Orbital ball valve
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Today, the management issued a document stating that ball valves must be opened and closed completely! Please explain! ! !
How does it work? Its working principle is as follows: During the opening process of the orbital ball valve, 1 in the closed position, the ball is under mechanical pressure from the valve stem and is pressed tightly against the valve seat. 2 When the handwheel is turned counterclockwise, the valve stem moves in the opposite direction; its angled bottom surface causes the ball to disengage from the valve seat. The 3 valve stem continues to rise and interacts with the guide pin in the valve stem’s helical groove, causing the ball to begin rotating frictionlessly. 4 Until it reaches the fully open position, the valve stem is lifted to its extreme position, and the ball rotates to the fully open position. Closing process of the orbital ball valve: 1. To close it, rotate the handwheel clockwise; the valve stem begins to descend, causing the ball to move away from the valve seat and start rotating. 2. Continue to turn the handwheel; the valve stem, acted upon by the guide pins embedded in the helical grooves on it, causes both the valve stem and the ball to rotate 90° at the same time. 3 By the time it was about to be shut off, the sphere had rotated 90° without making contact with the valve seat. In the last few turns of the handwheel, the angular surface at the bottom of the valve stem mechanically presses against the ball, forcing it to fit tightly against the valve seat and achieving a complete seal.
I’ll also use Baidu; please answer me directly. Is it necessary to turn everything on or off? If not, what are the potential risks?
Yes, if that’s not the case, over time the valve body will be worn out by sand erosion, resulting in leaks when it is closed.
Orbit ball valves are generally used in applications where frequent opening and closing are required and high sealing standards are necessary; they enable complete isolation of flow. They are not suitable for use under conditions involving variable flow rates. To ensure reliable isolation, they must be kept either fully open or fully closed in order to avoid wear
Thank you, I’ve learned some new things again
Ball valves are usually only available as on/off valves, with the exception of V-ball valves; therefore, most ball valves can only be in a fully open or fully closed position, and cannot be held in a partially open state.