The three-piece all-inclusive ball valve relies on rotating the valve core to make the valve unblocked or blocked. Pneumatic ball valve switch is light, small in size, can be made into large diameter, reliable sealing, simple structure, convenient maintenance, sealing surface and spherical surface are often closed, not easy to be eroded by medium, and are widely used in all walks of life.
It belongs to the same type of valve as the plug valve, only its closing part is a sphere, and the sphere rotates around the valve body line to achieve opening and closing. flow direction.
The three-piece all-inclusive ball valve is mainly composed of the valve body, the ball, the opening and closing transmission structure, the support structure and the sealing structure. It is Ф808mm, the maximum working pressure is 5MPa, and the inner diameter of the valve body flange is Ф489mm. The yield of the valve body material is 275MPa, the strength is 485MPa, and the allowable stress is 121.69MPa.
Due to the large diameter of the valve, considering the casting factors and the difficulty of processing, the valve body is designed as a two-part valve body. Pressure relief device, when the pressure in the valve body cavity is abnormal, the pressure in the valve cavity can be released through the pressure relief safety valve to protect the safety of the valve body. At the same time, since the lower connecting pipe has to bear the weight of the ball transmitted by the tail rod, in order to prevent the upper valve body from being too deformed, a boss is added between it and the flange. This two-part valve body is lighter in weight than the one-piece valve body, and is more convenient to cast, machine and install.
The structure of valve seat seal combined seal, the primary metal seal can effectively prevent the damage of solid particles to the sealing surface; the secondary seal is the seal of the rubber O-ring, which has two functions, one is to wipe the surface of the sphere, prevent Its surface is damaged, on the other hand, it can ensure that the valve can meet the sealing requirements of "zero" leakage.