Thermal gas mass flowmeter is an instrument that uses the principle of thermal diffusion to measure gas flow rate. The sensor consists of two reference level thermal resistors (RTDs). One is the speed sensor RH, and the other is the temperature sensor RMG that measures changes in gas temperature. When these two RTDs are placed in the measured gas, the sensor RH is heated, and the other sensor RMG is used to sense the temperature of the measured gas. As the gas flow rate increases, the airflow carries away more heat, and the temperature of the sensor RH decreases.
Manufacturer of thermal gas mass flowmeter
The thermal gas mass flowmeter adopts LCD liquid crystal display, which can measure and read in one step. The LCD screen displays instantaneous flow rate, cumulative flow rate, medium flow rate, etc. on-site. It is designed with anti-interference circuit, lightning protection, circuit surge protection, and efficient anti-interference. The measurement values are more stable and suitable for various harsh environments. If on-site conditions permit, non-stop installation and maintenance can be achieved. Its instantaneous units include Nm3/h, Nm3/min, NL/h, NL/mint/h, t/min, kg/h, and kg/min. Accumulated units include NM3 NL、t、kg。
Working principle of hot gas mass flow rate
Thermal flowmeter is a flow meter designed based on the principle of thermal diffusion When a fluid flows through a heating object, the amount of heat lost by the heating object is proportional to the flow rate of the fluid The sensors of this series of flow meters have two standard grade RTDs, one used as a heat source and the other used to measure fluid temperature. When the fluid flows, the temperature difference between the two is linearly related to the flow rate, and this relationship is then converted into a linear output of the measured flow signal through microelectronic control technology.
Classification of mass flow rate of hot gases
Thermal gas mass flow meters are divided into plug-in and pipe section types according to installation methods.
Insertion type
Plug in sensors can be installed and maintained online. The installation process is to first weld a base with external threads on the outer wall of the pipeline, install a 1-inch stainless steel ball valve on the base, and then use a special tool to drill a hole with a diameter of 22mm in the pipeline. After drilling, remove the special tool, and finally install the sensor on the valve and insert it into the center of the pipeline (the insertion position of the sensor is determined at the factory). Plug in sensors are suitable for pipeline diameters: DN80～6000mm。
Pipe section type
The segmented thermal gas mass flowmeter is equipped with a process pipeline with the same inner diameter as the on-site pipeline when it leaves the factory. The connection method with the on-site pipeline is flange connection or threaded connection. The flange standard complies with the national standard GB/T9119-2000. Pipe segment sensor is suitable for pipeline diameter: DN15～2000mm。
Application scenarios
- Public works – monitoring of electricity, gas, and water treatment
Gas in pipelines; Universal system; Biogas; Gas; natural gas; liquid gas; Preheating air for boiler - Oil and gas industry
Energy exchange; Gas recovery from filling wells; Gas metering; Gas quality analysis; Leakage test; Natural gas measurement; Monitoring of Torch Gas - Power industry
Gas measurement during gas distribution in fuel systems; Measurement of various gases in boilers and auxiliary systems; Gas measurement in gas furnaces; Hydrogen measurement; Measurement of primary and secondary air in power plant blast furnaces - Chemical industry
Smoke circulation monitoring; Gas flow measurement in sampling system; Gas flow measurement of induced draft fan; Measurement of ammonia gas in fertilizer plants; Measurement of various gas flow rates in battery factories - Metallurgical industry
Gas filling measurement in steel plants; Measurement of blast furnace gas in ironworks; Measurement of coke oven gas in coking plants; Measurement and control of heating furnace gas (blast furnace gas, coking gas, natural gas, etc.) in steel rolling mills; Control of gases such as hydrogen, oxygen, and nitrogen in heat treatment quenching furnaces, etc - Pulp and paper industry
Measurement of gases in wastewater treatment systems; Smoke flow monitoring; Boiler recovers secondary/tertiary air; Measurement of gas and air supply for boilers - Food and pharmaceutical industry
The addition of fresh air during processing operations; CO2 treatment in breweries; The flow rate of hot air in the bottle sterilizer; Measurement of gas flow rate during thermal oxidation process; Ventilation system; Boiler inlet, exhaust gas, process control - Environmental Protection
Gas measurement during biogas utilization process; Measurement of chlorine gas during chlorine treatment process; Gas measurement in aeration tanks during sewage treatment process; Monitoring the emissions of SO2 and NOX in the exhaust of chimney and flue gas - Other industries
Factory compressed air measurement; Coal powder combustion process with powder/gas ratio control fuel; Control of Hot Gas Flow from Vertical Grinding Mill in Cement Industry