In the piping system, the valve is the control element, just like the human hand, so whether in life or in all walks of life, its importance is self-evident.

What are its features? How is it installed? What do the common markings mean? When there is a malfunction, how to repair it? The most important 4 aspects of the next, and everyone to understand!

NO1 Cutoff and open media

Valves with straight-through flow paths have low flow resistance and are usually chosen as valves for shut-off and open media.

    Downward closing type valve (globe valve, plunger valve) due to its flow path zigzag, flow resistance is higher than other valves, so less selection. In allowing a higher flow resistance of the occasion, can choose to close the valve.

NO2 Control flow

Valves that are easy to regulate flow are usually selected for flow control. Downward closing valves (e.g., globe valves) are suitable for this purpose because of the proportional relationship between the seat size and the travel of the closing member.

    Rotary valves (plug valves, butterfly valves, ball valves) and flexure body type valves (clamp valves, diaphragm valves) can also be used for throttling control, but are usually only applicable within a limited range of valve sizes.

    Gate valve is a disc-shaped gate to the circular valve seat mouth to do cross-cutting movement, it is only close to the closed position, can better control the flow, so usually not used for flow control.

NO3 commutation shunt

Depending on the need for commutation and diversion, such valves may have three or more passages. Plug valves and ball valves are more suitable for this purpose, and therefore one of these types of valves is selected for most of the valves used for commutation.

    In some cases, however, other types of valves, as long as two or more valves are properly interconnected, can also be used for commutation.

NO4 Media with suspended particles

Valves in which the sliding of the closing member along the sealing surface has a wiping action are best suited when the medium contains suspended particles.

    If the back and forth movement of the closing member to the seat is vertical, then it may entrap particles, so this valve unless the sealing surface material can allow embedded particles, or only for basic clean media. Ball valves and plug valves in the opening and closing process of the sealing surface are wiping effect, so it is suitable for use in the medium with suspended particles.