WO2007075917A2

WO2007075917A2 - Pressure balancing valve

Info

Publication number: WO2007075917A2
Application number: PCT/US2006/048843
Authority: WO
Inventors: Varadharahen Lakshmanan; Laren J. Winkel; Michael P. Nelson
Original assignee: Flowserve Management Company
Priority date: 2005-12-22
Filing date: 2006-12-22
Publication date: 2007-07-05
Also published as: CA2794401C; CN101341358A; DE112006003392B4; DE112006003392T5; CA2631536C; CA2631536A1; WO2007075917A3; CN101341358B; CA2794401A1

Abstract

A three-way valve may be pressure balanced to improve efficiency of the three-way valve and to reduce operating forces and requirements for moving and/or manipulating plug assemblies within a three-way valve.

Description

PRESSURE BALANCING VALVE

PRIORITY CLAIM

This application claims the benefit of the filing date of United States Provisional Patent Application Serial No. 60/753,813, filed December 22, 2005, for "PRESSURE BALANCING VALVE."

TECHNICAL FIELD

The present invention relates to valves and, more particularly, to three-way valve systems incorporating a pressure balance system.

BACKGROUND

Valves are used with many different applications. Industrial valves are commonly used in chemical processing operations, gas piping operations, gas refinery operations, fluid and gas transport operations, and the like. There is a need for different types and sizes of valves for industrial operations.

A particular type of valve, a three-way valve, may be used to merge converging flows of fluid, gas, or other flowable material or to diverge a single flow into multiple flow channels. However, the pressures and forces encountered in the use of such three-way valves can be extreme. This is especially true in those instances where the three-way valve is being used in high-pressure and/or high-temperature applications or in applications having very high flow rates. The valve components, and especially the plug assembly components, used with three-way valves require immense amounts of force to manipulate the components of the valves. Typically, the amount of force required exceeds the amount of force that can be provided by standard actuators, resulting in the need for bulky and ^ expensive hydraulic systems to manipulate the plug assemblies of such valves. In some cases, the amount of force required is so excessive that use of a three-way valve is not feasible for the applications, effectively limiting the available sizes of the three-way valves. Thus, three-way valves may only be available for particular operations.

It is, therefore, desirable to develop three-way valves that may be manipulated with smaller amounts of force. It is also desirable to develop valves, such as three-way valves, that may be scaled such that they may be used for different operations.

DISCLOSURE OF THE INVENTION Embodiments of the invention relate to valves and, in particular, to three-way valves. According to particular embodiments of the invention, a three-way valve body may be fabricated as a single piece body and in some embodiments, each of the ports in the three-way valve can be positioned on sidewalls of the single piece valve body. According to other embodiments, the valve body can include at least one opening providing a configuration such that a bonnet may penetrate the body. In still other embodiments, an opening in the valve body can be configured for attaching plug assembly manipulation components and a second opening can be configured for accommodating trim and plug assembly components that may be used to pressure balance a three-way valve assembly constructed from the valve body.

Embodiments of the invention also may include three-way valves that are at least partially pressure balanced and in some instances completely pressure balanced. The pressure balanced three-way valves may include various configurations. For example, configurations having three gallery areas may provide for operation with converging flow or diverging flow operations. Pressure balanced three-way valves according to embodiments of the invention may include a bonnet penetrating into a valve body and extending beyond the valve body to guide and accommodate trim and plug assemblies used to pressure balance the valve. Other trim and plug assembly configurations can facilitate the pressure balancing of valve assemblies.

In still additional embodiments, methods for pressure balancing a three-way valve are provided. Some methods include the formation of a valve with a bonnet penetrating the valve body and extending outside of the valve body to facilitate placement of trim and plug assemblies that may be used in a pressure balanced valve. Other methods involve providing valve bodies with openings capable of housing trim and plug assemblies that may be pressure balanced.

According to certain embodiments of the invention, the amount of force required to move or manipulate plug assemblies and/or trim assemblies within three-way valves and other valves may be reduced by pressure balancing the valve components. Actuators and manual movement devices may be incorporated to facilitate the movement of the plug assemblies and/or trim assemblies of valves.

DESCRIPTION OF THE DRAWINGS

While the specification concludes with claims particularly pointing out and distinctly claiming that which is regarded as the present invention, this invention can be more readily understood and appreciated by one of ordinary skill in the art from the following description of the invention when read in conjunction with the accompanying drawings in which:

FIG. 1 is an illustration of a valve assembly according to a particular embodiment of the invention;

FIG. 2 is an illustration of an alternate view of the valve assembly illustrated in FIG. 1; FIG. 3 is a partial cross-sectional illustration of the valve body according to a particular embodiment of the invention;

FIG. 4 is a cross-sectional illustration of a valve assembly in a valve body according to a particular embodiment of the invention;

FIG. 5 is a cross-sectional illustration of the valve assembly in a valve body illustrated in FIG. 4 wherein the plug head is alternately positioned;

FIG. 6 is an illustration of a plug assembly according to a particular embodiment of the invention; and

FIG. 7 is a cross-sectional illustration of a valve assembly according to a particular embodiment of the invention.

MODE(S) FOR CARRYING OUT THE INVENTION Valve assemblies according to embodiments of the present invention provide pressure balancing within the valve assembly to relieve forces required to manipulate plug assemblies within the valve assemblies. In addition, embodiments of the invention may include three-way valve assemblies employing partial or complete pressure balancing to facilitate operation of the valve assemblies. The use of pressure balancing according to embodiments of the invention may allow larger three-way valves to be produced, used, and operated, with smaller plug assembly manipulating devices such as actuators and handwheels. Embodiments of the invention also include single piece construction valve bodies.

Embodiments of the invention include valve bodies and, in particular, valve bodies used as three-way valves. According to some embodiments of the invention, a three-way valve body is formed as a one-piece valve body. Formation of a one-piece valve body may help to reduce the size and weight of the valve body in addition to removing the need for additional seals and joints that are required when multi-piece valve bodies are assembled.

According to some embodiments of the invention, a three-way valve body may include three ports positioned on the sides of the valve body. For example, as illustrated in FIGS. 1 and 2, a valve body 100 includes a first port (port A) 170, a second port (port B) 180, and a third port (port C) 190, each of which provide ports to the interior of the valve body 100 from a sidewall of the valve body 100. The valve body 100 may also include an opening 102 to accept a bonnet to which an actuator, handwheel, or other device for moving an internal plug assembly in the valve may be attached. A bonnet flange 114 and body bolting 118 attaching the bonnet flange 114 to the valve body 100 are illustrated in FIGS. 1 and 2. The bonnet flange 114 holds a bonnet (not shown) in the opening 102 in or on the valve body 100. An actuator 160 is illustrated in a position attached to the top of the bonnet and bonnet flange 114.

According to other embodiments of the invention, the valve body may include a lower opening 104 in the valve body 100 to accommodate the placement of pressure/balancing trim components and plug, assembly components within the valve body 100 or to accommodate bonnet penetration into the valve body 100. For instance, in FIGS. 1 and 2, the second opening 104 is located in the bottom of the valve body 100 directly opposite the opening 102 on the top of the valve body 100. As illustrated, a lower bonnet flange 115 and lower body bolting 119 hold a lower bonnet (not shown) within the lower opening 104. A bonnet cap 150 attached to the lower bonnet or to a bonnet integrally formed with the bonnet cap may protect plug assembly components extending through the lower opening 104 or through a lower bonnet positioned within the lower opening 104.

A cross-sectional view of a valve body 100 according to particular embodiments of the invention is illustrated in FIG. 3. The interior of the valve body 100 includes three gallery areas, an upper gallery 192, a center gallery 172, and a lower gallery 182. The upper gallery 192 is formed by port C 190 in the valve body 100. The center gallery 172 is formed by port A 170 in the valve body 100. The lower gallery 182 is formed by port B (not shown because of cross-sectional cut away) in the valve body 100. Port A 170, and the center gallery 172, are in communication with the upper gallery 192 and the lower gallery 182 such that fluid, gas, or other flowable material may pass between the gallery areas. When the valve body 100 is assembled with trim and plug assembly components, flow of a fluid, gas, or other flowable material between the gallery areas may be controlled. An opening 102 in the upper portion of the valve body 100 may be configured to accept a bonnet and a device to manipulate a plug assembly housed within the valve body 100 or other trim and plug assembly components. A bonnet inserted in opening 102 may penetrate into the valve body 100. The lower opening 104 in the valve body 100 may also be configured to accept trim and plug assembly components. The lower opening 104 in the valve body 100 may allow room for trim and plug assembly components assembled in the valve body 100 to extend outside of the valve body 100. For example, the lower opening 104 may allow a pressure/balance plug assembly assembled in the valve body 100 to extend beyond the exterior of the valve body 100. The positioning of the opening 102 and the lower opening 104 also allow trim and plug assembly components to be positioned within the valve body 100 through both the opening 102 and the lower opening 104 of the valve body 100. This may help facilitate the assembly and/or the maintenance of a valve assembly.

Valve bodies 100 according to embodiments of the invention may be formed using casting and machining techniques, as known in the art. The valve bodies 100 may also be formed with different sizes and may be scaled up or down depending upon the desired operation for a valve constructed with the valve body 100. For example, a valve body 100 according to embodiments of the invention may be formed to assemble a 30.48 cm (12 inch), class 1500 valve. The valve bodies 100 may be formed to accommodate any other sizes and classes of valves as desired.

According to other embodiments of the invention, a lower opening 104 in a valve body may be incorporated with other valve body assemblies, such as a two-way valve body assembly or a multi-piece three-way valve body assembly, to accommodate placement of trim and plug assembly components within the valve body, and optionally extending outside of the valve body.

Although particular features of the valve bodies according to embodiments of the invention have been described with respect to one-piece valve bodies, it is understood that features of the invention may be incorporated with and used with valve bodies formed from two or more pieces, such as a two-piece valve body.

Other embodiments of the invention include three-way valve assemblies. The three-way valve assemblies of the invention may be partially or fully pressure balanced and scaleable to accommodate differing sizes of valve assemblies. A valve assembly according to particular embodiments of the present invention is illustrated in FIGS. 4 and 5. The valve assembly is enclosed within or positioned within a valve body 400, which may include a valve body 400, for example, such as those illustrated in FIGS. 1 and 2. The illustrated three-way valve body 400 includes a top portion, a bottom portion, port A, port B, and port C (not shown). The internal cavities formed by ports A, B, and C define a center gallery area, a lower gallery area, and an upper gallery area, respectively. An opening through the top portion of the valve body 400 communicates with the upper gallery area and port C. An opening between the upper gallery area and the center gallery area may allow communication of a liquid, gas, or other flowable material between the upper gallery area and the center gallery area. Likewise, an opening between the center gallery area and the lower gallery area may allow the communication of a liquid, gas, or other flowable material between the center gallery area and the lower gallery area. An opening in the bottom portion of the valve body 400 communicates with the lower gallery area and port B. In FIG. 4, the plug head 450 is positioned such that the center gallery and the upper gallery are in communication and communication to the lower gallery is blocked. In FIG. 5, the plug head 450 is positioned such that the center gallery and the lower gallery are in communication and communication to the upper gallery is blocked. The plug head 450 may also be positioned such that there is communication between each of the gallery areas. Valve assemblies according to embodiments of the invention may include various trim components and plug assembly components positioned within the valve body 400. The upper trim components of the valve assembly may include an upper bonnet 510 fitted in an opening at an end of a valve body 400 and attached thereto by an upper bonnet flange 514 and upper body bolting 518. The upper bonnet 510 may be connected to an upper pressure balance sleeve 530, which is fitted into the valve body 400. An upper pressure balance sleeve gasket 534 may be positioned between the upper pressure balance sleeve 530 and the valve body 400. The connection between the upper bonnet 510 and the upper pressure balance sleeve 530 may include an upper bonnet gasket 532. According to other embodiments of the invention, the upper bonnet 510 and upper pressure balance sleeve 530 may be a unitary structure. For instance, the upper bonnet 510 may include a portion that acts as, and performs the functions of, the upper pressure balance sleeve 530. The upper pressure balance sleeve 530, or the upper bonnet 510 in a unitary structure, may be connected to an upper seat retainer 540. The upper seat retainer 540 may be positioned in the upper gallery of the valve body 400 formed by the cavity of port C in the valve body 400. The upper seat retainer 540 may include upper seat retainer windows 545 allowing communication between an interior portion of the upper seat retainer 540, and an exterior portion of the upper seat retainer 540, which, is positioned in the upper gallery. Gas, fluid, or other flowable material flowing through port C of the valve body 400 may flow through the upper seat retainer windows 545 and into or out of a central portion of the upper seat retainer 540 and a central portion of the upper pressure balance sleeve 530. An upper seat ring 420 may be connected to or may be an integral part of a hanging cage 425 positioned in the center gallery of the valve body 400 formed by the cavity of port A and between the upper trim components and the lower trim components. The upper seat ring 420 and/or hanging cage 425 may be connected to the upper seat retainer 540 and may include a seat ring gasket 428 between the upper seat ring 420 and/or hanging cage 425 and the valve body 400.

The lower trim components include a lower seat ring 660 that may be connected to the hanging cage 425 and positioned within the valve body 400 with a lower seat ring gasket 662. A lower seat retainer 640 may be connected to the lower seat ring 660. The lower seat retainer 640 may include lower seat retainer windows 645, allowing communication between an interior portion of the lower seat retainer 640 and an exterior portion of the lower seat retainer 640 which is positioned in the lower gallery of the valve body 400. The lower seat retainer windows 645 allow the flow of a liquid, gas, or other flowable material into and out of an interior cavity of the lower seat retainer 640. The lower seat retainer 640 may be attached to a lower bonnet 610 positioned in an opening in the valve body 400. The lower bonnet 610 may include a cavity in communication with an interior cavity of the lower seat retainer 640. The lower bonnet 610 may be held in position within the valve body 400 by a lower bonnet flange 614 and lower body bolting 618. A bonnet cap 650 may be attached to the lower bonnet 610 by a packing gland flange and bolting 655.

In other embodiments of the invention, the lower bonnet 610 may be configured to include a cap portion as a unitary piece of the lower bonnet 610 in place of the bonnet cap 650.

In still other embodiments, a lower pressure balance sleeve (not shown) may be connected to the lower seat retainer 640, similar to the connection between the upper seat retainer 540 and the upper pressure balance sleeve 530. An alternative lower bonnet (not shown) similar to the upper bonnet 510 may be connected to the lower pressure balance sleeve and be attached to the valve body 400 by a lower bonnet flange 614 and lower bonnet bolting 618. A bonnet cap 650 may be attached to the alternative lower bonnet with a packing gland flange and bolting 655. The alternative lower bonnet may also be configured to include a cap portion as a unitary portion of the alternative lower bonnet. In still other particular embodiments, the valve body may include an extension that functions in a similar manner as the bonnet cap 650.

Valve assemblies according to embodiments of the invention may also include a plug assembly positioned within the upper trim and lower trim portions of the valve assembly. A plug assembly according to some embodiments of the invention is illustrated in FIG. 6. A plug assembly may include a plug head 450

(closure member) connected to an upper plug stem assembly and a lower plug stem assembly. The plug head 450 may include pressure balance channels 452 (longitudinal channel) positioned through an interior of the plug head 450 and in communication (e.g., via latitudinal channels) with a central portion of the plug head 450 that may be exposed to a gallery area when positioned in a valve body 400.

According to some embodiments of the invention, the upper plug stem assembly may include an upper plug stem 570 connected to an upper pressure balanced piston 580, which is connected to an upper guide stem .590. The upper pressure balanced piston 580 may include one or more wear rings and/or seals 582. The upper plug stem 570 may be connected to the plug head 450 and may include an upper pressure balance channel 572 in communication with a pressure balance channel 452 of the plug head 450. The upper pressure balance channel 572 extends through the upper plug stem 570 and the upper pressure balanced piston 580, and into the upper guide stem 590, where the upper pressure balance channel 572 meets one or more upper pressure balance openings 592. The upper pressure balance openings 592 provide communication between the upper pressure balance channel 572 and the exterior of the upper guide stem 590. As illustrated in FIG. 6, the upper plug stem 570, the upper pressure balanced piston 580, and the upper guide stem 590 may be a unitary assembly. According to such embodiments, the unitary upper plug stem may be connected to the plug head 450 and may include an upper pressure balance channel 572 through at least a portion of the unitary upper plug stem. The upper pressure balance channel 572 may connect to upper pressure balance openings 592 or may itself communicate with an exterior portion of the unitary upper plug stem.

The lower plug stem assembly according to some embodiments of the invention may include a lower plug stem 670 connected to a lower pressure balanced piston 680, which is connected to a lower guide stem 690. The lower pressure balanced piston 680 may include one or more wear rings and/or seals 682. The lower plug stem 670 may be connected to the plug head 450 and may include a lower pressure balance channel 672 in communication with a pressure balance channel 452 of the plug head 450. The lower pressure balance channel 672 may extend through the lower plug stem 670 and the lower pressure balanced piston 680, and into the lower guide stem 690, where the lower pressure balance channel 672 meets one or more lower pressure balance openings 692. The lower pressure balance openings 692 provide communication between the lower pressure balance channel 672 and the exterior of the lower guide stem 690.

In other embodiments, the lower plug stem assembly may include a unitary lower plug stem incorporating each of the lower plug stem 670, the lower pressure balanced piston 680, and the lower guide stem 690. The unitary lower plug stem may be connected to the plug head 450 and may include a lower pressure balance channel 672 through at least a portion of the unitary lower plug stem. The lower pressure balance channel 672 may connect to lower pressure balance openings 692 or may itself communicate with an exterior portion of the unitary lower plug stem.

The plug assembly illustrated in FIG. 6 may be positioned in the valve assembly as illustrated in FIGS. 4 and 5. The upper guide stem 590 is positioned within and through the upper bonnet 510 where it may be connected to a device capable of moving the plug assembly within the valve assembly, such as an actuator or handwheel. Upper packing, stem guides, and spacers 520 positioned within the upper bonnet 510 may help to position the upper guide stem 590 within the upper bonnet 510. The upper pressure balanced piston 580 is positioned in an interior cavity of the upper pressure balance sleeve 530 and is movable therein. The upper pressure balance openings 592 are positioned above the upper pressure balanced piston 580 and may freely communicate with a portion of the interior cavity of the upper pressure balance sleeve 530. The upper plug stem 570 extends from the upper pressure balanced piston 580 through an interior cavity of the upper seat retainer 540 and attaches to the plug head 450. The plug head 450 is moveable within the hanging cage 425 and may form a seal with the lower seat ring 660, as illustrated in FIG. 4, or the upper seat ring 420, as illustrated in FIG. 5, depending upon the position of the plug assembly within the valve assembly.

The lower portion of the plug assembly includes the lower plug stem 670 attached to the plug head 450 and positioned within an interior cavity of the lower seat retainer 640 and a portion of the interior cavity of the lower bonnet 610. The lower pressure balanced piston 680 is attached to the lower plug stem 670 and is moveable within an interior cavity of the lower bonnet 610. Mobility of the lower pressure balanced piston 680 may be accomplished through movement of the plug assembly by a device configured to provide such movement, such as an actuator or a handwheel. Wear rings and/or seals 682 may facilitate movement of the lower pressure balanced piston 680 within the cavity of the lower bonnet 610 (i.e., within an inner cavity of the valve) and may provide isolation between those portions of the lower bonnet 610 cavity separated by the lower pressure balanced piston 680. The lower pressure balance openings 692 are located on the side of the lower pressure balanced piston 680 closest to the lower guide stem 690 and may freely communicate with a portion of the interior cavity of the lower bonnet 610. The lower guide stem 690 is positioned within and through a passageway of the lower bonnet 610. Lower packing, stem guides, and spacers 620 positioned within the lower bonnet 610 may help to position the lower guide stem 690 within the lower bonnet 610. As the plug assembly is moved within the valve assembly, the lower guide stem 690 may extend outside of the lower bonnet 610 and into a cavity formed by the bonnet cap 650. The bonnet cap 650 may protect the lower guide stem 690 from external damage and may also protect operators using the valve assembly from impact by the lower guide stem 690 during operation of the valve assembly. Alternative plug assemblies incorporating alternative plug head 450 configurations having one or more pressure balance channels may be incorporated within a valve assembly according to other embodiments of the invention.

One or more devices for moving the plug assembly may also be included as part of the valve assembly. For example, as illustrated in FIGS. 4 and 5, an actuator 410 may be attached to the valve assembly and configured to maneuver the plug assembly within the valve assembly. Actuators 410 employed with valve assemblies according to embodiments of the invention may include electrically operated actuators, hydraulic actuators, pneumatic actuators, or other actuators as known in the art or as used with valve assemblies. In other embodiments, a handwheel or other device capable of being manually manipulated may be employed in combination with or in place of an actuator to impart movement to the plug assembly within the valve assembly.

According to other embodiments of the invention, the valve assembly may include one or more devices for moving the plug assembly within the valve assembly. For example, instead of an actuator 410 positioned at one end of the valve assembly and a bonnet cap 650 positioned at the other end of the valve assembly, the bonnet cap 650 could be replaced with a second actuator 410 or other device for moving the plug assembly. The lower trim components of the valve assembly illustrated in FTGS. 4 and 5 may be altered such that an actuator or handwheel could be attached in the position of the bonnet cap 650 to facilitate movement of the plug assembly within the valve assembly. The lower trim components could be constructed as illustrated in FIGS. 4 and 5, they could be constructed as a mirror image of the upper trim components, or different trim components and configurations could be adapted as needed to incorporate the use of a second device for moving the plug assembly within the valve assembly. The valve assemblies illustrated in FIGS.4 and 5 according to embodiments of the present invention may be pressure balanced. The plug head 450 pressure balance channels 452 are in communication with the upper pressure balance channel 572 and the lower pressure balance channel 672. The pressure in the center gallery area is communicated through the plug head 450 pressure balance channels 452 to the cavity in the upper pressure balance sleeve 530 and the lower bonnet 610 by way of the respective pressure balance channels in communication with the pressure balance channels 452. The communication of the pressure within the center gallery area to the cavity in the upper pressure balance sleeve 530 above the upper pressure balance piston 580 equalizes the pressure between those two areas. Likewise, communication of the pressure within the center gallery area to the cavity in the lower bonnet 610 cavity below the lower pressure balance piston 680 equalizes the pressure between those two areas. The equalization of the pressure in the upper pressure balance sleeve 530 cavity portion and lower bonnet 610 cavity portion with the central gallery area reduces the amount of force required by an actuator or handwheel to move or manipulate the plug assembly. In some embodiments, the pressure balance eliminates forces other than frictional forces encountered with plug assembly movement, thereby greatly reducing the amount of force required to move or manipulate the plug assembly. The use of pressure balancing with a three-way valve helps facilitate the fabrication of larger valves and the reduction in the amount of force required to move or manipulate the plug assembly. In many applications involving high pressure, high temperature, or high flow rates in three-way valves, the forces exerted by the flow rates and pressure drops significantly hindered movement of the plug assembly within a valve. The pressure balancing according to embodiments of the invention reduces the required forces.

Three-way valves according to embodiments of the invention are also improved by the presence of an opening in the valve body allowing a lower bonnet 810 to be positioned such that it penetrates the valve body. The open configuration of the valve body also assists in the configuration of the trim assembly and plug assemblies such that a pressure balanced system can be employed with a three-way valve assembly. The open configuration of the valve body may help to facilitate the trim and balancing of the valve assembly. A valve assembly according to still other embodiments of the invention is illustrated in FIG. 7. The valve assembly includes a valve body 700, trim components, and a plug assembly. The valve body 700 may include a valve body according to embodiments of the invention such as the valve bodies illustrated in FIGS. 1 and 2.

The trim components of the valve assembly illustrated in FIG. 7 include an upper bonnet 710 seated on the valve body 700 and attached thereto by an upper bonnet flange 714 and upper body bolting 718. An actuator assembly 705 or manual device may be mounted to the upper bonnet 710 for manipulating a plug assembly of the valve. An upper pressure balance sleeve 730 may sit in the valve adjacent to the upper bonnet 710 and an upper bonnet gasket 732 may be positioned between the upper pressure balance sleeve 730 and the upper bonnet 710. An upper pressure balance sleeve gasket cavity 734 may be positioned between the upper pressure balance sleeve 730 and the valve body 700. An upper seat retainer 740 may be positioned next to the upper pressure balance sleeve 730 and includes upper seat retainer windows 745 which may allow the flow of a fluid, gas, or other flowable material into and out of a cavity on the interior of the upper seat retainer 740. The upper seat retainer 740 may be positioned over an upper seat ring 722, which may or may not be an integral part of a hanging cage 725 positioned below the upper seat ring 722 and within a center gallery area of the valve body 700. A lower seat ring 860 may be positioned next to the hanging cage 725 and a lower seat ring gasket 862 may be positioned between the lower seat ring 860 and the valve body 700. A lower seal retainer 840 having lower seat retainer windows 845 may be positioned between the lower seat ring 860 and a lower bonnet 810. The lower bonnet 810 can extend into the valve body 700 and out an opening in the valve body 700. The lower bonnet 810 may be attached to the valve body 700 by a lower bonnet flange 814 and lower body bolting 818. A lower bonnet gasket 819 maybe positioned between a portion of the lower bonnet 810 and the valve body 700.

A plug assembly similar to that illustrated in FIG. 6 may be incorporated with the valve assembly. For example, the plug assembly illustrated in FIG. 7 may include an upper guide stem 790 positioned within a portion of the upper bonnet 710 and upper pressure balance sleeve 730. An upper pressure balanced piston 780 positioned within an interior compartment of the upper pressure balance sleeve 730 may be formed as an integral part of the upper guide stem 790 or as a separate component attached to the upper guide stem 790. Likewise, an upper plug stem 770 extending from the upper pressure balanced piston 780 into an interior compartment of the upper seat retainer 740 may be attached to an upper pressure balanced piston 780 or to an integral extension of the upper pressure balanced piston 780. Wear rings and/or seals 782 may be incorporated with the upper pressure balanced piston 780. The upper plug stem 770 may be connected to a plug head 750 positioned within the hanging cage 725 between the upper seat ring 722 and the lower seat ring 860. The plug head 750 may include one or more openings or pressure balance channels 752 through the plug head 750 to facilitate pressure balancing of the gallery area occupied by the plug head 750 with other gallery areas within the valve body 700. One or more of the pressure balance channels 752 may communicate with an upper pressure balance channel 772 located in the upper plug stem 770. One or more upper pressure balance openings 792 may communicate with an upper pressure balance channel 772 and an interior portion of the upper pressure balance sleeve 730 located between the upper bonnet 710 and the upper pressure balance piston 780, as illustrated in FIG. 7. Upper packing, stem guides, and spacers 720 may help guide or support the upper guide stem 790.

The lower portion of the plug assembly is attached to the plug head 750 and includes a lower plug stem 870 connected to the plug head 750 and extending through the lower seat retainer 840 and into the lower bonnet 810. A lower pressure balance piston 880 is connected to the lower plug stem 870, or can be formed as art integral part thereof and is located in a cavity formed within the lower bonnet 810 as illustrated. Wear rings and/or seals 882 may be incorporated with the lower pressure balance piston 880. A lower pressure balance channel 872 communicates with one or more of the pressure balance channels 752 and runs the length of the lower plug stem 870. A terminal end of the lower pressure balance channel 872 exits the lower plug stem 870 on a side of the lower pressure balance piston 880 opposite the side closest to the plug head 750 and into a portion of the lower bonnet 810 cavity. An actuator assembly 705 may include an electronic actuator, a pneumatic actuator, a hydraulic actuator, or other actuator device capable of manipulating a plug assembly within a valve. In alternate embodiments, the actuator assembly 705 may be substituted with a handwheel or other device for manually manipulating a plug assembly within a valve.

The valve assembly illustrated in FIG. 7 may be pressure balanced in a similar manner as with other embodiments of the invention. The pressure balance channels 752 in the plug head 750 may communicate or transfer the pressure in the central gallery area to an area of the upper pressure balance sleeve 730 cavity and to a portion of the lower bonnet 810 cavity through the upper pressure balance channel 772 and lower pressure balance channel 872. The trim in the valve assembly illustrated in FIG. 7 may be fully balanced, however, the lower plug stem 870 is exposed to the pressure from the pressure balancing.

According to embodiments of the invention, the plug assembly of the three-way valve assembly illustrated in FIG. 7 may be driven by an actuator normally used to drive a two-way pressure balanced valve. For example, a size 400 actuator may be used with the valve assembly illustrated in FIG. 7. Other actuator sizes may also be used according to embodiments of the invention.

Embodiments of the invention such as those illustrated in FIG. 7 may not achieve complete pressure balancing. However, such embodiments may achieve 70, 80, 90, 95 percent or more of a total desired pressure balance. Such embodiments may be less complex and easier to fabricate than other embodiments of the invention. Thus, these embodiments may be advantageous where total pressure balancing is not desired but where significant improvements in plug assembly movement are desired.

Although certain embodiments of the invention have been described with respect to particular trim and plug assembly components, it is understood that other trim and plug assembly components may be used with the various embodiments of the invention. For example, in some operations, it may be desirable to include severe service trim components within a valve according to embodiments of the invention. The use of severe service trim components has heretofore been unavailable for use with three-way valves. However, embodiments of the present invention may be equipped with severe service components. In such cases, severe trim components such as anti-cavitation retainers and/or anti-noise retainers could be fined on any or all of the ports of the valves of embodiments of the invention. Furthermore, additional trim components such as gaskets, seals, bushings, packing, guides, and other components may be added to or removed from the valve and plug assemblies according to embodiments of the invention.

Embodiments of the invention may also be designed and configured for fail-in-place action or for fail-safe action wherein fail-safe springs are incorporated into the trim assembly. Other trim and safety components may be incorporated with the various embodiments of the invention.

According to other embodiments of the invention, the diameters of the ports may vary as desired. In addition, the seat diameters, sleeve diameters, and stem diameters used with the trim assemblies may be equal or different throughout a valve assembly and they may be configured to provide force and/or bias corrections as needed in the valve assemblies.

The valve bodies, valve assemblies, and pressure balanced trim assemblies of the various embodiments of the invention may be used in many different scenarios. For example, valve assemblies according to embodiments of the invention may be used with high-pressure applications including, but not limited to, chemical production, gas production and refining, gas transport, fluid transport, fluid mixing, and other such applications.

Valve assemblies according to embodiments of the invention employ pressure balancing within the valve in order to reduce the amount of force required to move and/or manipulate the trim and plug assemblies in the valve assembly. The use of embodiments of the invention in valves therefore allows smaller actuators to be used than were previously required for similar applications. In addition, the valve assemblies according to embodiments of the invention allow for the use of three-way valves in valve operations where such valves were previously non-existent due to limitations on the valve sizes and the force requirements.

The valve assemblies according to embodiments of the invention may be used with diverging flow applications. For instance, a three-way valve according to embodiments of the invention may divert the flow of a fluid, gas, or other flowable material entering port A and the center gallery area to either or both of port B and port C. The plug assembly and position of the plug head within the valve assembly may dictate the amounts of flow diverted from port A to either port B, port C, or both ports B and C. Embodiments of the invention may also be used with converging flow applications. For example, a three-way valve according to embodiments of the invention may have a first stream entering port C and the upper gallery and a second stream entering port B and the lower gallery. Depending upon the placement of the plug head within the center gallery, the two streams converge, or mix, and exit through the central gallery area and port A.

According to other embodiments of the invention, a method for facilitating movement of a plug assembly in a three-way valve assembly includes providing an opening in the valve body to facilitate construction of valve assemblies according to embodiments of the invention, hi still other embodiments of the invention, methods for reducing the forces required to move or manipulate a plug assembly in a three-way valve include pressure balancing or partially pressure balancing the trim and plug assemblies used with the three-way valve.

Having thus described certain currently preferred embodiments of the present invention, it is understood that the invention defined by the appended claims is not to be limited by particular details set forth in the above description, as many apparent variations thereof are contemplated without departing from the spirit or scope thereof as hereinafter claimed.

Claims

CLAIMSWhat is claimed is:

1. A valve comprising: a valve body; three ports in the valve body; an opening in a top of the valve body; a second opening in a bottom of the valve body; and a pressure balanced plug assembly located, positioned, and orientated to control flow between the three ports.

2. The valve of claim 1 , wherein the pressure balanced plug assembly is configured for linear actuation.

3. The valve of claim 1 , further comprising a bonnet penetrating the valve body via the first opening.

4. The valve of claim 1 , further comprising a second bonnet penetrating the valve body via the second opening.

5. The valve of claim 1 , wherein the pressure balanced plug assembly includes an upper portion operably coupled to a plug head and a lower portion operably coupled to the plug head.

6. The valve of claim 5, wherein the pressure balanced plug assembly is configured to equalize pressure experienced by the upper portion, plug head, and lower portion.

7. The valve of claim 1 , wherein the pressure balanced plug assembly is configured to achieve 70, 80, 90, and 95 percent total pressure balancing.

8. . The valve of claim 1 , wherein the pressure balanced plug assembly is configured to allow pressure equalization during actuation of the plug assembly.

9. The valve of claim 1 , wherein one of the three ports is an inlet and the remaining two ports are outlets.

10. The valve of claim 1, wherein two of the three ports are inlets and the remaining port is an outlet.

11. A valve body comprising: a cylindrical single piece valve body; a first port and second port positioned inline with each other and distally located on opposing sides of the valve body; a third port proximally located on a side differing from that of the first port and the second port.

12. The valve body of claim 1, further comprising an opening located in a proximal end of the valve body.

13. The valve body of claim 1 , further comprising a second opening located in a distal end of the valve body.

14. A valve comprising: a closure member including a longitudinal channel; a first valve stem operably coupled to the closure member to effect movement of the closure member via movement of the first valve stem, the first valve stem including a first channel in communication with the longitudinal channel, the first valve stem including a first opening in communication with the first channel; a first piston operably coupled to the first valve stem, such that movement of the first valve stem effects movement of the first piston, the first piston located between the first opening and the closure member; a second valve stem operably coupled to the closure member to effect movement of the second valve stem via movement of the closure member, the second valve stem including a second channel in communication with the longitudinal channel, the second valve stem including a second opening in communication with the second channel; and a second piston operably coupled to the second valve stem, such that movement of the second valve stem effects movement of the second piston; the second piston located between the first opening and the closure member.

15. The valve of claim 14, wherein the closure member further includes a latitudinal channel in communication with the longitudinal channel.

16. The valve of claim 14, further comprising a valve body.

17. The valve of claim 16, further comprising a first bonnet operably coupled to the valve body, the first bonnet positioned, located, and configured to position the first valve stem.

18. The valve of claim 17, further comprising a first sleeve operably coupled to the first bonnet, an interior of the valve body, and the first piston, the first sleeve operable to allow movement of the first piston.

19. The valve of claim 18, wherein the first piston is configured to isolate a portion of an interior of the first sleeve from a remainder of the interior of the valve body.

20. The valve of claim 17, wherein the first piston is configured to isolate a portion of the first bonnet from a remainder of an interior of the valve body.

21. The valve of claim 17, further comprising a second bonnet operably coupled to the valve body, the second bonnet positioned, located, and configured to position the second valve stem.

22. The valve of claim 16, where in the second piston is configured to isolate a portion of an inner cavity of the valve body.

23. The valve of claim 14, further comprising a first plug stem operably coupling the first valve stem to the closure member, the first plug stem having an other channel in communication with the longitudinal channel and the first channel.

24. The valve of claim 14, wherein at least one of the first valve stem and the second valve stem is configured for attachment to a valve actuator.