EXTENDABLE LOST COLUMN SUSPENSION DEVICE ASSEMBLY HAVING MULTIPLE DISCREET SLIDING TEETH INSIDE THE SHALLOW GROOVE

Abstract

The invention relates to an extendable lost column suspension assembly and a well system comprising the assembly. In one aspect, the extendable lost column suspension assembly comprises a radially extendable tubular element defining an inner passage and an outer surface, the extendable tubular element having a shallow groove located in the outer surface.The entire extendable lost column suspension device, in accordance with this aspect, further comprises a plurality of discrete sliding teeth placed circumferentially inside the shallow groove around the radially extendable tubular element, the radially extendable tubular element being configured to transition from an initial state in which the plurality of discrete sliding teeth are not in contact with a borehole tubular element to an extended state in which the plurality of discrete sliding teeth are clamped to the borehole tubular element. Figure for the abbreviation: Fig. 1.

Description

Title of the invention: Extendable lost column suspension device assembly having a plurality of discrete sliding teeth inside the shallow groove. CROSS REFERENCE TO AN ASSOCIATED APPLICATION

[0001] This application claims priority from U.S. application serial number 17 / 750,807, filed on May 23, 2022, entitled "Extendable Lost Column Suspension Device Assembly Having a Plurality of Discreet Sliding Teeth Inside the Shallow Groove". CONTEXT

[0002] During drilling operations, it is common practice to "suspend" a lost standoff over casing so that the casing supports a long chain of tubular elements below. As used here, the term "production standoff" refers to a series of connected pipe sections, casing sections, joints, screens, blanks, crossover tools, downhole tools, and the like, inserted into a borehole, whether used for drilling, rework, production, injection, completion, or other processes. A production standoff can be routed in and out of casing and, similarly, a production standoff can be routed into an uncased borehole or borehole section. Furthermore, in many cases, a tool can be used on wire rope or coiled casing instead of a production standoff, as those skilled in the art will recognize.

[0003] Extendable lost column suspension devices can generally be used to secure the lost column inside a pre-set wellbore tubular element (e.g., a casing or a lost column). Extendable lost column suspension devices can be "set" by expanding the lost column suspension device radially outward into gripping and sealing contact with the wellbore tubular element. For example, extendable lost column suspension devices can be extended by using hydraulic pressure to drive a cone, wedge, or scraper into extension through the lost column suspension device.Other processes can be used, such as mechanical stamping, explosive expansion, memory metal expansion, inflatable material expansion, electromagnetic force controlled expansion, etc.

[0004] The expansion process can typically be carried out by means of an adjustment tool used to transport the lost column suspension device in The borehole. The setting tool can be interconnected between a working column (for example, a tubular column consisting of a drill rod or other segmented or continuous tubular elements) and the lost column suspension device. The setting tool can extend the lost column suspension device into an anchoring and sealing engagement with the casing. BRIEF DESCRIPTION

[0005] Reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which:

[0006] [Fig-1] illustrates an embodiment of a well system designed, manufactured and / or operated according to one or more disclosure embodiments;

[0007] [Fig.2] illustrates an elevational view, with cutaway and partial section, of a mode of realization of the well system of [Fig.1], with the entire extendable lost column suspension device in the extended state;

[0008] [Fig.3] illustrates a perspective view of the entire suspension device of extensible lost column of figures 1 and 2 with one or more (e.g., two) continuous anchoring ribs extending radially outwards from the radially extensible tubular element;

[0009] [Fig.4A] illustrates a cross-section of an assembly of an extendable lost column suspension device designed, manufactured and / or operated, as it might exist in its initial state (e.g., not extended or lowered into the hole);

[0010] [Fig.4B] illustrates a cross-section of the entire extendable lost column suspension device of [Fig.4A], as it might exist in its extended state;

[0011] [Fig.4C] illustrates a cross-section of an assembly of an extendable lost column suspension device designed, manufactured and / or operated according to another embodiment, as it might exist in its initial state (for example, not extended or lowered into the hole);

[0012] [Fig.4D] illustrates a cross-section of the entire extendable lost column suspension device of [Fig.4D], as it might exist in its extended state;

[0013] [Fig.5] illustrates a variant embodiment of a well system designed, manufactured and / or operated according to one or more disclosure embodiments;

[0014] [Fig.6] illustrates an elevation view, with cutaway and partial section, of a mode of realization of the well system of [Fig.5], with the entire extendable lost column suspension device in the extended state;

[0015] [Fig.7] illustrates a perspective view of the entire suspension device of a lost, extensible column of figures 5 and 6 with a first shallow groove comprising a first set of a plurality of discrete sliding teeth and a second shallow groove comprising a second set of a plurality of discrete sliding teeth;

[0016] [Fig.8A] illustrates a cross-section of a suspension device assembly expendable lost column designed, manufactured and / or operated, as it might exist in its initial state (e.g., not extended or lowered into the hole);

[0017] [Fig.8B] illustrates a cross-section of the entire extendable lost column suspension device of [Fig.8A], as it might exist in its extended state;

[0018] [Fig.9] illustrates a perspective view of a suspension device assembly expandable lost column, for example similar to the expandable lost column suspension device of Figures 5 and 6, but using an open end ring and thin beams pointing inwards coupled to one of the discrete sliding teeth to hold the plurality of discrete sliding teeth inside the shallow groove;

[0019] [Fig.1OA] illustrates a perspective view of an expandable lost column suspension device assembly, for example similar to the expandable lost column suspension device of Figures 5 and 6, but using a C-ring attached to the discrete sliding teeth to hold the plurality of discrete sliding teeth inside the shallow groove;

[0020] [Fig.1OB] and [Fig.1OC] illustrate cross-sectional views of different embodiments of the C-ring, respectively, to which the discrete sliding teeth are attached, as it may be designed, manufactured and / or used according to this disclosure.

[0021] [Fig. 11 A] and [Fig. 1 IB] illustrate various sets of different extendable lost column suspension devices designed, manufactured and operated according to one or more embodiments of disclosure;

[0022] [Fig.12A], [Fig.12B], [Fig.12C], [Fig.12D], [Fig.12E], [Fig.12F], [Fig.12G], [Fig.12H], [Fig.121] to [Fig.12J] illustrate various different embodiments of an extendable lost column suspension device assembly having a continuous anchoring rib designed, manufactured and placed according to one or more embodiments of the disclosure; and

[0023] [Fig. 13] illustrates another embodiment of a well system comprising an assembly of expandable lost column suspension devices designed, manufactured and / or operated according to one or more embodiments of disclosure. DETAILED DESCRIPTION

[0024] In the drawings and descriptions that follow, identical parts are generally marked throughout the description and all drawings with the same Numerical references, respectively. The figures drawn may be to scale but are not necessarily so. Certain features of the invention may be shown enlarged to scale or in a somewhat simplified form, and it is possible that some details of certain elements may not be shown for the sake of clarity and conciseness. This disclosure may be implemented in embodiments of various forms. Specific embodiments are described in detail and are shown in the drawings, it being understood that this disclosure should be considered as an example of the principles of disclosure and is not intended to limit disclosure to that illustrated and described herein. It should be fully understood that the various teachings of the embodiments described herein may be used separately or in any suitable combination to produce the desired results.Furthermore, all statements in the present invention indicating principles and aspects of disclosure, as well as specific examples thereof, are intended to encompass equivalents thereof.

[0025] Unless otherwise indicated, the use of the terms "connect", "engage", "couple", "fix", or any other similar term describing an interaction between elements, is not intended to limit the interaction to a direct interaction between the elements and may also include an indirect interaction between the elements described.

[0026] Unless otherwise specified, the use of the terms "top," "upper," "upward," "top of hole," "upstream," or similar terms shall be interpreted as generally away from the bottom, the terminal end of a well, regardless of the wellbore's orientation; likewise, the use of the terms "bottom," "lower," "downward," "bottom of hole," or similar terms shall be interpreted as generally toward the bottom, the terminal end of a well, regardless of the wellbore's orientation. The use of any one or more of the preceding terms shall not be interpreted as designating positions along a perfectly vertical or horizontal axis.Unless otherwise indicated, the use of the term "subterranean formation" should be interpreted as encompassing both areas below the exposed Earth's surface and areas below the Earth's surface covered by water, such as oceans or freshwater bodies.

[0027] As can be seen, lost column suspension devices (for example, extendable lost column suspension devices) must support the substantial weight of the production column fixed below. For deep and extra-deep wells, subsea wells, etc., the production column exerts a substantial axial load on the suspension mechanism that engages the lost column suspension device with the casing. There is a need For improved processes and apparatus providing a lost column suspension device having an anchoring mechanism and a sealing mechanism capable of withstanding the substantial axial loads conferred by longer and heavier lost columns. Furthermore, it is necessary in certain situations to improve the performance of lost column suspension device designs that have failed to maintain an adequate axial load in a top-of-hole direction when placed in a slump position by bottom-of-hole pressure.

[0028] Furthermore, the industry currently uses high-quality steels (e.g., with minimum yield strengths of 125 ksi, 140 ksi, 150 ksi, etc.), as well as increased wall thickness, for the wellbore tubular element in many high-pressure / high-temperature applications. This disclosure acknowledges that the higher minimum yield strength and increased wall thickness lead to various problems. For example, this disclosure acknowledges that in such situations, traditional anchor ribs (e.g., with minimum yield strengths of 110 ksi or less) are unable to bite into the wellbore tubular element, and are unable to deform the wellbore tubular element (e.g., into a wave shape) when it is extended.Therefore, traditional anchor ribs, especially when used with high-quality steel wellbore tubing, rely solely on metal-on-metal friction between the ribs and the wellbore tubing for anchoring. Unfortunately, in some applications, metal-on-metal friction does not provide the required anchoring capacity. Furthermore, traditional anchor ribs, again particularly when used with high-quality steel wellbore tubing, fail to provide the necessary high-pressure seal (e.g., from below).

[0029] This disclosure has recognized, for the first time, that the axial load performance of lost column suspension devices can be improved by localized hardening of one or more of the anchor ribs. For example, localized hardening of one or more of the anchor ribs allows one or more ribs to expand, which would not be possible if the entire continuous anchor rib were hardened. In at least one embodiment, one or more of the anchor ribs are locally hardened, such that the locally hardened sections would have a minimum yield strength of at least 175 ksi, or otherwise at least 200 ksi, or at least 250 ksi. For example, in one or more embodiments, one or more of the anchor ribs are locally hardened, so that locally hardened sections would have a minimum yield strength at least as high as the hardness of case-hardened steel (e.g., 300 ksi).

[0030] In at least one embodiment, one or more of the anchor ribs are locally hardened using an additive manufacturing technique. For example, one or more of the anchor ribs can be locally hardened using a direct metal deposition process, for example by using one or more robotic arms to deposit a thin metal having a minimum yield strength of at least 175 ksi onto localized regions of the anchor rib.

[0031] In at least one other embodiment, one or more of the anchor ribs are locally hardened by carburizing. The term carburizing (e.g., including case hardening, carburizing, etc.), as used here, refers to a heat treatment process in which iron or steel absorbs carbon while the metal is heated in the presence of a carbon-containing material, such as charcoal or carbon monoxide. The aim is to make the metal harder. Depending on the time elapsed and the temperature, the affected area can vary in carbon content. Longer carburizing times and higher temperatures generally increase the depth of carbon diffusion.Furthermore, when iron or steel is rapidly cooled by quenching, the higher carbon content on the outer surface becomes hard due to the transformation of austenite into martensite, while the core remains soft and strong as a ferritic and / or pearlitic microstructure.

[0032] The number of anchor ribs having a locally hardened surface for a given design may vary. In at least one embodiment, one or more of the anchor ribs have a locally hardened surface. In yet another embodiment, at least 20% of the anchor ribs have a locally hardened surface, or at least 50% of the anchor ribs. In yet another embodiment, at least 75% of the anchor ribs have a locally hardened surface, or at least 100%.

[0033] This disclosure further acknowledged, for the first time, that the axial load performance of lost column suspension devices can be improved by replacing one or more of the continuous (e.g., circular) anchor ribs with a ring of discrete sliding teeth, each having a minimum yield strength of at least 175 ksi, or alternatively at least 200 ksi, or alternatively at least 250 ksi, or up to 300 ksi or more. In some embodiments, less than all of the continuous anchor ribs are replaced by the ring of discrete sliding teeth. For example, the most continuous anchor ribs at the top and bottom of the hole could be replaced by the ring of discrete sliding teeth, with every other continuous anchor rib being replaced. by the discrete sliding tooth ring, etc. As a result, the discrete sliding tooth ring(s) could be used to enhance anchoring capacity (e.g., the number of discrete sliding tooth rings could be chosen based on the anchoring load requirements of the well system), while the continuous anchoring ribs could be used for sealing capacity (e.g., the number of continuous anchoring ribs could be chosen based on the sealing requirements of the well system).

[0034] In at least one embodiment, the discrete sliding teeth may be positioned inside one or more shallow grooves in the radially expandable tubular element. In one or more embodiments, the discrete sliding teeth are each individually press-fitted into one or more shallow grooves. In one or more other embodiments, the plurality of discrete sliding teeth are coupled to a C-ring that is press-fitted into one or more grooves. In yet another embodiment, the plurality of discrete sliding teeth are coupled to each other using an elastic material that would hold the plurality of discrete sliding teeth inside one or more shallow grooves.In yet another embodiment, the plurality of sliding teeth are coupled to an open end ring by means of thin beams pointing inwards, the thin beams pointing inwards retaining the plurality of sliding teeth within one or more shallow grooves. However, other coupling mechanisms, including adhesives and / or spot welds, could be used to retain the plurality of sliding teeth within the one or more shallow grooves.

[0035] It has been demonstrated that the embodiments disclosed above significantly improve the anchoring capacity of the entire extendable lost column suspension system. For example, finite element analysis (FEA) simulations of the disclosed embodiments show that the anchoring capacity can be improved by at least 30%. Therefore, a 1.5 m extendable lost column suspension system according to this disclosure could provide the same anchoring capacity as a conventional 4 m extendable lost column suspension system.

[0036] Figure 1 illustrates an embodiment of a well system 100 designed, manufactured, and / or operated according to one or more embodiments of the disclosure. The well system 100, in at least one embodiment, comprises a borehole 110 extending through one or more subsurface formations containing hydrocarbons 115. Following the embodiment of Figure 1, a borehole tubular element 120 (for example, a casing column in the embodiment (as illustrated) was installed and cemented inside borehole 110. The borehole tubing element 110 can be made of many different materials and have many different minimum yield strengths and remain within the scope of disclosure. However, this disclosure is particularly useful when the borehole tubing element 110 is made of high-grade steel. For example, the borehole tubing element may have a minimum yield strength of at least 125 ksi in one embodiment, at least 140 ksi in another embodiment, at least 150 ksi in yet another embodiment, and so on, and remain within the scope of disclosure.

[0037] In the illustrated embodiment, a lost column suspension system 130 (for example, an extendable lost column suspension system) is positioned inside the borehole 110. The casing suspension system 130, in at least one embodiment, comprises an extendable cone (not shown), as well as an extendable lost column suspension device assembly 135 arranged around it. In at least one embodiment, the extendable lost column suspension device assembly 135 comprises a radially extendable tubular element 140. In the illustrated embodiment, the radially extendable tubular element 140 defines an inner passage and an outer surface.According to one embodiment, the extendable lost column suspension assembly 135 further comprises one or more continuous anchoring ribs 145 extending radially outwards from the radially extendable tubular element 140. According to one embodiment of the disclosure, the radially extendable tubular element 140 is configured to transition from an initial state (as illustrated) in which the one or more continuous anchoring ribs 145 are not in contact with the borehole tubular element 120, to an extended state (for example, illustrated in [Fig.2]) in which the one or more anchoring ribs 145 are clamped with the borehole tubular element 120.

[0038] According to the embodiment of [Fig. 1], at least one of the one or more continuous anchor ribs 145 has a plurality of locally hardened sections 150 placed circumferentially around it. Without limitation, the plurality of locally hardened sections 150 could have a minimum yield strength of at least 175 ksi, or alternatively, at least 200 ksi or at least 250 ksi. For example, in one or more embodiments, the plurality of locally hardened sections could have a minimum yield strength at least as high as the hardness of case-hardened steel (for example, 300 ksi). The plurality of locally hardened sections 150 can be manufactured using any of the processes described above, or any other process known or subsequently discovered.

[0039] As illustrated, the extendable lost column suspension system 135 can be suspended, extending downhole from a lower end of the wellbore tubular element 120. An annular space 170 can be created between the wellbore tubular element 120 and the lost column suspension system 130. In embodiments, the lost column suspension system 130 can support additional wellbore casing, operational tubular elements or production columns, completion columns, downhole tools, etc., for positioning at greater depths.

[0040] As used herein, the terms "tubular element," "lost column," and "casing" are generally used to describe tubular wellbore components used for various purposes in wellbore operations. Tubular elements, lost columns, and casings can be made from various materials (metal, plastic, composite, etc.), may or may not be extended as part of an installation procedure, and may be segmented or continuous. It is not necessary for a tubular element, production column, or casing to be cemented in position. Any type of tubular element, lost column, or casing can be used in accordance with the principles of the present invention.

[0041] As illustrated in more detail in [Fig. 1], the lost column suspension system 130 can seal and fix an upper end of the extendable lost column suspension assembly 135 near a lower end of the borehole tubular element 120. Alternatively, the lost column suspension system 130 can seal and fix the upper end of the extendable lost column suspension assembly 135 above a window (not shown) formed through a side wall of the borehole tubular element 120, with the extendable lost column suspension assembly 135 extending outward through the window into a branch or side borehole. Thus, it will be understood that many different configurations and relative positions of the borehole tubular element 120 and the lost column suspension system 130 are possible.

[0042] In embodiments, as also shown in [Fig. 1], a setting tool 175 can be connected near the extendable lost column suspension assembly 135 on a working column 180. The working column 180 can carry the setting tool 175, the extendable lost column suspension assembly 135 (for example, comprising the radially extendable tubular element 140 and one or more continuous anchoring ribs 145) into the borehole 110, conduct pressure and fluid flow, transmit torque, tensile and compressive forces, etc. The setting tool 175 can facilitate the transport and installation of the radially extendable tubular element extensible 140 and one or more continuous anchoring ribs 145, partly using torque, tensile and compressive forces, pressure and fluid flow, etc., as delivered by the working column 180.

[0043] In [Fig. 1], the extendable lost column suspension assembly 135 is further illustrated with one or more sealing elements 155 and one or more anchoring ribs 160 positioned on and fixed to the extendable lost column suspension assembly 135. In at least one embodiment, the one or more anchoring ribs function as a primary metal-to-metal seal, while the one or more sealing elements 155 function as a secondary seal. Moreover, in some embodiments, the radially extendable tubular element 140 and the one or more continuous anchoring ribs 145 can also provide a sealing function.According to one embodiment, the one or more anchor ribs 160 may be standard anchor ribs (for example, which might not contain the plurality of localized hardened sections 150), but may be used in conjunction with the one or more continuous anchor ribs 145 having the plurality of localized hardened sections 150. In embodiments, when the entire extendable lost column suspension device assembly 135 is extended, as with an extension cone, into anchorage and sealing engagement with the borehole element 120, the one or more continuous anchor ribs 145 having the plurality of localized hardened sections 150, the one or more sealing elements 155, and the one or more anchor ribs 160 engage inside the borehole tubular element 120.In at least one embodiment, one or more continuous anchoring ribs 145 having a plurality of localized hardened sections 150 and one or more anchoring ribs 160 provide an anchoring function, while each of the one or more continuous anchoring ribs 145 having a plurality of localized hardened sections 150, one or more sealing elements 155 and one or more anchoring ribs 160 provide a sealing function to some degree. These elements are discussed in more detail below.

[0044] Figure 2 illustrates an elevational view, with cutaway and partial section, of an embodiment of the well system 100 of Figure 1, with the entire extendable lost column suspension device 135 in its extended state. Accordingly, one or more continuous anchor ribs 145 having a plurality of localized hardened sections 150 are clamped to the borehole tubular element 120. In at least one embodiment, as illustrated, the one or more continuous anchor ribs 145 may have at least four localized hardened sections 150 arranged circumferentially around them. In at least one embodiment, the at least four localized hardened sections 150 are arranged circumferentially at equidistant intervals around. In at least one other embodiment, the one or more continuous anchoring ribs 145 may have at least eighteen localized hardened sections 150 placed circumferentially around, if not placed circumferentially at equidistant intervals around. In yet another embodiment, the one or more continuous anchoring ribs 145 may have at least twenty-four localized hardened sections 150 placed circumferentially around, if not placed circumferentially at equidistant intervals around.

[0045] In the illustrated embodiment, the plurality of localized hardened sections 150 are a plurality of localized hardened layers placed circumferentially around. According to this embodiment, the plurality of localized hardened layers may have a thickness of 0.25 µm or less.In yet another embodiment, the plurality of hardened layers can have a thickness ranging from 0.025 pm to 0.076 pm.

[0046] In the illustrated embodiment, a plurality of ductile sections 210 are placed between the plurality of locally hardened sections 150. The plurality of ductile sections 210, in at least one embodiment, comprise the same material as the radially expandable tubular element 140, but have not been locally hardened like the locally hardened sections 150. In yet another embodiment, the plurality of ductile sections 210 comprise a material and a minimum yield strength different from those of the radially expandable tubular element 140 and / or the locally hardened sections 150. In at least one embodiment, the plurality of locally hardened sections 150 have a minimum yield strength of hardened section at least 10% greater than a minimum yield strength of ductile section of the plurality of ductile sections 210.In yet another embodiment, the plurality of localized hardened sections 150 have a minimum yield strength of hardened section at least 50% greater than a minimum yield strength of ductile section of the plurality of ductile sections 210. In yet another embodiment, the plurality of localized hardened sections 150 have a minimum yield strength of hardened section at least 100% greater than a minimum yield strength of ductile section of the plurality of ductile sections 210.

[0047] Figure 3 illustrates a perspective view of the entire extendable lost column suspension device 135 of Figures 1 and 2 with one or more (for example, two) continuous anchor ribs 145 extending radially outward from the radially extendable tubular element 140. As illustrated in Figure 3, the one or more continuous anchor ribs 145 have a plurality of localized hardened sections 150 placed circumferentially around them. In this embodiment, the radially extendable tubular element 140 and the one or more continuous anchor ribs 145 comprise the same material. However, the plurality of Localized hardened sections 150 provide the minimum yield strength required to grip the borehole tubular element. The entire extensible lost column suspension device 135 of [Fig. 3] further includes the plurality of ductile sections 210.

[0048] Figure 4A illustrates a cross-section of an extendable lost column suspension assembly 400 designed, manufactured, and / or operated, as it might exist in its initial state (e.g., not extended or lowered into the hole). The extendable lost column suspension assembly 400, in the illustrated embodiment of Figure 4A, comprises at least eighteen localized hardened sections 420 placed circumferentially around a radially extendable tubular element 410. In the illustrated embodiment, the extendable lost column suspension assembly 400 comprises at least twenty-four localized hardened sections 420 placed circumferentially at equidistant intervals. According to the embodiment of Figure 4A, individual sections of ductile sections 430 are placed between the plurality of localized hardened sections 420. According to the embodiment of Figure 4A,4A], in at least one embodiment, the plurality of ductile sections 430 are radially outside the plurality of hardened sections 420 when the radially extensible tubular element 400 is in the initial state.

[0049] In the illustrated embodiment, each of the localized hardened sections 420 extends circumferentially around the radially extensible tubular element 410 by an angle (|3), wherein the plurality of ductile sections 430 each extend circumferentially around the radially extensible tubular element 410 by an angle (Q). In at least one embodiment, the angle (|3) is 20 degrees or less, otherwise 10 degrees or less. In at least one other embodiment, the angle (Q) is 10 degrees or less, otherwise 5 degrees or less. For example, a ratio of the angle (|3) to the angle (Q), in at least one embodiment, is between 4:1 and 1:1.

[0050] Figure 4B illustrates a cross-section of the extendable lost column suspension device assembly 400 of Figure 4A, as it might exist in its extended state. In at least one embodiment, as illustrated, the plurality of ductile sections 430 are no longer radially outside the plurality of hardened sections 420 when the extendable lost column suspension device assembly 400 is in its extended state.

[0051] Figure 4C illustrates a cross-section of an extendable 400c lost column suspension assembly, designed, manufactured, and / or operated, as it might exist in its initial state (e.g., not extended or lowered into the hole). The extendable 400c lost column suspension assembly, in the mode The embodiment illustrated in [Fig. 4A] comprises a single hardened section 420c placed circumferentially around a radially extensible tubular element 410. In the illustrated embodiment, the single hardened section 420c is configured as a C-ring with a cutout 440, which would allow the single hardened section 420c to extend.

[0052] Fig. 4D illustrates a cross-section of the entire 400c extendable lost column suspension device of Fig. 4C, as it might exist in its extended state.

[0053] Figure 5 illustrates an alternative embodiment of a well system 500 designed, manufactured, and / or operated according to one or more embodiments of the disclosure. The well system 500 is similar in many respects to the well system 100 of Figure 1. Therefore, identical reference numbers have been used to indicate similar, or even identical, features. The well system 500 differs substantially from the well system 100 in that it uses a different extendable lost column suspension assembly 535 than the extendable lost column suspension assembly 135 of Figure 1. For example, the extendable lost column suspension assembly 535 does not have one or more continuous anchor ribs 145 having a plurality of localized hardened sections 150 placed circumferentially around them.In contrast, the entire extendable lost column suspension device 535 of [Fig. 5] comprises a shallow groove 542 located in the outer surface of its radially extendable tubular element 540, and a plurality of discrete sliding teeth 545 placed inside the shallow groove 542 circumferentially around the radially extendable tubular element 540. The plurality of discrete sliding teeth 545 of the embodiment of [Fig. 5] provide the same function as the one or more continuous anchoring ribs 145 having the plurality of localized hardened sections 150 placed circumferentially around, which is to grip the borehole tubular element 120 when it is moved from the initial state to the extended state.

[0054] In the illustrated embodiment of [Fig. 5], each of the plurality of discrete sliding teeth 545 has a minimum yield strength of at least 175 ksi. In yet another embodiment, each of the plurality of discrete sliding teeth 545 has a minimum yield strength of at least 200 ksi, and in yet another embodiment, each of the plurality of discrete sliding teeth 545 has a minimum yield strength of at least 250 ksi, or alternatively 300 ksi or more.

[0055] In the illustrated embodiment of [Fig. 5], the extendable lost column suspension device 535 comprises at least four discrete sliding teeth 545 placed circumferentially around the radially extendable tubular element 540 in a given shallow groove 542. For example, the at At least four discrete sliding teeth 545 may be placed circumferentially at equidistant intervals around the radially extendable tubular element 540 for a given shallow groove 542. In yet another embodiment, the extendable lost column suspension device assembly 535 comprises at least eighteen discrete sliding teeth 545 placed circumferentially (for example, circumferentially at equidistant intervals) around the radially extendable tubular element in a given shallow groove 542. In yet another embodiment, the extendable lost column suspension device assembly 535 comprises at least twenty-four discrete sliding teeth 545 placed circumferentially (for example, circumferentially at equidistant intervals) around the radially extendable tubular element in a given shallow groove 542.

[0056] In certain embodiments, the radially expandable element 540 may comprise a plurality of spaced shallow grooves 542. In such an embodiment, a first set of a plurality of discrete sliding teeth could be positioned in a first shallow groove, and a second set of a plurality of discrete sliding teeth could be positioned in a second shallow groove, as illustrated in [Fig. 5]. [Fig. 5] further illustrates four different shallow grooves 542, two of which comprise sets of a plurality of discrete sliding teeth, and two of which do not yet comprise sets of a plurality of discrete sliding teeth. [Fig. 5] further illustrates that one or more continuous anchoring ribs 160 may be positioned between the first and second sets of the plurality of discrete sliding teeth.

[0057] Figure 6 illustrates an elevational view, with cutaway and partial section, of an embodiment of the well system 500 of Figure 5, with the extendable lost column suspension device 535 in its extended state. As a result, the plurality of discrete sliding teeth 545 are clamped to the borehole tubular element 120.

[0058] In some embodiments, the plurality of discrete sliding teeth 545 are individually adjusted by pressure inside the shallow grooves. In the embodiment of [Fig. 5], the plurality of discrete sliding teeth 545 are coupled to each other by means of an elastic material 610 which holds the plurality of discrete sliding teeth 545 inside the shallow groove while the extendable lost column suspension device 535 is lowered into the hole, and until it is moved to the extended state.

[0059] Figure 7 illustrates a perspective view of the entire extendable lost column suspension device 535 of Figures 5 and 6 with a first shallow groove a deep groove 542a comprising a first set of a plurality of discrete sliding teeth 545a and a second shallow groove 542b comprising a second set of a plurality of discrete sliding teeth 545b. [Fig.7] further illustrates a first elastic material 610a which retains the first plurality of discrete sliding teeth 545a inside the first shallow groove 542a, and a second elastic material 610b which retains the second plurality of discrete sliding teeth 545b inside the first shallow groove 542b.

[0060] Figure 8A illustrates a cross-section of an extendable lost column suspension assembly 800 designed, manufactured, and / or operated, as it might exist in its initial state (e.g., not extended or lowered into the hole). In the illustrated embodiment, the extendable lost column suspension assembly 800 comprises at least eighteen discrete sliding teeth 820 located circumferentially inside the shallow groove around the radially extendable tubular element 810. In the illustrated embodiment, the extendable lost column suspension assembly 800 comprises at least twenty-four discrete sliding teeth 820 located circumferentially at equidistant intervals. According to the embodiment of Figure 8A, the elastic material 830 maintains the plurality of discrete sliding teeth 820 within the shallow groove.

[0061] In the illustrated embodiment, each of the discrete sliding teeth 820 extends circumferentially around the radially extensible tubular element at an angle (F). In at least one embodiment, the angle (F) is 30 degrees or less. In yet another embodiment, the angle (F) is 20 degrees or less, or otherwise 10 degrees or less, or 5 degrees or less.

[0062] Fig. 8B illustrates a cross-section of the entire extendable lost column suspension device 800 of Fig. 8A, as it might exist in its extended state.

[0063] Fig. 9 illustrates a perspective view of an assembly of an extendable lost column suspension device 935, for example similar to the extendable lost column suspension device 535 of Figures 5 and 6, but using an open end ring 910 and thin inwardly pointing beams 920 coupled to one of the discrete sliding teeth 545 to hold the plurality of discrete sliding teeth 545 inside the shallow groove.

[0064] Fig. 1OA illustrates a perspective view of an elongated lost column suspension device assembly 1035, for example similar to the elongated lost column suspension device of Figures 5 and 6, but using a C-ring 1010 fixed to the discrete sliding teeth 545 to hold the plurality of discrete sliding teeth 545 inside the shallow groove.

[0065] Figures 10B and 10C illustrate cross-sectional views of different embodiments of the C-ring 1010b, 1010c, respectively, to which the discrete sliding teeth 545 are attached, as it could be designed, manufactured and / or used according to this disclosure.

[0066] Generally, in downhole adjustment, elements subjected to top pressure (top of hole) are typically "reinforced" or enhanced due to the pressure on the internal diameter of the lost column suspension device. Elements subjected to bottom pressure (bottom of hole) are generally placed in a slump position, thereby reducing the contact stress and the performance of the lost column suspension device when responding to a load from below (bottom of hole). The bottom pressure (bottom of hole) can be sealed by placing one or more sealing elements 1110 on the bottom of the expandable lost column suspension device 1100, thus limiting the influence of the slump pressure, as illustrated in [Fig. 11A].Furthermore, the trapped pressure due to the extension of the expandable lost column suspension device 1100, which would negatively influence the annular space between the sealing elements 1110, can be avoided, thus preventing a decrease in the performance of one or more anchor ribs 1120. This can be attributed to the fact that the fluid is able to communicate through stress-relieving features in one or more anchor ribs 1120. Therefore, the stress-relieving features can provide both stress relief and fluidic communication. In another embodiment, as illustrated in [Fig. 1 IB], another sealing subassembly can also be placed above one or more anchor ribs 1120, thereby limiting the ability of the pressure to reduce the contact stress against the wellbore tubular element.In certain scenarios, pressures may be directed from the bottom (downhole) or the top (top of the hole) and / or combined with varying internal pressures, which can impact the contact stress that the 1100 expandable lost column suspension device exerts against the internal diameter of the wellbore tubular element. It should be noted, however, that one or more of the 1120 anchoring ribs, to some degree, may also provide a sealing function.

[0067] Referring to [Fig. 12A], an embodiment of an extendable lost column suspension device assembly 1200a having a continuous anchoring rib 1210a designed, manufactured, and positioned according to one or more embodiments of the disclosure is illustrated. In the embodiment of [Fig. 12A], the continuous anchoring rib 1210a has a localized hardened section 1220a positioned only on its upper surface. The continuous anchoring rib 1210a, in the The illustrated embodiment comprises two inwardly inclined side walls and a flat top surface.

[0068] Referring to [Fig. 12B], an alternative embodiment of an extendable lost column suspension device assembly 1200b having a continuous anchoring rib 1210b designed, manufactured, and positioned according to one or more embodiments of the disclosure is illustrated. In the embodiment of [Fig. 12B], the continuous anchoring rib 1210b comprises a localized hardened section 1220b positioned on its upper surface and partially along its two inwardly inclined lateral walls.

[0069] Referring to [Fig. 12C], an alternative embodiment of an extendable lost column suspension device assembly 1200c having a continuous anchoring rib 1210c designed, manufactured, and positioned according to one or more embodiments of the disclosure is illustrated. In the embodiment of [Fig. 12C], the continuous anchoring rib 1210c comprises a localized hardened section 1220c positioned on its upper surface and extending entirely along its two inwardly inclined lateral walls.

[0070] Referring to [Fig. 12D], an alternative embodiment of an extendable lost column suspension device assembly 1200d having a continuous anchoring rib 1210d designed, manufactured, and positioned according to one or more embodiments of the disclosure is illustrated. In the embodiment of [Fig. 12D], the continuous anchoring rib 1210d has two inwardly inclined side walls, two vertical side walls, and a flat upper surface, and the localized hardened section 1220d is positioned on its upper surface and partially along its two side walls.

[0071] Referring to [Fig. 12E], an alternative embodiment of an extendable lost column suspension device assembly 1200e having a continuous anchoring rib 1210e designed, manufactured, and positioned according to one or more embodiments of the disclosure is illustrated. In the embodiment of [Fig. 12E], the continuous anchoring rib 1210e has two vertical side walls and a flat upper surface, and the localized hardened section 1220e is positioned on its upper surface and partially along its two vertical side walls.

[0072] Referring to [Fig. 12F], an alternative embodiment of an extendable lost column suspension device assembly 1200f having a continuous anchoring rib 1210f designed, manufactured, and placed according to one or more embodiments of the disclosure is illustrated. In the embodiment of [Fig. 12F], the continuous anchoring rib 1210f has two outwardly inclined side walls and a flat upper surface, and the localized hardened section 1220f is positioned on its upper surface and partially along its two outwardly inclined side walls.

[0073] Referring to [Fig. 12G], an alternative embodiment of an extendable lost column suspension device assembly 1200g having a continuous anchoring rib 1210g designed, manufactured, and positioned according to one or more embodiments of the disclosure is illustrated. In the embodiment of [Fig. 12G], the continuous anchoring rib 1210g has two inwardly inclined side walls, two vertical side walls, and a flat upper surface, and the localized hardened section 1220g is positioned on its upper surface and partially along its two inwardly inclined side walls.

[0074] Referring to [Fig. 12H], an alternative embodiment of an extendable lost column suspension device assembly 1200h having a continuous anchoring rib 1210h designed, manufactured, and positioned according to one or more embodiments of the disclosure is illustrated. In the embodiment of [Fig. 12H], the continuous anchoring rib 1210h has two inwardly inclined side walls and a concave upper surface, and the localized hardened section 1220h is positioned on its concave upper surface and partially along its two side walls.

[0075] Referring to [Fig. 121], an alternative embodiment of an extendable lost column suspension device assembly 1200i having a continuous anchoring rib 1210i designed, manufactured, and positioned according to one or more embodiments of the disclosure is illustrated. In the embodiment of [Fig. 121], the continuous anchoring rib 1210i has two inwardly inclined side walls forming a triangle, and the localized hardened section 1220g is partially positioned along its two inwardly inclined side walls.

[0076] Referring to [Fig. 12J], an alternative embodiment of an extendable lost column suspension device assembly 1200j having a continuous anchoring rib 1210j designed, manufactured, and positioned according to one or more embodiments of the disclosure is illustrated. In the embodiment of [Fig. 12J], the continuous anchoring rib 1210j has a circular cross-section, and the localized hardened section 1220g is positioned on a vertex of the circular cross-section. It should be noted that the shapes of the continuous anchoring ribs illustrated in Figures 12A to 12J are also suitable for the plurality of discrete sliding teeth disclosed above.

[0077] Referring to [Fig. 13], an alternative embodiment of a well system 1300 comprising an extendable lost column suspension assembly 1335 designed, manufactured and / or operated according to one or more embodiments of the disclosure is illustrated. The suspension assembly of The extendable lost column 1335 is similar in many respects to the extendable lost column suspension assembly 135 of [Fig. 2]. Accordingly, the same numerals have been used to denote similar, if not identical, features. The extendable lost column suspension assembly 1335 differs essentially from the extendable lost column suspension assembly 135 in that the extendable lost column suspension assembly 1335 has one or more stress-relieving features 1310 defined on it. In some embodiments, a stress-relieving groove or similar feature may be provided to accommodate plastic expansion. The stress-relieving features 1310 may be circumferentially spaced notches or cutouts on one or more anchor ribs 145, as illustrated.Furthermore, stress relief features 1310 can be created by milling. Those skilled in the art will also recognize other stress relief features and geometries. Stress relief features 1310 can also allow fluidic communication between one or more anchor ribs 145.

[0078] The aspects disclosed in the present invention include:

[0079] A. An expandable lost column suspension assembly, the expandable lost column suspension assembly comprising: 1) a radially expandable tubular element defining an inner passage and an outer surface; and 2) one or more continuous anchor ribs extending radially outward from the radially expandable tubular element, at least one of the one or more continuous anchor ribs having a plurality of localized hardened sections placed circumferentially around, the radially expandable tubular element being configured to move from an initial state in which the one or more continuous anchor ribs are not in contact with a borehole tubular element to an extended state in which the one or more continuous anchor ribs are clamped with the borehole tubular element.

[0080] B. A well system, the well system comprising: 1) a borehole extending through one or more subsurface formations; 2) a borehole tubular element positioned inside the borehole; and 3) an extendable lost column suspension assembly positioned inside the borehole tubular element, the extendable lost column suspension assembly comprising: a) a radially extendable tubular element defining an inner passage and an outer surface; and b) one or more continuous anchor ribs extending radially outward from the radially extensible tubular element, at least one of the one or more continuous anchoring ribs having a plurality of localized hardened sections placed circumferentially around, the radially extensible tubular element being configured to move from an initial state in which the one or more continuous anchoring ribs are not in contact with the borehole tubular element to an extended state in which the one or more continuous anchoring ribs are clamped with the borehole tubular element.

[0081] C. An expandable lost column suspension device assembly, the expandable lost column suspension device assembly comprising: 1) a radially expandable tubular element defining an inner passage and an outer surface, the radially expandable tubular element having a shallow groove located in the outer surface; and 2) a plurality of discrete sliding teeth located inside the shallow groove circumferentially around the radially expandable tubular element, the radially expandable tubular element being configured to transition from an initial state in which the plurality of discrete sliding teeth are not in contact with a borehole tubular element to an extended state in which the plurality of discrete sliding teeth are in clamping contact with the borehole tubular element.

[0082] D. A well system, the well system comprising: 1) a borehole extending through one or more subsurface formations; 2) a borehole tubular element positioned inside the borehole; and 3) an extendable lost column suspension assembly positioned inside the borehole tubular element, the extendable lost column suspension assembly comprising: a) a radially extendable tubular element defining an inner passage and an outer surface, the radially extendable tubular element having a shallow groove located in the outer surface;and b) a plurality of discrete sliding teeth positioned inside the shallow groove circumferentially around the radially extendable tubular element, the radially extendable tubular element being configured to transition from an initial state in which the plurality of discrete sliding teeth are not in contact with a borehole tubular element to an extended state in which the plurality of discrete sliding teeth are in clamping contact with the borehole tubular element.

[0083] Aspects A, B, C and D may have one or more of the following additional elements in combination: Element 1: wherein at least one of the one or more continuous anchoring ribs has at least four localized hardened sections placed circumferentially around it. Element 2: wherein the at least four localized hardened sections are placed circumferentially Element 3: wherein at least one of the one or more continuous anchoring ribs has at least eighteen localized hardened sections placed circumferentially around it. Element 4: wherein the at least eighteen localized hardened sections are placed circumferentially at equidistant intervals around it. Element 5: wherein at least one of the one or more continuous anchoring ribs has a plurality of ductile sections placed between the plurality of localized hardened sections. Element 6: wherein the at least eighteen localized hardened sections each extend circumferentially around the radially extensible tubular element at an angle (|3) of 10 degrees or less. Element 7: wherein the plurality of ductile sections each extend circumferentially around the radially extensible tubular element at an angle (Q) of 5 degrees or less.Element 8: wherein the ratio of angle (|3) to angle (Q) is between 4:1 and 1:1. Element 9: wherein the plurality of localized hardened sections have a minimum yield strength of hardened section at least 10% greater than a minimum yield strength of ductile section of the plurality of ductile sections. Element 10: wherein the plurality of localized hardened sections have a minimum yield strength of hardened section at least 50% greater than a minimum yield strength of ductile section of the plurality of ductile sections. Element 11: wherein the plurality of localized hardened sections have a minimum yield strength of hardened section at least 100% greater than a minimum yield strength of ductile section of the plurality of ductile sections.Element 12: wherein the plurality of ductile sections are radially outside the plurality of hardened sections when the radially extensible tubular element is in the initial state. Element 13: wherein the plurality of localized hardened sections are a plurality of localized hardened layers placed circumferentially around them. Element 14: wherein the plurality of hardened layers have a thickness of 0.25 pm or less. Element 15: wherein the plurality of hardened layers have a thickness ranging from 0.025 pm to 0.076 pm. Element 16: wherein each of the plurality of discrete sliding teeth has a minimum yield strength of at least 175 ksi. Element 17: wherein each of the plurality of discrete sliding teeth has a minimum yield strength of at least 200 ksi. Element 18: wherein each of the plurality of discrete sliding teeth has a minimum yield strength of at least 250 ksi.Element 19: wherein the plurality of discrete sliding teeth consists of at least four discrete sliding teeth arranged circumferentially around the radially extensible tubular element. Element 20: wherein the at least four discrete sliding teeth are arranged circumferentially at equidistant intervals around the radially extensible tubular element. Element 21: wherein the plurality of discrete sliding teeth consists of at least eighteen sliding teeth. discrete circumferentially around the radially expandable tubular element. Element 22: wherein the at least eighteen discrete sliding teeth are placed circumferentially at equidistant intervals around the radially expandable tubular element. Element 23: wherein the at least eighteen discrete sliding teeth each extend circumferentially around the radially expandable tubular element at an angle (E) of 10 degrees or less. Element 24: wherein the plurality of discrete sliding teeth are each individually pressure-fitted within the shallow groove. Element 25: wherein the plurality of discrete sliding teeth are configured as a C-ring that is pressure-fitted within the shallow groove.Element 26: wherein the plurality of discrete sliding teeth are coupled to each other by means of an elastic material which retains the plurality of discrete sliding teeth within the shallow groove. Element 27: wherein the plurality of discrete sliding teeth are coupled to an open end ring by means of inwardly pointing thin beams, the inwardly pointing thin beams retaining the plurality of discrete sliding teeth within the shallow groove.Element 28: wherein the shallow groove is a first shallow groove and the plurality of discrete sliding teeth is a first set of a plurality of discrete sliding teeth, and further comprising a second shallow groove situated in the outer surface and a second set of a plurality of discrete sliding teeth located inside the second shallow groove circumferentially around the radially extensible tubular element. Element 29: further comprising one or more continuous anchoring ribs extending radially outwards from the radially extensible tubular element. Element 30: wherein the one or more continuous anchoring ribs are positioned between the first set of a plurality of discrete sliding teeth and the second set of a plurality of discrete sliding teeth.

[0084] The person skilled in the art concerned with this request will understand that other additions, deletions, substitutions and modifications may be made to the embodiments described.

Claims

Demands

1. Extendable lost column suspension assembly (135), comprising: a radially extendable tubular element (140) defining an inner passage and an outer surface, the radially extendable tubular element having a shallow groove located in the outer surface;and a plurality of discrete sliding teeth (545) placed inside the shallow groove circumferentially around the radially expandable tubular element, the radially expandable tubular element being configured to go from an initial state in which the plurality of discrete sliding teeth are not in contact with a borehole tubular element (120) to an extended state in which the plurality of discrete sliding teeth are clamped with the borehole tubular element, in which the plurality of discrete sliding teeth are configured as a C-ring (1010) which is pressure-fitted inside the shallow groove.

2. Extendable lost column suspension assembly according to claim 1, wherein each tooth among the plurality of discrete sliding teeth has a minimum yield strength of at least 175 ksi, or optionally wherein each tooth among the plurality of discrete sliding teeth has a minimum yield strength of at least 200 ksi, or optionally wherein each tooth among the plurality of discrete sliding teeth has a minimum yield strength of at least 250 ksi.

3. Extendable lost column suspension assembly according to claim 1, wherein the plurality of discrete sliding teeth are at least four discrete sliding teeth placed circumferentially around the radially extendable tubular element (540), or optionally wherein the at least four discrete sliding teeth are placed circumferentially at equidistances around the radially extendable tubular element.

4. Extendable lost column suspension assembly according to claim 1, wherein the plurality of discrete sliding teeth are at least eighteen discrete sliding teeth placed circumferentially around the radially extensible tubular element, or optionally wherein the at least eighteen discrete sliding teeth are placed circumferentially at equidistant intervals around the radially extensible tubular element, or optionally wherein the at least eighteen discrete sliding teeth each extend circumferentially around the radially extensible tubular element at an angle (F) of 10 degrees or less

5. Extendable lost column suspension assembly according to claim 1, wherein the plurality of discrete sliding teeth are each individually pressure-adjusted inside the shallow groove.

6. Extendable lost column suspension assembly according to claim 1, wherein the plurality of discrete sliding teeth are coupled to each other using an elastic material (610) which holds the plurality of discrete sliding teeth (545) inside the shallow groove.

7. Extendable lost column suspension assembly according to claim 1, wherein the plurality of discrete sliding teeth (545) are coupled to an open end ring (910) by means of inwardly pointing thin beams (920), the inwardly pointing thin beams retaining the plurality of discrete sliding teeth inside the shallow groove.

8. Extendable lost column suspension assembly according to claim 1, wherein the shallow groove is a first shallow groove (542a) and the plurality of discrete sliding teeth is a first set of a plurality of discrete sliding teeth (545a), and further comprising a second shallow groove (542b) located in the outer surface and a second set of a plurality of discrete sliding teeth (545b) located inside the second shallow groove circumferentially around the radially extendable tubular element, or optionally further comprising one or more continuous anchoring ribs extending radially outwards from the radially extendable tubular element, or optionally, wherein the one or more continuous anchoring ribs are positioned between the first set of a plurality of discrete sliding teeth and the second set of a plurality of discrete sliding teeth.

9. Well system, comprising: a borehole extending through one or more subsurface formations; a borehole tubular element positioned inside the borehole; and an expandable lost column suspension assembly (135) positioned inside the borehole tubular element, the expandable lost column suspension assembly comprising: a radially expandable tubular element (140) defining an inner passage and an outer surface, the radially expandable tubular element having a shallow rib (542) located in the outer surface;and a plurality of discrete sliding teeth (545) placed circumferentially inside the shallow groove around the expandable tubular element, the radially expandable tubular element being configured to move from an initial state in which the plurality of discrete sliding teeth are not in contact with the borehole tubular element to an extended state in which the plurality of discrete sliding teeth are in clamping contact with the borehole tubular element, in which the plurality of discrete sliding teeth are configured as a C-ring (1010) which is pressure-fitted inside the shallow groove.

10. Well system according to claim 9, wherein each tooth among the plurality of discrete sliding teeth has a minimum yield strength of at least 175 ksi, or optionally wherein each tooth among the plurality of discrete sliding teeth has a minimum yield strength of at least 200 ksi, or optionally wherein each tooth among the plurality of discrete sliding teeth has a minimum yield strength of at least 250 ksi.

11. A well system according to claim 9, wherein the plurality of discrete sliding teeth are at least four discrete sliding teeth placed circumferentially around the radially extensible tubular element, or optionally wherein the at least four discrete sliding teeth are placed circumferentially at equidistance around the radially extensible tubular element.

12. Well system according to claim 9, wherein the plurality of discrete sliding teeth are at least eighteen discrete sliding teeth placed circumferentially around the radially extensible tubular element, or optionally wherein the at least eighteen discrete sliding teeth are placed circumferentially at equidistances around the radially extensible tubular element, or optionally wherein the at least eighteen discrete sliding teeth each extend circumferentially around the radially extensible tubular element by an angle (F) of 10 degrees or less.

13. Well system according to claim 9, wherein the plurality of discrete sliding teeth are each individually pressure-fitted inside the shallow groove (542), or optionally wherein the plurality of discrete sliding teeth are coupled to each other using an elastic material (610) which holds the plurality of discrete sliding teeth inside the shallow groove, or optionally wherein the plurality of discrete sliding teeth are coupled to an open end ring (910) by means of thin beams (920) pointing inwards, the thin beams pointing inwards holding the plurality of discrete sliding teeth inside the shallow groove.

14. A well system according to claim 9, wherein the shallow groove is a first shallow groove (542a) and the plurality of discrete sliding teeth is a first set of a plurality of discrete sliding teeth (545a), and further comprising a second shallow groove (542b) located in the outer surface and a second set of a plurality of discrete sliding teeth (545b) located inside the second shallow groove circumferentially around the radially extendable tubular element, or optionally further comprising one or more continuous anchoring ribs (1120) extending radially outward from the radially extendable tubular element, or optionally, wherein the one or more continuous anchoring ribs are positioned between the first set of a plurality of discrete sliding teeth and the second set of a plurality of discrete sliding teeth.

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