Perforated valve trim and method for producing the same

Claim 1

Perforated valve trim for the control of fluid flow as part of and between a cylindrical valve plug slidingly engaged in a cylindrical valve orifice comprising: a vertical stack of horizontal plates, each plate being subdivided into first and second wedge shaped segments, at least one first segment per plate having one or more slotted openings extending in radial fashion throughout a portion of the radial width of said plates, thereby providing access for fluid in the radial direction, at least one second segment per plate having at least one large, vertical flow passage opening therethrough, providing a communicating passage for fluid in the vertical direction; said large vertical opening having a cross-sectional area exceeding the combined cross-sectional areas of the slotted openings of said at least one first segment, all stack plates being angularly displaced with respect to each other about the vertical stack axis, so that in successive stack plates the large opening overlaps the segments encompassing the slotted openings; whereby are provided a number of separate fluid passages extending through said stack in vertical direction providing access for and communicating with restrictive fluid passages formed by the width of each of said slotted openings and the height of each plate in the horizontal direction.