How Lined Ball Valve Works

Publish Time: 09/12 2025 Author: Site Editor Visit: 1

I. Opening Process
1. In the closed position, the ball is pressed against the valve seat by the mechanical pressure of the Lined Ball Valve stem.
2. When the handwheel is turned counterclockwise, the valve stem moves in the opposite direction, and the angled flat surface on its bottom disengages the ball from the valve seat.
3. The valve stem continues to rise and interacts with the guide pin in the spiral groove of the valve stem, causing the ball to begin to rotate frictionlessly.
4. When the valve reaches the fully open position, the valve stem rises to its limit, and the ball rotates to the fully open position.
II. Closing Process
1. To close, turn the handwheel clockwise, and the valve stem begins to descend, causing the ball to leave the valve seat and begin to rotate.
2. Continue turning the handwheel. The valve stem, acting upon the guide pin embedded in the spiral groove, rotates both the valve stem and the ball 90° simultaneously.
3. When the valve is nearly closed, the ball has already rotated 90° without contacting the valve seat. 4. During the last few turns of the handwheel, the angular plane at the bottom of the valve stem mechanically wedges against the pressure ball, pressing it tightly against the valve seat to achieve complete sealing.