Installation of electromagnetic flowmeter with air bubbles solution

Electromagnetic flowmeter is a high-precision flow measurement instrument. In order to ensure the accuracy of measurement, special attention needs to be paid during installation. Next, let's talk about several problems that are easily encountered when installing electromagnetic flowmeter.

1. The installation location is incorrect.

It is common to install the sensor at a higher point in the piping system where gas accumulation is easy, or install it on a top-down vertical pipe, which may cause emptying, or there may be no back pressure behind the sensor, and the fluid will flow directly It is discharged into the atmosphere and the measuring tube is not full.

The measured liquid contains evenly distributed tiny bubbles which usually do not affect the normal operation of the electromagnetic flowmeter. However, as the bubbles increase, the meter output signal will fluctuate. If the bubbles are large enough to cover the entire electrode On the surface, as the bubbles flow through the electrode, the electrode circuit will be instantly disconnected, causing greater fluctuations in the output signal.

2. The electromagnetic flowmeter electrode material and the measured medium are improperly selected.

How to select improperly? Normal measurement will be affected due to chemical effects or polarization phenomena. Electrode materials should be selected correctly according to the instrument selection or relevant manuals.

The electromagnetic flowmeter is a flow meter with accurate measurement. Its installation needs to follow certain specifications. Next, let’s talk about the environmental requirements when the electromagnetic flowmeter is installed outdoors.

1. The electromagnetic flowmeter should avoid being installed in places where the temperature changes greatly or is subject to high temperature radiation from the equipment. If it must be installed, heat insulation and ventilation measures must be taken.

2. Try to install it indoors. If it must be installed outdoors, it should be protected from rain, flooding and sun exposure. In addition, moisture-proof and sun-proof measures are required.

3. Installation in an environment containing corrosive gases should be avoided. When installation is necessary, ventilation measures must be taken.

4. In order to facilitate the installation, maintenance and maintenance of the electromagnetic flowmeter, there must be ample installation space around the electromagnetic flowmeter.

5. The installation site of the flowmeter should avoid magnetic fields and strong vibration sources. If the pipeline vibrates greatly, there should be supports to fix the pipeline on both sides of the electromagnetic flowmeter.

Electromagnetic flowmeter is a widely used flow meter, especially often used in industrial measurement. Occasionally, customers will encounter the presence of bubbles when measuring liquid media. To this we simply Let’s explain the specific solution.

What are the effects of bubbles in the measured medium.

1. It is easy to cause measurement errors in the electromagnetic flowmeter.

2. The electrode is in a horizontal position, and the mixed bubbles float on the upper part of the sensor. According to the weight function analysis, there is no induced potential on the upper part of the sensor, so a negative error will occur.

3. If the bubbles are concentrated in the part where the W×B product (the product of the magnetic induction electromagnetic flowmeter intensity and the weight function) is low, when the bubbles are dispersed, a positive error will appear in the measurement output. On the contrary, the bubbles are concentrated in W× For parts with a high B product, negative errors will appear in the measurement output.

The above is the impact of bubbles contained in the electromagnetic flowmeter measurement medium. It is indeed very large, so it is recommended that everyoneAfter it is determined that a large number of bubbles will affect the measurement results, a corresponding solution must be found. If it is determined that a large number of bubbles are incorporated into the liquid due to the installation location, such as the electromagnetic flowmeter being installed at a high point in the piping system to store gas or inhaling air from the outside. If the flowmeter shakes, changing the installation position is an effective solution. However, in many applications, the diameter is large or the installation position is difficult to change. It is recommended to install a gas collection bag and an exhaust valve upstream of the electromagnetic flowmeter to eliminate excess gas and reduce damage to the flowmeter. Factors affecting the measurement results to ensure accurate measurement.