| 摘要 |
An apparatus and method are provided for reducing the torque required to reposition a valve member of a ball valve, by maintaining continuous fluid communication between a cavity surrounding the valve member and an upstream flow-through end of a valve body of the ball valve, regardless of the alignment of the valve member with respect to the upstream flow-through end of the valve body. The continuous fluid communication is provided by a seal bypass passage that is defined alternatively, by the valve body, an upstream seal, or by one or more holes passing through an outer wall of the valve member that faces toward the upstream flow-through end of the valve body when the valve member is in the closed position.
|
