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A guided control valve comprising a vapor recovery area that encourages collapse of vapor bubbles. In a cage-guided valve, a seal comprising inner and outer members reduces flow through a radial clearance between a plug and a cage. The vapor recovery area is positioned below the seal and above a sea

A guided control valve comprising a vapor recovery area that encourages collapse of vapor bubbles. In a cage-guided valve, a seal comprising inner and outer members reduces flow through a radial clearance between a plug and a cage. The vapor recovery area is positioned below the seal and above a seat interacting with the plug. The vapor recovery area encourages collapse of vapor bubbles to reduce damage to the valve trim.

대표청구항 ▼

1. A globe control valve comprising a plug movably aligned in a cage to contact a seat to close the valve, wherein the cage includes a cage wall, the improvement comprising a pressure recovery area between the plug and the cage, wherein the plug includes a recessed portion with at least one wall in

1. A globe control valve comprising a plug movably aligned in a cage to contact a seat to close the valve, wherein the cage includes a cage wall, the improvement comprising a pressure recovery area between the plug and the cage, wherein the plug includes a recessed portion with at least one wall in the recessed portion substantially parallel to the cage wall, and the pressure recovery area is substantially defined by the area between the cage wall and the recessed portion. 2. The globe control valve of claim 1, wherein the pressure recovery area is a gallery. 3. The globe control valve of claim 1, wherein the pressure recovery area is positioned above the seat. 4. The globe control valve of claim 1, wherein the plug and the cage define a radial clearance and the improvement comprises a clearance flow seal above the pressure recovery area. 5. The globe control valve of claim 4, wherein the clearance flow seal comprises:an outer seal contacting the cage; andan inner seal between the plug and the outer seal. 6. The globe control valve of claim 5, wherein the outer seal comprises an overlapping joint. 7. The globe control valve of claim 5, wherein the inner seal is elastomeric. 8. A control valve comprising:a body defining a fluid flow path;a closure member positioned in the flow path to modify a rate of fluid flow through the valve;a flow orifice in the flow path comprising a seating surface interacting with the closure member to close the valve; anda pressure recovery area defined, at least in part, by the closure member when positioned above the seating surface, wherein at least a portion of the flow path includes a first wall, the closure member includes a second wall substantially parallel to the first wall, and wherein the pressure recovery area includes a gap between the first and second walls. 9. The control valve of claim 8, comprising a port region in the body, wherein the port region comprises one or more ports through which fluid flows and with which the closure member interacts to modify the rate of fluid flow through the valve. 10. The control valve of claim 9, comprising a cage aligning the closure member, wherein the cage comprises the one or more ports. 11. The control valve of claim 10, wherein the pressure recovery area is between the closure member and the cage. 12. The control valve of claim 10, wherein the cage and the closure member define a clearance and the control valve comprises a clearance flow seal reducing flow through the clearance. 13. The control valve of claim 8, wherein the control valve has a rangeability greater than 100:1. 14. The control valve of claim 8, wherein the control valve has a rangeability greater than 500:1. 15. The control valve of claim 12, wherein the clearance flow seal comprises:an outer seal contacting the cage; andan inner seal between the outer seal and the closure member. 16. The control valve of claim 12, wherein the pressure recovery area is between the closure member and the cage. 17. The control valve of claim 16, wherein the pressure recovery is between the clearance flow seal and the seating surface. 18. The control valve of claim 17, wherein the closure member is a plug. 19. The control valve of claim 18, wherein the plug is cylindrical. 20. A control valve comprising:a body defining a fluid flow path;a closure member positioned in the flow path to modify a rate of fluid flow;a cage aligning the closure member, wherein the cage and the closure member define a clearance through which fluid flows;a flow orifice in the flow path comprising a seating surface interacting with the closure member to close the valve; anda clearance flow seal between the closure member and the cage and above the seating surface, wherein the clearance flow seal comprises an outer seal contacting the cage and an inner seal between the outer seal and the closure member. 21. The control valve of claim 20, wherein the valve has a rangeability greater than 100:1. 22. The control valve of claim 20 , wherein the valve has a rangeability greater than 500:1. 23. The control valve of claim 20, wherein the inner seal is elastomeric. 24. A control valve comprising:a body defining a fluid flow path;a closure member positioned in the fluid flow path to modify a rate of fluid flow;a cage aligning the closure member and comprising one or more ports through at least one sidewall of the cage, through which fluid flows, wherein the cage and the closure member define a clearance through which fluid flows;a flow orifice in the flow path comprising a seating surface interacting with the closure member to close the valve;a clearance flow seal positioned above the seating surface and between the closure member and the cage to reduce flow through the clearance; anda pressure recovery area above the seating area, defined by a recess of the closure member with at least one wall substantially parallel to the at least one sidewall of the cage. 25. The control valve of claim 24, wherein the closure member is a plug adapted to move linearly. 26. The control valve of claim 24, wherein the pressure recovery area is below the clearance flow seal. 27. The control valve of claim 26, wherein the clearance flow seal comprises:an outer seal contacting the cage; andan inner seal between the closure member and the outer seal. 28. The control valve of claim 27, wherein the inner seal is elastomeric. 29. The control valve of claim 24, wherein the pressure recovery area is below the one or more ports when the closure member is seated on the seating surface. 30. The control valve of claim 29, wherein the closure member is a cylindrical plug adapted for linear movement in the cage, and the pressure recovery area is a gallery between the cage and the plug. 31. The control valve of claim 30, wherein the clearance flow seal comprises:an outer seal contacting the cage; andan inner seal between the outer seal and the plug, wherein the inner seal is elastomeric. 32. A control valve comprising:a linearly movable closure member positioned in a fluid flow path to modify a rate of fluid flow, wherein the closure member includes a recessed portion with at least one surface of the recessed portion substantially parallel to the linear path of the closure member;a cage aligning the closure member and comprising:one or more ports through which fluid flows, wherein the cage and the closure member define a clearance; andat least one surface defining the linear path of the closure member;a seating surface interacting with the closure member to close the valve; anda pressure recovery area between the cage and the closure member, wherein the pressure recovery area is below the one or more ports when the closure member is seated on the seating surface, and wherein the pressure recovery area is substantially defined by a space between the at least one surface of the closure member parallel to the linear path and the at least one surface of the cage defining the linear path of the closure member. 33. A control valve comprising:a linearly movable plug positioned in a fluid flow path to modify a rate of flow, wherein the plug includes a recessed portion with at least one wall substantially parallel to the direction of linear movement of the plug;a staged cage aligning the plug and comprising a plurality of ports located axially along wall of the cage to vary fluid flow through movement of the plug, wherein the plug and the cage define a radial clearance, and wherein at least one wall of the recess of the plug is substantially parallel to the cage wall;a seating surface interacting with the plug to close the valve when the plug is seated;a pressure recovery area between the plug and the cage, wherein the pressure recovery area is below the plurality of ports when the plug is seated, and wherein the pressure recovery area is substantially defined by a gap having a uniform volume, the gap between the recessed portion of the plug and the cage wall; anda clearance flow seal between the ca ge and the plug and above the seat. 34. The control valve of claim 33, wherein the clearance seal comprises an outer seal contacting the cage and an inner elastomeric seal between the plug and the outer seal, whereby the clearance seal reduces fluid flow through the radial clearance. 35. A control valve comprising:a closure member positioned in a fluid flow path to modify a rate of fluid flow;an orifice in the fluid flow path;means for aligning the closure member;a first clearance defined between the closure member and the means for aligning the closure member; andmeans for encouraging the collapse of vapor bubbles, said means positioned between the orifice and the closure member when the closure member is opened, such that said means is substantially normal to the fluid flow path. 36. The control valve of claim 35, comprising means for reducing fluid flow through the clearance. 37. The control valve of claim 35, wherein:the closure member is a plug adapted to move linearly in the means for aligning the closure member;the orifice comprises a seating ring comprising a seating surface interacting with the plug to close the valve; andthe plug defines, at least in part, the means for encouraging collapse of vapor bubbles. 38. The control valve of claim 37, comprising means for reducing fluid flow through the clearance. 39. The control valve of claim 38, wherein the means for reducing fluid flow through the clearance is positioned above the seating surface and moves linearly with the plug. 40. The control valve of claim 35, wherein the means for encouraging collapse of vapor bubbles is positioned above the seating surface when the closure member is closed. 41. A control valve comprising:an orifice in a fluid flow path, the orifice comprising a seating surface;a cage comprising one or more ports above the seating surface;a plug operatively positioned for linear movement in the cage to modify a rate of fluid flow, wherein the plug and the cage define a clearance;a seal coupled with the plug positioned in the clearance; anda vapor recovery area below the seal and between the plug and the cage, wherein the vapor recovery area is at least partially defined by a recess in the plug, and wherein the recess has at least one wall that is substantially parallel to the linear movement of the plug. 42. The control valve of claim 41, wherein the plug is cylindrical and the vapor recovery area is a gallery defined, at least in part, by the plug.