Patent ID: 12221847

DETAILED DESCRIPTION

The example embodiments discussed herein are directed to systems, apparatus, methods, and devices for tubing hanger retention systems for wellhead assemblies. Example embodiments can be used in wellhead assemblies for subterranean field operations (e.g., injection operations, production operations). Example embodiments can be used for wellhead assemblies in both land-based and offshore subterranean operations. While example embodiments are described as being used in conjunction with tubing hangers herein, example embodiments can be used, in full or in part, in conjunction with other components (e.g., a casing hanger) of a wellhead assembly.

A wellhead assembly that includes example tubing hanger retention systems can include one or multiple components, where a component can be made from a single piece (as from a mold or an extrusion or a three-dimensional printing process). When a component (or portion thereof) of a wellhead assembly that includes example tubing hanger retention systems is made from a single piece, the single piece can be cut out, bent, stamped, and/or otherwise shaped to create certain features, elements, or other portions of the component. Alternatively, a component (or portion thereof) of a wellhead assembly that includes example tubing hanger retention systems can be made from multiple pieces that are mechanically coupled to each other. In such a case, the multiple pieces can be mechanically coupled to each other using one or more of a number of coupling methods, including but not limited to adhesives, welding, fastening devices, compression fittings, mating threads, and slotted fittings. One or more pieces that are mechanically coupled to each other can be coupled to each other in one or more of a number of ways, including but not limited to fixedly, hingedly, rotatably, removably, slidably, and threadably.

Wellhead assemblies that include example tubing hanger retention systems can be designed to comply with certain standards and/or requirements. Examples of entities that set such standards and/or requirements can include, but are not limited to, the Society of Petroleum Engineers, the American Petroleum Institute (API), the International Standards Organization (ISO), and the Occupational Safety and Health Administration (OSHA). Each component of a wellhead assembly (including portions thereof) can be made of one or more of a number of suitable materials, including but not limited to metal (e.g., stainless steel), ceramic, rubber, glass, fibrous material, and plastic.

If a component of a figure is described but not expressly shown or labeled in that figure, the label used for a corresponding component in another figure can be inferred to that component. Conversely, if a component in a figure is labeled but not described, the description for such component can be substantially the same as the description for the corresponding component in another figure. The numbering scheme for the various components in the figures herein is such that each component is a three-digit number and corresponding components in other figures have the identical last two digits. For any figure shown and described herein, one or more of the components may be omitted, added, repeated, and/or substituted. Accordingly, embodiments shown in a particular figure should not be considered limited to the specific arrangements of components shown in such figure.

Further, a statement that a particular embodiment (e.g., as shown in a figure herein) does not have a particular feature or component does not mean, unless expressly stated, that such embodiment is not capable of having such feature or component. For example, for purposes of present or future claims herein, a feature or component that is described as not being included in an example embodiment shown in one or more particular drawings is capable of being included in one or more claims that correspond to such one or more particular drawings herein.

Example embodiments of tubing hanger retention systems for wellhead assemblies will be described more fully hereinafter with reference to the accompanying drawings, in which example embodiments of tubing hanger retention systems for wellhead assemblies are shown. Tubing hanger retention systems for wellhead assemblies may, however, be embodied in many different forms and should not be construed as limited to the example embodiments set forth herein. Rather, these example embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of tubing hanger retention systems for wellhead assemblies to those of ordinary skill in the art. Like, but not necessarily the same, elements (also sometimes called components) in the various figures are denoted by like reference numerals for consistency.

Terms such as “first”, “second”, “outer”, “inner”, “top”, “bottom”, “above”, “below”, “distal”, “proximal”, “front,”, “rear,” “left,” “right,” “on”, and “within”, when present, are used merely to distinguish one component (or part of a component or state of a component) from another. This list of terms is not exclusive. Such terms are not meant to denote a preference or a particular orientation, and they are not meant to limit embodiments of tubing hanger retention systems for wellhead assemblies. In the following detailed description of the example embodiments, numerous specific details are set forth in order to provide a more thorough understanding of the invention. However, it will be apparent to one of ordinary skill in the art that the invention may be practiced without these specific details. In other instances, well-known features have not been described in detail to avoid unnecessarily complicating the description.

FIG.1shows a system100that includes a wellhead assembly129according to certain example embodiments. The system100includes multiple components. For example, as shown inFIG.1, the system100can include the wellhead assembly129, a Christmas tree116mounted atop the wellhead assembly129, a wellbore113in a subterranean formation127, one or more controllers104, one or more sensor devices185, and one or more users175, which can each include one or more user systems176. The wellhead assembly129of the system100can include an upper wellhead117, a tubing hanger120, a tubing spool150, a tubing hanger retention system135, and one or more of a number of remaining wellhead assembly components105. Examples of the remaining wellhead assembly components105can include, but are not limited to, a valve, a sensor device, piping, a casing spool, and a casing hanger. The wellbore113has a production casing106, inside of which is positioned a tubing string111. The tubing string111has a cavity133that extends continuously along its length, and there is an annulus123between the tubing string111and the production casing106that extends continuously along its length.

The components shown in the system100ofFIG.1are not exhaustive, and in some embodiments, one or more of the components shown inFIG.1may not be included in a wellhead assembly129in which an example tubing hanger retention system135can be used. Any component of the wellhead assembly129can be discrete or combined with one or more other components of the wellhead assembly129. Also, one or more components of the wellhead assembly129can have different configurations.

A user175can be any person that interacts, directly or indirectly, with a controller104, a sensor device185, the retention pin driver180, and/or any other component of the system100. Examples of a user175may include, but are not limited to, a company representative, an engineer, a geologist, a consultant, a contractor, and a manufacturer's representative. A user175can use one or more user systems176, which may include a display (e.g., a GUI). A user system176of a user175can interact with (e.g., send data to, obtain data from) a controller104, a sensor device185, and/or the retention pin driver180via an application interface and using the communication links105.

A user175can also interact directly with a controller104, a sensor device185, and/or the retention pin driver180through a user interface (e.g., keyboard, mouse, touchscreen). A user system176of a user175can interact with (e.g., sends data to, receives data from) a controller104, a sensor device185, and/or the retention pin driver180via an application interface. Examples of a user system176can include, but are not limited to, a cell phone with an app, a laptop computer, a handheld device, a smart watch, a desktop computer, and an electronic tablet.

The system100can include one or more controllers104. A controller104of the system100communicates with and in some cases controls one or more of the other components (e.g., a sensor device185, the retention pin driver180) of the system100. A controller104performs a number of functions that include obtaining and sending data, evaluating data, following protocols, running algorithms, and sending commands. A controller104can include one or more of a number of components. Such components of a controller104can include, but are not limited to, a control engine, a communication module, a timer, a counter, a power module, a storage repository, a hardware processor, memory, a transceiver, an application interface, and a security module. When there are multiple controllers104in the system100, each controller104can operate independently of each other. Alternatively, one or more of the controllers104can work cooperatively with each other. As yet another alternative, one of the controllers104can control some or all of one or more other controllers104in the system100. In some cases, a controller104is an optional component of the system100.

Each sensor device185includes one or more sensors that measure one or more parameters (e.g., pressure, distance, torque, flow rate, temperature, humidity, voltage, current). Examples of a sensor of a sensor device185can include, but are not limited to, a temperature sensor, torque sensor, a flow sensor, a pressure sensor, a gas spectrometer, a voltmeter, an ammeter, a permeability meter, a porosimeter, and a camera. A sensor device185can be integrated with and/or measure a parameter associated with one or more components (e.g., a retention pin130, the retention pin driver180, the tubing spool150) of the system100. For example, a sensor device185can be configured to measure a parameter (e.g., torque, distance) associated with moving a retention pin130within a tubing spool channel151. In some cases, the measurements made by one or more sensor devices185, each measuring a different parameter, can be used to determine and confirm whether a controller104should take a particular action (e.g., operate a valve, operate or adjust the retention pin driver180). In some cases, a sensor device185can include its own controller (e.g., controller104), or portions thereof. In some cases, a sensor device185is an optional component of the system100.

Each communication link105can include wired (e.g., Class1electrical cables, electrical connectors, Power Line Carrier, RS485) and/or wireless (e.g., sound or pressure waves in the water194, Wi-Fi, Zigbee, visible light communication, cellular networking, Bluetooth, Bluetooth Low Energy (BLE), ultrawide band (UWB), WirelessHART, ISA100) technology. A communication link105can transmit signals (e.g., communication signals, control signals, data) from one component (e.g., a controller104) of the system100to another (e.g., a valve on the Christmas tree116, the retention pin driver180).

Each power transfer link187can include one or more electrical conductors, which can be individual or part of one or more electrical cables. In some cases, as with inductive power, power can be transferred wirelessly using power transfer links187. A power transfer link187can transmit power from one component (e.g., a battery, a generator) of the system100to another (e.g., a motor of the retention pin driver180). Each power transfer link187can be sized (e.g., 12 gauge, 18 gauge, 4 gauge) in a manner suitable for the amount (e.g., 480V, 24V, 120V) and type (e.g., alternating current, direct current) of power transferred therethrough.

The tubing hanger120(also called by other names, including but not limited to the tubing mandrel and the tubing head) of the wellhead assembly129is configured to support the tubing string111. Generally, the tubing hanger120is positioned toward the top of the wellhead assembly129. The tubing hanger120can have any of a number of configurations (e.g., mating threads, recesses) and/or components (e.g., pins) to support the tubing string111while also incorporating a sealing system to ensure that the cavity133within the tubing string111and the annulus123between the tubing string111and the production casing106are hydraulically isolated from each other. Once the wellbore113is drilled, the production casing106is inserted into the wellbore113to stabilize the wellbore113and allow for the extraction of subterranean resources (e.g., natural gas, oil) from the subterranean formation127. The production casing106is often secured to the subterranean formation127using cement injected in an intermediate field operation.

The tubing spool150(also called by other names, including but not limited to the wellhead spool) of the wellhead assembly129is configured to support the tubing hanger120, and so indirectly support the tubing string111. The tubing spool150has an inner channel inside of which the tubing hanger120is positioned within the wellhead assembly129. The tubing spool150and the tubing hanger120can abut against and form a seal between each other.

The upper wellhead117is coupled to and is positioned above the tubing spool150. The tubing hanger120is positioned inside of the upper wellhead117and the tubing spool150. The tubing hanger120and/or the tubing spool150can be coupled, directly or indirectly, to one or more remaining wellhead assembly components105. Examples of such remaining wellhead assembly components105can include, but are not limited to, the tubing string111, piping, a valve, a casing spool, and a casing hanger. At least one component (e.g., a remaining wellhead assembly component105) of the wellhead assembly129can be positioned at the surface102. Below the surface102is the subterranean formation127. Within the subterranean formation127is one or more (in this case, one) wellbores113. In some cases, the surface102is under water (e.g., a seabed). In such cases, the wellhead assembly129can be located in the water.

The tubing hanger retention system135of the system100ofFIG.1can include one or more of a number of components. In this example, the tubing hanger retention system135includes multiple retention pins130(e.g., retention pin130-1, retention pin130-2), multiple retention pin receiving features165(e.g., retention pin receiving feature165-1, retention pin receiving feature165-2), a retention ring160, and a retention pin driver180. The retention ring160of the tubing hanger retention system135is positioned over part (e.g., a top portion) of the outer perimeter of the tubing hanger120. As discussed below with respect toFIGS.2A through4C, the retention ring160can include multiple retention ring channels (e.g., retention ring channels289), where each retention ring channel is configured to receive the distal end of a retention pin130and/or part of a retention pin receiving feature165. In this example, there are two retention ring channels289(retention ring channel289-1and retention ring channel289-2).

Each of the retention pins130of the tubing hanger retention system135is positioned, at least in part, within one of the channels151(e.g., channel151-1, channels151-2) that traverse the thickness of the tubing spool150. In this case, the channels151(also sometimes called tubing spool channels151herein) are located on the tubing spool150in such a way that the channels151are positioned adjacent to the retention pin receiving features165of the retention ring160when the tubing spool150, the retention ring160of the tubing hanger retention system135, and the tubing hanger120are assembled in the wellhead assembly129. Each channel151in the tubing spool150can have any of a number of cross-sectional shapes (e.g., a circle, a square, an oval, a rectangle). The cross-sectional shape, as well as other characteristics (e.g., the diameter), of each channel151is configured to complement the corresponding characteristics of the retention pin130that is placed inside of the channel151. The configuration of one channel151can be the same as, or different than, the configuration of one or more of the other channels151.

The retention pins130are configured to be positioned within the channels151in the tubing spool150. The retention pins130are also configured to be received by the retention pin receiving features165of the retention ring160. Up until a retention pin130is engaged by a corresponding retention pin receiving feature165of the retention ring160, the retention pin130can be movably (e.g., slidably, rotatably) disposed within the channel151. The distal end of each retention pin130has an engagement feature that is configured to be captured by a retention pin receiving feature165of the retention ring160. Specifically in this case, the engagement feature at the distal end of retention pin130-1is captured by the retention pin receiving feature165-1of the retention ring160, and the engagement feature at the distal end of retention pin130-2is captured by the retention pin receiving feature165-2of the retention ring160. Examples of how the retention pins130and the retention pin receiving features165of the retention ring160can be configured are discussed below with respect toFIGS.2A through4C.

In some cases, the retention pins130are pre-inserted into the channels151before the tubing spool150is added to the wellhead assembly129. In alternative embodiments, the retention pins130can be inserted into the channels151after the tubing spool150is added to the wellhead assembly129. In some cases, a retention pin130can be engaged by a retention pin receiving feature165of the retention ring160independently of when the other retention pins130are engaged by the other retention pin receiving features165of the retention ring160. Alternatively, two or more of the retention pins130can be engaged by a retention pin receiving feature165of the retention ring160substantially simultaneously.

The retention pin driver180of the tubing hanger retention system135is a separate component that is configured to move the retention pins130within the channels151of the tubing spool150. The retention pin driver180can move the retention pins130inward with respect to the channels151. The inward movement can transition the status of the retention pins130, coupled to the retention pin receiving features165of the retention ring160, from a captured state to an engaged state. In some cases, the retention pin driver180can move the retention pins130inward to abut against the retention ring160.

The retention pin driver180can have any of a number of configurations. Such configurations are designed to complement the configurations of the proximal end of the retention pins130. For example, the retention pin driver180can be or include an automated rotary machine (e.g., a power nut driver, a power screw driver) that is capable of producing a controlled and high amount of torque to a feature and/or outer surface of the proximal end of the retention pins130that complements the configuration of the portion of the retention pin driver180that engages the proximal end of the retention pins130.

As another example, as shown inFIGS.3A and4Abelow, the retention pin driver180can be or include a collar that is threadably coupled to the tubing spool150. In such a case, the retention pin driver180can include an engagement surface (e.g., a chamfered bottom portion) that is configured to engage the proximal end of one or more of the retention pins130that is configured (e.g., have a chamfered proximal end) to complement the engagement surface of the retention pin driver180. Under such a configuration, when the collar moves in a certain direction (e.g., downward), the collar contacts the proximal ends of the retention pins130and forces the retention pins130to move inward within the channels151of the tubing spool150.

FIGS.2A through2Eshow various views of part of a wellhead assembly229that includes a tubing hanger retention system235according to certain example embodiments. Specifically,FIG.2Ashows a front view of the part of the wellhead assembly229.FIG.2Bshows a detailed front view of part of the tubing hanger retention system235with the retention pin230-1in a captured state.FIG.2Cshows a further detailed front view of part of the tubing hanger retention system235ofFIG.2Bwith the retention pin230-1in the captured state.FIG.2Dshows a detailed front view of part of the tubing hanger retention system235with the retention pin230-2in an engaged state.FIG.2Eshows a further detailed front view of part of the tubing hanger retention system235ofFIG.2Dwith the retention pin230-2in the engaged state.

Referring toFIGS.1through2E, the wellhead assembly229ofFIGS.2A through2Eincludes a tubing spool250, a tubing hanger220, a tubing string211, an upper wellhead217, the tubing hanger retention system235, multiple (in this case, two) valves213(valve213-1and valve213-2), and piping288. From the view provided inFIGS.2A through2E, the tubing hanger retention system235includes a retention ring260and two retention pins230(retention pin230-1and retention pin230-2). The tubing spool250, the tubing hanger220, the tubing string211, the upper wellhead217, and the tubing hanger retention system235of the wellhead assembly229are substantially the same as the tubing spool150, the tubing hanger120, the tubing string111, the upper wellhead117, and the tubing hanger retention system135of the wellhead assembly129described above with respect toFIG.1, except as discussed below. The piping288can include multiple pipes, ducts, elbows, joints, sleeves, collars, and similar components that are coupled to each other (e.g., using coupling features such as mating threads) to establish a network for transporting one or more fluids (e.g., an injection gas, a production fluid) at different times. Each component of the piping288can have an appropriate size (e.g., inner diameter, outer diameter) and be made of an appropriate material (e.g., steel, PVC) to safely and efficiently handle the pressure, temperature, flow rate, acidity, and other characteristics of the fluids that can flow therethrough.

Each of the valves213(also sometimes referred to a flow control valves213herein) can be placed in-line with the piping288at various locations in the wellhead assembly229to control the flow of one or more fluids at a given point in time. A valve213can have one or more of any of a number of configurations, including but not limited to a guillotine valve, a ball valve, a gate valve, a butterfly valve, a pinch valve, a needle valve, a plug valve, a diaphragm valve, and a globe valve. One valve213can be configured the same as or differently compared to another valve213in the wellhead assembly229. Also, one valve213can be controlled (e.g., manually, automatically by a controller) the same as or differently compared to another valve213in the wellhead assembly229.

Each valve213has a fully open position that allows a fluid to flow uninhibited therethrough and a fully closed position that prevents any fluid from flowing therethrough. In some cases, a valve213can also have any of a number of other positions (half open, a quarter closed, a quarter open) between fully open and fully closed that inhibit some amount of fluid flowing therethrough. Such other positions of a valve213can be discrete or continuous. One end of valve213-1is coupled to piping288that is directly coupled to the tubing spool250. The other end of valve213-1is coupled to additional piping288that leads to another component of the wellhead assembly229and/or larger system. Similarly, one end of valve213-2is coupled to piping288that is directly coupled to the tubing spool250. The other end of valve213-2is coupled to additional piping288that leads to another component of the wellhead assembly229and/or larger system.

In this example, the retention pins230are independently moveable within their respective channels251(also called tubing spool channels251herein) in the tubing spool250relative to the retention ring260. In other words, the retention pin driver (e.g., retention pin driver180) used to move the retention pins230within their respective channels251in the tubing spool250is used on one retention pin230at a time. Retention pin230-1, featured inFIGS.2B and2C, is shown as being captured by the retention pin receiving feature265-1within the tubing spool channel251-1. Retention pin230-2, featured inFIGS.2D and2E, is shown as being engaged with a channel289(also called a retention ring channel289herein) within the tubing spool channel251-2.

The retention pins230in this example are configured substantially the same as each other in this case. Each retention pin230is substantially cylindrically shaped and has a proximal end240, a distal end245, and a body243located between the proximal end240and the distal end245. Disposed on the outer perimeter of part of the body243of each retention pin230in this case are mating threads244. Also, there can be one or more channels253disposed in the body243axially around the outer perimeter of the body243. Each channel253in the body243can be configured to receive a sealing member270. Further, the distal end245of each retention pin230includes an engagement feature295that can be configured to be captured by one of the retention pin receiving features265located within one of the tubing spool channels251and subsequently engaged, when the retention pin230is moved inward within the tubing spool channel251, with one of the retention ring channels289. In addition, the proximal end240of each retention pin230can include a driver enablement feature241that is configured to engage with a retention pin driver (e.g., by a retention pin driver180).

For example, retention pin230-1has a proximal end240-1, a distal end245-1, and a body243-1located between the proximal end240-1and the distal end245-1. The body243-1of retention pin230-1has mating threads244-1disposed on a portion of the outer perimeter thereof. Further, channel253-1and channel253-2are disposed axially around the outer perimeter of the body243-1toward the distal end245-1. In this example, channel253-1receives a sealing member270-1, and channel253-2receives a sealing member270-2. Further, the distal end245-1of retention pin230-1includes an engagement feature295-1that is coupled to an adapter208-1, the collection of which is captured by retention pin receiving feature265-1disposed within the tubing spool channel251-1and subsequently engaged, when the retention pin230-1is moved inward within the tubing spool channel251-1, with the retention ring channel289-1in the retention ring260.

In addition, the proximal end240-1of retention pin230-1includes a driver enablement feature241-1(e.g., an octagonal cross-sectional shape along its outer surface, a hexagonal recess in the proximal end surface) that is configured to engage with a retention pin driver (e.g., by a retention pin driver180). The retention pin driver rotates the retention pin230-1, causing the mating threads244-1of the retention pin230-1to engage with the complementary mating threads254-1in part of the wall that forms the tubing spool channel251-1. A rotation of the retention pin230-1in a certain direction (e.g., clockwise) causes the retention pin230-1to move inward within the tubing spool channel251-1until the engagement feature295-1(and so also the adapter208-1) abut against the retention ring channel289-1of the retention ring260, thereby engaging the retention pin230-1. In this case, the retention pin230-1is not engaged.

Similarly, retention pin230-2has a proximal end240-2, a distal end245-2, and a body243-2located between the proximal end240-2and the distal end245-2. The body243-2of retention pin230-2has mating threads244-2disposed on a portion of the outer perimeter thereof. Further, channel253-3and channel253-4are disposed axially around the outer perimeter of the body243-2toward the distal end245-2. In this example, channel253-3receives a sealing member270-3, and channel253-4receives a sealing member270-4. Further, the distal end245-2of retention pin230-2includes an engagement feature295-2that is coupled to an adapter208-2, the collection of which is captured by retention pin receiving feature265-2disposed within the tubing spool channel251-2and subsequently engaged, when the retention pin230-2is moved inward within the tubing spool channel251-2, with the retention ring channel289-2in the retention ring260.

In addition, the proximal end240-2of retention pin230-2includes a driver enablement feature241-2that is configured to engage with a retention pin driver (e.g., by a retention pin driver180). The retention pin driver rotates the retention pin230-2, causing the mating threads244-2of the retention pin230-2to engage with the complementary mating threads254-2in part of the wall that forms the tubing spool channel251-2. A rotation of the retention pin230-2in a certain direction (e.g., clockwise) causes the retention pin230-2to move inward within the tubing spool channel251-2until the engagement feature295-2(and so also the adapter208-2) abut against the retention ring channel289-2of the retention ring260, thereby engaging the retention pin230-2. In this case, the retention pin230-2is engaged (also said to be in an engaged state herein).

In this case, the sealing members270(sealing member270-1, sealing member270-2, sealing member270-3, and sealing member270-4) can be configured to form an interference fit with the inner surface of the respective channel253in which the sealing member270is positioned. In alternative embodiments, one or more of the sealing members270can be configured to form some other type of seal (e.g., a compression seal) with the respective channel253in which the sealing member270is positioned.

Referring toFIGS.2B and2C, the engagement feature295-1of the retention pin230-1is shown to be coupled to the adapter208-1. The adapter208-1is an independent component that, when coupled to the engagement feature295-1at the distal end of the retention pin230-1, effectively increases the diameter and the length of the engagement feature295-1. In this way, the adapter208-1can be considered part of the engagement feature295-1. The engagement feature295-1at the distal end245-1of the retention pin230-1in this case is defined by a recess (designated by surface248-1) that separates an extension249-1at the distal end245-1from the remainder of the body243of the retention pin230-1. The diameter of the extension249-1, defined by the wall267-1, in this case is substantially the same as the diameter of the body243, and the diameter of the surface248-1for the recess is less than the diameter of the extension249-1.

Similarly, referring toFIGS.2D and2E, the engagement feature295-2of the retention pin230-2is shown to be coupled to the adapter208-2. The adapter208-2is an independent component that, when coupled to the engagement feature295-2at the distal end of the retention pin230-2, effectively increases the diameter and the length of the engagement feature295-2. In this way, the adapter208-2can be considered part of the engagement feature295-2. The engagement feature295-2at the distal end245-2of the retention pin230-2in this case is defined by a recess (designated by surface248-2) that separates an extension249-2at the distal end245-2from the remainder of the body243of the retention pin230-2. The diameter of the extension249-2in this case is substantially the same as the diameter of the body243, and the diameter of the surface248-2for the recess is less than the diameter of the extension249-2.

Each of the retention pin receiving features265in this case is located at the distal end of a tubing spool channel251. For example, as shown inFIG.2C, retention ring receiving feature265-1is located at the distal end of tubing spool channel251-1and is defined by a wall247-1that has a diameter that is larger than the diameter of the remainder of the tubing spool channel251-1. As another example, as shown inFIG.2E, retention ring receiving feature265-2is located at the distal end of tubing spool channel251-2and is defined by a wall247-2that has a diameter that is larger than the diameter of the remainder of the tubing spool channel251-2.

When the engagement feature295of a retention pin230, and so also the associated adapter208in this example, are positioned within a retention pin receiving feature265, the engagement feature295is said to be captured or in a captured state. In this case, the engagement feature295-1of retention pin230-1is captured by retention pin receiving feature265-1located at the distal end of tubing spool channel251-1, and the engagement feature295-2of retention pin230-2is captured by retention pin receiving feature265-2located at the distal end of tubing spool channel251-2.

When the engagement feature295of a retention pin230transitions to an engaged state, some or all of the portions of the engagement feature295that were positioned within the retention pin receiving feature265within the tubing spool channel251moves inward to become at least partially positioned outside of the tubing spool channel251and engages part of the adjoining retention ring channel289. In this case, engagement feature295-1and the associated adapter208-1are located entirely outside the retention ring channel289-1and entirely inside of the tubing spool channel251-1. As a result, engagement feature295-1and the associated adapter208-1are captured but not engaged. By contrast, engagement feature295-2and the associated adapter208-2are partially located within the retention ring channel289-2and partially within the tubing spool channel251-2. As a result, engagement feature295-2and the associated adapter208-2are captured and engaged.

In light of the above, referring toFIGS.2B and2C, the configuration of the retention pin receiving feature265-1of the tubing spool channel251-1complements the configuration of the engagement feature295-1and associated adapter208-1of the retention pin230-1. The adapter208-1includes a base269-1and an inward extension266-1at its distal end (away from the base269-1). The inward extension266-1is configured to extend into and, in some cases, abut against the wall247-1that forms the retention pin receiving feature265-1. As such, the characteristics (e.g., length, thickness, distance from the base269-1) of the inward extension266-1complement the corresponding characteristics (e.g., radius of the surface248-1, thickness of the recess defined by the surface248-1, distance of the recess from the distal end of the extension249-1) of the engagement feature295-1. As discussed above, the purpose of the adapter208-1is to increase one or more of the dimensions (e.g., the diameter, the thickness) of the engagement feature295-1to facilitate capture of the engagement feature295-1by the retention pin receiving feature265-1.

The engagement feature295-1and accompanying adapter208-1can move within the retention ring channel289-1in the retention ring260. When the tubing spool250, the tubing hanger220, and the retention ring260of the example tubing hanger retention system235are assembled into the wellhead assembly229, the retention pin receiving feature265-1at the distal end of the tubing spool channel251-1can be substantially aligned with the retention ring channel289-1. The diameter of the retention ring channel289-1, at least at its entrance (at its distal end) can be large enough to allow at least the distal end of the engagement feature295-1and accompanying adapter208-1to enter therein.

The top of the retention ring channel289-1can include one or more features262-1(e.g., a slot, planar surfaces) that complement the features of the base269-1of the engagement feature295-1. In this way, the engagement feature295-1can be sufficiently oriented with respect to the retention ring channel289-1and move (e.g., slide) therein. The retention ring channel289-1can also have a slanted bottom surface261-1that provides for a larger diameter at its distal end and a gradually decreasing diameter traveling inward through the retention ring channel289-1. By reducing (in this case, gradually) the size of the retention ring channel289-1from the distal end inward, the size of the retention ring channel289-1eventually becomes smaller than the size of the adapter208-1, causing the inward movement of the retention pin230-1to stop. At that point, the retention pin230-1becomes engaged with the retention ring channel289-1. The slanted bottom surface261-1can serve to complement a chamfer268-1(or other feature) in the outer distal surface of the base269-1of the engagement feature295-1.

Referring toFIGS.2D and2E, the configuration of the retention pin receiving feature265-2of the tubing spool channel251-2complements the configuration of the engagement feature295-2and associated adapter208-2of the retention pin230-2. The adapter208-2includes a base269-2and an inward extension266-2at its distal end (away from the base269-2). The inward extension266-2is configured to extend into and, in some cases, abut against the wall247-2that forms the retention pin receiving feature265-2. As such, the characteristics (e.g., length, thickness, distance from the base269-2) of the inward extension266-2complement the corresponding characteristics (e.g., radius of the surface248-2, thickness of the recess defined by the surface248-2, distance of the recess from the distal end of the extension249-2) of the engagement feature295-2. As discussed above, the purpose of the adapter208-2is to increase one or more of the dimensions (e.g., the diameter, the thickness) of the engagement feature295-2to facilitate capture of the engagement feature295-2by the retention pin receiving feature265-2.

The engagement feature295-2and accompanying adapter208-2can move within the retention ring channel289-2in the retention ring260. When the tubing spool250, the tubing hanger220, and the retention ring260of the example tubing hanger retention system235are assembled into the wellhead assembly229, the retention pin receiving feature265-2at the distal end of the tubing spool channel251-2can be substantially aligned with the retention ring channel289-2. The diameter of the retention ring channel289-2, at least at its entrance (at its distal end) can be large enough to allow at least the distal end of the engagement feature295-2and accompanying adapter208-2to enter therein.

The top of the retention ring channel289-2can include one or more features262-2(e.g., a slot, planar surfaces) that complement the features of the base269-2of the engagement feature295-2. In this way, the engagement feature295-2can be sufficiently oriented with respect to the retention ring channel289-2and move (e.g., slide) therein. The retention ring channel289-2can also have a slanted bottom surface261-2that provides for a larger diameter at its distal end and a gradually decreasing diameter traveling inward through the retention ring channel289-2. By reducing (in this case, gradually) the size of the retention ring channel289-2from the distal end inward, the size of the retention ring channel289-2eventually becomes smaller than the size of the adapter208-2, causing the inward movement of the retention pin230-2to stop. At that point, as shown inFIG.2E, the retention pin230-2becomes engaged with (becomes wedged against) the retention ring channel289-2. The slanted bottom surface261-2can serve to complement a chamfer268-2(or other feature) in the outer distal surface of the base269-2of the engagement feature295-2.

FIGS.3A through3Cshow various views of another wellhead assembly329that includes a tubing hanger retention system335with retention pins330in a captured position according to certain example embodiments.FIGS.4A through4Cshow various views of the wellhead assembly329ofFIGS.3A through3Cwith the retention pins330of the tubing hanger retention system335in an engaged position according to certain example embodiments. Specifically,FIG.3Ashows a front view of the part of the wellhead assembly329with the retention pins330of the tubing hanger retention system335in a captured state.FIG.3Bshows a detailed front view of part of the tubing hanger retention system335ofFIG.3Awith the retention pin330-1in the captured state.FIG.3Cshows a further detailed front view of part of the tubing hanger retention system335ofFIG.3Bwith the retention pin330-1in the captured state.FIG.4Ashows a front view of the part of the wellhead assembly329with the retention pins330of the tubing hanger retention system335in an engaged state.FIG.4Bshows a detailed front view of part of the tubing hanger retention system335ofFIG.4Awith the retention pin330-2in the engaged state.FIG.4Cshows a further detailed front view of part of the tubing hanger retention system335ofFIG.4Bwith the retention pin330-2in the engaged state.

Referring toFIGS.1through4C, the wellhead assembly329ofFIGS.3A through4Cincludes a tubing spool350, a tubing hanger320, a tubing string311, an upper wellhead317, the tubing hanger retention system335, multiple (in this case, two) valves313(valve313-1and valve313-2), and piping388. From the views provided inFIGS.3B,3C,4B, and4C, the tubing hanger retention system335includes a retention ring360, a retention pin driver380, and two retention pins330(retention pin330-1and retention pin330-2). The tubing spool350, the tubing hanger320, the tubing string311, the piping388, the valves313, the upper wellhead317, and the tubing hanger retention system335of the wellhead assembly329are substantially the same as the tubing spool150, the tubing hanger120, the tubing string111, the piping288, the valves213, the upper wellhead117, and the tubing hanger retention systems (e.g., tubing hanger retention system135, tubing hanger retention system235) of the wellhead assemblies (e.g., wellhead assembly129, wellhead assembly229) described above, except as discussed below.

One end of valve313-1is coupled to piping388that is directly coupled to the tubing spool350. The other end of valve313-1is coupled to additional piping388that leads to another component of the wellhead assembly329and/or larger system. Similarly, one end of valve313-2is coupled to piping388that is directly coupled to the tubing spool350. The other end of valve313-2is coupled to additional piping388that leads to another component of the wellhead assembly329and/or larger system.

In this example, the retention pins330are simultaneously moveable within their respective channels351(also called tubing spool channels351herein) in the tubing spool350relative to the retention ring360. In other words, the retention pin driver380used to move the retention pins330within their respective tubing spool channels351is used on all of the retention pins330at once. Retention pin330-1, featured inFIGS.3B and3C, is shown as being captured by the retention pin receiving feature365-1within the tubing spool channel351-1. Retention pin330-2, featured inFIGS.4B and4C, is shown as being engaged with a channel389(also called a retention ring channel389herein) within the tubing spool channel351-2.

The retention pin driver380has a body382that is disposed over the outer perimeter of the tubing spool350. In this case, there are mating threads384disposed on at least a portion of the inner surface of the body382of the retention pin driver380. The mating threads384of the retention pin driver380are configured to engage with the complementary mating threads356in part of the outer surface of the tubing spool350as the retention pin driver380rotates. A rotation of the retention pin driver380in a certain direction (e.g., clockwise) causes the retention pin driver380to move in one direction (e.g., downward) relative to the tubing spool250, while a rotation of the retention pin driver380in the opposite direction (e.g., counter-clockwise) causes the retention pin driver380to move in an opposite direction (e.g., upward) relative to the tubing spool250. The retention pin driver380has one or more features (in this case, a chamfered bottom end381, discussed below) that engage the retention pins330to move the retention pins330within their respective tubing spool channels351at substantially the same time.

The retention pins330in this example are configured substantially the same as each other in this case. Each retention pin330is substantially cylindrically shaped and has a proximal end340, a distal end345, and a body343located between the proximal end340and the distal end345. There are no mating threads (e.g., mating threads244) on the outer perimeter of any part of the body343of the retention pins330in this case. Also, there can be one or more channels353disposed in the body343axially around the outer perimeter of the body343. Each channel353in the body343can be configured to receive a sealing member370. Further, the distal end345of each retention pin330includes an engagement feature395that can be configured to be captured by one of the retention pin receiving features365located within one of the tubing spool channels351and subsequently engaged, when the retention pin330is moved inward within the tubing spool channel351, with one of the retention ring channels389. In addition, the proximal end340of each retention pin330can include a driver enablement feature341that is configured to engage with the retention pin driver380.

For example, retention pin330-1has a proximal end340-1, a distal end345-1, and a body343-1located between the proximal end340-1and the distal end345-1. There are no coupling features (e.g., mating threads) disposed on the outer perimeter of the body343-1of the retention pin330-1. Further, channel353-1is disposed axially around the outer perimeter of the body343-1toward the distal end345-1. In this example, channel353-1receives a sealing member370-1. Further, the distal end345-1of retention pin330-1includes an engagement feature395-1that is captured by retention pin receiving feature365-1disposed within the tubing spool channel351-1and subsequently engaged, when the retention pin330-1is moved inward within the tubing spool channel351-1, with the retention ring channel389-1in the retention ring360. There is no adapter (e.g., adapter208-1) for the engagement feature395-1in this case.

In addition, the proximal end340-1of retention pin330-1includes a driver enablement feature341-1(e.g., a chamfered outer end) that is configured to engage with the retention pin driver380, which in this case includes a chamfered bottom end381that complements the chamfered outer end of the driver enablement feature341-1. In this case, as the retention pin driver380rotates in a particular direction (e.g., downward) relative to the tubing spool350, the chamfered bottom end381the retention pin driver380contacts the driver enablement feature341-1of the retention pin330-1. As the retention pin driver380continues its movement in the same direction, the chamfered bottom end381pushes the retention pin330-1, through the driver enablement feature341-1, inward within the tubing spool channel351-1. This inward movement of the retention pin330-1within the tubing spool channel351-1can continue until the engagement feature395-1abuts against the retention ring channel389-1of the retention ring360, thereby engaging the retention pin330-1. In this case, the retention pin330-1, while captured, is not engaged.

The retention pin330-1also includes an extension379-1that extends laterally away from the body343toward the proximal end340-1of the retention pin330-1. The extension379-1has a diameter that is substantially the same as, or slightly smaller than, the diameter of a recess344-1toward the proximal end of the tubing spool channel351-1. The recess344-1in the tubing spool channel351-1is longer than the length of the extension379-1of the extension pin330-1. Also, the diameter of the recess344-1in the tubing spool channel351-1is greater than the diameter of the extension379-1of the extension pin330-1. In this way, the extension379-1can move within the recess344-1as the retention pin330-1moves within the tubing spool channel351-1. The length of the recess344-1can be large enough to receive the extension379-1for the entire possible range of motion of the retention pin330-1within the tubing spool channel351-1.

In some cases, as in this example, the retention pin330-1can also include a resilient device354-1disposed around the body343between the extension379-1and the extension349-1of the engagement feature395-1. In such a case, the resilient device354-1can be positioned adjacent to the extension379-1toward the proximal end of the retention pin330-1. The resilient device354-1can be configured to transition, potentially multiple times, between a default state (as when the retention pin330-1is in a captured state but not in an engaged state, as shown in FIG.3C) and a compressed state (as when the retention pin330(e.g., retention pin330-2) is in a captured state and an engaged state, as shown inFIG.4C). Examples of a resilient device354-1can include, but are not limited to, a conical spring washer, a Belleville washer, a coned-disc spring, a disc spring, a Belleville spring, a cupped spring washer, and a compression spring.

Similarly, retention pin330-2has a proximal end340-2, a distal end345-2, and a body343-2located between the proximal end340-2and the distal end345-2. There are no coupling features (e.g., mating threads) disposed on the outer perimeter of the body343-2of the retention pin330-2. Further, channel353-2is disposed axially around the outer perimeter of the body343-2toward the distal end345-2. In this example, channel353-2receives a sealing member370-2. Further, the distal end345-2of retention pin330-2includes an engagement feature395-2that is captured by retention pin receiving feature365-2disposed within the tubing spool channel351-2and subsequently engaged, when the retention pin330-2is moved inward within the tubing spool channel351-2, with the retention ring channel389-2in the retention ring360. There is no adapter (e.g., adapter208-2) for the engagement feature395-2in this case.

In addition, the proximal end340-2of retention pin330-2includes a driver enablement feature341-2(e.g., a chamfered outer end) that is configured to engage with the retention pin driver380, which in this case includes a chamfered bottom end381that complements the chamfered outer end of the driver enablement feature341-2. In this case, as the retention pin driver380rotates in a particular direction (e.g., downward) relative to the tubing spool350, the chamfered bottom end381the retention pin driver380contacts the driver enablement feature341-2of the retention pin330-2. As the retention pin driver380continues its movement in the same direction, the chamfered bottom end381pushes the retention pin330-2, through the driver enablement feature341-2, inward within the tubing spool channel351-2. This inward movement of the retention pin330-2within the tubing spool channel351-2can continue until the engagement feature395-2abuts against the retention ring channel389-2of the retention ring360, thereby engaging the retention pin330-2. In this case, the retention pin330-2is engaged as well as captured.

The retention pin330-2also includes an extension379-2that extends laterally away from the body343toward the proximal end340-2of the retention pin330-2. The extension379-2has a diameter that is substantially the same as, or slightly smaller than, the diameter of a recess344-2toward the proximal end of the tubing spool channel351-2. The recess344-2in the tubing spool channel351-2is longer than the length of the extension379-2of the extension pin330-2. Also, the diameter of the recess344-2in the tubing spool channel351-2is greater than the diameter of the extension379-2of the extension pin330-2. In this way, the extension379-2can move within the recess344-2as the retention pin330-2moves within the tubing spool channel351-2. The length of the recess344-2can be large enough to receive the extension379-2for the entire possible range of motion of the retention pin330-2within the tubing spool channel351-2.

In some cases, as in this example, the retention pin330-2can also include a resilient device354-2disposed around the body343between the extension379-2and the extension349-2of the engagement feature395-2. In such a case, the resilient device354-2can be positioned adjacent to the extension379-2toward the proximal end of the retention pin330-2. The resilient device354-2can be configured to transition, potentially multiple times, between a default state (as when the retention pin330-2is in a captured state but not in an engaged state, as shown inFIG.3Cwith respect to the retention pin330-1) and a compressed state (as when the retention pin330-2is in a captured state and an engaged state, as shown inFIG.4C). The resilient device354-2can be substantially the same as the resilient device354-1discussed above.

In this case, the sealing members370(sealing member370-1and sealing member370-2) can be configured to form an interference fit with the inner surface of the respective channel353in which the sealing member370is positioned. In alternative embodiments, one or more of the sealing members370can be configured to form some other type of seal (e.g., a compression seal) with the respective channel353in which the sealing member370is positioned.

Referring toFIGS.3B and3C, the engagement feature395-1of the retention pin330-1is configured in such a way that an adapter (e.g., adapter208-1) is not needed. The engagement feature395-1at the distal end345-1of the retention pin330-1in this case is defined by an extension349-1that has a diameter that is substantially the same as, or slightly smaller than, the diameter of the retention ring receiving feature365-1located at the distal end of tubing spool channel351-1and defined by wall347-1. Also, the thickness of the extension349-1of the engagement feature395-1in this case is substantially the same as, or slightly smaller than, the length of the wall347-1that defines the thickness of the retention ring receiving feature365-1.

Each of the retention pin receiving features365in this case is located at the distal end of a tubing spool channel351. For example, as shown inFIG.3C, retention ring receiving feature365-1is located at the distal end of tubing spool channel351-1, and the wall347-1that defines the retention ring receiving feature365-1has a diameter that is larger than the diameter of the remainder of the tubing spool channel351-1. As another example, as shown inFIG.4C, retention ring receiving feature365-2is located at the distal end of tubing spool channel351-2, and the wall347-2that defines the retention ring receiving feature365-2has a diameter that is larger than the diameter of the remainder of the tubing spool channel351-2.

When the engagement feature395of a retention pin330is positioned within a retention pin receiving feature365, the engagement feature395is said to be captured or in a captured state. In this case, the engagement feature395-1of retention pin330-1is captured by retention pin receiving feature365-1located at the distal end of tubing spool channel351-1, and the engagement feature395-2of retention pin330-2is captured by retention pin receiving feature365-2located at the distal end of tubing spool channel351-2.

When the engagement feature395of a retention pin330transitions to an engaged state, some or all of the portions of the engagement feature395that were positioned within the retention pin receiving feature365within the tubing spool channel351moves inward to become positioned at least partly outside of the tubing spool channel351and engages part of the adjoining retention ring channel389. In this case, engagement feature395-1is located entirely outside the retention ring channel389-1and entirely inside of the tubing spool channel351-1. As a result, engagement feature395-1is captured but not engaged. By contrast, engagement feature395-2is partially located within the retention ring channel289-2and partially within the tubing spool channel251-2. As a result, engagement feature395-2is captured and engaged.

In light of the above, referring toFIGS.3B and3C, the configuration of the retention pin receiving feature365-1of the tubing spool channel351-1complements the configuration of the engagement feature395-1of the retention pin330-1. The extension349-1of the engagement feature395-1in this case extends into the retention pin receiving feature365-1and abuts against the wall347-1that forms the retention pin receiving feature365-1. As such, the characteristics (e.g., length, thickness) of the extension349-1of the engagement feature395-1complement the corresponding characteristics (e.g., length of the wall347-1, diameter) of the retention pin receiving feature365-1.

The engagement feature395-1can move within the retention ring channel389-1in the retention ring360. When the tubing spool350, the tubing hanger320, and the retention ring360of the example tubing hanger retention system335are assembled into the wellhead assembly329, the retention pin receiving feature365-1at the distal end of the tubing spool channel351-1can be substantially aligned with the retention ring channel389-1of the retention ring360. The diameter of the retention ring channel389-1, at least at its entrance (at its distal end) can be large enough to allow at least the distal end of the engagement feature395-1to enter therein.

The top of the retention ring channel389-1can include one or more features362-1(e.g., a slot, planar surfaces) that complement the features of the extension349-1of the engagement feature395-1. In this way, the engagement feature395-1can be sufficiently oriented with respect to the retention ring channel289-1and move (e.g., slide) therein. The retention ring channel389-1can also have a slanted bottom surface361-1that provides for a larger diameter at its distal end and a gradually decreasing diameter traveling inward through the retention ring channel389-1. By reducing (in this case, gradually) the size of the retention ring channel389-1from the distal end inward, the size of the retention ring channel389-1eventually becomes smaller than the size of the engagement feature395-1, causing the inward movement of the retention pin330-1to stop. At that point, the retention pin330-1becomes engaged with the retention ring channel389-1. The slanted bottom surface361-1can serve to complement a chamfer368-1(or other feature) in the outer distal surface of the extension349-1of the engagement feature395-1.

Referring toFIGS.4B and4C, the configuration of the retention pin receiving feature365-2within the tubing spool channel351-2complements the configuration of the engagement feature395-2of the retention pin330-2. The extension349-2of the engagement feature395-2in this case extends into the retention pin receiving feature365-2and abuts against the wall347-2that forms the retention pin receiving feature365-2. As such, the characteristics (e.g., length, thickness) of the extension349-2of the engagement feature395-2complement the corresponding characteristics (e.g., length of the wall347-2, diameter) of the retention pin receiving feature365-2.

The engagement feature395-2can move within the retention ring channel389-2in the retention ring360. When the tubing spool350, the tubing hanger320, and the retention ring360of the example tubing hanger retention system335are assembled into the wellhead assembly329, the retention pin receiving feature365-2at the distal end of the tubing spool channel351-2can be substantially aligned with the retention ring channel389-2of the retention ring360. The diameter of the retention ring channel389-2, at least at its entrance (at its distal end) can be large enough to allow at least the distal end of the engagement feature395-2to enter therein.

The top of the retention ring channel389-2can include one or more features362-2(e.g., a slot, planar surfaces) that complement the features of the extension349-2of the engagement feature395-2. In this way, the engagement feature395-2can be sufficiently oriented with respect to the retention ring channel289-2and move (e.g., slide) therein. The retention ring channel389-2can also have a slanted bottom surface361-2that provides for a larger diameter at its distal end and a gradually decreasing diameter traveling inward through the retention ring channel389-2. By reducing (in this case, gradually) the size of the retention ring channel389-2from the distal end inward, the size of the retention ring channel389-2eventually becomes smaller than the size of the engagement feature395-2, causing the inward movement of the retention pin330-2to stop. At that point, as shown inFIG.4C, the retention pin330-2becomes engaged with the retention ring channel389-2. The slanted bottom surface361-2can serve to complement a chamfer368-2(or other feature) in the outer distal surface of the extension349-2of the engagement feature395-2.

In some cases, the engagement feature395of a retention pin330can be of a fixed shape and size. In cases such as this, where the diameter of the engagement feature395is larger than the diameter of the body343of the retention pin330, the retention pin330needs to be inserted into the tubing spool channel351of the tubing spool350before the tubing spool350is assembled with the wellhead assembly329. Alternatively, the engagement feature395of a retention pin330can be expandable. In such a case, the engagement feature395can initially be contracted so that the diameter of the engagement feature is no greater than the diameter of the body343of the retention pin330. This allows the retention pin330to be inserted into a tubing spool channel351from the outside. Once the engagement feature395is positioned within the retention pin receiving feature365disposed in the tubing spool channel351, the engagement feature395can be expanded and captured by the retention pin receiving feature365.

FIG.5shows a flowchart510for a method of securing retention pins in a wellhead assembly according to certain example embodiments. While the various steps in this flowchart510are presented sequentially, one of ordinary skill will appreciate that some or all of the steps may be executed in different orders, may be combined or omitted, and some or all of the steps may be executed in parallel. Further, in one or more of the example embodiments, one or more of the steps shown in this example method may be omitted, repeated, and/or performed in a different order. Some or all of the steps of the method ofFIG.5can be performed off site (e.g., at a manufacturing facility, at a staging area). In addition, or in the alternative, some or all of the steps of the method ofFIG.5can be performed on site (e.g., in the field, adjacent to a wellbore123) where a field operation is being performed or planned.

In addition, a person of ordinary skill in the art will appreciate that additional steps not shown inFIG.5may be included in performing this method. Accordingly, the specific arrangement of steps should not be construed as limiting the scope. Further, a particular computing device, such as a controller104discussed above with respect toFIG.1, can be used to perform one or more of the steps (or portions thereof) for the method shown inFIG.5in certain example embodiments. Any of the functions performed below by a controller404can involve the use of one or more protocols, one or more algorithms, and/or stored data stored in a storage repository. In addition, or in the alternative, any of the functions in the method can be performed by a user (e.g., user175), which may include an associated user system (e.g., user system176).

The method shown inFIG.5is merely an example that can be performed by using an example system described herein. In other words, systems for securing retention pins in a wellhead assembly can perform other functions using other methods in addition to and/or aside from those shown inFIG.5. Referring toFIGS.1through5, the method shown in the flowchart510ofFIG.5begins at the START step and proceeds to step521, where a retention pin (e.g., retention pin230, retention pin330) is inserted into a tubing spool channel (e.g., tubing spool channel251, tubing spool channel351) of a tubing spool (e.g., tubing spool250, tubing spool350).

The retention pin can be inserted into the tubing spool channel using a retention pin driver (e.g., retention pin driver180), which can be operated by a user (e.g., user175), a user system (e.g., user system176), and/or a controller (e.g., controller104). When the retention pin is inserted, the retention pin can be pushed, rotated, and/or otherwise moved within the tubing spool channel. In certain example embodiments, the retention pin is inserted into the tubing spool channel until the engagement feature (e.g., engagement feature295, engagement feature395) is captured by the retention pin receiving feature (e.g., retention pin receiving feature165, retention pin receiving feature265, retention pin receiving feature365) of the tubing spool channel.

In step522, a determination is made as to whether the retention pin (and more specifically, the engagement feature of the retention pin) is captured by the retention pin receiving feature of the tubing spool channel. The determination can be made using measurements made by one or more sensor devices (e.g., sensor device185). The determination can be made by a user, a user system, and/or a controller. If the retention pin is captured by the retention pin receiving feature, then the process proceeds to step524. If the retention pin is not captured by the retention pin receiving feature, then the process reverts to step521, where the retention pin continues to be inserted into the tubing spool channel.

In step524, a determination is made as to whether all of the retention pins are captured. As discussed above, a tubing spool can have multiple tubing spool channels, and each tubing spool channel is configured to receive a retention pin. For example, a tubing spool can have 24 tubing spool channels to receive 24 retention pins. In some cases, the retention pins can be inserted simultaneously, as shown inFIGS.3A through4C. In other cases, each retention pin is inserted individually, as shown inFIGS.2A through2E. The determination as to whether all of the retention pins are captured can be made using measurements made by one or more sensor devices. The determination as to whether all of the retention pins are captured can be made by a user, a user system, and/or a controller. If all of the retention pins are captured, then the process proceeds to step525. If all of the retention pins are not captured, then the process reverts to step521so that the retention pins not yet captured can be inserted into their respective tubing spool channels.

In step525, a retention pin is moved inward within the tubing spool channel to enter a retention ring channel (e.g., retention ring channel289, retention ring channel389) of a retention ring (e.g., retention ring160, retention ring260, retention ring360). The retention pin can be inserted further into the tubing spool channel using a retention pin driver, which can be operated by a user, a user system, and/or a controller. The retention pin driver used in this step525can be the same as, or different than, the retention pin driver used in step521above. When the retention pin is inserted, the retention pin can be pushed, rotated, and/or otherwise moved within the tubing spool channel. In certain example embodiments, the retention pin is moved inward to such an extent that the engagement feature of the retention pin leaves the tubing spool channel and enters the adjacent retention ring channel until the engagement feature engages (e.g., abuts against) a wall (e.g., the slanted bottom surface261, the slanted bottom surface361) of the retention ring channel.

In step526, a determination is made as to whether the retention pin (and more specifically, the engagement feature of the retention pin) is engaged with the retention ring channel of the retention ring. The determination can be made using measurements made by one or more sensor devices. The determination can be made by a user, a user system, and/or a controller. If the retention pin is engaged with the retention ring channel of the retention ring, then the process proceeds to step528. If the retention pin is not engaged with the retention ring channel of the retention ring, then the process reverts to step525, where the retention pin continues to be moved inward within the tubing spool channel.

In step528, a determination is made as to whether all of the retention pins are engaged. As discussed above, in some cases, the retention pins can be moved inward within the tubing spool channels simultaneously, as shown inFIGS.3A through4C. In other cases, each retention pin is moved inward within a tubing spool channel individually, as shown inFIGS.2A through2E. The determination as to whether all of the retention pins are engaged can be made using measurements made by one or more sensor devices. The determination as to whether all of the retention pins are engaged can be made by a user, a user system, and/or a controller. If all of the retention pins are engaged, then the process proceeds to the END step. If all of the retention pins are not engaged, then the process reverts to step525so that the retention pins not yet engaged can be moved inward within their respective tubing spool channels.

In some cases, example embodiments may be directed to a tubing hanger retention system for a wellhead assembly. In such cases, the engagement feature at the distal end of each retention pin may have a larger diameter relative to a diameter of a remainder of the retention pin. In addition, or in the alternative, in such cases, each retention ring channel may narrow from its distal end inward.

In some cases, example embodiments may be directed to a method for securing retention pins in a wellhead assembly. In such cases, the method may include moving, using a retention pin driver, a plurality of retention pins inward within a plurality of tubing spool channels in a tubing spool of the wellhead assembly. In certain example embodiments, the retention pin driver may engage a proximal end of each of the plurality of retention pins to rotate the retention pin further inward within the channel. In addition, or in the alternative, the retention pin driver may comprise a collar movably disposed around an outer perimeter of the tubing spool, where the collar moves over the proximal end of each of the plurality of retention pins, and where the collar moves the plurality of retention pins further inward within the plurality of tubing spool channels when the collar moves over the proximal end of each of the plurality of retention pins.

In some cases, example embodiments may be directed to a retention ring of a tubing hanger retention system for a wellhead assembly. In such cases, the retention ring may include a body that is configured to be disposed over a top portion of a tubing hanger of the wellhead assembly. Further, the retention ring may include a plurality of retention ring channels positioned toward an outer perimeter of the body, where each of the plurality of retention ring channels is configured to engage an engagement feature disposed at a distal end of one of a plurality of retention pins when the one of the plurality of retention pins is moved inward within a tubing spool channel of a tubing spool of the wellhead assembly.

In some cases, example embodiments may be directed to a retention pin of a tubing hanger retention system for a wellhead assembly. The retention pin may include a body having an elongated shape with an outer perimeter that is configured to be movably disposed within a tubing spool channel of a tubing spool. Further, the retention pin may include a driver enablement feature disposed at a distal end of the body, where the driver enablement feature is configured to engage with a retention pin driver, where the retention pin driver is configured to move the body within the tubing spool channel. In addition, the retention pin may include an engagement feature disposed at a distal end of the body, where the engagement feature is configured to be captured by a retention pin receiving feature disposed in the tubing spool channel, and where the engagement feature is further configured to be engaged by a retention ring channel of a retention ring of the tubing hanger retention system when the body is moved inward within the tubing spool channel.

In some cases, the retention pin may also include an extension disposed toward a proximal end of the body, where the extension has a first diameter that is larger than a second diameter of the body. Further, in some cases, the retention pin may also include a resilient device disposed around the body proximate to the extension, where the resilient device is configured to apply a compressive force against the extension when the body is moved inward within the tubing spool channel.

In some cases, example embodiments may be directed to a tubing spool for a wellhead assembly. The tubing spool may include a body. Further, the tubing spool may include a plurality of tubing spool channels disposed through the body, where each tubing spool channel is configured to receive a retention pin that is movable therein, where each tubing spool channel has a retention pin receiving feature disposed at its distal end, and where the retention pin receiving feature is configured to capture an engagement feature at a distal end of each retention pin as the retention pin moves within the tubing spool channel. In certain example embodiments, each tubing spool channel may further have a recess disposed at its proximal end, and the recess may be configured to receive a resilient device.

Example embodiments can be used to safely and reliably retain the tubing hanger within a wellhead assembly. Example embodiments can use multiple retention pins, a retention ring, and features in the tubing spool channels of the tubing spool. The retention pins are first captured, and subsequently engaged. The retention pins can be engaged simultaneously or a different times. Example embodiments can be used for any of a number of field operations at various pressures, flow rates, and temperatures. Example embodiments can provide a number of benefits. Such benefits can include, but are not limited to, ease of use, reduction in costs, improved safety and reliability, ease of disassembly, reduced need of specialized equipment, configurability, time savings, and compliance with applicable industry standards and regulations.

Although embodiments described herein are made with reference to example embodiments, it should be appreciated by those skilled in the art that various modifications are well within the scope and spirit of this disclosure. Those skilled in the art will appreciate that the example embodiments described herein are not limited to any specifically discussed application and that the embodiments described herein are illustrative and not restrictive. From the description of the example embodiments, equivalents of the elements shown therein will suggest themselves to those skilled in the art, and ways of constructing other embodiments using the present disclosure will suggest themselves to practitioners of the art. Therefore, the scope of the example embodiments is not limited herein.