A one-way constant pressure valve is installed at the output end of the mass flow controller to maintain the fixed pressure difference between the inlet and outlet of the "digital mass flow controller" and limit the gas distribution pressure, so as to ensure the stability and safety of the control flow. The wetted surface is composed of stainless steel and polytetrafluoroethylene PTFE, which is clean and guaranteed. The pipeline is silanized to ensure the accuracy and purity of gas distribution. ·The system is controlled by HM touch screen. Nitrogen can be used alone to pressurize or clean Suma tank. All cleaning data are displayed on the man-machine interface, which is convenient for users. ·The system uses "absolute pressure sensor" and "small hole current limiting device" to automatically monitor the internal pressure of the sampling tank, which makes the gas distribution more accurate and reliable and the effect of constant speed gas distribution under constant pressure. The HMI of HM touch screen is equipped with RS232, RS485, USB, Ethernet and other communication ports, which is convenient for users to remotely operate the diluter, realize online software upgrade, remote access to gas distribution data and other functions
The interface of HM I touch screen system is humanized. There are two different display styles, and more functions can be realized by upgrading software in the future.