Pneumatic ball valves are evolved from plug valves. It has the same 90 degree rotation, except that the plug body is a sphere with a circular through hole or passage through its axis. The ratio of the spherical surface to the passage opening should be such that when the ball is rotated 90 degrees, the spherical surface should be entirely present at the inlet and outlet to intercept the flow.
working principle
The pneumatic ball valve only needs to be rotated by a pneumatic actuator with a gas source rotated by 90 degrees and a small turning torque to close tightly. The fully equal valve body cavity provides a small, straight-through flow path for the medium. Ball valves are generally considered to be the most suitable for opening and closing, but recent developments have designed ball valves to throt and control flow. The main features of the ball valve are its compact structure, easy operation and maintenance, suitable for general working media such as water, solvent, acid and natural gas, and also suitable for medium with harsh working conditions such as oxygen, hydrogen peroxide, methane and ethylene. The ball valve body may be integral or combined.
The practical effect of pneumatic ball valve
The pneumatic ball valve works by rotating the valve plug to make the valve unblocked or occluded. The pneumatic ball valve switch is light in weight, small in size, can be made into a large diameter, reliable in sealing, simple in structure, convenient in maintenance, and the sealing surface and the spherical surface are often closed. The non-pneumatic ball valve is easily eroded by the medium and is widely used in various industries. The pneumatic ball valve and the plug valve are the same type of valve, only the closing member of which is a ball, and the ball rotates around the center line of the valve body to open and close a valve.
advantage
Pneumatic ball valves are mainly used in pipelines to cut off quickly, distribute and change the flow direction of the medium. Pneumatic ball valve is a new type of valve widely used in recent years. It has the following advantages: 1. The fluid resistance is small, and its resistance coefficient is equal to the pipe length of the same length. 2. Simple structure, small size and light weight. 3. Close and reliable, the sealing surface material of the ball valve is widely used in plastics and has good sealing performance, and has been widely used in vacuum systems. 4. It is easy to operate, and it can be opened and closed quickly. It can be rotated by 90° from full opening to full closing, which is convenient for long-distance control. 5. Convenient maintenance, pneumatic ball valve structure is simple, the sealing ring is generally active, and it is convenient to disassemble and replace. 6. When fully open or fully closed, the sealing surface of the ball and the valve seat is isolated from the medium. When the medium passes, it will not cause erosion of the sealing surface of the valve. 7. Wide range of applications, from small to a few millimeters, up to a few meters, from high vacuum to high pressure can be applied. 8. Because the power source of the pneumatic ball valve is gas, it is generally 0.2-0.8MPa pressure, which is relatively safe. If the pneumatic ball valve leaks, the gas can be directly discharged compared with the hydraulic and electric motors, and it has no pollution to the environment and has high safety. 9. Compared with manual and turbo rotating ball valves, pneumatic ball valves can be configured with large diameters. (Manual and turbo rotating ball valves are generally below DN300 caliber, pneumatic ball valves can currently reach DN1200 caliber.) Pneumatic ball valves have been widely used in petroleum and chemical industries. , power generation, paper, atomic energy, aviation, rockets and other departments, as well as people's daily lives.