Plug valve is one of the earliest used valves with simple structure, fast opening and closing and low fluid resistance. Ordinary plug valves are sealed by the direct contact between the finished metal plug body and the valve body, which has the disadvantages of poor sealing, large opening and closing force and easy wear. They can only be used in low (not higher than 1 MPa) and small diameter (less than 100 mm). In order to expand the application range of plug valve, many new structures have been developed. Oil seal plug valve is the most important one. Special grease is injected from the top of the plug body between the taper hole of the valve body and the plug body to form an oil film to reduce the opening and closing torque and improve the sealing performance and service life. Its working pressure can reach 64 MPa, the maximum working temperature can reach 325℃, and the maximum diameter can reach 600 mm. The closing part of the plug valve is a cylinder with holes, which rotates around the axis perpendicular to the channel, so as to open and close the channel. Advantages of plug valve: 1. Easy for frequent operation, quick opening and closing; 2. Low fluid resistance; 3. Simple structure, relatively small volume, light weight and easy maintenance; 4. Good sealing performance; 5. The installation direction is unrestricted, the flow direction of media can be arbitrary; 6. No vibration and low noise. Classification of plug valves: 1. By structure: tight set plug valve, self-sealing plug valve, pressure balance plug valve and oil seal plug valve; 2. By channel: straight plug valve, three-way plug valve and four-way plug valve. The channel of plug valve has many forms. The common straight through type is mainly used to cut off the fluid; Three-way and four-way plug valve are suitable for fluid reversing.

平盖阀是一个滑动阀，其关闭部分是平行门。关闭部分可以是单栅极盘或具有支撑机构的双门盘。楔形到阀门的压力由作用在浮动楔或浮动阀座上的中型压力控制。如果是双楔形式栅极，则两个楔形之间的支撑机构可以补充这种压力。平板阀的特征：1。阀座座采用预紧力的O形圈密封件和浮动阀座椅结构，从而使平坦闸阀的入口和出口都密封在两个方向上。开口和关闭扭矩仅为普通阀的1/2。2.当完全打开时，通道是平稳且笔直的，电阻系数非常小，没有压力损失，简单清洁；3.采用具有自密封能力的填料结构，密封性能比普通石墨包装更可靠。另外，将油脂注入填料的密封表面，密封表面符合零泄漏标准。4.关闭扁平门阀时，它可以自动去除内部空腔中的高压以确保使用安全性； 5. Fully enclosed structure, good protection performance. Flat gate valve is divided into single gate plate and double gate plate. According to the connection mode, it can be divided into butt welded flat gate valve and flange flat gate valve. Features of butt welded flat gate valve: 1. Small fluid resistance and small scouring and erosion of sealing surface by medium; 2. Opening and closing is labor-saving; 3. The flow direction of the medium is unrestricted, no turbulence and no pressure reduction. 4. Simple shape, short structure length, good manufacturing technology and wide application range. Flange flat gate valve is stable and reliable when used in pipeline, Therefore, DERVOS recommends that flange flat gate valve could be used in high pressure pipeline. Features of flange type flat gate valve: 1. The sealing structure of flange flat gate valve is elastic with preload, and the upstream and downstream sealing seats are sealed at the same time. There is always face-to-face seal between the valve seat and the seal; 2. The valve seat has self-cleaning function and is not directly scoured by the air flow during the opening or closing of the valve. The valve seat is made of lubricated and non abrasive materials; 3. The problem of the valve actuator will not affect other parts of the valve, and the maintenance and replacement can be carried out without removing the valve; 4. When the flange flat gate valve is fully opened, the channel is smooth and straight, the flow resistance coefficient is very small, there is no pressure loss, and the pipeline can be cleaned by wool ball.

在中国2022年是虎年。它将不le's expectations that they could be as brave and strong as tigers and keep working hard. DERVOS Annual meeting of 2021 was held in the second working day after the Spring Festival holiday, which is also Valentine's Day, 14th Feb. In the morning, the heads of all departments made work reports. In the work reports, they reviewed the work achievements of the past year. At the same time, the Department's work objectives and work plans for the new year were formulated. Finally, Eric, our general manager summarized and planed the direction of struggle in 2022.The key word is pragmatic and development. Pragmatic means to work steadily, reduce trial and error costs, and carry out work with practical and feasible schemes. In the meantime, go from complexity to simplicity,result oriented, the final goal is to achieve the development. In the evening, the annual work summary came to an end and the annual dinner officially began. This was not only a good time for different departments to get together, but also an opportunity to win big prizes. DERVOS people work hard and also love life. We are grateful to the support of our business partners over the past year. We will continue to improve and provide partners with the most professional support and meticulous service.