What are the effects of electromagnetic flowmeter on measuring mixed liquid?

Case introduction

The electromagnetic flowmeter is an intelligent flowmeter developed by our factory using advanced technology. It is very different from old-fashioned analog or non-intelligent electromagnetic flowmeters, especially in terms of measurement accuracy, reliability, stability, and usage functions. and service life, etc.

When larger particles in the slurry rub against the electrode surface, peak-like slurry noise will be generated in the electromagnetic flowmeter with low frequency rectangular excitation, making the flow signal unstable. , it is necessary to choose a higher frequency instrument or an instrument with a strong ability to suppress slurry noise. You can also choose an instrument with mains AC excitation or a dual-frequency excitation instrument. Our company's slurry electromagnetic flowmeter solves this problem very well.

Tiny bubbles mixed into the bubbly flow can still work normally, but the mixed volume flow rate containing the bubble volume is measured; if the gas content increases to form a bomb (block) Because the electrode may be covered by gas, the circuit may be instantly disconnected, causing the output to shake or even not work properly.

Solid-liquid two-phase fluids containing non-ferromagnetic particles or fibers can also measure the volumetric flow rate of the two phases. Fluids with high solid content, such as drilling mud, drilling cement slurry, paper pulp, etc., are actually non-Newtonian fluids. Since the solid flows together in the carrier liquid, there is sliding between the two and there is a difference in speed. If the single-phase liquid calibration instrument is used for solid-liquid two-phase fluid, additional errors will occur. Although there are no systematic experimental reports on the impact of solids in solid-liquid two-phase fluids using electromagnetic flowmeters, there are reports abroad that the error is within 3% when the solid content is 14%; my country's Yellow River Water Conservancy Commission Water Conservancy Research The institute's test report states that when measuring the flow of water with high sand content, the sand content volume ratio is 17% to 40% (sand median particle size is 0.35rnm), and the instrument measurement error is less than 3%.

Fluids containing ferromagnetic substances will cause measurement errors for ordinary electromagnetic flowmeters because the magnetic permeability in the measuring tube changes due to the different content of ferromagnetic substances. However, placing an electromagnetic flowmeter with a magnetic flux detection coil compensation in the magnetic circuit can reduce the impact of mixed ferromagnets. For slurry applications containing ore particles, attention should be paid to the degree of wear of the sensor lining. The expansion of the inner diameter of the measuring tube will produce additional errors. In this case, a ceramic lining or polyurethane rubber lining with better wear resistance should be used. It is also recommended that the sensor be installed on a vertical pipeline to make the pipeline wear evenly and eliminate the shortcomings of serious local wear in the lower half of the horizontal installation. You can also install a nozzle-shaped sheath at the inlet end of the sensor to extend the service life.

Supmea Co., Ltd. is a company specializing in the production of electromagnetic flowmeters, turbine flowmeters, vortex flowmeters, magnetic flap level gauges, thermocouples, thermal Resistors, bimetal thermometers, pressure gauges of various specifications, etc., as well as manufacturers of various non-standard flow meters. The company has advanced management levels, modern professional production equipment, and advanced calibration devices.