A gate valve is a wedge disc for opening and closing. The movement direction of the brake is required to be perpendicular to the direction of the fluid. It can be opened and closed completely, and cannot be adjusted or throttled. The gate valve is sealed by the contact between the valve seat and the gate. Usually, the metal material is sealed and welded to improve the wear resistance. The gate is divided into rigid and elastic gates and is widely used in chemical, petroleum, light industry, hospitals, environmental protection, etc.
How does a gate valve work? The opening and closing disc of the gate valve is the wedge disc, which has two sealing surfaces. The most commonly used mode is that the two sealing surfaces of the gate valve form a wedge. The wedge angle depends on the valve parameters, which is usually 5°, and is 2°52' when the medium temperature is not high. The gate of the wedge gate valve can form a whole, which is called a rigid gate. It is possible to manufacture gates that can produce slight deformation so as to improve the manufacturability, and compensate for the deviation of the sealing surface angle during processing. This kind of gate is called an elastic gate. After the gate valve is closed, the sealing surface can only be sealed by the pressure of the medium. In other words, according to the media pressure, the sealing surface of the gate can be pushed into the other side to ensure the sealing of the sealing surface, which is called self-sealing. Most gate valves adopt the method of forced sealing.
1. The flow resistance is small. The media channel inside the valve is straight, and the flow resistance is small.
2. It is easier for it to do the opening action. Because compared with the shut-off valve, the movement direction of the gate valve is perpendicular to the direction of the medium flow, whether it is open or closed.
3. High and long opening and closing time. The opening and closing stroke of the gate is relatively large, and the elevator is carried out by screws.
4. Water hammer is not easy to occur.
5. The two sides of the channel are symmetrical, and the medium can flow in any direction from both sides, which is convenient for installation.
6. The structure length (the distance between the two connecting end faces of the system shell) is small.
7. The gate valve has simple body shape, short structure, good manufacturing technology and wide application range.
8. The gate valve boasts compact structure, good valve rigidity, soft channel, small flow resistance, long sealing surface between stainless steel and hard alloy, long service life, PTFE packing, reliable sealing, light and flexible operation.