Patent ID: 6536472
Filing Date: 2003-03-25
Classification: F16K,Y10T

Abstract:
A fluid control valve comprising:a valve body having a fluid passageway; a cage mounted in said fluid passageway, said cage including a generally cylindrical wall, a cage bore having an axis, said cage defining one or more windows, a valve seat located below said one or more windows and a flow control portion of the cage bore located between said valve seat and said windows, the flow control portion having an interior contour that varies in dimension as a function of distance from said valve seat; and a valve plug assembly including a valve plug that is axially slidable in the cage bore and is guided by said cage between a closed position in engagement with said valve seat, a partially open position wherein fluid flow is determined by a spacing between said valve plug and the flow control portion of the cage bore, and a more open position wherein fluid flow is determined by said windows and by said spacing, wherein said valve plug comprises a cylindrical section that defines a spacing between said valve plug and the flow control portion of the cage bore, and an annular expansion groove above said cylindrical section configured to facilitate low pressure recovery for reduced noise in low flow applications.