The advantages of the ball valve door and classification

Ball valve door advantages and classification of ball valves and plug valves is belong to one type of valve door, only its closure is a ball, the ball around the center line of valve body rotation to achieve the opening and closing a gate valve. Ball valve in the line is mainly used to do to cut off the door, distribution, and change the flow direction of medium. Fluid resistance is small, its resistance coefficient with section of equal length. Simple structure, small volume, light weight. Close and reliable, and the widespread use of plastic ball valve sealing surface of the door materials, sealing is good, have been widely used in the vacuum system. Easy to operate, open and close quickly, from open to close just rotate it 90 & deg; To facilitate remote control. Convenient maintenance, simple ball valve door structure, sealing ring, which generally remove replacement is more convenient. In full open or full close, sphere and valve seat sealing surface and the dielectric isolation, medium through, does not cause the valve sealing surface erosion. Applicability is wide and size from small to several millimeters, big to a few meters, from high vacuum to high pressure can be applied. Ball valve gate has been widely used in petroleum, chemical, power, papermaking, atomic energy, aviation, rockets and other departments, as well as People's Daily life. Ball valve door can be divided into the form of the structure: one gate, floating ball valve, ball valve gate ball is floating, under the effect of medium pressure, the fitness ball produce certain displacement and compression at the outlet seal surface, guarantee the outlet seal. Floating ball ball valve gate has simple structure, good sealing, but all spheres of work under medium load to export seal, therefore should consider to seal material can withstand sphere medium working load. In this structure, it is widely used in low pressure ball valve gate. Second, the fixed ball ball valve gate valve gate ball is fixed, does not produce mobile after compression. Fixed ball ball valve door with floating valve seat, after the medium pressure, the valve seat produced mobile, make the seal compression on the ball, to ensure the seal. Usually mounted on the upper and lower shaft with ball bearing, the operating torque is small, suitable for high pressure and large diameter of the valve gate. To reduce the number of gate ball valve operating torque and increase the reliability of the sealing, appeared in recent years, oil seal ball valve door, both between the sealing surface pressure note special lubricating oil, to form a layer of oil film, which increases the sealing, and reduce operating torque, suitable for high pressure large diameter ball valve gate. Three, elastic ball ball valve ball valve door is elastic sphere. Sphere and valve seat sealing ring is made of metal material sealing pressure is very big, relying on the pressure of the medium itself already could not reach the requirements of sealing, must exert external forces. The valve door is suitable for high temperature and high pressure medium. Elastic ball is on the lower end of the sphere wall open one elastic slot, and elasticity. When close the channel, with the valve rod wedge-shaped head make the ball up to open and close to achieve sealing pressure of the valve seat. Wedge head before you turn the sphere are released, the sphere then restore the original prototype, appear very small gap between the sphere and valve seat, can reduce the sealing surface friction and operating torque. Ball valve door according to the channel position can be divided into straight-through, three general formula and right Angle type. Two ball valves for distribution after the medium and the change of medium flow valve door series, http://www. nwfamen。 com/ProList/T15