What should chemical plants pay attention to when selecting stainless steel valves?

Published on:

2021-01-27

The criteria for stainless steel valves in the chemical industry: the flow path is a straight-through valve, and its flow resistance is relatively small. Generally, it is used as a valve for shutting off and closing the medium; a valve that is easy to adjust the flow rate is used to control the flow rate; the plug valve and ball valve are more practical for replacement It is used for diversion; the valve with wiping effect along the sliding of the cover of the open piece is applicable to the medium with suspended particles.

　　 1, the valve flow path used to cut off and close the medium is a straight-through valve, and its flow resistance is small. Generally, the valve used to cut off and close the medium is selected. The downward-closed valve (stop valve, plunger valve) is seldom used because of its large flow path and higher flow resistance than other valves. In places where there is a higher flow resistance, closed valves can be used.

　　 2. Valves for controlling the flow rate generally choose the valve that is easy to adjust the flow rate for controlling the flow rate. A downward closing valve (such as a shut-off valve) is suitable for this purpose because of the inverse relationship between the size of its valve seat and the distance of the opening. Wrapped valves (cock valves, butterfly valves, ball valves) and flex-body valves (pinch valves, barrier valves) can also be used for diet control, but they are generally only practical in the scope of unlimited valve diameters. The gate valve uses a disc-shaped gate to cross-cut the circular valve seat port. As long as it is on the verge of opening, it can better control the flow, so it is generally not necessary to control the flow.

　　 3. Valves used for reversing and shunting can have three or more channels according to the requirements of reversing and shunting. Plug valves and ball valves are more practical for this method. Therefore, most of the valves used for reversing and splitting use one of the plug valves and ball valves. However, in some situations, other types of valves only need to be properly connected to each other with two or more valves, and they can also be used for reversing and shunting.

　　4. Valves for medium with suspended particles When there are suspended particles in the medium, it is actually used to adopt a valve with a wiping effect on the sliding of the open part along the dense book cover. If the opening piece is vertical to the one-way movement of the valve seat, if it can hold the particles, this kind of valve can allow embedded particles in addition to the secret book cover material, or it is not only used in fundamentally clean media. Ball valves, cock valves, and butterfly valves have a wiping effect on the secret book cover during the opening and closing process, so they are suitable for use in media with suspended particles.