Patent Application
20250020045
During wellbore operations, a liner may be “hung” onto a casing such that the liner supports an extended string of tubular below it. As used herein, “tubing string” refers to a series of connected pipe sections, casing sections, joints, screens, blanks, cross-over tools, downhole tools, and the like, inserted into a wellbore, whether used for drilling, work-over, production, injection, completion, or other processes. A tubing string may be run in and out of the casing, and similarly, tubing string can be run in an uncased wellbore or section of wellbore. Further, in many cases a tool may be run on a wireline or coiled tubing instead of a tubing string, as those of skill in the art will recognize.
Expandable liner hangers may generally be used to secure the liner within a previously set wellbore tubular (e.g., liner, casing or liner string). Expandable liner hangers may be “set” by expanding the liner hanger radially outward into gripping and sealing contact with the wellbore tubular. For example, expandable liner hangers may be expanded by use of hydraulic pressure to drive an expanding cone, wedge, or “pig,” through the liner hanger. Other methods may be used, such as mechanical swaging, explosive expansion, memory metal expansion, swellable material expansion, electromagnetic force-driven expansion, etc.
Embodiments of the disclosure may be better understood by referencing the accompanying drawings.
The description that follows includes example systems, methods, techniques, and program flows that embody aspects of the disclosure. However, it is understood that this disclosure may be practiced without these specific details. In some instances, well-known instruction instances, protocols, structures, and techniques have not been shown in detail in order not to obfuscate the description.
In the drawings and descriptions that follow, like parts are typically marked throughout the specification and drawings with the same reference numerals, respectively. The drawn figures are not necessarily to scale. Certain features of the disclosure may be shown exaggerated in scale or in somewhat schematic form and some details of certain elements may not be shown in the interest of clarity and conciseness. The present disclosure may be implemented in embodiments of different forms.
Specific embodiments are described in detail and are shown in the drawings, with the understanding that the present disclosure is to be considered an exemplification of the principles of the disclosure, and is not intended to limit the disclosure to that illustrated and described herein. It is to be fully recognized that the different teachings of the embodiments discussed herein may be employed separately or in any suitable combination to produce desired results.
Unless otherwise specified, use of the terms “connect.” “engage,” “couple.” “attach,” or any other like term describing an interaction between elements is not meant to limit the interaction to a direct interaction between the elements and may also include an indirect interaction between the elements described. Unless otherwise specified, use of the terms “up,” “upper.” “upward.” “uphole,” “upstream,” or other like terms shall be construed as generally away from the bottom, terminal end of a well; likewise, use of the terms “down,” “lower,” “downward,” “downhole,” or other like terms shall be construed as generally toward the bottom, terminal end of the well, regardless of the wellbore orientation. Use of any one or more of the foregoing terms shall not be construed as denoting positions along a perfectly vertical axis. In some instances, a part near the end of the well can be horizontal or even slightly directed upwards. Unless otherwise specified, use of the term “subterranean formation” shall be construed as encompassing both areas below exposed earth and areas below earth covered by water such as ocean or fresh water.
Expandable Liner Hangers (ELH) provide a robust and elegant design which has a strong record of success in the field for high pressure high temperature (HPHT) applications. Through plastic deformation of the hanger body, the metal spikes make firm contact with the casing inner diameter (ID) during the expansion process providing both anchoring and sealing capacity of the hanger. In many cases, a few short elastomer elements are added between the spikes to enhance the sealing performance to account for certain casings in downhole environments, such as, e.g., standard American Petroleum Institute (API) casings.
Current designs are facing challenges to seal the liner from extremely high annular pressure, especially for thick and high yield casing. The sealability of the metal spike is sensitive to dimension variation of the casing and the surface contact pressure between spikes and the casing is influenced by the maximum expansion force. More importantly, unlike most metal seal designs, the contact pressure between the spike and the casing ID will drop with the increase of annular pressure. The rubber elements, on the other hand, usually suffer from nibbling during expansion and the performance is considerably weakened under large temperature swings. In addition, the sour environment also limits choices for elastomers.
Several new concepts have been proposed to address these issues. Some seals which may be used rely on polymeric materials and or metal materials, which is not ideal for HPHT applications. The scalability of some spikes are limited by one or both of at the following two factors: 1) the inherent collapse strength of hanger body under combined load, which could lead to sudden opening of the clearance between a wellbore casing and hanger body outer diameter (OD); and 2) wear of the sealing surface under high compressive load.
Examples of an expandable liner hanger system and method disclosed herein include a standalone metal seal design for an ELH system to improve the sealing performance, and especially improve performance when there is pressure from below. In the examples provided herein, one feature of the liner hanger system includes a seal, such as a metal-to-metal (MTM) seal which can be energized annular pressure applied, i.e., the higher the applied annular pressure, the higher the sealing pressure. The solution provided herein accommodates extrusion gap increase from annular pressure, which cannot be achieved by previous ELH systems available. Another feature includes a proposed metal seal is that the seal gland (or recess) outer diameter (OD) may have a slope in an axial direction, with an upstream/uphole end of the recess gland OD larger than the downstream/downhole end OD of the gland, when the annular pressure is exerted downhole of the seal. When annular pressure is exerted uphole of the seal, the seal gland (or recess) outer diameter (OD) will similarly have a slope in an axial direction, with a downstream/downhole end of the recess gland OD larger than the upstream/uphole end OD of the gland This feature further enhances the self-energizing capability of the MTM seal.
In one example, a liner hanger to be positioned within a casing in a wellbore includes at least one spike to secure the liner hanger to the casing, wherein an outer diameter of the at least one spike includes a seal recess (or gland); and a seal object (seal) to be positioned in the seal recess to form a seal with the casing when the liner hanger is hanging on the casing. In some embodiments, the seal object may be an o-ring with at least one hole, slot, or opening on one side in order to introduce annular pressure from within the wellbore to energize the seal object. The o-ring may be metal and may be hollow and may be fitted between the hanger body ribs or spikes as grooves (e.g. dovetail groove). The height of the spikes/ribs is usually lower than the adjacent spikes and can be designed to control the initial compression of the seal at a desired value. The lowered ribs require less expansion force as well. After expansion, the metal seal object creates the initial sealing between the liner hanger and the casing or liner with high contact pressure. The seal recess may have an axial slope. When high annular pressure is applied, in this example from below/downhole of the hanger, the self-energized seal object will be activated in two ways. The seal object is designed such that the applied pressure will be vented into the structure inside the seal object to provide extra stiffness. A piston load on the seal will push it upwards. The bottom of the recess (or groove) is designed with an angled surface which causes a “jamming” effect that increases the contact pressure as the blow pressure below the spike/rib increases. In other examples, the high annular pressure may be applied from uphole/above the hanger, wherein the piston load will push the seal downwards. More detailed examples and embodiments are described below.
In the illustrated embodiment, a liner hanger system 130 (e.g., expandable liner hanger (ELH) system) and liner 132 are positioned within the wellbore 110. In this embodiment, the liner hanger system 130 is shown on a tool string 135. The liner hanger system 130, in at least one embodiment, includes a radially expandable liner hanger (or expandable tubular), and a plurality of continuous anchoring ridges or spikes on an outer surface of the expandable liner hanger, the anchoring spikes configured to engage with an inner surface of the casing 120. In the illustrated embodiment, the radially expandable liner hanger defines an interior passageway and an exterior surface. In accordance with one embodiment, the plurality of anchoring ridges or spikes includes at least one anchoring ridge proximate a distal or downhole end of the expandable liner hanger. The distal end anchoring ridge may have a recess or groove to form an opening in an outer surface thereof for receiving a self-energizing seal object, which in some embodiments may be a metal seal and can form a pressurized metal to metal (MTM) seal with the wellbore tubular 120. In accordance with one embodiment of the disclosure, the radially expandable liner hanger is configured to move from an initial state (as shown in
A setting tool may be used to radially expand the liner hanger outward. Tool string 135 may convey the setting tool, liner hanger system 130, and liner 132 into the wellbore 110, conduct fluid pressure and flow, transmit torque, tensile and compressive force, etc. The setting tool may facilitate conveyance and installation of liner hanger system 130, in part by using the torque, tensile and compressive forces, fluid pressure and flow, etc., as may be delivered by tool string 135.
Even though
As shown, the liner hanger system 130 may be hung, extending downhole from a lower end of a wellbore tubular, such as a liner or the wellbore tubular 120. An annulus may be created between the tubular 120 and the liner hanger system 130. In embodiments, the liner hanger system 130 can support additional wellbore casing, operational tubulars or tubing strings, completion strings, downhole tools, etc., for positioning at greater depths.
As used herein, the terms “tubular,” “liner,” and “casing” are used generally to describe tubular wellbore items, used for various purposes in wellbore operations. Tubulars, liners, and casings can be made from various materials (metal, plastic, composite, etc.), can be expanded or unexpanded as part of an installation procedure, and can be segmented or continuous. In some examples, the liner may be the casing, but may be an extra tubular layer within the casing. It is not necessary for a tubular, liner or casing to be cemented into position. Any type of tubular, liner, or casing may be used in keeping with the principles of the present disclosure.
Although the liner hanger system 130 is shown in a lower downhole end of the wellbore 110, many different configurations and relative positions of the wellbore tubular 120 and the liner hanger system 130 are possible.
The seal recess 215 may include an inner recess surface 228 that is to face opposite of the surface of the wellbore tubular 250 to which the seal is to be formed, wherein the inner surface of the recess 215 has an angled slope, the inner recess surface comprising a lower end that is to be positioned lower in the wellbore and an upper end that is to be positioned higher relative to the lower end, wherein a lower distance from the lower end of the inner surface to the surface of the wellbore tubular 250 is greater than an upper distance from the upper end of the inner surface to the surface of the wellbore tubular 250.
Some embodiments of the expandable liner hanger 205 may include a plurality of additional spikes 240 (or anchoring ridges) along the outer surface thereof for additional support and engagement with the wellbore tubular 250. The additional spikes 240 may also provide sealing capabilities.
As shown in
The seal recess 215 may comprise an upper sloping end that is to be positioned at an upper end of the wellbore and a lower sloping end that is to be positioned at a lower end of the wellbore, wherein a width of the lower sloping end is greater than a width of the upper sloping end. A bottom/radially inner surface 230 of the recess 215 may be sloped or angled radially downward which causes a “jamming” effect that increases the contact pressure within the recess 215 and within the sealing object 220 as the pressure below the sealing spike 210 increases. In some embodiments an outer diameter (OD) of the sealing object 220 may have a slope in an axial/downhole direction, with an upstream/uphole end OD larger than the downstream/downhole end OD of the sealing object 220. This feature may further enhance the self-energizing capability of the seal. In some embodiments, the bottom surface 230 may also be a flat surface, wherein the seal object 220 will still be jammed in the recess from the annular pressure.
The seal object 220 illustrated in
Although the liner hanger system 200 is shown having only one sealing spike 210, and one seal object 220 in a recess 215 of the sealing spike 210, other embodiments may include a plurality of sealing spikes 210. In other embodiments, the at least one sealing spike 210 or plurality of sealing spikes 210 may include a plurality of recesses, each with a seal object positioned therein.
As illustrated in
Another way the seal object may be installed into the seal recess or coupled with the at least one sealing spike may include installing a seal object that is round and having a closed cross-section (such as metal hollow o-ring) using an open-ended wire with proper cross section, and yoke, or clamp type connection which is used for connection and disconnection of the two ends of the seal object. The more pull of the connection, the tighter the seal. As an example, this type of connection is similar to those used in a scuba diving low pressure inflator.
At a block 604, the liner hanger is coupled to a liner. At a block 606, the liner hanger and the liner are lowered downhole into a wellbore.
At a block 608, the liner hanger is sealed with the casing by engaging the liner hanger radially outward, wherein the seal is created between the seal object and the casing as a setting tool is run downhole within the liner hanger. The setting tool pushes the liner hanger radially outward to engage the spikes and at least one spike of the linger hanger with the casing. Annular pressure from within the wellbore exerted on the at least one sealing spike of the liner hanger energizes a seal object, thereby creating a seal between the liner hanger and the casing.
While the aspects of the disclosure are described with reference to various implementations and exploitations, it will be understood that these aspects are illustrative and that the scope of the claims is not limited to them. Many variations, modifications, additions, and improvements are possible.
Plural instances may be provided for components, operations or structures described herein as a single instance. Finally, boundaries between various components, operations and data stores are somewhat arbitrary, and particular operations are illustrated in the context of specific illustrative configurations. Other allocations of functionality are envisioned and may fall within the scope of the disclosure. In general, structures and functionality presented as separate components in the example configurations may be implemented as a combined structure or component. Similarly, structures and functionality presented as a single component may be implemented as separate components. These and other variations, modifications, additions, and improvements may fall within the scope of the disclosure.
The flowcharts are provided to aid in understanding the illustrations and are not to be used to limit the scope of the claims. The flowcharts depict example operations that can vary within the scope of the claims. Additional operations may be performed; fewer operations may be performed; the operations may be performed in parallel; and the operations may be performed in a different order. It will be understood that each block of the flowchart illustrations and/or block diagrams, and combinations of blocks in the flowchart illustrations and/or block diagrams, can be implemented by program code. The program code may be provided to a processor of a general-purpose computer, special purpose computer, or other programmable machine or apparatus.
Use of the phrase “at least one of” preceding a list with the conjunction “and” should not be treated as an exclusive list and should not be construed as a list of categories with one item from each category, unless specifically stated otherwise. A clause that recites “at least one of A, B, and C” can be infringed with only one of the listed items, multiple of the listed items, and one or more of the items in the list and another item not listed.
As used herein, the term “or” is inclusive unless otherwise explicitly noted. Thus, the phrase “at least one of A, B, or C” is satisfied by any element from the set {A, B, C} or any combination thereof, including multiples of any element.
Aspects disclosed herein include:
Aspect A: An apparatus comprising: a liner hanger to be positioned within a wellbore, wherein the liner hanger comprises, at least one spike to secure the liner hanger to a casing within the wellbore, wherein an outer diameter of the at least one spike includes a seal recess; and a seal object to be positioned in the seal recess to form a seal with the casing when the liner hanger is hanging on the casing.
Aspect B: A system comprising: a liner to be positioned in a wellbore; and a liner hanger to be coupled with the liner, wherein the liner hanger comprises, at least one spike to secure the liner hanger to a casing within the wellbore, wherein an outer diameter of the at least one spike includes a seal recess; and a seal object to be positioned in the seal recess to form a seal with the casing when the liner hanger is hanging on the casing.
Aspect C: method comprising: coupling a seal object with at least one spike of a liner hanger, the at least one spike to secure the liner hanger to a casing within a wellbore; wherein an outer diameter of the at least one spike includes a seal recess; and wherein the seal object forms a seal with the casing when the liner hanger is hanging on the liner; coupling the liner hanger with the liner; lowering the liner hanger and the liner downhole into a wellbore; and securing the liner hanger to the casing using the at least one spike to create a seal between the seal object and the casing.
Aspects A, B, and C may have one or more of the following additional elements in combination:
Element 1: wherein the seal object is hollow; Element 2: wherein the seal object comprises at least one opening to introduce annular pressure from within the wellbore into the seal object; Element 3: wherein the annular pressure from within the wellbore is anticipated from below the liner hanger and wherein the at least one opening of the seal object faces toward downhole end of the wellbore after the seal object is positioned in the seal recess; Element 4: wherein the annular pressure from within the wellbore is anticipated from above the liner hanger and the at least one opening of the seal object faces toward an uphole end of the wellbore after the seal object is positioned in the seal recess; Element 5: wherein the seal object comprises an O-ring; Element 6: wherein the seal object is metallic; Element 7: wherein the seal recess includes an inner recess surface that is to face opposite of the surface of the liner to which the seal is to be formed, wherein the inner recess surface has an angled slope; Element 8: wherein the seal recess includes an inner recess surface that is to face opposite of the surface of the liner to which the seal is to be formed, wherein the seal recess comprises a dovetail shape such that a length of the inner recess surface is greater than a length of an opening of the seal recess; Element 9: wherein the at least one spike comprises an upper sloping end that is to be positioned at an upper end of the wellbore and a lower sloping end that is to be positioned at a lower end of the wellbore, wherein a width of the lower sloping end is greater than a width of the upper sloping end; Element 10: wherein the at least one spike extends in a circular ring along an outer perimeter of the liner hanger, wherein the seal object comprises an O-ring having a wavy form; Element 11: wherein a shape of the seal object comprises at least one of a C shape, an X shape, an E shape, or a K shape. Element 12: wherein the seal object is hollow, wherein the seal object comprises at least one opening to introduce annular pressure anticipated from within the wellbore into the seal object, and wherein the at least one opening of the seal object faces toward an end of the wellbore from which the annular pressure is anticipated after the seal object is positioned in the seal recess; and Element 13: wherein the seal object is positioned in a seal recess of the at least one spike, wherein the seal object is hollow and comprises at least one opening to introduce annular pressure anticipated from within the wellbore into the seal object, and wherein the at least one opening of the seal object faces toward an end of the wellbore from which the annular pressure is anticipated after the seal object is positioned in the seal recess.
