Working principle
Using a plug body with a through-hole as the opening and closing component, the plug body rotates with the valve stem to achieve the opening and closing action. The plug body is mostly conical (also cylindrical), which cooperates with the conical hole surface of the valve body to form a sealing pair. When the channel on the plug is aligned with the valve body channel, fluid can flow; If it is not on time, fluid flow will be blocked.
classification
1. According to the structure
Tightening plug valve: usually used for low-pressure through pipelines, the sealing performance depends on the fit between the plug and the plug body. The cover is tightened by tightening the lower nut, generally used for PN ≤ 0.6Mpa.
Packing plug valve: The plug and plug body are sealed by compressing the packing, with a packing cover. The plug does not need to extend out of the valve body, reducing the leakage path. It is widely used for pressures with PN ≤ 1Mpa.
Self sealing plug valve: The plug and plug body are compressed and sealed by the pressure of the medium itself. The plug head extends upward from the body, and the medium enters the plug head through the inlet hole and is compressed upward. It is generally used for air media.
Oil filled plug valve: using forced lubrication, an oil film is formed between the plug and the sealing surface of the plug body, with good sealing performance, easy opening and closing, and preventing damage to the sealing surface.
2. By channel form
Divided through plug valve: With a simple structure, it is used to cut off fluids. By rotating the plug body and valve body to align or offset the channel, it can achieve conduction or blockage.
Three way plug valve: It can achieve control of medium diversion or merging. The rotating plug body guides the fluid to different channel outlets, changing the direction of medium flow.
Four way plug valve: suitable for more complex fluid control systems, with more channel options than three-way to meet more complex medium distribution and flow control requirements.