Introduction
According to Gin's law of thermal effect, there is a definite mathematical relationship between heating power P, temperature difference △ T (TRH-TRMG) and mass flow rate Q. P/△ T=K1+K2 f (Q) K3 K1, K2, K3 are constants related to the physical properties of the gas. The unique temperature difference measurement method of the thermal gas mass flowmeter overcomes the disadvantage that the thermal gas mass flowmeter based on the principle of constant temperature difference can not be measured due to the large zero drift caused by water, oil, and impurities in the gas when measuring the gas flow. It can also be used to measure the mass flow of wet gas, such as underground gas drainage, air supply, and real-time detection of air volume (speed) in the exhaust system.Features
Convenient installation, simple maintenance, two-way detection, anti-vibration
Correction of output analog quantity Multipoint nonlinear curve correction
Wide range ratio 100:1
Simultaneous detection of flow and temperature, switching displayLarge diameter and small flow measurements can be used for leakage detection
The sensor is packaged with proprietary technology "double-balanced structure"
Proprietary high humidity and high-temperature algorithm, medium temperature up to 500 ℃
Direct mass flow detection without temperature and pressure compensation
Working principle
The thermal flowmeter is a flow instrument designed based on the principle of thermal diffusion That is when the fluid flows through the heating object, the amount of heat loss of the heating object is proportional to the flow rate of the fluid The sensors of this series of flowmeters have two standard levels RTDs, one is used as a heat source and the other is used to measure the fluid temperature. When the fluid flows, the temperature difference between the two is linear with the flow, and then the relationship is converted into the linear output of the measured flow signal through the microelectronic control technology.
Classification
The thermal gas mass flowmeter can be divided into the plug-in type and pipe section type according to the installation mode.Plugin
The plug-in sensor can be installed and maintained online. The installation process is to first weld the base with an external thread on the outer wall of the pipe, install a 1-inch stainless steel ball valve on the base, then use a special tool to drill a hole with a diameter of 22mm in the pipe, remove the special tool after drilling, and finally install the sensor on the valve and insert the sensor into the center of the pipe (the insertion position of the sensor has been determined when leaving the factory). Applicable pipe diameter of plug-in sensor: DN80 ~ 6000mm.
Pipe segment type
When the pipe segment thermal gas mass flowmeter leaves the factory, it has been equipped with a process pipe with the same inner diameter as the on-site pipe. The flange connection or threaded connection is adopted for connection with the on-site pipeline. The flange standard complies with the national standard GB/T9119-2000. Applicable pipe diameter of pipe segment sensor: DN15~2000mm.
The sensor is made of stainless steel, and the pipe is made of carbon steel or stainless steel.
Application fields
- Measurement of oxygen, nitrogen, hydrogen, chlorine, and multi-component gas.
- Measurement of blast furnace gas and coke oven gas.
- Flue gas measurement.
- Aeration and chlorine measurement in biogas and water treatment.
- Compressed air measurement.
- Flow measurement of natural gas, liquefied gas, flare gas, etc
- Measurement of primary and secondary airflow of the blast furnace in the power plant
- Flow measurement of underground ventilation or exhaust system
- Air flow measurement in the gas process
- Measurement of flue gas flow (velocity) from the chimney (CEMS)
- Calciner flue gas flow measurement
- Gas flow measurement during the production of cement, cigarette, and glass plants
- Gas flow measurement in solvent recovery system
- Gas flow measurement in semiconductor chip fabrication
- Measurement of carbon dioxide gas flow in beer production
- Measurement of gas flow (velocity) in heating ventilation and air conditioning systems
- Measurement of combustion gas flow in a coal-fired boiler
- Real-time detection of flow (velocity) in underground ventilation or exhaust system

Technical Parameters
Applicable medium: all gases compatible with stainless steel- Measuring range: 0.05 - 120m/s
- Operating temperature: - 40 ℃ - 510 ℃
- Ambient temperature: - 40 ℃ - 85 ℃ Humidity less than 90% RH
For pipes with a diameter greater than or equal to 3 inches, the power requirements can be ignored:
- 18 - 30VDC Max. 600mA
- 180 - 230VAC 2.5W max
- 100VAC maximum 3.15W
- Output signal: 4-20mA linear proportional to mass flow and 4-20mA linear proportional to temperature
- Accuracy: 1% of reading ± 0.5% of the full scale
- Repeatability: ± 0.2% F. S
- Withstand voltage: 4.2MPa
- Response time: ≤ 850ms
- Housing material: die-casting aluminum, A2/A4 optional
- Probe material: 316L, tantalum, titanium, etc
- Ball valve: 316L
- Compression joint: 316L/304
- Flange: 316L/304
Display: widescreen LCD display, parameters, and variables can be set by pressing keys on the panel (with password protection)
Protection grade: IP65 (different grades from different manufacturers)
Applications
1. Utilities --- monitoring of power, gas, and water treatmentPipeline gas; Common system; Biogas; Gas; natural gas; liquid gas; Boiler preheating air
2. Oil and gas industry
3. Power industry
4. Chemical industry
5. Metallurgical industry
6. Pulp and paper industry
7. Food and medicine industry
8. Environmental protection
9. Other industries