Instrument Mesurement Knowledge

What is the Effect of Gas in the Measured Medium?

Views: 6     Author: Site Editor     Publish Time: 2021-08-26      Origin: Site

What is the effect of gas in the measured medium?

1. The zero point of magnetic flowmeter is unstable.


2. The output signal of the magnetic sensor fluctuates or no signal is output:


If the bubbles in the medium tube become larger or unevenly distributed, the bubbles will cover the electrodes and disconnect the flow signal input circuit, which will lead to the disconnection of the output signal, which will lead to the fluctuation of the output signal and ultimately affect the accuracy of the flowmeter.


3. The measured value will be inconsistent with the actual value.

What is the influence of gas in the measured medium?

1.The air in the pipe is not exhausted fully.


2.Improper installation method causes more bubbles to enter the medium pipeline.


3.The Conversion of the dissolved gas: Owing to the temperature and pressure of the liquid changing in the pipeline, the dissolved gas is converted into free gas (bubbles).

Improper installation method:

A. when the electromagnetic flowmeter is installed vertically, the liquid flow direction is from top to bottom.

B. The electromagnetic flowmeter is not installed at the lowest point of the pipeline system.

How to eliminate bubbles in pipes?

1. If air bubbles are caused by improper installation position, please change the installation position of electromagnetic flowmeter.


2. If it is not easy to change the installation position: install an air bag or exhaust valve upstream of the magnetometer to remove the gas in the pipeline and avoid gas accumulation (If the accumulated gas covers the electrode, it will affect the measurement accuracy).