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As one of the commonly used measuring instruments in industry, the electromagnetic flowmeter can effectively measure and determine the data you need. At the same time, the measurement accuracy class and functions of electromagnetic flowmeters can be selected based on the measurement requirements and application scenarios, thereby ensuring true cost-effectiveness. For applications such as trade settlement, product transfer, and energy measurement, it is advisable to choose a higher precision grade, such as 1.0 grade, 0.5 grade, or even higher grades. In cases of process control, different precision grades should be selected based on the control requirements. For situations where only the process flow needs to be measured, without the need for precise control or measurement, a lower precision grade can be used, such as 1.5 grade, 2.5 grade, or even 4.0 grade. The electromagnetic flowmeter series are all excellent tools for measurement in industries such as manufacturing and agriculture; you can choose one based on your specific needs. 1. Measurement of liquids containing bubbles by electromagnetic flowmeters: The flowmeter can still function properly even when there are tiny bubbles present in the flow, but the value measured is the volumetric flow rate of the mixture, including the volume of those bubbles ； If the gas content increases to the point where a slug flow is formed, the electrodes may be covered by the gas, causing the circuit to be interrupted momentarily; this can result in fluctuations in the output or even prevent normal operation. 2. Electromagnetic flowmeters for measuring liquid in solid-liquid two-phase flows. The volumetric flow rate of the two phases can also be determined for solid-liquid two-phase fluids containing non-ferromagnetic particles or fibers. Fluids with a high solid content, such as drilling mud, drilling cement slurry, and pulp, are actually non-Newtonian fluids. Since the solids flow together with the carrier fluid, there is sliding between them and a difference in speeds; therefore, instruments calibrated for single-phase fluids will introduce additional errors when used with solid-liquid two-phase flows. Foreign reports indicate that when the solid content is 14%, the error remains within 3% ； According to the test reports from the Institute of Water Resources Science under China’s Yellow River Water Resources Commission, when measuring the flow rate of water with high sediment content, the volume fraction of sediment ranges from 17% to 40% (with an average particle size of sand of 0.35 mm), and the measurement error of the instruments is less than 3%. When larger particles in the slurry scrape against the electrode surface, sharp slurry noise is generated in electromagnetic flowmeters with low-frequency rectangular excitation, causing instability in the flow signal. In such cases, it is necessary to use instruments with higher frequencies or those capable of effectively suppressing slurry noise; alternatively, instruments powered by AC mains or those with dual-frequency excitation can also be used. 3. Measurement of liquids containing ferromagnetic substances by electromagnetic flowmeters Fluids containing ferromagnetic substances can cause measurement errors in conventional electromagnetic flowmeters, as the magnetic permeability inside the measuring tube changes depending on the amount of ferromagnets present. However, there is an electromagnetic flowmeter EMF with a flux detection coil placed in the magnetic circuit to compensate, which can reduce the influence of ferromagnetic materials that may be present. Test reports show that when using a slurry in water containing iron ore with a liquid-to-solid weight ratio of approximately 4:1 and a particle size of ≤ 0.15 mm, and conducting flow rate comparison tests between clean water and this slurry using a gauge with an 80 mm diameter orifice, the reading variation of conventional gauges is between 7% and 10%; whereas gauges equipped with flux detection coils have a reading error within ±2% of Fs. 4. Measurement of slurry using electromagnetic flowmeters When using these meters for slurries containing ore particles, attention must be paid to the degree of wear on the sensor lining; an increase in the inner diameter of the measurement tube can cause additional errors. For such applications, ceramic linings or polyurethane rubber linings with good wear resistance should be used. It is also recommended to install the sensors on vertical pipes, so as to ensure even wear across the pipe and eliminate the problem of severe localized wear in the lower part when the pipe is installed horizontally. A nozzle-shaped shield can also be installed at the sensor inlet to relatively extend its service life. 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