Patent ID: 12196340

DETAILED DESCRIPTION

The following discussion is directed to various exemplary embodiments. However, one skilled in the art will understand that the examples disclosed herein have broad application, and that the discussion of any embodiment is meant only to be exemplary of that embodiment, and not intended to suggest that the scope of the disclosure, including the claims, is limited to that embodiment.

Certain terms are used throughout the following description and claims to refer to particular features or components. As one skilled in the art will appreciate, different persons may refer to the same feature or component by different names. This document does not intend to distinguish between components or features that differ in name but not function. The drawing figures are not necessarily to scale. Certain features and components herein may be shown exaggerated in scale or in somewhat schematic form and some details of conventional elements may not be shown in interest of clarity and conciseness.

In the following discussion and in the claims, the terms “including” and “comprising” are used in an open-ended fashion, and thus should be interpreted to mean “including, but not limited to . . . ” Also, the term “couple” or “couples” is intended to mean either an indirect or direct connection. Thus, if a first device couples to a second device, that connection may be through a direct connection, or through an indirect connection via other devices, components, and connections. In addition, as used herein, the terms “axial” and “axially” generally mean along or parallel to a central axis (e.g., central axis of a body or a port), while the terms “radial” and “radially” generally mean perpendicular to the central axis. For instance, an axial distance refers to a distance measured along or parallel to the central axis, and a radial distance means a distance measured perpendicular to the central axis. Any reference to up or down in the description and the claims is made for purposes of clarity, with “up”, “upper”, “upwardly”, “uphole”, or “upstream” meaning toward the surface of the borehole and with “down”, “lower”, “downwardly”, “downhole”, or “downstream” meaning toward the terminal end of the borehole, regardless of the borehole orientation.

As described above, valve systems, which include linear valve systems, are utilized to selectably control the flow of fluid through a fluid conduit by actuating a valve member between an open position and a closed position. Some valve systems may be powered (e.g., electrically, hydraulically, pneumatically, etc.) rather than manually operated. Additionally, some valve systems include locks configured to lock a valve member of the valve system into either an open position or a closed position preventing an actuator of the valve system from actuating the valve until the lock is placed into an unlocked configuration. For example, valve systems may include a lock configured to prevent a valve member from inadvertently actuating from the closed position into the open position (e.g., due to creep or for some other reason) whereby an inadvertent leak of fluid could occur across the valve system.

Locks for valve systems are typically powered, such as by hydraulics, between locked and unlocked configurations. For example, conventional locks may have an open circuit configured to convey hydraulic pressure to the lock to thereby actuate the lock from the locked configuration to the unlocked configuration, and a separate closed circuit configured to convey hydraulic pressure to the lock to thereby actuate the lock from the unlocked configuration to the locked configuration. Thus, at least some conventional locks do not lock automatically when the valve member of the valve system is actuated into the closed position. The lack of automatic locking may complicate the design of the valve system by requiring the addition of another hydraulic circuit (the closed circuit of the lock) to actuate the lock from the unlocked configuration to the locked configuration. The addition of a closed circuit also increases the complexity of operating the valve as an addition action must be taken (pressurizing the closed circuit of the lock) to lock the valve member of the valve system into the closed position, increasing the potential for operator error when operating the valve system. Additionally, while conventional locks include an automatic locking feature in which a single hydraulic circuit may both actuate the valve member of the valve system from the open position to the closed position and actuate the lock of the valve system form the unlocked configuration to the locked configuration. However, conventional automatic locks typically rely on a ball valve which may become stuck during the service life of the valve system, thereby preventing the lock from actuating into the locked configuration entirely.

Accordingly, embodiments disclosed herein include valve systems comprising valve locks configured to automatically lock the valve system into a closed configuration without the need to activate an additional, locking hydraulic circuit of the valve system. Instead, an operator (and/or a control system of the valve system) of the valve system need only actuate the valve system from an open configuration into the closed configuration in order to lock the valve system into the closed configuration by the valve lock. Once locked, the valve system cannot be returned to the open configuration until a hydraulic opening circuit coupled to the valve lock has been pressurized to thereby unlock the valve lock and thereby permit the operator to actuate the valve system into the open position by applying pressure to a separate hydraulic opening circuit of the valve system. This may prevent the inadvertent reopening of the valve system while preventing or mitigating potential issues in closing the valve system and locking it into the closed configuration.

Moreover, embodiments of valve locks described herein may automatically actuate into a locked configuration in response to the closure of the valve system without the need of a ball valve or other device which may be prone to failure during the operational life of the valve lock. Instead, a biasing member in conjunction with an inclined engagement surface of a collet assembly of the valve lock may be utilized to automatically actuate the valve lock into the locked configuration to thereby secure the valve system in the locked configuration.

Referring toFIGS.1,2, an embodiment of a valve system10is shown. In this exemplary embodiment, valve system10is generally configured to selectably isolate or seal a wellbore3extending through a subterranean earthen formation5from the ambient environment surrounding valve system10. Thus, valve system10may comprise a component of a well system, such as an offshore well system in which valve system10is positioned subsea near a sea floor7. In some embodiments, valve system10may comprise a BOP or other piece of well control equipment; however, in other embodiments the configuration of valve system10may vary. For instance, valve system10may comprise a gate valve or any other type of linearly actuated valve. Additionally, valve system10may be utilized in applications different from well systems in other embodiments.

In this exemplary embodiment, valve system10generally includes a valve housing12comprising a central passage14extending therethrough, a valve bonnet16extending laterally from the valve housing12, a valve member18positionable within the central passage14of the valve housing12, and a valve lock100configured to selectably lock the position of valve member18. When valve system10is in an open configuration, fluids and/or other materials may be conveyed between wellbore3and other equipment connected to valve system10via central passage14of valve housing12.

Valve member18of valve system10includes an open position (shown inFIG.1) corresponding to the open configuration of valve system10, and a closed position (shown inFIG.2) corresponding to the closed configuration of valve system10that is spaced along a central axis of the valve member18. Valve member18comprises a valve opening or passage20which is aligned and in fluid communication with the central passage14of valve housing12when valve member18is in the open position. Conversely, valve opening20or passage is offset from central passage14and valve member18seals central passage14when valve member18is in the closed position, thereby sealing or isolating a first portion15of central passage14from a second portion17of central passage14(valve member18being positioned between the first and second portions15,17). In this exemplary embodiment, valve member18comprises a valve gate; however, in other embodiments, the configuration of valve member18may vary. For example, in other embodiments, valve member18may comprise a ram (e.g., a blind ram, a shear ram, etc.) of a BOP.

In this exemplary embodiment, valve bonnet16comprises a valve passage22in which valve member18may be partially received when in the closed position. Additionally, in this exemplary embodiment, the valve member18is coupled to a piston24and comprises a tail rod26each of which are received in the valve passage22of valve member18and which travel in concert with valve member18. Particularly, piston24is sealably received within valve passage22whereby piston24divides valve passage22into a first or opening chamber25and a second or closing chamber27that is sealed from the opening chamber25by the piston24. Opening chamber25is in fluid communication with an opening hydraulic circuit30of valve system10while closing chamber27is in fluid communication with a second or closing hydraulic circuit31of valve system10. Each fluid circuit30,31may comprise a port connected to valve bonnet16, and one or more fluid conduits extending from the port. Additionally, each fluid circuit30,31is connected to a pressurized hydraulic source34which may selectably pressurize each hydraulic circuit30,31as controlled by a control system36of the valve system10.

For example, control system36may actuate valve system10from the open configuration shown inFIG.1to the closed configuration shown inFIG.2by applying hydraulic pressure from hydraulic source34to the closing chamber27while venting the opening chamber25. In this manner, a hydraulic closing force is applied to piston24, thereby displacing valve member18(connected to piston24) from the open position to the closed position. Conversely, control system36may actuate valve system10(e.g., in response to a command provided by an operator of valve system10, for example) from the closed configuration to the open configuration by applying hydraulic pressure from hydraulic source34to the opening chamber25while venting the closing chamber27. In this manner, a hydraulic opening force is applied to piston24, thereby displacing valve member18(connected to piston24) from the closed position to the open position. In other embodiments, the actuation of valve member18between the open and closed positions may be accomplished by means other than hydraulic force, such as via a biasing member, a pneumatic piston or actuator, and/or an electrically powered actuator.

Valve lock100of valve system10is configured to lock valve member18into the closed position such that valve member18may not inadvertently escape from the closed position and open the valve system10. For example, valve lock100may maintain valve member18in the closed position even should pressure within closing chamber27be lost due to a leak in the closing circuit31or some other malfunction of valve system10. Additionally, as will be described further herein, valve lock100is configured to lock the valve member18into the closed position automatically without the need of an additional hydraulic circuit101configured to actuate the valve lock100into a locked configuration. Instead, in this exemplary embodiment, valve lock100includes only an unlocking hydraulic circuit101similarly comprising one or more fluid conduits connected to hydraulic source34whereby hydraulic pressure may be selectably applied to valve lock100as controlled by the control system36. For example, control system36may apply hydraulic pressure from hydraulic source34to the valve lock100to actuate the valve lock100from the locked configuration to the unlocked configuration. Once in the unlocked configuration, control system36may apply hydraulic pressure to the opening chamber25of valve system10to displace the valve member18from the closed position to the open position.

Referring toFIGS.3-5, an embodiment of the valve lock100of valve system10ofFIGS.1,2, is shown inFIGS.3-5. As will be described further herein, valve lock100is configured to lock the valve system10into the closed configuration. Although valve lock100is shown inFIGS.1,2as a component of valve system10, in other embodiments, valve lock100may comprise a component of valve systems which vary in configuration from the valve system10shown inFIGS.1,2. In this exemplary embodiment, valve lock100has a central or longitudinal axis105and generally includes a case or housing assembly102, a collet assembly150, and a piston assembly180. For reference, a portion of the tail rod26of valve system10is shown inFIGS.3-5in order to illustrate how tail rod26interacts with the components of valve lock100. In this exemplary embodiment, central axis105of valve lock100is coaxial with a central or longitudinal axis of the tail rod26of valve member18. Thus, central axis105may also be referred to herein as the central axis105of valve member18.

Housing assembly102generally includes a hub104, an intermediate housing110, and an outer housing130. Hub102is configured to couple against the valve housing14of valve system10(e.g., via one or more fasteners) and includes a central passage106. Tail rod26is receivable within the central passage106of hub102. Additionally, hub102includes one or more annular bushings108located within the central passage106thereof. Bushings108centralize tail rod26within housing assembly102whereby tail rod26extends along and is centered about the central axis105of valve lock100.

The intermediate housing110of housing assembly102is positioned between hub204and outer housing130and includes a central opening112defined by a generally cylindrical inner surface114. Piston assembly180is received within the intermediate housing110. The inner surface114of intermediate housing comprises a pair of annular shoulders116,118spaced therealong. Additionally, an annular seal assembly120(e.g., one or more O-rings or other type of annular seal) is positioned on the inner surface114. Intermediate housing110additionally includes a radial port122extending entirely through the intermediate housing110and in fluid communication with the central opening112thereof. Radial port122may comprise a component of the unlocking hydraulic circuit101described above.

The outer housing130of housing assembly102includes a central opening112in which the collet assembly150is received. In this exemplary embodiment, outer housing130includes a central passage133, and an inner surface comprising an annular shoulder134located proximal an outer end of outer housing130. Additionally, outer housing130includes a plurality of circumferentially spaced radial apertures136each extending entirely through the outer housing130.

In this exemplary embodiment, the hub102and housings110,130of housing assembly104are coupled together by releasable clamps142coupled about the outer surfaces of hub102and housings110,130. In other embodiments, the hub102and housings110,130of housing assembly104may be coupled together in a different matter (e.g., via one or more threaded fasteners, etc.). In other embodiments hub102and housings110,130may be permanently coupled together via welding, for example. In still other embodiments, hub102, and housings110,130may be formed monolithically or integrally together as a singular housing. Thus, housing assembly102may also be referred to herein as housing102.

Referring now toFIGS.3-7, additional views of the collet assembly150of valve lock100are shown inFIGS.6,7. Collet assembly150is configured to radially expand and contract relative to central axis105of valve lock100to actuate valve lock100between locked and unlocked configurations. Thus, collet assembly150may also be referred to herein as locking assembly150. In this exemplary embodiment, collet assembly150comprises a central passage151, and a plurality of circumferentially spaced locking members or wedges152and a plurality of corresponding circumferentially spaced retention assemblies170. Collet assembly150comprises a central or longitudinal axis that is coaxial with central axis105of valve lock100. In this configuration, collet assembly150extends circumferentially about central axis105with axis105extending centrally therethrough. Given that collet assembly150extends coaxially with central axis105, central axis105may also be referred to herein as the central axis105of collet assembly150.

As shown particularly inFIG.7, each wedge152of collet assembly150comprises a longitudinal first end154, a longitudinal second end156opposite first end154, an arcuate outer surface158extending between ends154,156, and an arcuate inner surface160also extending between ends154,156. In this exemplary embodiment, the inner surface160of each wedge152comprises an inclined surface162extending from the first end154thereof. Inclined surface162extends at a non-zero, non-orthogonal angle (e.g., any angle greater than zero degrees and less than ninety degrees) relative to the central axis105of valve lock100. The second end156of each wedge152defines an orthogonal surface or shoulder164which extends substantially orthogonal relative to the central axis105of valve lock100.

As will be discussed further herein, retention assemblies170are configured to urge valve lock100into the locked configuration. As shown particularly inFIG.5, in this exemplary embodiment, each retention assembly170generally includes an elongate member or retention pin172, a biasing member174, and an annular pin holder176. The retention pin172of each retention assembly170extends through a central aperture of the pin holder176and is coupled to the outer surface158of a corresponding wedge152. For example, the retention pin172may be threaded into a threaded aperture formed in the outer surface157of the wedge152, however the mechanism by which the retention pin172is coupled to the corresponding wedge152may vary. The biasing member174of each retention assembly extends between the outer surface158of the corresponding wedge152and the pin holder176. In this configuration, biasing member174exerts a radially inwards directed (relative central axis105) force against the corresponding wedge152, urging the wedge152towards the central axis105of valve lock100. Additionally, the pin holder176is coupled to one of the apertures146formed in the outer housing130of housing assembly102, thereby delimiting the radial travel of the retention pin172and the corresponding wedge152coupled thereto. While biasing members174are shown as comprising coil springs, in other embodiments, the configuration of biasing members174may vary.

In this configuration, each wedge152is permitted to travel radially between a radially inner position (shown inFIGS.5,6) and a radially outer position having a greater radius relative to the central axis105relative to the radially inner position. The radially inner positions of wedges152correspond to a radially inner configuration of collet assembly150while the radially outer positions of wedges152correspond to a radially outer configuration of the collet assembly150. The radially inner positions of wedges152correspond to the locked configuration of valve lock100while the radially outer positions of wedges152correspond to the unlocked configuration of valve lock100. As will be described further herein, wedges152may be actuated from their radially inner positions shown inFIGS.5,6to their radially outer positions by piston assembly180.

As shown particularly inFIG.5, in this exemplary embodiment, piston assembly180has a central or longitudinal axis coaxial with central axis105of valve lock and generally includes an annular piston182, a plurality of circumferentially spaced biasing assemblies200, and an annular retention sleeve or mandrel220. Given that piston assembly180extends coaxially with central axis105, central axis105may also be referred to herein as the central axis105of piston assembly180.

Piston182of piston assembly180generally includes a longitudinal first end183, a longitudinal second end184opposite first end183, a cylindrical outer surface186extending between ends183,184, and a central passage185extending between ends183,184and which receives a terminal end28of the tail rod26. In this exemplary embodiment, an annular seal assembly188(e.g., one or more O-rings or other type of annular seal) is positioned on the outer surface186of piston182and sealingly engages the inner surface114of the intermediate housing110of housing assembly102. Additionally, outer surface186comprises an annular shoulder located axially between the first end183and the seal assembly188of piston182. Seal assembly188defines a sealed piston chamber191within which hydraulic pressure may be applied against the shoulder of piston182to exert an axially directed, hydraulic pressure force against piston182in the direction of collet assembly150. Piston chamber191may be in fluid communication with radial port122to thereby fluidically connect the piston chamber191with the unlocking hydraulic circuit101shown inFIGS.1,2whereby control system36may selectably apply hydraulic pressure to the piston chamber191from pressurized hydraulic source34.

In this exemplary embodiment, piston182includes a piston extension192defining the second end184of piston182and extending axially towards the collet assembly150. Piston extension192includes an annular, inclined engagement surface194which physically engages or contacts the plurality of wedges152of collet assembly150. As will be described further herein, the inclined engagement surface194of piston extension192is configured to selectably displace the plurality of wedges152into their unlocked positions. Additionally, piston extension192includes a plurality of circumferentially spaced radial ports196extending therethrough.

Piston182may travel between a first or disengaged position (shown inFIG.5) and a second or engaged position that is axially spaced from the disengaged position and which is configured to actuate the wedges152of collet assembly150into their unlocked positions. Piston182may be actuated from the disengaged position to the engaged position by applying hydraulic pressure to piston chamber191. Fluid on the opposing side of shoulder190may be vented to the central passage185of piston182via radial ports196. Conversely, biasing assemblies200are configured to urge the piston182towards the disengaged position and thus piston182may only be actuated from the disengaged position to the engaged position when the hydraulic pressure force applied to piston182exceeds the biasing force applied to piston182by biasing assemblies200.

In this exemplary embodiment, each biasing assembly200comprises a support rod202and a biasing member204extending about the support rod202and between the piston182and the retention sleeve220. The retention sleeve220is positioned about piston extension192of piston182and is secured between the intermediate housing110and outer housing130of housing assembly102whereby relative axial movement between retention sleeve220and housing assembly102is restricted. In this exemplary embodiment, retention sleeve220is captured between opposing shoulders of intermediate housing110and outer housing130; however, in other embodiments, the manner of securing retention sleeve220to housing assembly102may vary. In still other embodiments, retention sleeve220may be formed integrally with housing assembly102. In this exemplary embodiment, biasing members204contact both the retention sleeve220and piston182thereby imparting an axially directed biasing force to the piston182towards the disengaged position. While biasing members204are shown as comprising coil springs204inFIG.5, in other embodiments, the configuration of biasing members204may vary.

Referring now toFIGS.8-11, having described the structure of the embodiment of valve lock100shown inFIGS.3-7, an exemplary method of operating the valve lock100will now be described. Particularly,FIG.8illustrates tail rod26in a first position corresponding to the open configuration of valve system10shown inFIGS.1,2. In this position, an annular retainer30(e.g., a retainer nut or other radially enlarged member) coupled to the terminal end28of tail rod26is positioned adjacent the inclined surfaces162of the wedges152of collet assembly150.

In this exemplary embodiment, when valve system10is actuated into the closed configuration the tail rod26is displaced axially in a first direction (indicated by arrow135inFIGS.8-11) of the outer housing130of housing assembly102. As tail rod26travels in the first direction135, retainer30physically engages the inclined surface162of each wedge152. Due to the acute angle formed between inclined surfaces162and central axis105, the axial force applied to tail rod26to displace it along first direction135is transferred to wedges152as a radially outwards force causing wedges152to travel from a radially inwards position (shown inFIG.8) to a radially outwards position (shown inFIG.9) in a direction orthogonal central axis105. While retention assemblies170urge wedges152towards their radially inner positions, the force from tail rod26exceeds the biasing forces applied to wedges152, causing them to enter their radially outer positions shown inFIG.9. Although in this exemplary embodiment the wedges152are biased towards their radially inner positions by retention assemblies170, in other embodiments, a different mechanism may urge wedges152towards their radially inner positions. For example, a hydraulic locking circuit may be employed to actuate wedges152into their radially inner positions in response to pressurizing the locking circuit and applying a radially inwards directed pressure force against the wedges152of collet assembly150.

With wedges152in their radially outer positions, collet assembly150is disposed in an unlocked configuration which permits the retainer30of tail rod26to travel through the central passage151of collet assembly150such that retainer30occupies the central passage133of outer housing130as shown particularly inFIG.10. With retainer30positioned in central passage133of outer housing130and external the central passage151of collet assembly150, wedges152are forced again into their radially inner positions by the biasing forces applied by retention assemblies170, as shown particularly inFIG.10. In this manner, valve lock100is actuated from the unlocked configuration shown inFIG.9to the locked configuration shown inFIG.10automatically by retention assemblies170without the need to apply hydraulic pressure to an additional hydraulic circuit. Particularly, with wedges152returned to their radially inner positions, tail rod26is prevented from travelling in a second axial direction (indicated by arrow137inFIGS.8-11) opposite first direction135due to contact between an annular shoulder32of retainer30and the second end156of each wedge152. In other embodiments, the direction of travel of tail rod26corresponding to actuating valve system10from the open position to the closed position may be reversed from that shown inFIGS.8-11.

To reopen valve system10, valve lock100may be actuated from the locked configuration shown inFIG.10to the unlocked configuration shown inFIG.11. In this exemplary embodiment, valve lock100is actuated from the locked configuration to the unlocked configuration by applying hydraulic pressure from hydraulic source34to the piston chamber191of valve lock100via unlocking hydraulic circuit101. Particularly, pressurizing piston chamber191exerts a hydraulic pressure force against piston182in the first direction135exceeding the biasing forces applied by biasing assemblies200, thereby displacing piston182in the first direction135. As piston182travels in the first direction135, the inclined engagement surface194of piston extension192engages the inclined surface162of each wedge152of collet assembly150, thereby forcing each wedge152back into its radially outer position. With each wedge152in the radially outer position, tail rod26is free to return to the first position corresponding to the open configuration of valve system10in response to the pressurizing of opening hydraulic circuit30of valve system10. In this manner, valve lock100may be selectably unlocked by an operator of valve system10(preventing an inadvertent unlocking of valve lock100) first before the valve system10is permitted to actuate into the open configuration.

While exemplary embodiments have been shown and described, modifications thereof can be made by one skilled in the art without departing from the scope or teachings herein. The embodiments described herein are exemplary only and are not limiting. Many variations and modifications of the systems, apparatus, and processes described herein are possible and are within the scope of the invention. For example, the relative dimensions of various parts, the materials from which the various parts are made, and other parameters can be varied. Accordingly, the scope of protection is not limited to the embodiments described herein, but is only limited by the claims that follow, the scope of which shall include all equivalents of the subject matter of the claims. Unless expressly stated otherwise, the steps in a method claim may be performed in any order. The recitation of identifiers such as (a), (b), (c) or (1), (2), (3) before steps in a method claim are not intended to and do not specify a particular order to the steps, but rather are used to simplify subsequent reference to such steps.