ANTI-EXTRUSION DEVICE WITH INTEGRAL PLATE AND LATTICE FOR CASING HANGER ANNULAR SEAL

Abstract

System and methods are disclosed herein for an anti-extrusion device for oil and gas equipment. The anti-extrusion device may include an annular lattice structure and an annular plate integrated with the annular lattice structure. The anti-extrusion device may be used with an elastomer annular seal so that, when the elastomer annular seal is energized, the annular lattice structure is to deform and is to prevent the elastomer annular seal from extruding into extrusion gaps of the oil and gas equipment.

Description

BACKGROUND

1. Technical Field

This disclosure relates generally to oil and gas equipment and more particularly to anti-extrusion devices for casing hanger annular seal.

2. Description of the Prior Art

A slip hanger, such as a manual slip hanger, is a type of wellhead equipment used with oil and gas equipment to support the weight of oilfield tubulars or strings in a wellbore; these oilfield tubulars may be a casing or tubing strings. The slip hanger may be installed within the wellhead and may include a series of slips that grip a casing string. A housing may be provided to hold the slip hanger in place. Further, a mechanism may be provided within the slip hanger for releasing and setting the slips. The slip hanger may be used in conjunction with a casing or tubing head, which may form part of a wellhead via a flanged, threaded, or other type of mechanical connection. The casing or tubing head may be referred to as a casing head herein, and the tubular may be referred to as a casing string. The casing head includes a bore that may be slightly larger than the casing string, which allows the casing string to be run through it. The slip hanger may be placed within the casing head and the slips may be set to grip the casing string. For removal of the casing string, slips may be released by releasing the casing tension and the casing string can be pulled out of the wellbore. In a similar manner, a packoff is a mechanical seal used in oil and gas equipment to prevent fluid leakage between sections of the equipment, such as to isolate the annulus volume from a bore volume in a wellhead. In all such applications, elastomer annular seals may be used. A nature of extrusion of elastomer annual seals may occur at extrusion gaps between metallic components of the oil and gas equipment. This may be prevalent at least under high pressure and high temperature applications.

SUMMARY

An anti-extrusion device for oil and gas equipment may include an annular lattice structure. The anti-extrusion device may be used with an elastomer annular seal. When the elastomer annular seal is energized, the annular lattice structure is to deform and to prevent the elastomer annular seal from extruding into extrusion gaps of the oil and gas equipment.

In at least one example, a system for oil and gas equipment may include an anti-extrusion device having an annular lattice structure. The system may also include an annular plate integrated with the annular lattice structure. The anti-extrusion device may be used with an elastomer annular seal. When the elastomer annular seal is energized, one or more of the annular lattice structure or the annular plate is to deform and is to prevent the elastomer annular seal from extruding into extrusion gaps of the oil and gas equipment.

In another example, an anti-extrusion device may include an annular lattice structure and an annular plate integrated with the annular lattice structure. The anti-extrusion device may be used in an oil and gas equipment with an elastomer annular seal. This may be so that, when the elastomer annular seal is energized, one or more of the annular lattice structure or the annular plate is to deform and is to prevent the elastomer annular seal from extruding into extrusion gaps of the oil and gas equipment.

In yet another example, a method for oil and gas equipment may include a step to determine an application in the oil and gas equipment comprising an elastomer annular seal. The method may include a step to form an anti-extrusion device for the application. The anti-extrusion device may include an annular lattice structure and an annular plate integrated with the annular lattice structure. The method may include energizing the elastomer annular seal within the oil and gas equipment to cause, in part, one or more of the annular lattice structure or the annular plate to deform and to prevent the elastomer annular seal from extruding into extrusion gaps of the oil and gas equipment.

BRIEF DESCRIPTION OF DRAWINGS

Some of the features and benefits of the present disclosure having been stated, others will become apparent as the description proceeds when taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a block diagram of certain oil and gas equipment that is subject to a slip hanger or a packoff having an anti-extrusion device with an annular lattice structure and an annular plate integrated with the annular lattice structure, as detailed herein and in accordance with at least one example.

FIG. 2 is a perspective view of aspects of a slip hanger or a packoff subject to the anti-extrusion device, in accordance with at least one example.

FIG. 3A is a perspective view of aspects of a slip hanger or a packoff within a spool, in accordance with at least one example.

FIG. 3B is a cross-sectional perspective view of aspects of a slip hanger or a packoff within a spool, in accordance with at least one example.

FIG. 4A is a side cross-section view of aspects of a slip hanger or a packoff with the anti-extrusion device in a landed position, in accordance with at least one example.

FIG. 4B illustrates details of anti-extrusion devices in a landed position, in accordance with at least one example.

FIG. 4C illustrates details of loads, deformation, and movement in all or part of the anti-extrusion device in an energized or engaged position, in accordance with at least one example.

FIG. 4D is a detailed side cross-section view of aspects of an elastomer annular seal with an anti-extrusion device in a landed position, in accordance with at least one example.

FIG. 4E is a detailed perspective view of aspects of an elastomer annular seal with an anti-extrusion device, in accordance with at least one example.

FIG. 5A illustrates general and specific views of an annular lattice structure having structural elements in the format of an array of cells having voids that are filled voids, in accordance with at least one example.

FIG. 5B illustrates different formats of structural elements used to form the annular lattice structures, relative to FIG. 5A, in accordance with at least one example.

FIG. 5C illustrates a further format of structural elements used to form an annular lattice structure, in accordance with at least one example.

FIG. 5D illustrates further formats of structural elements used to form an annular lattice structure, in accordance with at least one example.

FIG. 6 is a flow diagram of a method for a system of a slip hanger or a packoff having an anti-extrusion device with an annular lattice structure and an annular plate integrated with the annular lattice structure, described at least in FIGS. 1-5D herein, in accordance with at least one example.

While the disclosure will be described in connection with the preferred examples, it will be understood that it is not intended to limit the disclosure to that example. On the contrary, it is intended to cover all alternatives, modifications, and equivalents, as may be included within the spirit and scope of the disclosure as defined by the appended claims.

DETAILED DESCRIPTION

The foregoing aspects, features and advantages of the present technology will be further appreciated when considered with reference to the following description of preferred examples and accompanying drawings, wherein like reference numerals represent like elements. In describing the preferred examples of the technology illustrated in the appended drawings, specific terminology will be used for the sake of clarity. The present technology, however, is not intended to be limited to the specific terms used, and it is to be understood that each specific term includes equivalents that operate in a similar manner to accomplish a similar purpose.

In at least one example, to resolve issues, such as described above, a slip hanger or packoff herein is provided with an anti-extrusion device having an annular lattice structure and an integrated annular plate. The annular lattice structure may also be integral with an elastomer annular seal and may include a repeating pattern of structural elements. The repeating pattern may be a substantially predetermined pattern that may be based in part on a specific application of the slip hanger or packoff. When the elastomer annular seal is energized, one or more of the annular lattice structure or the annular plate may deform to reduce a size of extrusion gaps in an oil and gas equipment of the application. In one example, one or more of the annular plate or the annular lattice structure may be forced to deform (such as, radially, which is used interchangeably with circumferentially unless otherwise indicated), which may include expanding away from the elastomer annular seal.

In one example, the annular plate may be solid, segmented, and/or may be provided in layers. The annular lattice structure may include elastomer or other materials that may be provided to fill voids formed by the structural elements in a manufacturing process prior to use in the application. The deformation to one or more of the annular plate or the annular lattice structure may fill the extrusion gaps in the application and may prevent the elastomer annular seal from extruding into the extrusion gaps. Further, a segmented annular plate can reduce a load required for energizing the elastomer annular seal, while a solid annular plate may have higher load requirements, in at least one example. Different applications may use different formats or versions of the anti-extrusion device described herein. In one example, the solid annular plate may be integrated with the annular lattice structure in a similar manner as the segmented annular plate. When layers are used, each layer may be integrated to a prior layer with at least one layer integrated to the annular lattice structure. There may be a layer gap between the layers. The solid or segmented annular plate and any layers, if provided, may be a base for the annular lattice structure.

In one example, upon energizing of the elastomer annular seal, deformation of one or more of the annular lattice structure or the annular plate ensures that axial seal extrusion resistance may be maximized for the elastomer annular seal. In addition, because the annular lattice structure is of actual geometry, finite element analysis (FEA) simulations may be used to predict a behavior of the anti-extrusion device, used within an application, with great confidence and accuracy.

While anti-extrusion device may be created using a woven sock that is compressed to form a wire mesh and that may be then molded with an elastomer annular seal, the wire mesh remains as individual fibers having ends. The individual fibers may be random and unorganized, relative to the annular lattice structure herein. The wire mesh may be nearly impossible to simulate and maintain as predictable because of material properties, including because individual fibers of the wire mesh may be in a chaotic array.

A wire mesh may also include a solid member to further strengthen the extrusion resistance, but this may cause a larger cross-section of a wire mesh required to prevent extrusion. This may add unwanted stiffness that may resist an elastomer annular seal from being energized. The annular lattice structure herein may be supported by modern additive manufacture methods to provide a single uniform anti-extrusion device with predictable material properties that are tuned with maximum predetermined extrusion resistance and with minimal setting loads. The annular lattice structure may allow an overall footprint of the anti-extrusion device to be shorter in height, which may save material to manufacture. This can also shorten an overall height required for the elastomer annular seal and for the slip hanger or packoff. This can also allow for shorter research and development (R&D) cycles, with fewer tests needed because of a known and predictable geometry used in the annular lattice structure.

The FEA simulations allow various annular lattice structures having arrays of cells of different patterns and sizes, which can be used to maintain the same extrusion resistance as wire mesh, with only 20% of the material. This allows a reduction in the size of the anti-extrusion device itself, along with one or more of the slip hanger or packoff or the elastomer annular seal. The annular lattice structures herein may be formed to create a known geometry with known material properties, that is integral with the annular plate(s) and, optionally, with the elastomer annular seal.

The use of the annular lattice structures having structural elements with filled voids may predictably allow reduction to larger extrusion gaps and may support pressure loads with minimal setting loads than otherwise possible. In addition, an automatic function, from the deformation allowed in the annular lattice structures, may eliminate a touch time or tools required for energizing or engaging components in the oil and gas equipment. There may be reduced manufacturing costs as the anti-extrusion device may include a single piece print or formed features in the oil and gas equipment. In one example, existing oil and gas equipment may be retrofitted using the anti-extrusion device with existing elastomer annular seals and/or slip hangers to improve performance.

FIG. 1 is a block diagram of certain oil and gas equipment 100 that is subject to a slip hanger or a packoff having an anti-extrusion device with an annular lattice structure and an annular plate integrated with the annular lattice structure, as detailed herein and in accordance with at least one example. The oil and gas equipment 100 may include a Christmas tree 130 over a wellhead 120 located at or about a surface layer 140. The Christmas tree 130 may include one or more branches 102 having valves thereon of the oil and gas equipment 100.

Further, as illustrated in FIG. 1, the oil and gas equipment 100 may include a top connector 112 that is connected at a top of a studded cross 104. There may be multiple flow line gate valves and multiple kill line gate valves, generally illustrated as valves 106. These valves 106 may be on opposite sides of a studded cross 104. Further, the oil and gas equipment may include one or more master gate valves 108, such as an upper and a lower master gate valve. A tubing head adapter may be connected between a tubing head 110 and at least one of the master gate valves 108.

In at least one example, a system 114 for a slip hanger or a packoff may be used to perform operations associated with a tubular or casing 116 and may be located within a casing hanger spool 118, which may be part of or associated with a housing of a wellhead 120. In at least one example, a system 114 of a slip hanger having inner bowl segments to go along with the slip segments (at least one slip segment 408 is illustrated in FIG. 4A). The slip segments and the inner bowl segments may be held together, in part, by the use of pins or fasteners and may be used to perform operations associated with a tubular or casing 116. Aspects of a packoff may be located within a tubing head 110 of the oil and gas equipment 100, and may be used to perform other operations associated with the tubular or casing 116.

In at least one example, a system 114 of a packoff may be used with other hangers, including a tubing hanger associated with a tubing, a production casing hanger associated with a production casing, or an intermediate casing hanger associated with an intermediate casing. Therefore, the illustrated tubular or casing 116 may be a series of concentric oilfield tubulars (casing or tubing), each having an independent hanger that may benefit from the present system of an anti-extrusion device with an annular lattice structure and an annular plate integrated with the annular lattice structure. Reference to the system may include reference to a slip hanger or a packoff and the reference numbers may be interchangeably used, unless otherwise specified herein.

In at least one example, a casing string may line walls of a wellbore 122 and may be supported by a slip hanger mounted to a wellhead 120, but may include associations to one or more of a casing hanger spool 118 or another feature. The slip hanger system may be referred to also as a casing hanger. In at least one example, wedge-shaped segmented slips or slip segments (such as in FIG. 4A) may be provided for coupling between the slip hanger and the tubular or casing 116. The slip segments may have an inner profile that is textured and an outer profile that is smooth. This is detailed further in at least FIG. 4A herein. Further, compression seal assemblies may be provided for preventing pressure communication and may be provided between the tubular or casing 116 and wellhead 120.

In at least one example, a system 114 of a slip hanger or a system 124 of a packoff may include multiple bowl segments to support multiple slip segments on an inner side. Further, the bowl segments may include at least a first retention feature to enable association with at least a second retention feature of the slip bowl to bring together the bowl segments. For example, the retention features may include fasteners or shoulders that interface to transfer load to a load shoulder of the wellhead (or housing) to support the slip bowl for the slip hanger or packoff to be used with the oil and gas equipment.

The system 114; 124 may be coupled together with threaded fasteners, including screws, bolts, studs, and nuts. These threaded fasteners (such as fastener 212) may be torqued to support energizing of an elastomer annular seal. An amount of the torque applied may cause material of the elastomer annular seal to deform radially. In at least one example, instead of the threaded fasteners, the top plate and a seal adjacent to the top plate may be associated together by an internal lockdown. The internal lockdown may include other types of screws, such as lock screws without the aligned stud holes. These lock screws may be associated with the wellhead 120, and provide a compressive force to the slip hanger compression plate.

FIG. 2 is a perspective view of aspects 200 of a slip hanger or a packoff subject to the anti-extrusion device, in accordance with at least one example. The anti-extrusion device is detailed further with respect to at least FIGS. 4A-6 herein. In at least one example, the system 114 herein is also referred to as seal assembly and the system 114; 124 is made up of a top plate 202 (also referred to also as a compression plate), a gland plate or seal elements 204, an elastomer annular seal 206, a further gland plate or seal elements 204, and a slip bowl 208 (or outer bowl). The slip hanger may include slip segments (in FIG. 4A), which may be between the slip bowl 208 and the tubular or casing 116. The slip segments may engage the tubular or casing 116. The slip bowl 208 may be provided in two or more bowl segments. Further, each of the slip segments and the bowl segments may be two semi-circular or 180 degree members, but may include more than two segments.

The bowl segments may be joined at a split 210, whereas the slip segments may be joined similarly at their respective segments and in a manner to not have any leak therethrough. A seal assembly and the system 114; 124 may generally be a slip hanger or packoff depending on its operations and usage in the oil and gas equipment 100. The elastomer annular seal 206 may occupy an annulus seal gland area, which may be formed by a slip bowl 208 and portions of the tubular or casing 116, a housing of a wellhead 120, and the top plate 202 that are annular around the slip bowl 208. As a result, a gland volume of the annulus seal gland, used herein, may be in reference to the space formed within the slip bowl 208 and portions of the tubular or casing 116, a housing of a wellhead 120, and the top plate 202 that are annularly around the slip bowl 208. FIG. 2 also illustrates that fasteners 212 at the top plate 202 may be used to hold and apply compression to one or more of the elastomer annular seal 206 or the gland plates or seal element 204.

In at least one example, the top plate 202 is for a slip hanger or a packoff and forms at least one part of a slip bowl 208 to retain an elastomer annular seal 206 with the slip bowl 208. In at least one example, the top plate 202 restrains the elastomer annular seal 206 in at least one direction. The top plate 202 is associated with the elastomer annular seal 206, a bottom gland plate or seal elements 204, which may be optional, and the slip bowl 208 under a fastener preload (such as from the fasteners 212). The association may be under thermal expansion, or under pressure load of the seal assembly and the system 114; 124. FIG. 2 illustrates that a tubular or casing 116 is provided through an axis 220 of the system of the slip hanger or packoff.

In at least one example, example materials for at least the top plate 202 and other plates to be used with the slip bowl 208 include inelastic or rigid materials, such as carbon steel or stainless steel, whereas the elastomer annular seal 206 may be of an elastomer material. In at least one example, such elastomer may include hydrogenated nitrile butadiene rubber (HNBR), nitrile butadiene rubber (NBR), or fluorocarbon rubber (such as FKM, FFKM and FEPM).

In at least one example, the bowl segments are axially fastened together from a top side of the top plate 202 using fasteners 212 that are threaded and that thread into a bolt hole, and through the elastomer annular seal 206 before reaching the slip bowl 208. Even though illustrated below the top plate 202, the elastomer annular seal 206 may be above the top plate 202, in at least one example. The fasteners 212 may be a hexagonal headed socket but may be any suitable lock screws or studs used to bring together the top plate 202 and the elastomer annular seal 206.

FIG. 3A is a perspective view of aspects 300 of a slip hanger or a packoff within a spool, in accordance with at least one example. As described with respect to FIG. 1, a system 114 for a slip hanger or a packoff may be used to perform operations associated with a tubular or casing 116 and may be located within a casing hanger spool 118. In at least one example, the system 114 of a slip hanger or a packoff herein may have bowl segments that may be provided with the slip segments. The top plate 202, the gland plates or seal elements 204, and the elastomer annular seal 206 may be in a landed position prior to being in an energized position (also referred to herein as an engaged position). In the energized position, one or more of the applied torque to the fasteners 212 or any further energizing or engaging action in the oil and gas equipment causes the anti-extrusion device to deform radially and to prevent extrusion of the elastomer annular seal 206 into the extrusion gaps between system 114 and tubular or casing 116. The operations associated with a tubular or casing 116 of the oil and gas equipment 100 may be performed in the energized position for the elastomer annular seal 206.

Further, the slip segments may include an outer profile that is textured (as illustrated in FIG. 4A), to interface with the tubular or casing 116. For example, the tubular or casing 116 asserts a downward load and, therefore, movement to the slip segments. The texture may be upward facing horizontal and circumferential grooves. These grooves allow gripping of the tubular or casing 116 and allow transfer of load from the tubular or casing 116 to the slip segments. The figures herein also illustrate that a slip hanger may be aligned with an axis 220 of a wellbore. Therefore, upward axial movement 252 herein, unless otherwise described, is aligned in parallel with the axis 220 of the wellbore and is outward with respect to the wellbore, whereas downward axial movement 254 herein, unless otherwise described, is aligned in parallel with the axis 220 of the wellbore and is inward with respect to the wellbore. The axial movements are described further with other figures herein but may be caused by installation, preloading, loading, and retrieval of one or more of the tubular or casing 116, the slip segments, or the slip bowl 208. In one example, the slip segments may be supported by the slip bowl 208 herein.

FIG. 3B is a cross-sectional perspective view of aspects 350 of a slip hanger or a packoff within a spool, in accordance with at least one example. As described with respect to FIGS. 1 and 3A, a system 114 for a slip hanger or a packoff may be used to perform operations associated with a tubular or casing 116 and may be located within a casing hanger spool 118. FIG. 3B illustrates that multiple anti-extrusion devices 352, 354 may be used in the system 114 with the slip hanger or a packoff and between the casing hanger spool 118 and the tubular or casing 116. There may be internal-facing anti-extrusion devices 352 that may face the tubular or casing 116, and there may be external-facing anti-extrusion devices 354 that may face a casing hanger spool 118.

FIG. 4A is a side cross-section view of aspects 400 of a slip hanger or a packoff with the anti-extrusion device in a landed position (also in FIG. 4B), in accordance with at least one example. The aspects 400 may be a system for oil and gas equipment. The system may include one or more anti-extrusion devices 402, with each having an annular lattice structure 406 and an annular plate 404. The annular lattice structure 406 and an annular plate 404 may be integrated with the annular lattice structure 406.

Although gaps are illustrated in FIG. 4A, the illustration may be only for ease of recognition of the components of the anti-extrusion device 402 and integration, as used herein, unless otherwise stated. There may be extrusion gaps 436 (in FIG. 4C) in the oil and gas equipment that allow the anti-extrusion device 402 to fill therein or to reduce a dimension thereof, upon deformation. The filling of the extrusion gaps 436 may occur entirely, unless otherwise specified herein. Similarly, the gaps throughout the aspects 400 are illustrative only as to the different components, but it is appreciated that there is sealing in the aspects 400 so that the extrusion gaps are specifically reduced in dimension or are not present, unless otherwise specified herein.

The anti-extrusion device 402 may be used with an elastomer annular seal 206 in an application of the oil and gas equipment. The elastomer annular seal 206 and the anti-extrusion device 402 are energized together by the fasteners 212 providing loads 434 (in FIG. 4C). The annular lattice structure 406 may be radially moved and deformed 432 (also in FIG. 4C), along with the annular plates 404 that can also deform in a similar manner. The annular lattice structure 406, including its structural elements, provides voids (such as in FIG. 5A) that may be filled with material (such as an elastomer). The filled voids are able to deform to fill or to reduce a size or dimension of the extrusion gaps 436 and are able to prevent extrusion from the elastomer annular seal 206. In one example, the material in the voids may be an elastomer provided during a manufacturing process for the anti-extrusion device 402. In another example, the manufacturing process for the anti-extrusion device 402 includes manufacturing of the elastomer annular seal 206, at the same time or together with the anti-extrusion device. As such, the elastomer annular seal 206 may include the same elastomer that is used to fill the voids in the annular lattice structure. This elastomer may be similar or a variation of the elastomer used for the elastomer annular seal 206.

FIG. 4B illustrates details 420 of anti-extrusion devices in a landed position, in accordance with at least one example. In the details 420, there are multiple anti-extrusion devices 402 in the landed position that may face a housing 410 on one side and that may face the casing 116 on the other side. Similar to the discussion with respect to FIG. 4A, each of the anti-extrusion devices 402 may include an annular lattice structure 406 and an annular plate 404 (only marked on one of the anti-extrusion devices illustrated, but may be provided on the anti-extrusion devices illustrated). The annular lattice structure 406 and an annular plate 404 may be integrated with the annular lattice structure 406. There may be extrusion gaps 436 (as in FIG. 4C) in the oil and gas equipment that allow the anti-extrusion device 402 to fill therein or to reduce a dimension thereof, upon deformation.

FIG. 4C illustrates details 430 of loads, deformation, and movement in all or part of the anti-extrusion device in an energized or engaged position, in accordance with at least one example. The energized or engaged position may be based in part on the top plate 202, the gland plates or seal elements 204, and the elastomer annular seal 206 being energized. The energized or engaged position is illustrated by a radial movement or deformation 432 of one or more of the annular lattice structure 406 or the annular plate 404, relative to the landed position (illustrated in at least FIGS. 4A-4B) for at least the anti-extrusion device 402.

In one example, an original shape of the annular lattice structure 406 may be deformed radially along the radial movement or deformation 432 illustrated. The annular plates 404 may also deform in a similar radial manner or may maintain (or substantially maintain its shape), at least relative to the annular lattice structure 406. In addition, one or more of the annular lattice structure 406 or the annular plate 404 may expand radially (such as by being part of the radial movement or deformation 432), resulting in an energized position for the elastomer annular seal 206 and the anti-extrusion device 402. FIG. 4C also illustrates that the annular lattice structures 406, having structural elements with filled voids (as detailed in FIGS. 5A-5D, for instance), may predictably allow reduction to larger extrusion gaps 436 and may support loads 434 from the fasteners 212 with minimal setting loads than otherwise possible.

The annular lattice structure 406 and the annular plate 404 may be printed or formed together (or manufactured) as part of the integration. In an example, a second anti-extrusion device, when used as part of multiple anti-extrusion devices (in the systems of FIGS. 4A-4C), may be located opposite to a first anti-extrusion device. For instance, there may be a top anti-extrusion device 402 and a bottom anti-extrusion device 402, relative to an axis 220 of the wellbore. There may be internal-facing anti-extrusion devices (352 in FIG. 3B) that may face the casing 116 and may be external-facing anti-extrusion devices 354 that may face a casing hanger spool 118 or a housing 410. A top anti-extrusion device 402 may be above the elastomer annular seal 206 with the elastomer annular seal positioned vertically along the axis 220 of the wellbore. A bottom anti-extrusion device 402 may be below the elastomer annular seal 206.

FIG. 4D is a detailed side cross-section view of aspects 450 of an elastomer annular seal with an anti-extrusion device in a landed position, in accordance with at least one example. FIG. 4B illustrates multiple variations of the anti-extrusion device within a same application, but it is readily apparent that there may be a singular type for all the anti-extrusion devices used in a single application. For example, in one variation, the aspects 400, including the illustrated system, may be such that an annular plate 404 may extend beyond an end surface 452 of the annular lattice structure 406 and may be above or below a leg feature 456 of the elastomer annular seal 206. In another example, FIG. 4B illustrates that the annular plate 404 may be a segmented annular plate 454 having segments that neighbor each other on a same horizontal axis that is perpendicular to the axis 220 of the wellbore. This is at least relative to the annular plate 404 in FIG. 4A that may be a singular annular structure or that may have two half-members, for instance.

FIG. 4E is a detailed perspective view of aspects 470 of an elastomer annular seal with an anti-extrusion device, in accordance with at least one example. In one example, the aspects 470 include the anti-extrusion device 402 having two different annular plates, a segmented annular plate 454 used together with a solid annular plate 480. In another example, the same type of annular plates may be used in a single application. The segments in a segmented annular plate 454 may reduce a load required to energize the elastomer annular seal as the separations between segments allow relative movement, in one example.

In another example, the aspects 470, including the illustrated system, may be such that an annular plate 404 may include at least two layers of segments to form a layered annular plate 472. There are two callouts illustrating different examples of the layered annular plate 472. In one example, the layered annular plate 472 may or may not have segments. In another example, when the layered annular plate 472 has segments, there may be segment gaps 476 to allow an interface, into the segment gaps, with the annular lattice structure. The layered annular plate 472 may or may not have a layer gap 474 between the layers. In the layered annular plate 472, at least two layers may be stacked vertically along an axis 220 of the wellbore. The aspects 400, including the illustrated system, may be such that there are apertures 478 through at least the elastomer annular seal 206 to allow the fasteners 212 to be provided through the elastomer annular seal 206.

FIG. 5A illustrates general and specific views 500 of an annular lattice structure having structural elements in the format of an array of cells having voids that are filled voids, in accordance with at least one example. A general view 502 illustrates that the annular lattice structure 406 has an array of cells 506, which form the structural elements, which are repeatable and uniform, and which include voids 510. A specific view 504 illustrates that the array of cells 506 includes the voids 510 that may be filled with elastomer to provide filled voids 508. The filled voids 508 of the array of cells 506 may include the material provided as part of a manufacturing process for the annular lattice structure 406. In one example, the material in the filled voids 508 allows energizing of the annular lattice structure and of the annular plate, so that they become radially deformed and so that they may prevent extrusion 438 from the elastomer annular seal 206, in a direction parallel to the axis of the wellbore.

FIG. 5B illustrates different formats 550 for structural elements of the annular lattice structure, relative to FIG. 5A, in accordance with at least one example. The annular lattice structure 406 may include a lattice format 552, 554 with side cross supports. The annular lattice structure 406 may include a lattice format 556, 558 with only bottom and diagonal supports. The annular lattice structure 406 may include an octahedral lattice format 560. The annular lattice structure 406 may include a substantially uniform lattice format 562 or a diamond lattice format 564, which may be extrapolations or variations of the octahedral lattice format 560. Each of the different formats 550 are individually repeatable patterns of uniform lattice formats.

When the elastomer annular seal is energized, the annular lattice structure 406 may automatically deform. The deforming of the annular lattice structure 406 may be so that the array of cells 506 of the annular lattice structure 406 and filled voids 508 therebetween may be reduced in size or closed. This deformation also reduces the size of any extrusion gaps or closes any extrusion gaps between the elastomer annular seal and the casing. The energizing of the anti-extrusion device may force one or more of the annular plate 404 or the annular lattice structure to deform from the elastomer annular seal 206 and to also move radially towards a casing 116.

FIG. 5C illustrates a further format 580 of structural elements used to form an annular lattice structure, in accordance with at least one example. The structural elements are represented by bristles 582. The bristles may be of graduated sizes or densities in first rows 584A, second rows 584B, third rows 584C, fourth rows 584D, and so on. Even with the graduated sizes or densities, one or more of such rows 584A-584D may represent a repeatable pattern 586 of bristles format or an individually repeatable pattern of uniform lattice formats. The gaps between the structural elements represent voids 588 that may be filled with elastomer. The orientation of the bristles format of the anti-extrusion device may be dependent on its application.

FIG. 5D illustrates further formats 590 of structural elements used to form an annular lattice structure, in accordance with at least one example. FIG. 5D illustrates a first lattice format of a repeatable pattern 586, in a 2-dimensional view, with graduated sizes or densities in 2 dimensions; and illustrates a second lattice format of a repeatable pattern 586, in a 3-dimensional view, with graduated sizes or densities in 3 dimensions. All such repeatable patterns 586 may include voids that may be filled voids using an elastomer in a manufacturing process before being in a landed position and an energized position in an oil and gas equipment.

In one example, an anti-extrusion device may only include an annular lattice structure, such as illustrated in FIGS. 5C and 5D. Beams associated with the annular lattice structure may increase in diameter at one end of the annular lattice structure, relative to another end, as illustrated. While the thicker dimensions may interfere with deformation of the annular lattice structure in response to energization, it may allow an effective arrest of extrusion at a lower pressure while also allowing elimination of an annular plate. In one example, use of an annular lattice structure alone may allow increased beam diameters at an end that is away from the elastomer annular seal. In another example, the annular plate, when used with the annular lattice structure, may also include a lattice geometry as in the case of the annular lattice structure but the lattice geometry may be more dense relative to the annular lattice structure.

FIG. 6 is a flow diagram of a method for a system of a slip hanger or a packoff having an anti-extrusion device with an annular lattice structure and an annular plate integrated with the annular lattice structure, described at least in FIGS. 1-5D herein, in accordance with at least one example. The method 600 is for a slip hanger or a packoff to be used with an oil and gas equipment. The method 600 may include a step to determine 602 an application in the oil and gas equipment which has an elastomer annular seal. The method 600 may include a step to form 604 an anti-extrusion device for the application. The anti-extrusion device may be formed with an annular plate integrated with the annular lattice structure. The method 600 may include a step to energize 606 the elastomer annular seal within the oil and gas equipment to cause, in part, one or more of the annular lattice structure or the annular plate to deform to prevent the elastomer annular seal from extruding into extrusion gaps in the oil and gas equipment. In one example, the deformation may reduce dimensions of the extrusion gaps or may close the extrusion gaps.

The method 600 may be such that the forming of the annular lattice structure includes a further step or a sub-step for manufacturing the annular plate together with the annular lattice structure. Dimensions or configurations of one or more of the annular lattice structure or the annular plate may be based at least in part on one or more of the application. Further, the dimensions or configurations of one or more of the annular lattice structure or the annular plate may be also or independently based in part on dimensions of the elastomer annular seal, or dimensions of at least one component within the oil and gas equipment, such as spacing within the oil and gas application.

The method 600 may be such that the forming of the anti-extrusion device with the annular plate may allow the annular plate to extend beyond an end surface of the annular lattice structure and to be above or below a leg feature of the elastomer annular seal. The method 600 may include forming a second anti-extrusion device and locating the second anti-extrusion device opposite to the anti-extrusion device for the application. The anti-extrusion device may be located above the elastomer annular seal, with the elastomer annular seal positioned vertically along an axis of a wellbore. The second anti-extrusion device may be located below the elastomer annular seal.

The method 600 may be such that the annular lattice structure may be formed to include an array of cells or other structural elements with filled voids therebetween. The method 600 may be the annular lattice structure having an array of cells or other structural elements with voids therebetween. The method 600 may include a manufacturing process of filling the voids with an elastomer to provide the filled voids in the manufacturing process for the annular lattice structure.

The method 600 may be such that the annular lattice structure includes an array of cells in a lattice format with side cross supports. Another lattice format may have only bottom and diagonal supports. In another example, the annular lattice structure includes an octahedral lattice format. In another example, the annular lattice structure includes a substantially uniform lattice format. In another example, the annular lattice structure includes a gradient lattice format, a bristles format, a repeating lattice format, or a diamond lattice format. The method 600 may include a step or sub-step for allowing the deformation of one or more of the annular plate or the annular lattice structure so that extrusion gaps in the system of the oil and gas equipment are reduced in size.

While techniques herein may be subject to modifications and alternative constructions, these variations are within the spirit of present disclosure. As such, certain illustrated examples are shown in drawings and have been described above in detail, but these are not limiting disclosure to specific form or forms disclosed; instead, cover all modifications, alternative constructions, and equivalents falling within the spirit and scope of disclosure, as defined in appended claims.

When introducing elements of various examples of the present invention, the articles “a,” “an,” “the,” and “said” are intended to mean that there are one or more of the elements. The terms “comprising,” “including,” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements. Any examples of operating parameters and/or environmental conditions are not exclusive of other parameters/conditions of the disclosed examples. Additionally, it should be understood that references to “one example”, “an example”, “certain examples,” or “other examples” of the present invention are not intended to be interpreted as excluding the existence of additional examples that also incorporate the recited features. Furthermore, reference to terms such as “above,” “below,” “upper”, “lower”, “side”, “front,” “back,” or other terms regarding orientation are made with reference to the illustrated examples and are not intended to be limiting or exclude other orientations.

Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within range, unless otherwise indicated herein and each separate value is incorporated into specification as if it were individually recited herein. In at least one example, use of a term, such as a set (for a set of items) or subset unless otherwise noted or contradicted by context, is understood to be nonempty collection including one or more members. Further, unless otherwise noted or contradicted by context, term subset of a corresponding set does not necessarily denote a proper subset of corresponding set, but subset and corresponding set may be equal.

Conjunctive language, such as phrases of form, at least one of A, B, and C, or at least one of A, B and C, unless specifically stated otherwise or otherwise clearly contradicted by context, is otherwise understood with context as used in general to present that an item, term, etc., may be either A or B or C, or any nonempty subset of set of A and B and C. In at least one example of a set having three members, conjunctive phrases, such as at least one of A, B, and C and at least one of A, B and C refer to any of following sets: {A}, {B}, {C}, {A, B}, {A, C}, {B, C}, {A, B, C}. Thus, such conjunctive language is not generally intended to imply that certain examples require at least one of A, at least one of B and at least one of C each to be present. In addition, unless otherwise noted or contradicted by context, terms such as plurality indicate a state of being plural (such as a plurality of items indicates multiple items). In at least one example, a number of items in a plurality is at least two but can be more when so indicated either explicitly or by context. Further, unless stated otherwise or otherwise clear from context, phrases such as based on means based at least in part on and not based solely on.

In at least one example, even though the above discussion provides at least one example having implementations of described techniques, other architectures may be used to implement described functionality, and are intended to be within the scope of this disclosure. In addition, although specific responsibilities may be distributed to components and processes, they are defined above for purposes of discussion, and various functions and responsibilities might be distributed and divided in different ways, depending on circumstances.

In at least one example, although subject matter has been described in language specific to structures and/or methods or processes, it is to be understood that subject matter claimed in appended claims is not limited to specific structures or methods described. Instead, specific structures or methods are disclosed as example forms of how a claim may be implemented.

From all the above, a person of ordinary skill would readily understand that the tool of the present disclosure provides numerous technical and commercial advantages and can be used in a variety of applications. Various examples may be combined or modified based in part on the present disclosure, which is readily understood to support such combination and modifications to achieve the benefits described above.

It should be appreciated that examples herein may utilize one or more values that may be experimentally determined or correlated to certain performance characteristics based on operating conditions under similar or different conditions. The present disclosure described herein, therefore, is well adapted to carry out the objects and attain the ends and advantages mentioned, as well as others inherent therein. While a presently preferred example of the disclosure has been given for purposes of disclosure, numerous changes exist in the details of procedures for accomplishing the desired results. These and other similar modifications will readily suggest themselves to those skilled in the art and are intended to be encompassed within the spirit of the present disclosure disclosed herein and the scope of the appended claims.

Claims

1. A wellhead system comprising a slip hanger, wherein the slip hanger comprises:

a slip bowl;

a top plate;

an elastomer annular seal configured to be disposed axially between the slip bowl and the top plate;

an anti-extrusion device comprising: an annular plate configured to be positioned toward the slip bowl or positioned toward the top plate; and an annular lattice structure configured to be disposed axially between the elastomer annular seal and the annular plate, wherein the anti-extrusion device is configured to be deformed when the elastomer annular seal is energized to facilitate blocking the elastomer annular seal from extruding into adjacent-extrusion gaps in the wellhead system;

a fastener configured to secure the top plate and the elastomer annular seal to the slip bowl such that the fastener is configured to be tightened to axially compress the elastomer annular seal between the top plate and the slip bowl to energize the elastomer annular seal; and

a gland plate configured to be disposed axially between the top plate and the elastomer annular seal or axially between the elastomer annular seal and the slip bowl such that the fastener extends axially therethrough, wherein the fastener is configured to be tightened to compress the gland plate directly against the elastomer annular seal and the annular plate of the anti-extrusion device.

2. The wellhead system of claim 1, wherein the annular lattice structure and the annular plate of the anti-extrusion device are integrated together to form a unitary structure.

3. The wellhead system of claim 1, wherein:

the elastomer annular seal comprises a leg feature; and

the annular plate is configured to extend radially beyond an end surface of the annular lattice structure and axially overlap with the leg feature of the elastomer annular seal.

4. The wellhead system of claim 1, wherein:

the annular plate of the anti-extrusion device is configured to be positioned toward the top plate; and

the slip hanger further comprises another anti-extrusion device, wherein the another anti-extrusion device comprises: another annular plate configured to be positioned toward the slip bowl; and another annular lattice structure configured to be disposed axially between the elastomer annular seal and the another annular plate, wherein the another anti-extrusion device is configured to be deformed when the elastomer annular seal is energized to block the elastomer annular seal from extruding into other adjacent extrusion gaps in the wellhead system.

5. The wellhead system of claim 1, wherein the annular lattice structure comprises voids filled with elastomer.

6.-22. (canceled)

23. The wellhead system of claim 1, wherein the annular lattice structure of the anti-extrusion device comprises a three-dimensional array of cellular voids.

24.-25. (canceled)

26. A system for oil and gas equipment, comprising:

an anti-extrusion device comprising an annular lattice structure; and

an annular plate integrated with the annular lattice structure, wherein the anti-extrusion device is used with an elastomer annular seal and wherein, when the elastomer annular seal is energized, one or more of the annular lattice structure or the annular plate is to deform and is to prevent the elastomer annular seal from extruding into extrusion gaps of the oil and gas equipment, wherein the annular plate comprises segments to reduce a load required to energize the elastomer annular seal.

27. The system for oil and gas equipment of claim 26, wherein the annular lattice structure comprises a three-dimensional array of cellular voids.

28.-29. (canceled)

30. A wellhead system comprising a slip hanger, wherein the slip hanger comprises:

a slip bowl;

a top plate;

an elastomer annular seal configured to be disposed axially between the slip bowl and the top plate; and

an anti-extrusion device configured to be positioned along an outer circumference of the elastomer annular seal, wherein the anti-extrusion device comprises: an annular plate configured to be positioned toward the slip bowl or positioned toward the top plate; and an annular lattice structure configured to be disposed axially between the elastomer annular seal and the annular plate, wherein the anti-extrusion device is configured to be deformed when the elastomer annular seal is energized to facilitate blocking the elastomer annular seal from extruding into adjacent-extrusion gaps in the wellhead system; and

another anti-extrusion device configured to be positioned along an inner circumference of the elastomer annular seal, wherein the another anti-extrusion device comprises: another annular plate configured to be positioned toward the top plate or the slip bowl; and another annular lattice structure configured to be disposed axially between the elastomer annular seal and the another annular plate, wherein the another anti-extrusion device is configured to be deformed when the elastomer annular seal is energized to block the elastomer annular seal from extruding into other adjacent extrusion gaps in the wellhead system.

31. The wellhead system of claim 30, wherein the annular lattice structure and the annular plate of the anti-extrusion device are integrated together to form a unitary structure.

32. The wellhead system of claim 30, wherein the annular lattice structure comprises a three-dimensional array of cellular voids.

33. The wellhead system of claim 30, wherein the annular lattice structure comprises voids filled with elastomer.

34. The wellhead system of claim 30, wherein:

the elastomer annular seal comprises a leg feature; and

the annular plate is configured to extend radially beyond an end surface of the annular lattice structure and axially overlap with the leg feature of the elastomer annular seal.

35. The wellhead of claim 30, wherein the annular lattice structure comprises side cross supports, bottom supports, diagonal supports, an octahedral lattice structure, a diamond lattice structure, bristles, or any combination thereof.

36. A wellhead system comprising a slip hanger, wherein the slip hanger comprises:

a slip bowl;

a top plate;

an elastomer annular seal configured to be disposed axially between the slip bowl and the top plate; and

an anti-extrusion device comprising: an annular plate configured to be positioned toward the slip bowl or positioned toward the top plate; and an annular lattice structure configured to be disposed axially between the elastomer annular seal and the annular plate, wherein: the anti-extrusion device is configured to be deformed when the elastomer annular seal is energized to facilitate blocking the elastomer annular seal from extruding into adjacent-extrusion gaps in the wellhead system; and the anti-extrusion device is configured to be disposed within a notch in the elastomer annular seal that is formed: along an upper end of an outer circumference of the elastomer annular seal; along another upper end of an inner circumference of the elastomer annular seal; along a lower end of the outer circumference of the elastomer annular seal; or along another lower end of the inner circumference of the elastomer annular seal.

37. The wellhead system of claim 36, wherein the annular lattice structure and the annular plate of the anti-extrusion device are integrated together to form a unitary structure.

38. The wellhead system of claim 36, wherein the annular lattice structure comprises a three-dimensional array of cellular voids.

39. The wellhead system of claim 36, wherein the annular lattice structure comprises voids filled with elastomer.

40. The wellhead system of claim 36, wherein:

the elastomer annular seal comprises a leg feature; and

the annular plate is configured to extend radially beyond an end surface of the annular lattice structure and axially overlap with the leg feature of the elastomer annular seal.

41. The wellhead system of claim 36, wherein the annular lattice structure comprises side cross supports, bottom supports, diagonal supports, an octahedral lattice structure, a diamond lattice structure, bristles, or any combination thereof.

42. The wellhead system of claim 36, wherein:

the annular plate of the anti-extrusion device is configured to be positioned toward the top plate; and

the slip hanger further comprises another anti-extrusion device, wherein the another anti-extrusion device comprises: another annular plate configured to be positioned toward the slip bowl; and another annular lattice structure configured to be disposed axially between the elastomer annular seal and the another annular plate, wherein the another anti-extrusion device is configured to be deformed when the elastomer annular seal is energized to block the elastomer annular seal from extruding into other adjacent extrusion gaps in the wellhead system.