Measurement principle and installation method of split electromagnetic flowmeter

The measurement principle of the split electromagnetic flowmeter is based on Faraday's law of electromagnetic induction. The split electromagnetic flowmeter consists of a sensor and a converter. The sensor is installed on the measuring pipe, and the converter is installed within 30 meters or 100 meters from the sensor. The two are connected by a shielded signal cable. The main components of the sensor are: measuring tube, electrode, excitation coil, iron core and yoke housing. The split electromagnetic flowmeter is mainly used to measure the volume flow of conductive liquids and slurries in closed pipes. Such as water, sewage, mud, pulp, various acids, alkalis, salt solutions, food slurries, etc., are widely used in petroleum, chemical, metallurgy, textile, food, pharmaceutical, papermaking and other industries as well as environmental protection, municipal management, water conservancy construction and other fields to measure high temperature, high humidity, and inconvenient observation environments.

The installation position of the split electromagnetic flowmeter should be far away from the disturbance source that can cause mechanical vibration of the pipeline, such as the pump on the technical pipeline. If the split electromagnetic flowmeter is used in series on the same pipeline, the mutual influence caused by resonance should be avoided. The distance between the split electromagnetic flowmeters should be at least three times greater than the width of the split electromagnetic flowmeter's overall dimensions. If installed near the expansion joint, the elasticity of the pipeline will cause lateral stress, causing the zero point of the split electromagnetic flowmeter to change, affecting the measurement accuracy. The installation position of the split electromagnetic flowmeter should pay attention to the elasticity and deformation of the technical pipeline caused by temperature changes, and it should not be installed near the expansion joint of the technical pipeline.

The installation position of the split electromagnetic flowmeter should be far away from industrial electromagnetic interference sources, such as high-power motors, transformers , etc. Otherwise, the self-resonant vibration of the measuring tube in the split electromagnetic flowmeter will be disturbed, and the weak signal detected by the split electromagnetic flowmeter may be submerged in the noise of electromagnetic interference. The split electromagnetic flowmeter should be at least 5 meters away from transformers and motors. The installation position of the split electromagnetic flowmeter should ensure that the fluid in the pipeline is always full of the split electromagnetic flowmeter measuring tube, and there is a certain pressure, which requires the installation position to be at the lower end of the pipeline.