What are the unqualified phenomena when using sewage electromagnetic flowmeter?

Case introduction

The electromagnetic flowmeter is an intelligent flowmeter developed by Haynes Instruments with the introduction of advanced technology. It is very different from the old analog or non-intelligent electromagnetic flowmeters, especially in terms of measurement accuracy, reliability, stability, Functionality and service life.

The measurement accuracy of the sewage electromagnetic flowmeter is never affected by changes in fluid density, viscosity, temperature, pressure and conductivity. The sensor induced voltage signal has a linear relationship with the average flow rate, so its measurement accuracy high. Because the induced voltage signal is formed in the entire magnetic field-filled space and is the average value on the pipe cross-section, the straight pipe section required by the sensor is relatively short, with a length of 5 times the pipe diameter. There are no flow obstructions in the flow meter measurement pipe, so there is no additional pressure loss. There are no moving parts in the measurement pipe, so the life of the flow sensor is relatively long. Electromagnetic flowmeter is a flow meter with high precision, high reliability and the longest service life. Every link in the process of product structure design, material selection, process formulation, production assembly and factory testing is very meticulous. . The sensor part of the electromagnetic flowmeter is lined and the electrodes are in contact with the liquid to be measured. As long as the appropriate electrode and lining materials are selected, it can resist corrosion and wear. Sometimes the flowmeter selection is not suitable for the working conditions of the medium being measured on site or is affected and restricted by the process flow, and the technical installation requirements of the electromagnetic flowmeter are not met when installing the electromagnetic flowmeter.

There are length requirements for the straight pipe sections at the inlet and outlet of the sewage type electromagnetic flowmeter. There are reducers connected before and after the flow sensor. If you want to align the straight pipes, there are some, which must fit the length of the inlet and outlet of the electromagnetic flow sensor. The pipe's gradually expanding or tapering cone angle is required to be less than 15°. Considering the cost of constructing a water meter set proposed to the water supply center and the need for straight pipes for electromagnetic flowmeters that would make the water meters too long and narrow, we can consider choosing electromagnetic flowmeters with primary or secondary diameters. The water flow velocity is within the specified range. It can be calculated based on the size of the reducer within the specified range. It will not impose any requirements on the flow meter. If you want to customize a non-standard gradually expanding or reducing tube, it can be lengthened. A certain length of reducer will reduce the intermediate cone angle to within the taper requirement. The result is that the flow rate in the electromagnetic flowmeter is partially increased, which meets the demand for the surface flow rate range. After removing the attached scale on the measuring sensor of the electromagnetic flowmeter, the re-certification will be qualified. If the operator understands the characteristics of the measurement medium and the structural performance of the electromagnetic flowmeter, and performs targeted maintenance, the intelligent electromagnetic flow rate can be achieved. The design can better maintain higher quality.

The installation location of the sewage type electromagnetic flowmeter sensor is too close to the pump room. When the pumps are working at the same time, the vibration will be too large, which will affect the stable working condition of the flowmeter. After moving the sensor away from the vibration source, the situation will return to normal. Sometimes it is because there are more debris in the measurement medium, especially in the presence of hard or corrosive debris such as sand. , it will aggravate the wear and tear of the flow meter.damage and corrosion. As a result, the error of the electromagnetic flowmeter increases without taking preventive measures. These factors, acting alone or together, will worsen the performance of the flowmeter and cause it to fail during calibration. Part of the reason for the failure of electromagnetic flowmeters is that the on-site management personnel have not received targeted training, are not very clear about the flowmeter management structure and principles, and do not perform routine maintenance well. For example, a factory's sewage treatment plant sent an electromagnetic flowmeter for inspection, and the test was found to be unqualified. After inspection, it was found that a layer of attachments accumulated on the inner wall of the electromagnetic flowmeter sensor. Because the conductivity of the attachment layer is different from the conductivity of the medium, the The flow meter is not working properly.

Supmea Automation Instrument 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 and various other products. 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.