Patent Application
20240309716
This disclosure relates generally to oilfield equipment and more particularly to systems and methods for a compliant compression plate for a slip hanger or a packoff.
A slip hanger, such as a manual slip hanger, is a type of wellhead equipment used with oilfield equipment to support the weight of oilfield tubulars 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 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 oilfield equipment to prevent fluid leakage between sections of the equipment, such as to isolate the annulus volume from a bore volume in a wellhead. There may be many different components associated with the slip hanger or the packoff to enable their functioning.
In at least one embodiment, a system for a slip hanger or a packoff to be used with oilfield equipment includes a compression plate having one or more grooves or slots extending circumferentially with respect to an axis of the slip hanger or the packoff. The compression plate is to be associated with an annulus seal gland of the slip hanger or the packoff and is to enable a gland volume of the annulus seal gland to change with temperature applied to the slip hanger or the packoff.
In at least one embodiment, a compression plate to be used with a slip hanger or a packoff in oilfield equipment is disclosed. The compression plate has one or more grooves or slots extending circumferentially with respect to an axis of the slip hanger or the packoff. The compression plate is to be associated with an annulus seal gland of the slip hanger or the packoff and is to enable a gland volume of the annulus seal gland to change with temperature applied to the slip hanger or the packoff.
In at least one embodiment, a method for using a slip hanger or a packoff in an oilfield equipment includes determining a load or temperature to be applied to the slip hanger or the packoff. The method includes enabling a compression plate to be associated with an annulus seal gland of the slip hanger or the packoff. The compression plate includes one or more grooves or slots extending circumferentially with respect to an axis of the slip hanger or the packoff. The one or more grooves or slots is to enable a gland volume of the annulus seal gland to change with temperature applied to the slip hanger or the packoff.
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:
While the disclosure will be described in connection with the preferred embodiments, it will be understood that it is not intended to limit the disclosure to that embodiment. 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.
The foregoing aspects, features and advantages of the present technology will be further appreciated when considered with reference to the following description of preferred embodiments and accompanying drawings, wherein like reference numerals represent like elements. In describing the preferred embodiments 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 embodiment, to resolve issues described above, a compliant compression plate can be used with a slip hanger or a packoff in oilfield equipment. The compression plate is complaint because, in part, it includes one or more grooves or slots that extend circumferentially with respect to an axis of the slip hanger or the packoff. The compression plate can enable a preload to an annulus seal gland associated with the slip hanger or the packoff and can enable a gland volume of the annulus seal gland to change with temperature applied to the slip hanger or the packoff.
In at least one embodiment, a slip hanger or packoff may be used with a compression seal and may include an integral compliant section. The compliant section may include the compression plate and may be replaceable to provide a different spring stiffness to a seal system or a packoff, which also accommodates thermal effects depending on the application. The compliant section may be a series of machined features, such as the above referenced grooves or slots to the compression plate. Further, within a compression plate, the grooves or slots may be non-uniform, such as a different widths, heights, depths, and other geometric variations to provide different configurations. In at least one embodiment, there may be compression plates that have uniform grooves or slots.
In at least one embodiment, the machined features are grooved or slots that provide a predetermined stiffness to the seal system including a packoff or to a slip hanger. The compliant section can deform at a predetermined spring rate under loads, such as thermal loads, from an expanding and contracting seal. The deforming of the compliant section allows a preload to an annulus seal gland associated with the slip hanger or the packoff and can enable a gland volume of the annulus seal gland to change with temperature applied to the slip hanger or the packoff. In at least one embodiment, the annulus seal gland is formed, in part, with inclusion of a slip bowl or a packoff body.
In at least one embodiment, therefore, a purpose of the compliant section is to accommodate for thermal expansion of a compression seal, which may include an elastomer seal, at high temperature. A further purpose of the compliant section is to provide compression force to a contracted seal at low temperature. The compliance of the compression plate is enabled across an engineered deflection range through the machined feature and functionally addresses the issues of a rigid gland, bowl, or body of a slip hanger or packoff.
In at least one embodiment, the machined features provide a compliant geometrical configuration that is integral to the compression plate. This geometrical configuration may be an arrangement of milled slots extending circumferentially with respect to an axis of the slip hanger or the packoff. Alternatively, the geometrical configuration may be a set of grooves that are continuous around a circumference of the compression plate, which make them radial grooves.
In at least one embodiment, the grooves include one or more of first grooves that extend from an inner surface and partly towards an outer surface of the compression plate or second grooves that extend from an outer surface and partly towards an inner surface of the compression plate. When a compression plate includes one of a first groove and one of a second groove, the compression plate will have a serpentine cross-section. In at least one embodiment, when the geometrical configuration is slots extending from an inner surface, the slots are fully through an outer surface of the compression plate, unlike the first grooves, for instance.
The compression plate having the one or more of the grooves or slots can address issues in elastomer seals that undergo thermal expansion and/or contraction in a rigid gland, bowl, or body of a slip hanger or packoff. Instead of such rigidity, a complaint section of the grooves or slots, in the compression plate, flexes under load and accepts a preload as well as change in an annulus seal volume of an annulus seal gland of a slip hanger or packoff. As the compression seal contracts, the compliant section provides a compressive force on a compression seal, to accommodate for a reduction in a seal volume of the compression seal. As the compression seal expands, the compliant section flexes to accommodate for the increase in volume. These properties in the compliant section minimize the chances of extrusion at high temperature and minimize the loss of sealing contact pressure of the seal at low temperature. In at least one embodiment, further to the benefits described, there are fewer parts in using the compression plate herein, such as an absence of individual spring plates, spring washers, and other such features.
Further, as illustrated in
In at least one embodiment, a system 114 of a slip hanger having a compression plate with grooves or slots may be used to perform operations associated with a tubing string 116 and may be located within a casing hanger spool 118. In at least one embodiment, further, a system 124 of a slip hanger having a compression plate with grooves or slots may be used to perform operations associated with a tubing string 116 and may be located within a tubing head 110 of the oilfield equipment 100.
In at least one embodiment, a system of a slip hanger having a compression plate with grooves or slots 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 tubing string 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 a slip hanger having a compression plate with grooves or slots.
In at least one embodiment, a casing string may line walls of a wellbore and may be supported by a slip hanger 114 mounted to a wellhead 120, but associations to one or more of a casing hanger spool 118 or another feature. The slip hanger may be referred to also as a casing hanger. In at least one embodiment, wedge-shaped segmented slips may be provided for coupling between the slip hanger 114 and the tubing string 116. Further, compression seal assemblies may be provided for preventing pressure communication and may be provided between the tubing string 116 and wellhead 120.
In at least one embodiment, a system of a slip hanger 114 or a system of a packoff 124 may include a compression plate having machined features that, along with the compression seal, allow change in shape and volume for an annulus seal gland that includes a slip bowl or a packoff body under load that causes thermal effects to apply to the slip hanger or the packoff. The system 114 may be coupled together with threaded fasteners, including screws, bolts, studs, and nuts. These threaded fasteners may be torqued to an amount that causes the compression plate with grooves or slots to axially compress to provide a compressive preload force to the compression seal, to isolate the annulus between the tubing string 116 and wellhead 120. In at least one embodiment, instead of the threaded fasteners, the compression plate and the compression seal adjacent to the compression 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.
In at least one embodiment, the compression plate 202 is for a slip hanger or a packoff and forms at least one part of a slip bowl 208. In at least one embodiment, the compression plate 202 restrains the compression seal 206 in at least one direction. The compression plate 202 being of a predetermined stiffness, may be optimized based in part on an application of the slip hanger or a packoff. Such optimization may be based in part on factors associated with the application, including an operating temperature, a thermal expansion coefficient, a fastener preload, among other factors that are readily apparent to a skilled artisan reviewing the present disclosure.
The compliant section of the slotted compression plate 202 includes the slots 204 on the compliant plate that can flex axially relative to a wellbore 122 and can effectively compress under a fastener preload (such as from the fasteners 214) or under thermal expansion of the seal assembly and the system 114; 124. In at least one embodiment, the compliant section includes the slots 204 that may be axially separated from a top section and a bottom section that are solid materials (not slotted). This is further illustrated in a section view in
In at least one embodiment, the axial separation between the rows may be less than an axial separation from a row of slots 204 till a top or a bottom of the compression plate 202. In this manner, a section having the slots 204 is apparent relative to another section not having slots on the compression plate 202. The section having the slots 204 may be the compliant section of the compression plate 202. The slots 204 may be of different geometry, when non-uniform slots 204 are used. The compression seal 206 may be in a compressed state. As the elastomer of the compression seal 206 contracts under cold temperatures and in application, a volume of an annulus seal gland changes (a volume formed by the slip bowl 208 and portions of a tubular 116, a wellhead housing 120, and the compression plate 202 that are around the slip bowl 208, as readily appreciated by a skilled artisan). Such a change may cause a volume of the annulus seal gland to shrink to maintain the same pressure as initially intended.
In at least one embodiment, a change in the gland volume enables one or more of features associated with the annulus seal gland. The change enables a preload, in the annulus seal gland, to be maintained at a first temperature in which a compression seal that is associated with the slip hanger or the packoff contracts. The change enables an expansion of the compression seal without extrusion at a second predetermined temperature in which the compression seal expands. Further, the first temperature is a low temperature relative to the second temperature which may be many times higher than the first temperature.
In at least one embodiment, the compression seal 206 may be also bisectional having semi-circular members, along the sections 202A, 202B, joined together along a split 212 that may be offset from the split 210 for the compression plate 202. Further, in at least one embodiment, the compression plate 202 has two segments of machined features and may be joined at the split 210 but may have multiple segments instead. Example materials for at least the compression plate 202 include elastic materials, such as carbon steel or stainless steel, whereas the compression seal 206 may be of an elastomer material. In at least one embodiment, such elastomer may include hydrogenated nitrile butadiene rubber (HNBR) or Polyether ether ketone (PEEK). In at least one embodiment, the compression plate 202 can help to achieve a good seal at a low temperature. This is at least because a strain energy stored in the compression plate 202, at an ambient temperature, may be released at the low temperature to compensate for thermal contraction of the elastomer material.
In at least one embodiment, the sections are axially fastened together from a top side of the compression plate 202 using fasteners 214 that are threaded and that thread into a bolt hole, and through the compression seal 206 before reaching the slip bowl 208. Even though illustrated below the compression plate 202, the compression seal 206 may be above the compression plate 202, in at least one embodiment. The fasteners 214 may be hexagonal headed socket but may be any suitable lock screws or studs used to bring together the compression plate 202 and the compression seal 206.
In at least one embodiment, the compression plate 252 is for a slip hanger or a packoff and forms at least one part of a slip bowl 208. In at least one embodiment, the compression plate 252 restrains the compression seal 206 in at least one direction. The compression plate 252 may be being of a predetermined stiffness, which may be optimized based in part on an application of the slip hanger or a packoff. Like in the case of the slotted compression plate 202, such optimization may be based in part on factors associated with the application, including an operating temperature, a thermal expansion coefficient, a fastener preload, among other factors that are readily apparent to a skilled artisan reviewing the present disclosure.
The compliant section includes the grooves 254 on the compliant plate 202 that can flex axially relative to a wellbore 122 and can effectively compress under a fastener preload (such as from the fasteners 214) or under thermal expansion of the seal assembly and the system 114; 124. In at least one embodiment, the compliant section includes the groove 254 that may be axially separated from a top section and a bottom section that are solid materials (not grooved). This is further illustrated in a section view in
In at least one embodiment, each of the grooves 254 may extend fully around a circumference of the compression plate 252, unlike the slots 204, and may also not extend fully from an inner diameter (inner surface) to an outer diameter (outer surface) of the compression plate 252. Instead, the grooves 252 include one or more grooves, including first grooves (such as, on top) that extend from an inner surface and partly towards an outer surface of the compression plate 252 and/or second grooves (such as at the bottom from the first groove) that extend from an outer surface and partly towards an inner surface of the compression plate.
In at least one embodiment, the axial separation between the grooves 254 may be less than an axial separation from a groove 254 till a top or a bottom of the compression plate 252. In this manner, a section having the grooves 254 is apparent relative to another section not having such grooves 254 on the compression plate 252. The section having a groove 254 may be the compliant section of the compression plate 252. The grooves 254 may be of different width and height geometry (but extend fully around a circumference), when uniform or non-uniform grooves are used. The compression seal 206 may be in a compressed state. As the elastomer of the compression seal 206 contracts under cold, the volume of the annulus seal gland changes.
In at least one embodiment, like in the embodiment in
In at least one embodiment, the sections are axially fastened together from a top side of the compression plate 252 using fasteners 214 that are threaded and that thread into a bolt hole, and through the compression seal 206 before reaching the slip bowl 208. Even though illustrated below the compression plate 252, like in the embodiment in
In at least one embodiment,
In at least one embodiment,
In at least one embodiment, a system 114 of a slip hanger or a system 124 of a packoff to be used with oilfield equipment therefore includes a compression plate 202; 252 having one or more of grooves 254 or slots 204 extending circumferentially with respect to an axis 220 of the slip hanger or the packoff 114; 124. The compression plate 202, 252 can enable a preload to an annulus seal gland of an annulus seal associated with the slip hanger or the packoff 114; 124 and can enable a gland volume of the annulus seal gland to change with temperature applied to the slip hanger or the packoff 114; 124 under a load applied there to. For example, the load may be from the fasteners 214 being tightened prior to application in a wellhead or may be from supporting the weight of casing string in the wellhead, or from thermal contraction or expansion of a compression seal under thermal load.
In at least one embodiment, a compression seal 206 may be located adjacent to the compression plate 202; 252. The compression seal 206 may include an elastomer material. The system 114 of a slip hanger or the system 124 of a packoff may include a slip bowl, or packoff body that may be subject to change in volume. Further, the compression plate 202; 252 extends circumferentially in the slip hanger to accommodate multiple fasteners 214 and to associate the compression plate 202; 252 with the compression seal.
The system for a slip hanger (or separately, a packoff) may include the one or more of such compression plates 202; 252 having the one or more slots or groove 204, 254 can be interchangeable, where an application of one of the compression plates 202, 252 can be based in part a loading subject to in the slip hanger or the packoff. This allows for customization, such as to enable different heights, spans, numbers, or relative placement configuration of the compression plate 202; 252, to be adjustable to enable compliance and deflection that are customized in accordance with an application of the slip hanger.
The system for a slip hanger (or separately, a packoff) may be such that the compression plate 202; 252 enables resistance and stress differences. Further, the compression plate 202; 252 can enable compliance for the system 114; 124 under the load or a temperature applied to the slip hanger or packoff. In at least one embodiment, the system 114 for a slip hanger is such that the slots or grooves of the compression plate 202; 252 includes more than one row of slots or grooves.
The system for a slip hanger (or separately, a packoff) may be such that grooves 254 are continuous around a circumference of the compression plate 252. Further, the grooves 254 may include one or more of first grooves that extend from an inner surface and partly towards an outer surface of the compression plate 252 or second grooves that extend from an outer surface and partly towards an inner surface of the compression plate 252.
The system for a slip hanger (or separately, a packoff) may be such that individual ones of the slots 204 extend from an inner surface and fully through an outer surface of the compression plate 202. The system for a slip hanger (or separately, a packoff) may be such that the compression plate 202; 252 is interchangeable based in part on an application of the slip hanger 114 or the packoff 124.
The system for a slip hanger (or separately, a packoff) may be such that there may be replaceable compression plates that each include different geometric configurations of grooves or different configurations of slots. Further, individual ones of the compression plates can address different compliance and can be used to replace a compression plate depending on an application. For example, in an application of the slip hanger or the packoff, the compression plate is selectable to the application, with the individual ones of the compression plates being directed to different applications in a slip hanger or a packoff. In at least one embodiment, the slip hanger or packoff may be retrieved and the compression plate may be replaced with a same, similar, or different compression plate having grooves or slots according to a requirement presently in a wellbore.
In at least one embodiment, the method 600 includes providing (608) the compression plate to be associated with an annulus seal gland of the slip hanger or the packoff. The compression plate includes one or more of grooves or slots extending circumferentially with respect to an axis of the slip hanger or the packoff. The one or more of the grooves or slots enables (610) a gland volume of the annulus seal gland to change with temperature applied to the slip hanger or the packoff. Further, in step 610, the annulus seal gland is enabled to receive preload associated with the slip hanger or the packoff.
The method 650 includes determining or verifying (656) that the compression plate in step 654 is based on a load or a temperature of an application in which the slip hanger or packoff is to be used. The method 650 includes using fasteners to associate the compression plate with a compression seal and with a slip bowl or a packoff body. In at least one embodiment, method 600; 650 can include a further step or sub-step for providing a compression seal located adjacent to the compression plate and to be comprised of an elastomer material. In at least one embodiment, method 600; 650 can include a further step or sub-step for enabling the grooves of a compression plate to be continuous around a circumference of the compression plate. This may be part of the machining step 652 in method 650, for instance.
In at least one embodiment, method 600; 650 can include a further step or sub-step for enabling the plurality of grooves to include one or more of first grooves that extend from an inner surface and partly towards an outer surface of the compression plate or second grooves that extend from an outer surface and partly towards an inner surface of the compression plate. This may be also part of the machining step 652 in method 650, for instance. In at least one embodiment, method 600; 650 can include a further step or sub-step for enabling the individual ones of the slots to extend from an inner surface and fully through an outer surface of the compression plate.
While techniques herein may be subject to modifications and alternative constructions, these variations are within spirit of present disclosure. As such, certain illustrated embodiments are shown in drawings and have been described above in detail, but these are not limiting disclosure to specific form or forms disclosed; and instead, cover all modifications, alternative constructions, and equivalents falling within spirit and scope of disclosure, as defined in appended claims.
When introducing elements of various embodiments 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 embodiments. Additionally, it should be understood that references to “one embodiment”, “an embodiment”, “certain embodiments,” or “other embodiments” of the present invention are not intended to be interpreted as excluding the existence of additional embodiments 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 embodiments 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 embodiment, 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 embodiment 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 embodiments 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, indicates a state of being plural (such as, a plurality of items indicates multiple items). In at least one embodiment, 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 embodiment, even though the above discussion provides at least one embodiment having implementations of described techniques, other architectures may be used to implement described functionality, and are intended to be within 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 embodiment, 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 embodiments 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 embodiments 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 embodiment 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.
