What is the purpose of a valve and where is it used?

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A valve is a pipeline accessory. It is a device used to change the channel cross section and the direction of medium flow, and control the flow of the conveyed medium. Specifically, valves have the following uses:

(1) Connecting or cutting off the medium in the pipeline. Such as gate valves, globe valves, ball valves, plug valves, diaphragm valves, butterfly valves, etc.

(2)  Regulate and control the flow and pressure of the medium in the pipeline. Such as throttle valve, regulating valve, pressure reducing valve, safety valve, etc.

(3)  Change the direction of medium flow in the pipeline. Such as distribution valve, three-way cock, three-way or four-way ball valve, etc.

(4) Prevent the backflow of media in the pipeline. Such as various check valves, bottom valves, etc. of different structures.

(5) Separation medium. Such as steam traps, air traps of various structures, etc.

(6)   Indicate and adjust the liquid level. Such as liquid level indicator, liquid level regulator, etc. (7) Other special purposes.

 Such as temperature regulating valve, overcurrent protection emergency shut-off valve, etc. Among the above-mentioned various general valves, the number of valves used to connect and cut off the flow of media in pipelines accounts for about 80% of the total number of valves.