Function and principle of laboratory airtight valves

Airtight valveIt is an electric one-way valve. When the closed valve is not energized, under the pressure of a strong spring, the valve will not open due to the reverse airflow. Effectively ensuring the airtightness of the corresponding space. It is usually connected to the valve body through an electric actuator and becomes an HVAC control valve after installation and debugging. The valve is powered by electricity and connected to an electric actuator to drive the valve, achieving the opening, closing, and regulating actions of the valve. In order to achieve the purpose of switching or regulating the pipeline medium. Equipped with reverse and locking functions, the heating and water supply systems can be turned on and off one by one, and cannot be opened in a non-destructive manner, thus achieving effective control.

　　The working principle of an airtight valve is similar to that of a dry pump, but due to the oil lubrication function of this type of pump, the lubricated spare parts and moving parts can obviously obtain higher pressure, which is one of the advantages of an airtight valve. However, the presence of lubricants makes it necessary to filter exhaust gases to recover lubricants and discharge as clean air as possible into the atmosphere. The size of the exhaust filter determines the pressure range within which these pumps can be continuously used.

      However, due to the influence of lubrication, the laboratory inevitably absorbs a small amount of water vapor. In order to prevent condensation of water vapor in the pump, the pump is designed with a gas ballast device, just like the pump must be equipped with an exhaust filter to prevent fuel injection and smoke, which protects the pump and makes the laboratory pumping process smoother. During the compression stage, some air will be added to the gas ballast to regulate the saturation pressure of the steam and prevent condensation. In addition, a backflow prevention valve should be installed at the inlet of the airtight valve to prevent oil from flowing back into the system during shutdown. What is the principle of a gas tight valve?

      At a given temperature, steam is compressed to saturation pressure, beyond which it condenses. At room temperature, the boiling point of water decreases. In the first stage, the pump will draw in a mixture of air and water vapor. In the second stage, the intake volume is isolated from the original container and exhaust pipe. At this stage, open the valve on the air valve and add a certain amount of air to change the saturation pressure of the mixture. In the later stage, it is discharged through the exhaust filter (i.e. exhaust filter element). However, due to changes in saturation pressure, condensate droplets will not form and will not interfere with their operation.

      The function of a gas tight valve is to prevent steam condensation. The principle is to change the saturation pressure of the mixture by adding a certain amount of air to avoid condensation, formation of water droplets, and contamination of the pump oil. If the pump oil emulsifies, the exhaust filter will be blocked, causing fuel injection and smoke, and polluting the atmospheric environment.