DC signal. For more information, please visit the company’s official website at http://www.yb1518.com/. Please keep this link when reproducing the content! http://www.yb1518.com/UploadFiles/2012717174126829.jpg