How to improve the measurement accuracy of thermal gas mass flowmeter

In the industrial field, companies need to use natural gas, hydrogen and other gas in many process production, sometimes also need oxygen, nitrogen, argon and other made of gas, this part of the gas cost needs to be controlled and monitored, and the selection of monitoring instruments need to consider various issues:

Common faults encountered with thermal mass flowmeters can disrupt their accurate measurement capabilities. Here are some typical issues along with potential solutions:

The thermal gas mass flowmeter uses the principle of thermal diffusion, and its working principle determines the change of the measured medium gas with the temperature and pressure, which affects the data change of the measured results.

Thermal gas mass flowmeters are a type of mass flowmeter specifically designed for measuring the flow rate of gases, while mass flowmeters, in a broader sense, can measure the flow rate of both gases and liquids. Here are some key differences between thermal gas mass flowmeters and other types of mass flowmeters:

When selecting a thermal mass flowmeter, several important factors should be taken into consideration to ensure it meets the requirements of the application and provides accurate and reliable measurements. Here are key points to pay attention to:

The application of thermal gas mass flow meter in various industries

At the heart of a thermal mass flow meter is a sensor that heats up a portion of the gas stream while monitoring the temperature difference between the heated and unheated sections. As the gas flows over the heated sensor, it carries away heat, and the temperature difference provides a direct measurement of the mass flow rate. The beauty of this method lies in its ability to provide accurate readings across a wide range of flow rates, from low to high velocities, ensuring versatility and reliability in various industrial settings.

Structural form: plug-in pipelined
Measuring medium: All gases (except acetylene)
Pipe diameter range: Caliber DN32 or higher DN10～DN2000mm
Velocity range: 0.1～120Nm/s
Precision: ±1～2.5%
Operating temperature: Sensor：-40℃～+220℃
convertor：-20℃～+45℃
Working pressure: Medium pressure≤2.5Mpa
Medium pressure≤4.0Mpa
Power supply: DC24V or AC220V≤18W

The thermal mass flowmeter is an device for measuring gas flow by using the principle of thermal diffusion. The sensor consists of two reference thermal resistors (RTDS). One is the speed sensor RH, and the other is the temperature sensor RMG, which measures the temperature change of the gas. When the two RTDS are placed in the measured gas, one sensor RH is heated and the other sensor RMG is used to sense the measured gas temperature. As the gas flow rate increases, the airflow carries away more heat, and the temperature of the sensor RH drops.

Measuring medium: Various gases (except acetylene gas)
Pipe diameter range: DN10-2000mm
Accuracy Degree: ±1～2.5%
Pipe material: Carbon steel, stainless steel, plastic, etc

In order to solve the problem of leakage caused by poor measurement accuracy or inability to measure below the lower limit of the instrument, a new type of thermal gas mass flowmeter is developed based on the theory of forced convection heat transfer and the principle of hot wire anemometer. The sensitivity of the instrument is greatly improved and the dead zone of the instrument is reduced by using microfilament structure in the sensitive element and the velocity measuring heating element.

Direct measurement of gas mass, without temperature, pressure compensation of gas flow measurement instrument, it represents the development trend of gas flow measurement. The thermal mass flowmeter sensor part is composed of two reference platinum resistance temperature sensors, using a bridge loop, one sensor measures the fluid temperature, and the other sensor is a heating element, maintaining a constant temperature difference higher than the fluid temperature, that is, when the gas flows through the heating element, the heat is taken away, and the heat is proportional to the flow rate of the gas and the density of the gas. To maintain a fixed temperature difference between the two temperature sensors requires the circuit to provide more power to the heating element, and the amount of output power in the circuit is related to the mass of the fluid, thus measuring the flow rate.

Measuring medium: Various gases (except acetylene gas)
Pipe diameter range: DN10-2000mm
Accuracy Degree: ±1～2.5%
Pipe material: Carbon steel, stainless steel, plastic, etc

When applying a thermal mass flowmeter, several key points need to be considered to ensure accurate and reliable measurement. Here are some important factors to pay attention to:

Thermal mass flowmeters are known for their ability to provide accurate and reliable measurements of fluid flow rates, regardless of changes in pressure and temperature. This resilience to pressure and temperature variations is due to the operating principle of thermal mass flowmeters and their design features. Here’s why thermal mass flowmeters are not significantly affected by changes in pressure and temperature:

The thermal gas mass flowmeter is designed based on the principle of thermal diffusion. The meter uses constant temperature difference method to measure the gas accurately. The thermal gas mass flowmeter has the advantages of small volume, high digitization, easy installation and accurate measurement.

The selection of flue gas flowmeter is a complicated but critical process, which is directly related to the accuracy of measurement results and the reliability of equipment. Here are some of the main factors to consider in the selection process:

Thermal gas mass flowmeter has certain operating procedures and precautions in use, and must pay attention to these points when in use:

The thermal gas mass flowmeter is an instrument that uses the principle of heat conduction to measure fluid flow. The instrument uses the constant temperature difference method to measure the gas flow accurately. It has the advantages of small size, high digitization, easy installation and accurate measurement.

The data show that in the flow measurement failure probability, the improper selection of flowmeter accounts for about 70%, and the quality of flowmeter products or other reasons account for 30%, which shows how important the selection of flow measurement is.

Thermal gas mass flowmeter adopts the principle of thermal diffusion, and thermal diffusion technology is a technology with excellent performance and high reliability under harsh conditions.

In-line thermal mass flowmeter is equipped with the same process pipe with the same inner diameter as the field pipe. The connection with the field pipe is flange connection or thread connection. Pipe segment sensor applicable pipe diameter: DN15 ~ 2000mm.

Measuring medium: Various gases (except acetylene gas)
Pipe diameter range: DN10-2000mm
Accuracy Degree: ±1～2.5%
Pipe material: Carbon steel, stainless steel, plastic, etc

The thermal gas mass flowmeter is an instrument for measuring fluid flow by using the principle of heat conduction. The instrument uses constant temperature difference method to accurately measure the gas mass flow.

Choosing the correct installation direction for a thermal gas mass flowmeter is essential for optimal performance and accurate measurement. The installation direction should be determined based on factors such as the flow profile, flow conditions, and manufacturer recommendations. Here are some guidelines to help you choose the appropriate installation direction for a thermal gas mass flowmeter:

1. Principle of thermal gas mass flowmeter

Thermal gas mass flowmeter The thermal distributed flowmeter uses the flow fluid to transfer heat to change the heat conduction distribution effect of measuring the temperature distribution of the tube wall. 2) King’s Law using the heat dissipation (cooling) effect. And because the structure of the detection element extends into the measuring tube, also known as immersion or intrusion type. Some instruments that are inserted from outside the tube into the process tube when in use are called plug-in.

The thermal gas mass flowmeter is an instrument that uses the principle of heat conduction to measure flow. The instrument uses the constant temperature difference method to accurately measure the gas mass flow rate. It has the advantages of small size, high digitization, easy installation, accurate measurement and so on.

The thermal gas flowmeter has many remarkable characteristics, which make it widely used in the field of gas flow measurement. The following are the main features of thermal gas flowmeters:

Thermal gas mass flowmeter is the use of fluid flowing through the pipe heated by an external heat source when the temperature field changes, is a high-sensitivity, high-precision gas measurement instrument, in the gas flow measurement conditions, good stability, used for gas process control and gas flow measurement one of the most used instruments.

Thermal mass flowmeters are widely used in various industries due to their ability to measure the flow rate of gases accurately. Here are some applications of thermal mass flowmeters across different industries:

The correct use of gas flowmeters is the key to ensure accurate and reliable measurement results. The following is the correct use of gas flowmeters:

Thermal Gas Mass Flow Meter is also divided into flange link Thermal Gas Mass Flow Meter and plug-in link Thermal Gas Mass Flow Meter, The following describes the application scope of the Thermal Gas Mass Flow Meter.

Thermal gas mass flowmeter is the use of fluid flowing through the pipe heated by an external heat source when the temperature field changes, is a high-sensitivity, high-precision gas measurement instrument, in the gas flow measurement conditions, good stability, used for gas process control and gas flow measurement one of the most used instruments.

When selecting a thermal mass flowmeter, several important factors should be taken into consideration to ensure it meets the requirements of the application and provides accurate and reliable measurements. Here are key points to pay attention to: