The ball valve and the plug valve are the same type of valve, only the closing part is a ball, and the ball rotates around the center line of the valve body to achieve an open and closed valve.
The ball valve is mainly used for pipe cutting, distribution and changing the flow direction of the medium. Electric vacuum ball valve is a new type of valve widely used in recent years and has the following advantages
1. The fluid resistance is small, and the resistance coefficient is equal to the pipe section of the same length.
2. Simple structure, small size and light weight.
3. It is tight and reliable. At present, the ball valve sealing material is widely used in plastics and has good sealing performance. It is also widely used in vacuum systems .
4. Convenient operation, fast switching, 90° rotation from fully open to fully closed, and convenient remote control.
5. Convenient maintenance, simple ball valve structure, general movement of the sealing ring, easy disassembly and replacement.
6. When fully open or fully closed, the sealing surface of the ball and the valve seat is isolated from the medium, and the medium will not cause erosion of the valve sealing surface when the medium passes.
7. A wide range of applications, from small to several millimeters, from large to several meters, from high vacuum to high pressure can be applied.
Ball valves can be divided into:
1. Floating ball valve.
The ball of the ball valve floats. Under the action of the medium pressure, the ball can produce a certain displacement and press on the sealing surface of the outlet end to ensure the sealing of the outlet end.
2. Fixed ball valve.
The ball of the ball valve is fixed and does not move after being pressed. The fixed ball valve has a floating seat. After receiving the pressure of the medium, the seat moves to press the sealing ring on the sphere to ensure sealing. Generally, the bearings are installed on the upper and lower shafts of the sphere, and the operating torque is small, which is suitable for high pressure and large diameter valves.
3. Elastic ball valve.
The ball of the ball valve is elastic. The ball and valve seat sealing ring are made of metal materials, and the specific pressure of the sealing is relatively large. The pressure of the medium itself cannot meet the sealing requirements, and external force should be applied. The valve is suitable for high temperature and high pressure media.