Introduction to the principle and advantages of electromagnetic flowmeter

Electromagnetic flowmeter is an instrument that applies the principle of electromagnetic induction to measure the flow rate of conductive fluid based on the electromotive force induced when the conductive fluid passes through an external magnetic field.

Working principle:

Based on Faraday's law of electromagnetic induction, in the electromagnetic flowmeter, the conductive medium in the measuring tube is equivalent to the conductive metal rod in the Faraday test, and the two electromagnetic rods at the upper and lower ends The coil produces a constant magnetic field. When a conductive medium flows through, an induced voltage will be generated (the working principle is shown in the figure below). Two electrodes inside the pipe measure the induced voltage generated. The measuring pipeline is electromagnetically isolated from the fluid and measuring electrodes through a non-conductive lining (rubber, Teflon, etc.).

Advantages:

The measuring channel is a smooth straight tube that will not block and is suitable for measuring liquid-solid two-phase fluids containing solid particles, such as pulp, mud, sewage, etc.

There is no pressure loss caused by flow detection, and the energy saving effect is good.

The measured volume flow is actually not affected by the fluid density, viscosity, temperature, pressure and conductivity The obvious influence of changes.

Wide flow range and wide caliber range.

Corrosive fluids can be used first. Pay attention to the inspection of the appearance and check whether the appearance is damaged. The integrity of the appearance is the first priority of the electromagnetic flowmeter. Secondly, the accuracy inspection of the electromagnetic flowmeter is also the most important. Check the zero point of the electromagnetic flowmeter and pay attention to the zero point of the electromagnetic flowmeter. Calibration work must be carried out frequently to ensure the accuracy of the electromagnetic flowmeter. When inspecting the appearance, pay attention to the fact that the cable must be inspected thoroughly. The cable is where various signals are transmitted. Pay attention to the integrity and stability of the joints. At the same time, attention should also be paid to the penetration of impurities on the surface of the cable, and the cables should be packaged and protected as much as possible, especially for the interfaces. The degree of loss of the cables should be observed in a timely manner, and different cable models should be marked between different parts to prevent mistakes.