A、 start-up process

1. In the closed position, the ball is pressed tightly against the valve seat by the mechanical pressure exerted by the valve stem.

When the handwheel is turned counterclockwise, the valve stem moves in the opposite direction, and its bottom angular plane causes the ball to detach from the valve seat.

3. The valve stem continues to lift and interacts with the guide pin in the spiral groove of the valve stem, causing the ball to start rotating frictionlessly.

4. 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.

B、 Closing process

When closing, rotate the handwheel clockwise and the valve stem begins to descend, causing the ball to move away from the valve seat and begin to rotate.

2. Continue to rotate the handwheel, and the valve stem is acted upon by the guide pin embedded in its spiral groove, causing both the valve stem and the ball to rotate 90 ° simultaneously.

When it was about to close, the sphere had already rotated 90 degrees without contact with the valve seat.

During the last few turns of the handwheel, the angular plane at the bottom of the valve stem mechanically wedges and presses the ball tightly against the valve seat, achieving a sealing effect.