How Mass Flow Controllers Work
sales01@cxflowmeter.com
Mass flow controllers can be used to control a variety of clean and dry gases, including corrosive and special gases, but the use of corrosive and special gases requires the correct selection of models and sealing materials. When ordering, the user should contact the supplier to make special instructions when using the gas, so as to avoid serious losses due to wrong selection or sealing material. General mass flow control
The material of the brake contacting the working gas is 316L stainless steel, and the sealing material is divided into metal welding, PTFE and ordinary fluorine rubber glue. MFCs with metal welded seals for mass flow controllers can in principle be used for any gas, including various corrosive and special gases. For highly corrosive gases such as boron tribromide, boron trichloride, hydrogen fluoride and gold used in MOCVD
The oxidizing gas is recommended to use a metal-welded sealed
MFC.
The mass flow controller is composed of a flow sensor, a shunt channel, a flow regulating valve, an amplifying controller, etc.
The sensor of the mass flow controller uses the principle of capillary heat transfer thermocalorimetry to measure the mass flow of gas (without temperature and pressure compensation). The flow signal measured by the sensor heating bridge is sent to the amplifier for amplification, and the amplified flow detection voltage and set value
The voltages are compared and the difference signal is amplified to control the regulating valve. The closed loop controls the flow through the channel to be equal to the set consistent flow. The diverter determines the flow of the main channel. Flow Indicators with Mass Flow Controllers with Voltage Regulators
Power supply, digital voltmeter, setting potentiometer, peripheral equipment, built-in conversion and three-position valve control switch, etc.
Mass flow controllers can easily and accurately monitor the flow in pipelines without temperature and pressure compensation. Various gas and thermal gas mass flow meters are a new type of flow measurement and monitoring instruments.
The mass flow controller adopts the principle of thermal diffusion, and the thermal diffusion technology has excellent performance and high reliability under harsh conditions. Its typical sensing element consists of two thermal resistances (platinum RTDs), one is a speed sensor and the other is a self-compensating gas
Temperature sensor for body temperature changes. When both RTDs are placed in the medium, the speed sensor is heated to ambient temperature and the other temperature sensor is used to sense the medium temperature. The gas flow through the velocity sensor is calculated from the heat transfer from the sensing element. As the gas flow rate increases, the heat carried away by the medium increases. sensing
The temperature of the filter decreases. To keep the temperature constant, it is necessary to increase the operating current of the mass flow controller. The current applied is proportional to the flow rate of the medium.
Mass flow controllers are instruments that measure fluid flow using the principle of heat conduction. The mass flow controller uses the constant temperature difference method to accurately measure the gas mass flow. The mass flow controller is small in size, high in digitization, and easy to install. The quantity is accurate. Mass flow controllers can be used in actual working conditions of hydrocarbon gas, combustible gas and smoke in industrial enterprises such as glass, solar energy, atmospheric monitoring, industrial production, petroleum and petrochemical, coal gas pipeline distribution control, carbon metallurgy, gas production and distribution, environmental protection and other industrial enterprises Measurement and monitoring of mass flow or volume flow of lower channel gas.
If you want to know more parameters and quotation of mass flow controller, please contact winny: sales01@cxflowmeter.com