High performance fluid control valve

摘要

A fluid control valve includes a valve body having a fluid passageway, a cage mounted in the fluid passageway and a valve plug assembly including a valve plug. The cage has a cage bore and defines one or more windows, a valve seat located below the windows and a flow control portion of the cage bore located between the valve seat and the windows. The flow control portion has an interior contour that varies in dimension as a function of distance from the valve seat. The flow control portion provides precise control in low flow conditions. The cage may further define a sealing lip located above the windows. The valve plug assembly may include a deformable sealing ring for engaging the sealing lip when the valve plug is in a closed position. The deformable sealing ring permits valve plug travel that is substantially free of sliding seal friction.