Stainless steel manual ball valve and gate valve are the same type of valve, the difference is that the closure is a sphere, and the sphere rotates around the center line of the valve body to reach an open and closed valve. Ball valves are mainly used for blocking, distributing and changing the moving direction of the medium in the pipeline. Stainless steel manual ball valve is a relatively new type of ball valve. It has some advantages unique to its own structure, such as no friction in the switch, not easy to wear the seal, and small opening and closing torque. This reduces the size of the fitted actuator. Equipped with multi-reversal electric actuators, it can realize the adjustment and tight interception of the medium. It is widely used in petroleum, chemical, urban water supply and drainage and other working conditions that require strict blocking.
(1) Friction-free opening and closing: completely solve the problem that the traditional valve affects the sealing due to the friction between the sealing surfaces.
(2) Top-loading structure: The valves installed on the pipeline can be directly inspected and repaired online, which can effectively reduce installation and parking and reduce costs. Manual ball valves should generally be installed horizontally in the pipeline.
(3) Single valve seat design: eliminates the problem that the medium in the cavity of the valve affects the safety of operation due to abnormal pressure increase.
(4) Low torque design: The valve stem with special structure design can easily open and close the valve with only a small handle.
(5) Wedge-shaped sealing structure: the valve is sealed by the mechanical force supplied by the valve stem, which presses the ball wedge onto the valve seat to seal, so that the sealing performance of the valve is not affected by the change of the pressure difference of the pipeline, and the sealing function is under various working conditions. All are guaranteed.
(6) The self-cleaning structure of the sealing surface, when the sphere tilts away from the valve seat, the fluid in the pipeline passes evenly along the sphere sealing surface at 360°, which not only eliminates the local scouring of the valve seat by the high-speed fluid, but also washes away the sealing surface. On the accumulation, to achieve the purpose of self-cleaning.
The working principle of stainless steel manual ball valve: stainless ball valve relies on rotating the valve core to dredge or block the valve. The ball valve is easy to switch, small in size, can be made into a large diameter, reliable in sealing, simple in structure, and convenient in repair.
(1) Open process
In the closed position, the ball is pressed on the valve seat by the mechanical pressure effect of the valve stem. When the handwheel is rolled counterclockwise, the valve stem moves in the opposite direction. Lift, and interact with the guide pin in the spiral groove of the valve stem, so that the ball starts to rotate without friction until it reaches the full open position, the valve stem is lifted to the limit position, and the ball rotates to the full open position.
(2) closed process
When closed, rotate the handwheel clockwise, the stem of the manual ball valve begins to descend and the ball is separated from the valve seat and begins to rotate; if the handwheel is continuously rotated, the stem is affected by the guide pin embedded in the upper spiral groove, so that the stem and the ball At the same time, it rotates 90°. When it is about to close, the ball has rotated 90° without contacting the valve seat. During the last few turns of the handwheel, the angular flat at the bottom of the valve stem mechanically wedges the ball to press it tightly against the valve seat to achieve a complete seal.