Electromagnetic flowmeter is based on Faraday's law of electromagnetic induction for flow measurement, because of its own operating principle determines that it can measure conductive liquids, so it is widely used in sewage treatment, chemical industry and other fields.
But electromagnetic flowmeter due to the different manufacturing processes, not for the measurement of all media, the actual measurement in the field there will be many advantages and disadvantages.
Electromagnetic flowmeter advantages:
1. No pressure loss: due to the measurement tube without obstruction of flow parts, electromagnetic flowmeter will not cause additional pressure loss on the fluid
2. High-precision measurement: not affected by changes in fluid density, viscosity, temperature, pressure, in a certain conductivity range, high measurement accuracy.
3. Good corrosion resistance: different electrodes and lining materials can be selected, suitable for measuring a variety of corrosive media.
4. Suitable for complex fluids: especially suitable for measuring slurry containing solid particles, sewage and other liquid-solid two-phase fluids.
Disadvantages of electromagnetic flowmeter
1. Can not be used to measure the conductivity is very low or non-conductive liquid media, such as distilled water, petroleum products or organic solvents.
2. Can not measure non-conductive media: such as gas, steam, etc., is limited to the measurement of conductive liquids.
3. electromagnetic flowmeter used to measure viscous liquids with dirt, viscous material or sediment attached to the inner wall of the measuring tube or electrode, so that the transmitter output potential changes, bringing measurement errors, electrode on the dirt to reach a certain thickness, may lead to the instrument can not be measured.
4. due to the measurement of the pipe insulation lining material by the temperature limitations, the current industrial electromagnetic flowmeter can not measure high temperature and high pressure fluid.
Electromagnetic flowmeter has the advantages of high measurement accuracy, wide measurement range, almost unaffected by the physical properties of the fluid, reliable and durable and low maintenance. However, there are also sensitive to the wall thickness of the pipeline, affected by electromagnetic interference shadow, higher installation requirements, the fluid conductivity requirements and slow response speed and other shortcomings.