It is by rotating the valve to make the valve unblocked or blocked. The ball valve switch is light, small in size, can be made into a large diameter, reliable sealing, simple structure, convenient maintenance, the sealing surface and the spherical surface are often closed, and are not easily eroded by the medium, and are widely used in various industries.
First, the opening process:
A. In the closed position, the ball is pressed against the valve seat by the mechanical pressure of the valve stem;
B. When the handwheel is turned counterclockwise, the valve stem moves in the opposite direction, and the angular plane at the bottom makes the ball disengage from the valve seat;
C. The valve stem continues to rise, and interacts with the guide pin in the spiral groove of the valve stem, so that the ball starts to rotate without friction;
D. Until it reaches the fully open position, the valve stem is lifted to the limit position, and the ball rotates to the fully open position.
Second, the closing process:
A. When closing, rotate the handwheel clockwise, the valve stem starts to descend and the ball leaves the valve seat and starts to rotate;
B. Continue to rotate the handwheel, the valve stem is acted by the guide pin embedded in the upper spiral groove, so that the valve stem and the sphere rotate 90° at the same time;
C. When it is about to close, the ball has rotated 90° without contacting the valve seat;
D. In the last few turns of the handwheel rotation, the angular plane at the bottom of the valve stem is mechanically wedged to press the ball, so that it is tightly pressed on the valve seat to achieve complete sealing.
