Structure and function of pneumatic stainless steel ball valve
更新时间:2018.07.20
I. floating pneumatic v-type ball valve the ball of stainless steel pneumatic ball valve is floating. Under the action of medium pressure, the ball can generate a certain displacement and press tightly on the sealing surface of the outlet end to ensure that the outlet end is sealed. The floating pneumatic v-type ball valve is simple in structure and has good sealing performance. However, the ball bears the load of working medium and all the load of working medium is passed to the outlet seal ring. This structure is widely used in low and middle pressure ball valves. Fixed ball pneumatic ball valve the ball of stainless steel pneumatic ball valve is fixed and does not move after pressure. Fixed ball valve with floating seat, after the medium pressure, the seat moves, so that the sealing ring tightly pressed on the ball to ensure the sealing. Bearings are usually mounted on the upper and lower shafts of the ball with small operating torque for high pressure and large bore valves. In order to reduce the operating torque of pneumatic ball valve and increase the reliability of sealing, oil seal ball valve has appeared in recent years. It is not only used to fill special lubricating oil between the sealing surface to form a layer of oil film, which not only enhances the sealing performance, but also reduces the operating torque, and is more suitable for high pressure and large-caliber ball valve. The ball of the pneumatic ball valve is elastic. The ball and seat seal ring are made of metal material, and the sealing pressure is very high. The pressure of the medium itself cannot meet the requirements of sealing, so external force must be applied. This valve is suitable for high temperature and high pressure medium. The elastic sphere is obtained by opening an elastic groove at the lower end of the inner wall of the sphere. When closing the channel, use the wedge of the stem to make the ball open and the seat tight to seal. Before rotating the ball, loosen the wedge head, and the ball will return to its original shape, so that there is a small gap between the ball and the seat, which can reduce the friction and operating torque of the sealing surface. Pneumatic V ball valves can be divided into straight, three - way and right - Angle valves according to their channel position. The latter two ball valves are used to distribute the medium and change the direction of the medium.