Are there any regulations regarding not using ball valves in a partially open position?
Thread Content
Are there any regulations regarding not using ball valves in a partially open position? What standards?
When a soft-sealed ball valve is operated in a half-open or half-closed position, the ball will compress and deform the sealing seat, resulting in a failure to achieve sealing.
Ignore whatever standards he has; it’s enough to know that you can’t operate in that way
There should be no regulations; the manufacturer’s requirements should be sufficient
This post was last edited by qugd on 2022-9-3 at 13:02. Due to their structural characteristics, ball valves should be operated in either the fully open or fully closed position; other operating positions are not suitable. First, the sealing performance of the valve must be maintained; second, it is necessary to prevent the valve core from being deformed or damaged by the action of the medium. The operating procedures for ball valves are also established based on the structural characteristics of the valves. Also, since that position was designed as a ball valve, it must have been taken into account that ball valves are generally operated in an all-open or all-closed state. If some degree of opening adjustment is required, then valves in other suitable forms that allow for such adjustment should be designed.
Considering the characteristics of the product itself, being half-open affects its performance. As for the relevant specifications, they will be there. . . . Ball valves are available in normally open and normally closed types.
Ball valves should not be used at a partial open position; this is a requirement set by valve manufacturers for soft-sealed ball valves, rather than a standard. In the semi-open position, soft-sealed ball valves experience uneven stress on their sealing surfaces, which leads to uneven deformation of these surfaces and affects the valve’s ability to open and close. Therefore, it should not remain in a semi-open state for long periods.
Ball valves are designed to be used for full opening and closing; if there is a need for partial restriction, then a different type of valve should be used. It is indeed possible to operate them at a partial open position in order to limit flow, but this will lead to internal leakage over time