What are gas flow sensors used for?

With the continuous development of industrial automation level. Gas flow sensors play an important role in various fields. For human production and life has created an immeasurable contribution.

Concrete main role is divided into the following points: 

First, real-time monitoring of gas flow, access to flow parameters, to provide a basis for subsequent control. Second, according to the measurement feedback real-time adjustment of gas flow, to achieve precise control. Third, with the industrial process equipment to form a closed-loop control, to ensure that the gas supply is stable in line with process requirements.

Classification And Trends

1、Thermal gas flow sensor. Based on the principle of heat conduction, Inline or Bypass mode. They are the most commonly used type because of their high accuracy, fast response and resistance to high temperatures and pressures.

2、Differential pressure gas flow sensor. Calculate the flow rate according to the pressure change when the gas passes through the pipeline. Simple structure, no need for electricity, but lower accuracy.

3、Turbine gas flow sensor. Utilizing the gas flow through the impeller impeller rotation speed calculation flow. Fast response, but affected by the installation position.

4, Ultrasonic gas flow meter. Calculate the gas flow rate through the acoustic signal change between the sensor. Completely non-contact, high accuracy, but more expensive.

5, MEMS gas flow sensor. Based on MEMS microelectromechanical technology, small size, low power consumption, good accuracy, is an emerging technology.

Today, heat-based gas flow sensors are still the mainstream products because of their high accuracy, fast response and other advantages. But pressure and MEMS-based flow sensors are also developing, with small size, low power consumption and other characteristics. The future miniaturization and intelligence will be the development trend.

Application Cases

• Natural Gas Pipeline Network

Natural gas pipeline network is an important infrastructure for city gas supply. In order to ensure that each customer can obtain a stable amount of natural gas, it is necessary to monitor the gas flow in the network in real time to achieve a balance between supply and demand.

By installing gas flow sensors in the network, the gas flow rate and flow rate of each pipe section can be continuously detected. According to the actual gas consumption of the user, control and adjust the gas flow in the pipeline to realize the precise adjustment of gas supply. When the gas flow of a pipe section is too large, the pressure and flow of each pipe section can be balanced by adjusting the opening of the valve.

Gas flow sensor feedback real-time data, can also be used for pipe network pressure monitoring. If abnormal pressure is detected at a node of the pipe network, the problem can be quickly localized and measures can be taken.

• Industrial Combustion Furnaces

In all types of industrial combustion furnaces, accurate control of the fuel gas flow is critical to ensure adequate combustion and to improve the thermal efficiency of the furnace.

Traditional industrial combustion furnaces rely on manual experience to adjust the valve opening to control the amount of gas. This way can not detect the gas flow in real time, and it is easy to lead to too much or not enough gas supply.

The use of gas flow sensor can be real-time detection of gas flow rate and flow, and combined with the combustion furnace flame conditions, to achieve closed-loop control system. When the sensor detects that the gas flow deviates from the optimal value, it can immediately feed back the adjustment signal, precisely control the valve opening, and restore the gas flow to the optimal state.

This ensures that the fuel gas flow in the industrial combustion furnace is always at the level of full and complete combustion, which not only improves energy efficiency, but also reduces gas consumption and pollution emissions. Closed-loop gas flow control makes the whole combustion process more intelligent and economical.

• Automotive Spraying Lines

In an automotive coating line, the gas used for coating must have a constant flow rate. This is very important to achieve high quality coating results.

Conventional gas flow control methods are unable to detect small changes in flow rate in real time. By using a gas flow sensor, the flow rate of the spray gas can be continuously monitored and if fluctuations in the flow rate are detected that exceed the permissible range, the sensor can provide rapid feedback to the control signal. The sensor can quickly feedback control signals, drive the opening of the regulating valve, the gas flow rate back to the set value.

This can effectively reduce the gas flow fluctuations in the spraying process to ensure stable spraying results. Avoid uneven spraying or insufficient spraying volume caused by product quality problems, improve the automation and quality stability of automotive spraying.

At the same time, the gas flow closed-loop control system can also continuously record the consumption of spraying gas. This facilitates production process monitoring and optimization of gas consumption statistics.

What are the important factors in gas flow sensor selection?

First, the measurement range and accuracy requirements. Products with appropriate measurement range and accuracy should be selected according to the actual process gas flow rate and control accuracy requirements.

Then, the operating environment, such as temperature, pressure, corrosiveness, etc., should be considered. Select the sensor structure and material suitable for these conditions to ensure that it can work stably for a long time.

In addition, response time is also important. Meet the monitoring response requirements of the process to flow changes. It is also necessary to consider the stability and reliability of the product, and choose a brand product with better quality.

Finally, the application scenario. Only when the various technical indicators of the gas flow sensor can fully adapt to the requirements of the application scenario. In order to give full play to the maximum effect of monitoring and control, to achieve accurate gas flow measurement.