The four basic functions of the straight-through valve

- May 31, 2018-

First, cut off and release media

This is the most basic function of the valve. Usually, the flow path is a straight-through valve with a small flow resistance.

Down-closed valves (stop valves, plunger valves) are less preferred due to the tortuous flow path and higher flow resistance than other valves. Where higher fluid resistance is permitted, closed valves may be used.

Second, control the flow

A valve that is easy to adjust the flow rate is usually selected as the control flow. A closed down valve, such as a shutoff valve, is suitable for this purpose because of the proportional relationship between its seat size and the stroke of the closure.

Rotary valves (plug valves, butterfly valves, ball valves) and flexible valve body valves (pinch valves, diaphragm valves) can also be used for throttling control, but they are usually only suitable for limited valve sizes.

The gate valve is a cross-cut movement of the circular valve seat with a disk-shaped gate. It can control the flow only when it is close to the closed position, so it is usually not used for flow control.

Third, commutation and diversion

According to commutation diversion needs, this valve can have three or more channels. Plug valves and ball valves are more suitable for this purpose. Therefore, most of the valves used for commutation and diversion have selected one of these types of valves.

However, in some cases, other types of valves may also be used for commutation diverting as long as two or more valves are properly connected to each other.

IV. Medium with suspended particles

When the medium contains suspended particles, it is most suitable to use a sliding valve with a wiper action along its sealing surface.

If the closing member's back and forth movement of the valve seat is vertical, it is possible to hold the particles, and therefore this valve is only suitable for a substantially clean medium unless the material of the sealing surface can allow embedded particles. Ball valve and plug valve wipe the sealing surface in the process of opening and closing, it is suitable for use in media with suspended particles.

After installation of the valve, it is recommended to install anti-retractor, rubber joints to ensure that your valve is stable and prolong life. More reflect your valve price.