the gas blending cabinet (also known as gas mixer, gas blending cabinet) is a specialized used to precisely mix two or more gases and output a mixed gas according to a preset ratio. It is widely used in welding, electronic manufacturing, medical, chemical, laboratory and fields. Its core function is to ensure the stability of the gas component ratio and meet the strict requirements of different scenarios for gas composition through automated control.

1. Basic Com Structure
the structure of the gas blending cabinet usually includes the following key parts, and each component works together to achieve the gas blending function:
Gas Source Interface and ValvesConnect different types of gas sources (such as bottled gas, pipeline gas), equipped with high-pressure valves, check valves (to prevent gas backflow), and filters ( remove impurities, moisture, and protect equipment).
Pressure Regulating System
Includes a pressure regulator (to reduce high-pressure gas source to the working pressure of the) and a pressure sensor (to monitor gas pressure in real-time and ensure stable gas supply).
Flow Control Module
the core component, usually using a mass flow controllerMFC) or rotameter, accurately controls the flow of each gas according to the preset ratio. the mass flow controller has higher accuracy (within ±1% or less) is suitable for scenarios with strict blending requirements.
Mixing Chamber
Multiple gases are fully mixed here. the internal design usually adopts a disturbance structure or diffusion device to ensure uniform and avoid stratification.
Control System
Composed of PLC (Programmable Logic Controller), touch screen or keypad panel, it can set the mixing ratio, flow, and display the flow, mixing ratio, and equipment status (such as alarm information) of each gas in real-time. Some high-end models support remote control (such RS485, Ethernet interface).
Safety Devices
Including overpressure protection valve, leakage detector, emergency shut-off valve, etc. When the gas pressure abnormal or leakage occurs, it automatically cuts off the gas source and alarms to ensure operation safety.
2. Working Principle
the working process of the gas mixing cabinet is based on the logic of "accurate flow control - uniform mixing stable output", and the specific steps are as follows:
Gas Source Access and Pre-processing
Different types of gases (such as argon   carbon dioxide,   nitrogen) enter the equipment through gas source interfaces separately, and after passing through filters to remove impurities, the pressure is regulated to a stable working pressure (usually 0.-0.6MPa) by pressure regulators.
Flow Setting and Regulation
the operator inputs the target mixing ratio (such as 80% argon   20 carbon dioxide) through the control system, and the system calculates the required flow rate for each gas according to the ratio and sends instructions to the flow controller. the mass flow controller the actual flow rate in real time through sensors, dynamically adjusts the valve opening after comparing with the target value, and ensures that the flow rate matches accurately.
Gas Mix
the gases controlled by the ratio enter the mixing chamber, fully stirred and diffused through the internal structure, and form a uniform mixed gas. the mixed gas is regulated by a stabilizing device (such as a pressure regulator) to meet the pressure requirements of downstream equipment (such as welding machines, reactors).
Monitoring and Feedback
the control collects real-time data such as gas flow, pressure, mixing ratio, etc., and if there is any deviation (such as flow fluctuation, pressure abnormality), alarm is immediately issued (audio-visual alarm or screen prompt), and the deviation is corrected by adjusting the flow controller, and the gas source is automatically cut off when necessary