The full-bore top-mounted eccentric semi-ball valve is mainly composed of a valve body, a ball, a ball crown, a valve seat, a sealing ring, a valve stem, a packing and a drive device. Its working principle is mainly to drive the valve stem to rotate through the actuator, and the valve stem drives the ball to rotate 90 degrees to realize the opening and closing of the valve.
Product structure features
The valve body adopts an integrated full-diameter structure design, which is compact and has a large flow area. The flow resistance after full opening is very small, which is basically equivalent to the pipeline, and the medium is not easy to deposit in the valve box.
The double eccentric wedge tightening principle is adopted. The valve sealing pair only contacts in the closed position. Due to the effect of eccentric rotation, the sealing pairs do not contact and have no friction during the opening and closing process. The operating torque is light. When the valve area is closed, it will be closed more and more tightly, and the forced sealing is realized, so that the valve can achieve good sealing performance and extend the service life of the valve at the same time.
After the valve is fully opened, the ball crown is hidden on one side of the inner cavity of the valve body, which is not easy to be directly washed by the medium, so that the sealing surface of the ball crown is well protected. The edge of the ball crown adopts a scraper structure design, which can clean the dirt around the valve seat sealing surface when closed, and has strong cutting ability.
The movable valve seat structure is adopted, and an adjustment device is installed inside. When the valve seal pair is worn after a period of use, the warning force between the valve seat and the ball seal pair can be readjusted through the adjustment device to restore its sealing ability.
The valve can bear pressure in both directions without any requirements on the flow direction of the medium, and the forward and reverse pressure bearing capacity can reach 1:1, which increases the application range of the valve.
With the top-mounted structure design, when the valve needs to be repaired, the valve body does not need to be removed from the pipeline. Only the valve cover needs to be removed to maintain and service the valve stem, ball, ball crown, sealing ring and other parts in the valve box, which greatly improves the convenience of maintenance and reduces the cost of maintenance.