Basic Components
The working principle of explosion-proof electromagnetic flowmeter is mainly based on Faraday’s law of electromagnetic induction.
The explosion-proof electromagnetic flowmeter consists of two parts: a sensor and a converter. The sensor is installed on the measuring pipe to detect the induced electromotive force generated when the fluid flows; the converter is responsible for converting the signal detected by the sensor into readable flow data, which can be further processed or displayed.
Working Principle
1. Magnetic field generation: The sensor of the explosion-proof electromagnetic flowmeter contains an excitation coil. When current is passed through it, the excitation coil will generate a constant or alternating magnetic field. This magnetic field runs through the entire measuring pipeline, providing conditions for the generation of induced electromotive force when the fluid flows.
2. Fluid cutting magnetic flux lines: When conductive media (such as water, sewage, mud, etc.) flow through the sensor, they cut the magnetic flux lines generated by the excitation coil.
In this process, the free electrons in the conductive medium will be affected by the Lorentz force and move in a directional manner, thereby generating an induced electromotive force.
3. Induced electromotive force detection: The electrodes inside the sensor are responsible for detecting this induced electromotive force.
The magnitude of the induced electromotive force is proportional to the flow rate of the conductive medium, the magnetic induction intensity of the magnetic field, and the inner diameter of the measuring pipe (i.e. the flow meter measuring pipe diameter).
Therefore, by measuring the magnitude of the induced electromotive force, the flow rate of the conductive medium can be calculated.
4. Flow calculation: The converter receives the induced electromotive force signal detected by the sensor, and after a series of signal processing and calculation, it finally converts the flow rate into flow data. This flow data can be instantaneous flow or cumulative flow, depending on the programming and settings of the converter.
Accuracy and Characteristics
1. The explosion-proof electromagnetic flowmeter has high accuracy, and its measurement accuracy will not be affected by changes in fluid density, viscosity, temperature, pressure and conductivity.
2. The measuring tube inside the sensor has no parts that hinder the flow of liquid, so there will be no pressure loss, and the installation requirements for straight pipe sections are relatively low.
3. In the sensor part, only the lining and electrodes are in contact with the measured liquid. Therefore, as long as the electrode and lining materials are selected reasonably, corrosion resistance and wear resistance can be achieved.
Application
Explosion-proof electromagnetic flowmeters are widely used to measure the volume flow of conductive liquids and liquid-solid two-phase fluids, and are particularly suitable for industries such as petroleum, chemical, metallurgy, textile, food, pharmaceutical, papermaking, as well as environmental protection, municipal management, water conservancy construction, etc. Due to its explosion-proof characteristics, it is particularly suitable for inflammable and explosive industrial environments.
Conclusion
The explosion-proof electromagnetic flowmeter achieves high-precision measurement of the flow of conductive media by utilizing Faraday’s law of electromagnetic induction.
Its unique composition structure and working principle enable it to provide accurate and reliable flow data in various industrial environments.