With the progress of The Times, many fields of our country have obtained rapid development, in this background, the development of China's chemical industry has made some progress. Used in specific chemical piping design work valve type is various, therefore, also increased the difficulty of the valve selection work. In this context, the corresponding personnel in the selection of valves should pay attention to the valve structure, principle, performance and other aspects, in the characteristics of a certain understanding of the careful choice. So, this paper is focus on the characteristics of the valve.
1. Gate Valve
At present, gate valve is a very common type of valve in the design of chemical pipeline in China. Through the analysis of relevant research results, it can be found that gate valve is usually less affected by pressure and temperature in the working process, and when the liquid flows through the valve, the direction of flow will not change greatly, and its resistance to medium is very small. At the same time, the valve still has a series of disadvantages, such as the time it takes to open and close a gate valve to use, and the fact that the fluid flowing through it can easily erode its surface, which limits its application.
2. Globe Valve
When carrying out specific chemical pipeline design work, globe valve is also a commonly used valve type. Currently, in this field, the valve is mainly applied to the outlet position of the pump or the upstream position of the regulating valve. The globe valve can be further divided into straight-through globe valve, angular globe valve and y-type globe valve, which are common globe valves. Cut-off valve in a certain extent, improved the gate of the shortcomings, more wear-resistant than gate valves, it is also easier to maintenance and management of related personnel, but need to pay attention to make the valve in use process also has limitations, it rings at work is a must to flow through it smart one-way flow, and it is difficult to a long time to keep the seal for long hours.
3. Check Valve
Check valve also is what we usually call one-way valve, as the name implies, when the medium flows between them is only allowed to flow in one direction, the characteristics of it can make it well to prevent reverse flow of medium plays an important role, on the basis of this can well realize the purpose of prevent damage of chemical pipes. At the same time, its unidirectional characteristics will cause greater restrictions on its application, So it can only be used as an auxiliary valve device to prevent medium counterflow, and cannot be more widely used. The more common check valve mainly includes swing check valve, lift check valve and ball check valve three types, among which swing check valve is a more commonly used one.