The structural characteristics of the new single-valve multi-way liquid seal valve are introduced. The combination of the valve plate and the independent liquid seal chamber can inject liquid into the independent liquid seal chamber after the valve plate is closed, thus forming a reliable disconnecting device, thereby avoiding blind Block pumping operation. 1. Overview At present, the air flow which is reliably cut off the gas pipeline is usually used after the butterfly valve or the gate valve is sealed to form the partition device by using one of the blind plate, the plug plate, the eye valve and the sector valve or the double plate cut-off valve as the partition device. This article describes a new single valve multi-way liquid seal valve to replace the eye valve, fan valve and double plate shut-off valve. 2, the analysis of modular partition devices are used in the body flange or pipe flange rigid blocker, insert or withdraw rigid blocker must be manually or mechanically release - clamping seal, to achieve the media cut off . After the pipeline is put into use, there may be sediment in the valve seat of the sealing butterfly valve, gate valve or plug-in board, which will affect the close fitting between the sealing pair of the valve plate and the valve seat when the valve is closed. Therefore, blind operation in blocking plugging or opening and closing of the eye valve or fan valve, there will be hazardous gas escape, resulting in job intensity, high risk. In addition, the combined partition device sealing parts and more complex mechanical structure. Double plate cut-off valve cut off device in the pipeline after the valve seat may have sediments affect the valve closure of the sealing plate and the valve seat close fit, this time, through the continuous to both sides of the valve plate and the valve The body cavity is filled with liquid to ensure that the hydrostatic pressure of the seal is greater than the pressure of the gas medium so as to ensure that the gas medium does not leak to the partitioned side. Double plate cutting valve manufacturing difficult, especially the two valve plate concentric assembly precision and sealing surface grinding. The two valves of the valve are synchronously reversed or raised and lowered by the link transmission mechanism. The failure of a single block affects the valve plate opening and closing, which makes the troubleshooting difficult. In order to overcome the shortcomings of the combined type and the double-plate cut-off partition device, a new type of single-valve multi-way liquid seal valve (referred to as the liquid seal valve, the same below) is designed. The valve has applied for a national invention patent (application number 2009103037153). 3, working principle Liquid seal valve is mainly composed of valve body, valve plate, valve seat, valve plate transmission mechanism, upper diaphragm and upper diaphragm transmission mechanism. The independent liquid sealing chamber is arranged in the valve body, and is formed by the upper bottom plate and the bottom plate of the valve body being nested with each other. The upper partition is inverted cup-shaped, the whole can be upward and downward directional movement, the upper partition is provided with a ring-shaped multilayer partition. The lower plate of the valve body is cup-shaped, fixed, the lower plate is also provided with a ring-shaped multilayer separator. When the valve is closed, firstly the valve plate is closed, then the upper partition plate is driven by the transmission mechanism so that the annular multi-layer partition plate of the upper partition plate is inserted into the annular multi-layer partition plate on the lower plate plate from up to down, The annular multi-layer baffle and the annular multi-layer baffle on the bottom plate are nested with each other to form a multi-pass liquid-sealed cavity. Open the valve body drain / mouth height of the liquid seal height after the release valve to the atmosphere to disperse, you can observe whether there is a continuous escape of gaseous medium to determine the valve seat and valve seal is close fit. Even if the sealing seat between the valve seat and the valve plate fails to fit closely, the liquid injection valve is opened to fill the liquid sealing chamber, and the liquid is gradually overflowed along the inner annular partition until the liquid is observed from the discharge port / liquid seal height After the mouth overflows, you can stop the infusion. The height of the liquid seal in the liquid seal chamber ensures that the gas medium does not leak to the partitioned side. Open the valve, the first open the body drain port at the drain valve, the fluid within the lumen of each row of the liquid drain and then turn off the drain valve, and then close the drain / liquid seal height observation port After the valve. And then driven by the transmission mechanism to move the upper partition to the upper part of the valve body so as to separate the annular multi-layer partition plate of the upper partition plate from the nested structure formed by the annular multi-layer partition plate on the lower floor plate so that the valve body can become a smooth gas Flow channel, and finally open the valve plate. 4, the structural design based on different design and installation requirements, liquid-sealed valves are vertical, horizontal and horizontal - vertical three kinds of structures. Corresponds to the vertical section installed in the pipeline, the horizontal section and turning section. Vertical type to the height of the gas inlet axis shall prevail, the axis of the gas outlet height direction can be adjusted according to the actual installation requirements, which in practice can save 1 to 2 pipe on the pipe. The horizontal type is based on the horizontal axis of the gas inlet. The horizontal axis of the gas outlet can be arranged within ± 90 °. Horizontal - vertical horizontal gas inlet / outlet horizontal axis can be arbitrarily arranged within ± 180 °, the horizontal gas inlet / outlet height can be adjusted according to the actual needs of the installation, the practical application, but also can save on the pipeline 1 to 2 elbows. According to the gas flow setting, the liquid seal chamber is arranged behind the valve plate. The cross-sectional area of ​​any gas flow passage in the valve body is not to be less than the cross-sectional area of ​​the pipe. Because the liquid seal cavity is a nested structure that can be separated from up and down, the gas flow channel in the liquid seal cavity after the valve is closed is not the normal gas flow channel when the valve is opened, so that the valve body volume is greatly reduced. The number of liquid seal chamber can be any number of processes, usually 2 to 6 courses. The annular multi-layer separator corresponding to the upper and lower plates is also any number of layers, usually 2 to 6 layers. Liquid seal cavity design of the effective liquid seal height must be consistent with the corresponding gas media specifications, the required requirements. To gas, for example, must comply with the provisions of GB6222-2005 effective liquid seal height, that is effective liquid seal height of at least plus 5000Pa gas pressure calculation. Multi-pass liquid seal makes the actual injection height is greatly reduced, ensuring the effective seal height under the premise of reducing the quality of the valve operation. Sealant liquid used should be at room temperature and pressure is not volatile or volatile volatile chemical stability of the liquid, not with the gas barrier fluid medium and liquid chamber cavity base material reaction, and should have good flame retardancy. Common liquid seal fluid water and fluorine oil. If you choose a higher density of fluorine oil, you can further reduce the valve size. Liquid seal valve body wall thickness of not less than the corresponding installation of pipe wall thickness. The material of the valve body is the same as or better than that of the corresponding pipe. As the liquid seal cavity design in the valve body, maintenance or replacement is not convenient, therefore, constitute the liquid seal cavity inner tube, partition and other components of the material is better than the body material, such as the use of 304,316 or 316L, etc. Stainless steel, the thickness of each component should be greater than the body wall thickness. 5 Conclusion Liquid seal valve used to cut off the gas pipeline conveying air has many features. ①The use of independent liquid seal cavity, to avoid the use of the process, the valve seat within the sediment obstruct the valve plate sealing seat and the valve seat close to the gas medium leakage caused by leakage. ② In the liquid seal cavity can be used up and down the separation of the nested structure design, the formation of multi-process liquid seal, in a small space to ensure adequate liquid seal height, reducing the valve size and reduce the valve itself and the quality of the quality of operation. ③ The valve is suitable for installation in different parts of the pipeline, such as horizontal section, vertical section or elbow, to meet different design and installation requirements, especially for large-diameter gas pipelines and layout applications in a small space. ④ mechanical structure is simple, lower manufacturing costs. ⑤ low failure rate during operation, maintenance easy and convenient maintenance.