The magnetic inductive flowmeter has a wide range of applications. Large diameter meters are more often used in water supply and drainage projects. Small and medium caliber instruments are commonly used in solid-liquid biphasic and other difficult to measure fluids or high requirements, such as measurement of paper industry pulp and black liquor, non-ferrous metallurgy slurry, coal slurry, chemical industry, strong corrosive liquids, and iron and steel industry, blast furnace cooling water control and monitoring leakage of long-distance pipelines, coal hydraulic conveying flow measurement and control. Small diameter, tiny caliber commonly used in the pharmaceutical industry, food industry, biological engineering and other places with health requirements.
Advantages and Disadvantages of Magnetic Inductive Flowmeter
Advantages of Magnetic Inductive Flowmeter
(1) The measuring channel of the magnetic inductive flowmeter is a smooth straight pipe without flow-blocking detectors. Because it is not easy to block. Suitable for measuring liquid-solid two-phase fluid containing solid particles or fibers. Such as pulp, coal water slurry, slurry, mud and sewage.
(2) Electromagnetic flowmeter does not produce pressure loss due to the formation of the detection of flow. The resistance of the meter is only the resistance along the same length of pipe. Energy saving effect is remarkable. For the requirements of low resistance loss of large diameter water supply pipeline is most suitable.
(3) The volume flow rate measured by the electromagnetic flowmeter. Practically unaffected by the obvious changes in fluid density, viscosity, temperature, pressure and conductivity.
(4) Compared with most other flow meters. Front straight pipe section requirements are lower.
(5) electromagnetic flowmeter measuring range is large. Usually 20:1 ~ 50:1. optional flow range is wide. Full-scale liquid flow rate can be (0.5 ~ 10) m / s selected. Some models of meters can be expanded and reduced in the field according to the needs of the flow.
Disadvantages of Magnetic Inductive Flowmeter
(1) Electromagnetic flowmeter can not measure the liquid with very low conductivity. Such as petroleum products and organic solvents. Can not measure gas, steam and liquids containing more large bubbles.
(2) general-purpose magnetic inductive flowmeter due to the limitations of the lining materials and electrical insulation materials. Can not be used for higher-temperature liquids; some models of instruments used for measurement of liquids below room temperature. Will be due to condensation outside the measuring tube (or frost) and damage the insulation.
Magnetic Inductive Flowmeter Selection Considerations
- Application areas
Large diameter meters are mostly used in water supply and drainage projects. Medium and small diameter meters are often used in solid-liquid two-phase and other difficult to measure fluids or high-demand places. Such as measuring the paper industry pulp liquid and black liquid, non-ferrous metallurgical industry slurry, coal slurry, chemical industry, strong corrosive liquid and iron and steel industry blast furnace wind mouth cold but the water control and monitoring leakage. Flow measurement and control of hydraulic transportation of coal in long-distance pipelines. Small caliber and micro caliber instruments are commonly used in the pharmaceutical industry, food industry, biological engineering and other places with sanitary requirements.
- Accuracy level and function
The performance of general-purpose magnetic inductive flowmeter has a big difference. Accuracy of the instrument basic error ± 0.2 rs or ± 0.5% RS; multi-function meter has a measurement of two-way flow, range switching, upper and lower limit flow alarm, empty pipe and power cut off alarm, small signal cut off, flow display and total amount of calculations, automatic verification and self-diagnosis of faults, and so on.
- Flow rate, full-scale flow rate, range and caliber
electromagnetic flowmeter full-scale flow rate when the liquid flow rate can be (0.2 ~ 10) m / s range of options. Electromagnetic flowmeter caliber from 6mm ~ 2200mm range. Electromagnetic flowmeter caliber selection is not necessarily the same as the diameter of the pipe, specific should be based on the flow of the most range combined with the selection of samples to determine.
- Conductivity of the measured medium
electromagnetic flowmeter to measure the fluid must be electrically conductive, generally as long as the conductivity exceeds the threshold, even if the change does not affect the measured value, but below the threshold will increase the measurement error; usually requires the liquid conductivity is not less than 5 μS/cm, deionized water conductivity is not less than 20 μS/cm.
- Temperature of the measured medium
magnetic inductive magnetic inductive flowmeter can only be used for process media temperature is not higher than 180 ℃ occasions. Selection, according to the measured temperature range of the process medium, select the measuring tube lining material and sensor coil enameled wire temperature rating.
- The liquid contains mixed substances
mixed into the bubble flow of tiny bubbles can still work properly. However, the measured volume is the mixed volume flow rate with the volume of gas bubbles; such as the gas content increases to the formation of popping (block) flow. Because the electrode may be covered by the gas to make the circuit instantaneous disconnection. Output shaking or even can not work properly.
