| 摘要 |
A short stroke flow control device or valve which is adapted to provide velocity control trim in a short stroke. The valve constructed in accordance with the present invention comprises multiple disk stacks or cages which are separated from each other by intervening spacers, and are placed axially in a valve gallery clamped between a seat ring and bonnet of the valve. The fluid passageways in the cages are throttled in a controlled manner by a plug which defines multiple throttling elements or plug lobes, the number of plug lobes defined by the plug preferably being equal to the number of cages included in the valve. The plug lobes of the plug control the flow of fluid through the disk stacks or cages in tandem. All of the throttling elements or plug lobes of the plug, with the possible exception of the plug lobe which contacts the seat ring for closure, is larger in diameter than the remainder of the plug and has at least one kidney bean shaped flow passage extending therethrough. The flow area of such flow passages in the plug lobes is designed to satisfy prescribed seat bore velocity criteria. |
