A valve is a pipe attachment. It is used to change the channel section and the direction of medium flow, control the flow of the medium of a device. Specifically, valves have the following uses:
(1) Connect or cut off the medium in the pipeline. Such as gate valve, globe valve, ball valve, plug valve, diaphragm valve, butterfly valve, etc.
(2) Adjust and control the flow and pressure of the medium in the pipeline. Such as throttle valve, regulating valve, pressure reducing valve, safety valve and so on.
(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 media flow back in the pipeline. Such as a variety of different structures of check valves, bottom valves, etc.
(5) separation medium. Such as a variety of different structures of steam traps, air traps, etc.
(6) Indicate and adjust the liquid level height. Such as liquid level indicator, liquid level regulator, etc.
(7) Other special purposes. Such as temperature control valve, over - current protection emergency cut - off valve.
Among the various general valves mentioned above, the valves used to connect and cut off the flow of the medium in the pipeline account for about 80% of the total number of all valves.
