Knife gate valve is a kind of valve used to control fluid medium, and its opening and closing principle is realized by moving the blade (or gate) inside the valve up and down.
Sea shield knife gate valve
When the knife gate valve is closed, the blade will move downward to isolate the fluid and prevent it from passing through the valve. On the contrary, when the knife gate valve is opened, the blade will move upward and the fluid will pass through the valve unimpeded.
The movement of the blade can be controlled by manual, electric, hydraulic and pneumatic methods. Manual control usually adopts handwheel or handle, electric control needs the cooperation of motor and controller, and hydraulic or pneumatic control needs the cooperation of hydraulic or pneumatic system.
In a word, the switching principle of knife gate valve is to control the circulation of medium by moving the blade up and down in the valve. Different control methods can realize different degrees of automation and remote control.
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