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The measurement principle of electromagnetic flowmeters is based on Faraday’s law of electromagnetic induction. The measuring tube of the flow meter is a short tube lined with a non-magnetic material. Two electrodes pass through the wall in the direction of the tube diameter and are fixed to the measurement tube. Its electrical connector is essentially level with the inner surface of the lining. When the excitation coil is magnetized by a bidirectional square wave pulse, a working magnetic field with a flux density of B is generated in a direction perpendicular to the axis of the measuring tube. At this time, if a liquid with a constant conductivity flows through the measuring tube, it will cut the magnetic field lines and induce an electromotive force E. The electromotive force E is proportional to the magnetic flux density B, which in turn is proportional to the product of the inner diameter d of the measurement tube and the average flow velocity V. The electromotive force E (flow signal) is detected electrically and sent via a cable to the converter. After amplifying the flow signal, the converter can display the fluid flow rate and output signals such as pulses and analog currents, which are used for controlling and regulating the flow. Electromagnetic flowmeter electrical materials and measurement media suitable for those materials: 316L stainless steel – Suitable media: domestic water, industrial water, raw water, municipal sewage; weakly corrosive liquids. HB Hastelloy B – Suitable media: non-oxidizing acids such as hydrochloric acid with a concentration of less than 10% ； Sodium hydroxide with a concentration of less than 50%, as well as ammonium hydroxide solutions with varying concentrations ； Phosphoric acid, organic acid ； Not suitable. HC Harnes C nitric acid. Suitable media: mixed acids, oxidizing salts, seawater ； Inappropriate. Titanium hydrochloride: Suitable media include seawater, various chlorides and hypochlorous hydrochlorides, organic acids, and sodium hydroxide/caustic soda. Titanium: Suitable media include various acids ； For chemical media other than hydrofluoric acid, fuming sulfuric acid, and alkalis, platinum is suitable for almost all acid, alkali, and salt solutions; however, it is not suitable for water or ammonium salts. As for the lining materials of electromagnetic flowmeters and the media for which these lining materials are suitable: Neoprene is suitable for water at temperatures below 80°C, as well as tap water and industrial water. Polyurethane rubber is suitable for pulp, slurry, and other substances at temperatures below 60°C, and it offers good wear resistance. Polytetrafluoroethylene F4 (PTFE): Media suitable for use at temperatures ranging from -10 to 120°C over the long term ； It has very stable chemical properties; it can be used to measure most acids, bases, sanitary fluids, and organic solutions. However, it is not suitable for use with KOH, nitric acid, or hydrofluoric acid. The suitable media for FEP (F46) are those for which the long-term operating temperature ranges from -40 to 80°C ； Its chemical properties are very stable. It can measure media containing a small amount of fine particles. The polyperfluoroalkoxy resin PFA is suitable for media whose long-term operating temperature ranges from -40 to 160°C ； It has very stable chemical properties, and it is possible to measure most acids and bases ； It is generally not used for measuring mud, coal slurry, ore slurry, etc. Ceramics: Suitable media for use where strength and resistance to deformation under temperature and pressure remain unchanged ； Suitable for viscous fluids and slurries containing solid particles. For more information, please visit the company’s official website at http://www.yb1518.com/. Please retain this link when reproducing the content! http://www.yb1518.com/UploadFiles/2012717174126829.jpg