WELL TOOL DEVICE FOR TRANSPORTING A HEAT-GENERATING MIXTURE TO A WELL TUBE
Patent Information
- Authority / Receiving Office
- MX · MX
- Patent Type
- Patents
- Current Assignee / Owner
- INTERWELL NORWAY AS
- Filing Date
- 2023-04-19
- Publication Date
- 2026-05-19
Smart Images
Figure MX434174B0
Abstract
Description
WELL TOOL DEVICE FOR TRANSPORTING A HEAT-GENERATING MIXTURE TO A WELL TUBE 7Ca / bn / O7n7 / 3 / YIAI FIELD OF INVENTION The present invention relates to a well tool device for conveying a heat-generating mixture to a well tube. The well tool device comprises an anchoring device. BACKGROUND OF THE INVENTION WO 2013 / 135583 (Interwell Technology) describes a method for abandoning a well or removing a well element. First, a heat-generating mixture is lowered to the desired position in the well. The heat-generating mixture is then ignited to initiate a heat-generating process. The outcome of the heat-generating process depends on the type and quantity of the heat-generating mixture. It may result in a well element at the desired position being removed or cleared, or in several concentric well elements and the material between them melting and subsequently solidifying to form a plug or barrier in the well. The heat-generating mixture can be, for example, thermite, and the heat-generating process will be an exothermic reduction-oxidation reaction known as the thermite reaction. The purpose of the present invention is to provide a well tool device for transporting a heat-generating mixture into the well. One of the objectives is for the well tool device to be simple and cost-effective to use. BRIEF DESCRIPTION OF THE INVENTION The present invention relates to a well tool device for conveying a heat-generating mixture to a well tube, wherein the well tool device comprises: - a top link section; - a main housing section comprising a compartment for the heat-generating mixture; - an anchoring device connected between the upper link section and the main housing section; wherein the main housing section comprises a compartment subsection and a distance subsection, wherein the compartment is located within the compartment subsection and wherein the distance subsection is located above the compartment subsection. In one aspect, a distance subsection height is more than 2 meters, preferably more than 4 meters, and even more preferably more than 5 meters. In one respect, the anchoring device comprises: - a top linking element rotatably connected to the top linking section; - a lower linking element rotatably connected to the distance section; a radially outward-facing surface with a serrated edge for coupling the well tube in the fixed state; where the length of the upper linking element is greater than the length of the lower linking element. In one aspect, the radially outward-facing surface is provided on the upper joint element or on the lower joint element or on a sliding element rotatably connected between the upper linking element and the lower linking element. In one respect, the well tool has a central longitudinal axis. A radial plane is defined as a plane perpendicular to the central longitudinal axis. In one respect, the length of the upper link element is measured between the pivot points of the upper link element and the length of the lower link element is measured between the pivot points of the lower link element. In one respect, the anchoring device has an operational state, in which the sliding element is radially retracted, and a fixed state, in which the sliding element is radially expanded against the well tube. In one aspect, the anchoring device is configured to be in a radially retracted or operational state when lowered into the well tube, and where the anchoring device is configured to be in a radially expanded or fixed state upon reaching the desired location in the well tube. In one aspect, an upper end of the upper linking element is rotatably connected to the upper linking section and a lower end of the upper linking element is rotatably connected to an upper end of the sliding element; and wherein an upper end of the lower linking element is rotatably connected to a lower end of the sliding element and a lower end of the lower linking element is rotatably connected to the distance subsection. In one aspect, a weight on the main casing section is configured to pull the anchoring device into a radial retraction state when the well tool device is suspended from a cable or wire connected to the upper link section. The weight of the main casing section refers here to the weight of the well tool suspended from the lower linking element of the anchoring device. In one aspect, a weight on the upper link section is configured to push the anchoring device into a state of radial expansion when the well tool device located below the anchoring device is held stationary with respect to the well pipe. The well tooling device can be held stationary by lowering it onto a secured object relative to the well pipe. This object can be a plug placed in the well pipe, a protruding portion of the well pipe, the upper end of a section of pipe string located inside the well pipe, the upper end of a cement column within the well pipe, etc. In one respect, the serrated surface is configured to prevent upward movement of the main housing section after ignition of the heat-generating mixture. In one aspect, the sliding element comprises a first, inwardly oriented stop that engages a central rod of the well tool device in the radial retraction state, causing a lower angle between the lower linking element and the central rod to be greater than 0o. The purpose of the stop is to ensure that the anchoring device can be displaced radially outwards to the radial expansion state. In one aspect, the sliding element comprises a first stop; wherein the lower linking element comprises a second stop, wherein a lower angle between the lower linking element and a longitudinal center axis of the well tool device has a maximum value when the first and second stops are coupled together. In one aspect, the maximum value is 85 to 89°. The purpose of the stops is to ensure that the anchoring device can return to its radial retraction state. In one aspect, the sliding element also comprises a third, inwardly oriented stop for coupling the central rod of the well tool device in the radial retraction or operational state. In one aspect, the well tool device comprises three sets of upper linkage elements, sliding elements, and lower linkage elements distributed around the circumference of the anchoring device. The three sets of upper linkage elements, sliding elements, and lower linkage elements are spaced 120° apart. Alternatively, four sets of upper linkage elements, sliding elements, and lower linkage elements are spaced 90° apart. In another variant, there may be a single set comprising one upper linkage element, one sliding element, and one lower linkage element. In one aspect, the well tool device comprises a wheel section comprising a set of wheels. In one respect, the wheels are provided at a first radial distance from a longitudinal central axis of the well tool device, wherein the radially protruding surface of the sliding element is provided at a second radial distance from a longitudinal central axis of the well tool device, the first radial distance being greater than the second radial distance. In one aspect, the wheel section comprises three wheels. The purpose of the wheel section is to reduce friction during the operation of the well tool in the wellbore and to reduce friction during the retrieval of at least portions of the well tool from the wellbore. The purpose of the wheel section is also to center the well tool in the wellbore. In one aspect, the wheel section is provided axially between the anchoring device and the upper link section. In one respect, the wheel section forms part of the anchoring device, in which the wheels and the upper end of the upper linking element are connected to a common support. In one aspect, the distance subsection comprises an elongated casing extending from the center rod. The purpose of the distance subsection is to increase the distance between the anchoring device and the main casing section. During the heat generation process, the distance subsection is designed to melt at least partially, allowing the upper link section, the anchoring device, and the unmelted portions of the distance subsection to be recovered from the wellbore. In one aspect, the well tool device comprises an ignition device for igniting the heat-generating mixture. The ignition device can be activated by an electrical signal received via a cable connected to the upper link interface. Alternatively, the ignition device can be activated by a wireless signal, a timer, a pressure sensor, etc. In one aspect, the upper link section comprises a connection interface. The connection interface can be a wired or cable connection interface. No placement and / or retrieval tools are required to place and / or retrieve the well tool device; a cable or wire is sufficient. The heat from the molten heat-generating mixture is drawn through the thimble-shaped elements to the lower end of the main housing section and to the lower support element. Therefore, the lower end of the main housing section and the lower support element act as a heat sink to cool the thimble-shaped elements. The term “sliding element” is used herein to describe an element having an outwardly facing toothed surface with at least one tooth, wherein the toothed surface is capable of engaging with the inner surface of the wellbore and thereby preventing upward and / or downward movement of the sliding element. Typically, the toothed surface comprises a number of adjacent teeth. The tooth or teeth of the toothed surface may be shaped to prevent only upward movement, only downward movement, or both upward and downward movement. In one aspect, the well tool additionally comprises: a sealing device located beneath the main housing section; where the sealing device comprises: a lower support element comprising a lower wedge surface; an upper wedge surface oriented towards the lower wedge surface; an toroidal ring situated between the lower wedge surface and the upper wedge surface; wherein the sealing element comprises a plurality of thimble-shaped elements inserted together to form a toroid; where the relative axial movement between the lower wedge surface and the upper wedge surface in directions towards each other provides the radial expansion of the sealing element. The upper wedge surface and the lower wedge surface are provided radially away from, and circumferentially around, the longitudinal axis. In one respect, the upper wedge surface is provided at a lower end of the main housing section. In one respect, the lower support element is displaceable with respect to the main housing section in the longitudinal direction. In one respect, the lower support element is connected to the main housing section by means of a bolt. In one respect, the lower support element is slidably arranged around the bolt. Therefore, the bolt allows relative axial movement between the lower wedge surface and the upper wedge surface. In one aspect, the bolt comprises a head section, a threaded end section, and an unthreaded intermediate section between the head section and the threaded end section. In one aspect, the threaded end section is connected by threading to a threaded opening located at the lower end of the main housing section. The lower support element comprises a through-hole slidably arranged around the unthreaded intermediate section of the bolt. In one respect, thimble-shaped items are made of a metal or an alloy of metals. Therefore, a metal-to-metal seal is provided when the sealing element expands radially in contact with the wellbore. The purpose of a metal-to-metal seal is to prevent, or at least significantly reduce, the flow of the heat-generating molten mixture into the area below the well tool during the heat generation process. The purpose of a metal-to-metal seal is also to prevent, or at least significantly reduce, the rise of the fluid heated by the heat generation process from the area below the well tool into the heat-generating molten mixture during the heat generation process, as this could negatively affect the process. Alternatively, the thimble-shaped elements do not fully expand upon contact with the well tube. The radially expanded O-ring will still constrict the heat-generating molten mixture to flow downwards and / or constrict the fluid heated by the heat generation process to rise. In one aspect, the well tool device comprises several overlapping sealing elements, each sealing element comprising a plurality of thimble-shaped elements inserted together to form a toroid. Alternatively, the thimble-shaped elements are made of ceramic or another suitable heat-resistant material. In one respect, the thimble-shaped elements can be coated. The thimble-shaped elements can be coated with a high-temperature polymer. In one aspect, each of the thimble-shaped elements comprises a through-hole, where the thimble-shaped elements are connected to each other by means of a connecting element inserted through the respective holes. In one aspect, the linking element is a cable. The linking element may be elastic to push the sealing element toward the radially retracted state. In one aspect, the linking element is a coil spring. In one aspect, the linking element is a coil spring to push the sealing element toward the radially retracted state. In one aspect, the sealing device further comprises a ratchet device configured to allow relative axial movement between the lower wedge surface and the upper wedge surface in directions toward each other while preventing relative axial movement between the lower wedge surface and the upper wedge surface in opposite directions. In one aspect, a weight on the main casing section is configured to force the sealing device from the radial retraction state to the radial expansion state when the lower support element is held stationary relative to the well tube. The well tooling device can be held stationary by lowering it onto a fixed object relative to the well pipe. The platform can be a plug placed in the well pipe, a portion projecting into the well pipe, or the upper end of a section of pipe string located inside the well pipe. In one respect, the lower support element comprises a downward-facing, substantially flat support surface. The downward-facing support surface is configured to rest against a support surface provided on the well tube. In one respect, the support surface can form part of a plug placed in the well pipe. In one respect, the lower wedge surface is generally oriented upwards, while the upper wedge surface is generally oriented downwards. The terms “upper,” “above,” “lower,” “below,” etc., are used here as terms relative to the well. The parts referred to as “upper” or “above” are relatively closer to the top of the well than the parts referred to as “lower” or “below,” which are relatively closer to the bottom of the well, regardless of whether the well is horizontal, vertical, or inclined. DETAILED DESCRIPTION OF THE INVENTION The following will describe embodiments of the present invention, with reference to the accompanying figures, in which: Fig. 1 shows the well tool device in a radially retracted or operational state; Fig. 2 shows a partial cross-section of the well tool device in the operating state; Fig. 3 shows a partial cross-section of the well tool device in a radially expanded or fixed state; Fig. 4 shows a perspective view of the tool in its operational state; Fig. 5 shows a perspective view of the tool in its fixed state; Figure 6 shows an enlarged cross-sectional perspective view of the sealing device in its operational state; Figure 7 shows an enlarged cross-sectional perspective view of the sealing device in its fixed state; Figure 8 shows an enlarged cross-sectional perspective view of the anchoring device in its operational state; Figure 9 shows an enlarged cross-sectional perspective view of the anchoring device in its fixed state. Fig. 10a shows a side view of the anchoring device in an intermediate state between the operational and fixed states (center rod removed from the figure); Fig. 10b shows a perspective view of the anchoring device in the intermediate state (center rod removed from the figure); Fig. 10c shows a side view of the anchoring device in the fixed state (center rod removed from the figure); Fig. 10d shows a side view of the anchoring device in its operational state; Figures 11a to g show the steps for using the well tool device to perform a plugging and abandonment operation or to perform a well element removal operation. Figures 12a to d show details of the interconnected chain elements; Fig. 13a shows an alternative mode of anchoring in the operational state; Fig. 13b shows a perspective view of Fig. 13a; Fig. 13c shows a perspective view of the alternative mode of the anchoring device in the fixed state. Figures 1 and 2 now refer to a well tool device (10) inside a well pipe (TP). The purpose of the well tool device (10) is to transport a heat-generating mixture (HGM) to a desired location within an oil and / or gas well. The well is typically equipped with a well pipe (TP) cemented or otherwise secured inside the wellbore. The heat-generating mixture (HGM), when ignited by an ignition device (ID), will initiate a heat-generating process. One such heat-generating process may be part of a plugging and abandonment operation, as described in WO 2013 / 135583, i.e., melting the surrounding materials to form a solid plug. Another such heat-generating process may be part of a well-pipe extraction operation, in which the well-pipe (WP) (and possibly also other well-pipes radially outside the inner well-pipe (WP)) is totally or at least partially melted. The objective of this latter operation may be to expose the rock in the wellbore. Yet another heat-generating process may consist of providing heat, for example, to warm a metal, metal alloy, or other material to its liquid state over a period of time. Figures 1 and 2 depict the well tool device (10) comprising a linkage section (11), a main housing section (14), an anchoring device (20), and a sealing device (50). Additionally, the well tool device (10) may include a wheel section (90). These parts are described in more detail below. Centrally located within the well tool device (10) is a mandrel or center rod (12). The center rod (12) is secured to the linking section (11). Other parts of the well tool device (10) are slip-fitted off the center rod (12), as will become clear from the description below. Additionally, Figure 1 shows that the well tool device (10) is defined with a central longitudinal axis ll, where a radial plane is defined as a plane perpendicular to the central longitudinal axis ll. 7CQ / bn / O7n7 / 3 / YIAI Link section (11) Figures 1, 2, 4, and 5 are now referred to. The linking section (11) is provided at the upper end of the well tool device (10) and comprises a connection interface (11a). The connection interface (11a) can be a wire or cable connection interface. A wire or cable (not shown) connects directly to the connection interface (11a). Therefore, in the present embodiment, no setting tool is required to run and set the well tool device (10) in the desired location in the well. No retrieval tool is used when retrieving the tool or parts thereof. Main housing section (14) Figures 1 to 5 are now referred to. The main housing section (14) is located above the sealing device (50) and below the anchoring device (20). The main housing section (14) comprises a compartment subsection (15) and a distance subsection (17) located above the compartment subsection (15). The compartment subsection (15) comprises an outer casing (15a) and a compartment (16) located within the outer casing (15a). The lower end of the outer casing (15a) is closed. The upper end of the outer casing (15a), i.e., the transition zone between the compartment subsection (15) and the distance section (17), is also closed. Therefore, the compartment (16) is a closed compartment. Compartment (16) will generally contain the heat-generating mixture (HGM). In Figures 2 and 3, the heat-generating mixture (HGM) is shown as a particulate material. However, it should be noted that the heat-generating mixture (HGM) may comprise a solid piece of heat-generating material or may comprise heat-generating material in the form of a slurry or fluid. As shown in Figure 2, the main housing section (14) comprises a hole (14a) in which the central rod (12) is provided. The central rod (12) is axially displaceable in the hole (14a). This is also shown in Figures 6 and 7, where a distance D12 between a lower end of the rod (12) and a lower end of the hole (14a) is greater in the operating state (Fig. 6) than in the fixed state (Fig. 7). Figures 1 and 2 show that the main casing section (14) has a height A14, the compartment subsection (15) has a height A15, and the distance section (17) has a height A17. The height A14 is substantially equal to the sum of the heights A15 and A17. It should be noted that the height A15 can be substantially greater than that shown in the figures, as indicated by the rupture line LR15. The height A15 will depend on the amount of heat-generating mixture (HGM) required for operation. It should also be noted that the height A17 can be substantially greater than that shown in the figures, as indicated by the rupture line LR17.The purpose of the distance subsection (17) is to create a distance between the anchoring device (20) and the heat-generating mixture (HGM), to prevent the heat generation process from melting the anchoring device (20) during or at an early stage of the heat generation process. The height A17 of the distance subsection (17) can be more than 2 meters, preferably more than 4 meters, and even more preferably more than 5 meters. Anchoring device (20) The anchoring device will now be described with reference to Figures 8, 9, and 10a to 10d. The anchoring device (20) is connected between the upper link section (11) and the distance section (17). The anchoring device (20) comprises a sliding element (22) with an outwardly oriented radial surface (22a) with a toothed edge for engaging the well pipe (TP) in the fixed state. The anchoring device (20) further comprises an upper linking element (24) rotatably connected between the upper link section (11) and the sliding element (22), and a lower linking element (26) rotatably connected between the sliding element (22) and the main housing section (14). An upper end (24a) of the upper linking element (24) is rotatably connected to the upper link section (11) at a first pivot point PG1, and a lower end (24b) of the upper linking element (24) is rotatably connected to an upper end of the sliding element (22) at a second pivot point PG2.An upper end (26a) of the lower linking element (26) is rotatably connected to a lower end of the sliding element (22) at a third pivot point PG3 and a lower end (26b) of the lower linking element (26) is rotatably connected to the distance subsection (17) at a fourth pivot point PG4. As described above, the central rod (12) is fixed to the upper link section (11). Therefore, by axially displacing the distance subsection (17) with respect to the upper link section (11), the anchoring device (20) can move between its radial retraction state and its radial expansion state. A line drawn between the first and fourth pivot points (P1, P4) is preferably parallel to the central longitudinal axis II. Similarly, a line drawn between the second and third pivot points (P2, P3) when the anchoring device is in its operational or fixed states is preferably parallel to the central longitudinal axis II. The upper connecting element (24) has a length L24 measured between the first and second pivot points (P1, P2). The lower connecting element (26) has a length L26 measured between the third and fourth pivot points (P3, P4). The length L24 is greater than the length L26. Figure 9 further shows an upper angle a24 between the upper link element (24) and the longitudinal axis ll. Here, the upper angle a24 is shown as the angle between a dashed line drawn between P1 and P4 (parallel to the longitudinal axis ll) and a dashed line drawn between P1 and P2. Similarly, Figure 9 shows a lower angle a26 between the lower link element (26) and the longitudinal axis ll. Here, the lower angle a26 is shown as the angle between a dashed line drawn between P1 and P4 (parallel to the longitudinal axis ll) and a dashed line drawn between P1 and P4. Figure 10a shows that the sliding element (22) comprises a first downward-facing stop (22e). It also shows that the lower linking element (26) comprises a second upward-facing stop (26e). Figure 10c shows that the first downward-facing stop (22e) is engaged with the second upward-facing stop (26e), thus defining a maximum value a26max for the lower angle a26. It is not possible to increase the lower angle a26 beyond this maximum value a26max due to the stops (22e, 26e). The purpose of the stops (22e, 26e) is to ensure that the anchoring device (20) can return to the radially retracted state. Figure 10c shows that the sliding element (22) further comprises a third, inwardly oriented stop (22c). Figure 8 shows that this inwardly oriented stop (22c) engages with the center rod (12) of the well tool device (10) in the radially retracted or operating state. The purpose of the third stop (22c) is to ensure that the lower angle α26 between the lower linking element (26) and the center rod (12) is greater than 0°. Consequently, the stop (22c) will ensure that the anchoring device (20) can be moved radially outwards to transition from the radial retraction state to the radial expansion state. The preferred value for the maximum a26max value is 85 to 89°. In the configuration shown in the figures, the maximum a26max value is 87°. The upper linking element (24) can, for example, have an angle a24 between 30 and 45° with respect to a longitudinal axis (ll) in the radial expansion state. As shown in the figures, the well tool device (10) comprises three sets of upper linking elements, sliding elements, and lower linking elements spaced 120° apart around the circumference of the center rod (12). Alternatively, four sets of upper linking elements, sliding elements, and lower linking elements can be distributed 90° apart around the circumference of the central rod (12). Sealing device (50) Reference is now made to Figures 6 and 7. The sealing device (50) is located below the main housing section (14). The sealing device (50) comprises an O-ring (52). The O-ring (52) is shown in detail in Figures 12a, 12b, 12c, and 12d, and comprises a plurality of thimble-shaped elements (70) inserted together to form a toroid. Viewed from the side as in Figure 12b, each thimble-shaped element comprises an outwardly curved zone (72), an inwardly curved zone (73), and possibly a straight zone (71) between zones (72, 73). The outwardly curved zone (72) of one element is inserted into the inwardly curved zone (73) of the adjacent element. The thimble-shaped elements (70) are known from document US2014 / 0190684 (Interwell Technology AS), which describes a plugging device having a sealing element made of an elastomeric material, wherein the thimble-shaped elements are incorporated into the elastomeric material.The purpose of the thimble-shaped elements is to prevent or at least partially reduce the extrusion of the elastomeric material in situations where there is a large pressure differential across the plug. It is described here that a cable may or may not be inserted through an opening (74) in the elements. In the present O-ring (52), the thimble-shaped elements (70) are connected to each other by means of a linking element (75) inserted through the respective holes (74). In this case, the linking element (74) has the function of pushing the sealing element (52) to its radially retracted state. Figure 12b shows that the linking element (75) is a coil spring. Alternatively, the linking element (75) can be an elastic cable for pushing the sealing element (52) to the radially retracted state. The thimble-shaped elements (70) are preferably made of a metal or a metal alloy. They may be coated with a high-temperature polymer. Alternatively, the thimble-shaped elements (70) are made of ceramic or another suitable heat-resistant material. The sealing device (50) further comprises a lower support element (56) comprising a lower wedge surface (56a) and an upper wedge surface (54a) oriented towards the lower wedge surface (56a). The O-ring (52) is located between the lower wedge surface (56a) and the upper wedge surface (54a). The upper wedge surface (54a) and the lower wedge surface (56a) are positioned radially outward and circumferentially around the longitudinal axis II. Similarly, the O-ring (52) is arranged circumferentially around and outward from the longitudinal axis II. The relative axial movement between the lower wedge surface (56a) and the upper wedge surface (54a) towards each other provides the radial expansion of the sealing element (52). Since the toroidal ring (52) is formed by a plurality of thimble-shaped elements, each element will move a relatively small distance away from the other elements when transitioning from the retracted to the expanded state. However, the outwardly curved portion (72) of one element will still insert, at least partially, into the inwardly curved portion (73) of the adjacent element, and the thimble-shaped elements will still form a toroidal ring (conceived as having a larger diameter in the expanded state than in the retracted state). The term “wedge surface” is used here to describe a surface that, when moved toward another “wedge surface,” will wedge the toroidal ring (52) radially outward. It should be noted that both wedge surfaces may have an acute angle with respect to a radial plane. However, it is also possible for one of the surfaces to be oriented in the radial plane while the other is provided with an acute angle with respect to the radial plane. The upper wedge surface (54a) is arranged here at a lower end (18) of the main housing section (14). The lower support element (56) is movable relative to the lower end (18) of the main housing section (14) and is connected to it by a bolt (61). The bolt (61) comprises a head section (61a), a threaded end section (61b), and an unthreaded intermediate section (61c) between the head section (61a) and the threaded end section (61b). The threaded end section (61b) is connected by thread to a threaded opening (62) located at the lower end (18) of the main housing section (14). The lower support element (56) comprises a through-hole (57) slidably arranged around the unthreaded intermediate section (61c) of the bolt (61). The lower support element (56) comprises a substantially flat, downward-facing support surface (58). This surface (58) defines the lower end of the well tool device (10). The sealing device (50) further comprises a ratchet device (80) configured to allow relative axial movement between the lower wedge surface (56a) and the upper wedge surface (54a) in directions towards each other while preventing relative axial movement between the lower wedge surface (56a) and the upper wedge surface (54a) in opposite directions. Therefore, if the lower support element (56) and the lower end (18) of the main housing section (14) move relative to each other, the ratchet device (80) will allow such movement. However, it is not possible for the lower support element (56) and the lower end (18) of the main housing section (14) to move apart again, due to the ratchet device (80). The ratchet device (80) comprises a finger element (81) having a first end (81a) fixed to the lower end (18) and a second end (81b) provided with a toothed surface that engages a toothed surface of a hole (82) provided in the lower support element (56). Wheel section (90) Reference is now made to Figure 10a to d, where it is shown that the well tool device (10) comprises a wheel section (90) comprising a wheel assembly (92). The wheel section (90) is located axially above the anchoring device (20) and below the upper linking section (11). In the present embodiment, the wheel section (90) forms part of the anchoring device (20), in which the wheels (90) and the upper end (24a) of the upper linking element (24) are connected to a common support (29). However, the wheels (90) are located axially above the sliding element (22). The wheel section (90) comprises three wheels (92). The purpose of the wheel section (90) is to reduce friction during the operation of the well tool device in the well pipe (HP) and to reduce friction during the retrieval of at least portions of the well tool device (10) from the well pipe (HP). The purpose of the wheel section (90) is also to center the well tool device (10) in the well pipe (HP). Reference is now made to Figure 10d, which shows the anchoring device in its operational state. Here, the wheels (92), or more precisely the outward-facing surfaces of the respective wheels (92), are provided at a first radial distance r92 from a longitudinal center axis ll of the well tool device (10). Furthermore, the radially projecting surface (22a) of the sliding element (22) is provided at a second radial distance r22a from a longitudinal center axis ll of the well tool device (10). It is evident that the first radial distance r92 is greater than the second radial distance r22a. Therefore, the wheels also prevent the toothed surface (22-) of the sliding element (22) from accidentally coming into contact with the inner surface of the well pipe during running or retrieval. Operation of the well tool device Initially, reference is made to Figure 2, which shows a top weight (P11) representing the weight of the upper connecting section (11). Since the central rod (12) is fixed to this upper connecting section (11), the weight of the central rod (12) will be included in this top weight (P11). In Figure 2, a lower weight (P14) is shown to represent the weight of the main casing section (14), including the weight of the heat generating mixture (MGC). The operation of the well tool device (10) will now be described with reference to Figures 11a to 11g. Figure 11a shows an oil / gas well (PZ) comprising a wellbore (TP) installed in the well (PZ). The wellbore (TP) here may be a production pipe. On the outer radial portion of the wellbore (PZ) is a well casing (RP) cemented into the formation. An annular space exists between the wellbore (TP) and the well casing (RP). The annular space may be filled with a fluid or with cement. A permanent plug (TAP) has been placed in the well tube (TP). The top of the permanent plug (TAP) forms a bearing surface (SA) for the well tool device (10). Figure 11b shows that the well tool device (10) has been lowered or inserted into the well pipe (TP) by means of a cable (C) to a position above the bearing surface (SA). During this running operation, the weight P14 of the main casing section (14) is pulling the anchor device (20) toward its radially retracted state. As described above, the main casing section (14) is suspended by the lower linking element (26) of the anchor device (20), and therefore the weight P14 will pull the anchor device (20) downward and radially inward to the retracted state. Figure 1c shows that the well tool device (10) has been lowered until the downward-facing bearing surface (58) rests against the bearing surface (SA). As shown, there is no tension in the cable (C). The weight P14 of the main housing section (14) now pushes the upper wedge surface (54a) downward, toward the lower wedge surface (56a), bringing the sealing device (50) from the radially retracted state to the radially expanded state. In this embodiment, the O-ring (52) expands until it contacts the inner surface of the well pipe (TP). When the sealing device is in its radially expanded state, the main housing section (14) becomes stationary with respect to the well pipe (TP). Since the main casing section 14 is now stationary, the weight P11 of the upper link section (11) will push the anchoring device (20) into its radially expanded state. The toothed surface of the sliding element (22) will come into contact with the inner surface of the wellbore, and the anchoring device (20) will now be anchored or coupled to the wellbore. In Figure 12b, the heat-generating mixture (HGM) has been ignited or initiated, and the shaded area represents a heat-generating process (HGP). The heat-generating process (HGP) will melt the compartment subsection (15) and at least portions of the well tube (HT). In the present embodiment, the heat-generating process (HGP) will also melt some of the materials radially external to the well tube (HT), such as the well casing (WC) and the cement present outside the WC. However, due to the distance subsection (17), the heat-generating process (HGP) will not melt the anchoring device (20). Therefore, as shown in Figure 11d, the heat-generating process (HGP) can melt portions of the distance subsection (17), but not all of it. Due to the heat generation process (PGC), fluid pressure typically builds up. The purpose of the anchoring device (20) is to prevent the main casing section (14) from being pushed upward within the wellbore due to this fluid pressure. In this way, the heat generation process remains contained within the desired area of the wellbore. This pressure can become substantial. However, because the lower connecting element (26) is shorter than the upper connecting element and / or because the lower angle α26 is greater than the upper angle α24, a considerable force will push the toothed surface (22a) of the sliders (22) into the wellbore and prevent the upward movement of the main casing section (14) during the heat generation process (PGC). Another consequence of the heat generation process (PGC) is that the materials melt. The metal-to-metal seal provided when the sealing element (52) expands radially in contact with the well tube (TP) will prevent or at least considerably reduce the mixing of molten heat generation fluid and other molten materials (e.g., molten metal from the well tube) from flowing down to the area below the well tool device (10) during the heat generation process. Another consequence of the heat generation process (PGC) is that the fluid in the compartment (CO) between the permanent plug (TAP) and the bearing surface (58) will begin to boil. Therefore, another purpose of the metal-to-metal seal is to prevent, or at least significantly reduce, the rise of the heat-generating fluid from the compartment (CO) below the well tool device into the molten heat mixture during the heat generation process, as this could negatively affect the process. In the final stage of the heat generation process (PGC), the upper link section (11), the anchoring device (20), and possibly also parts of the distance subsection (17) can be retrieved from the well pipe by pulling on the cable, as indicated by the arrow adjacent to the cable (C). The operation is complete. Reference is now made to Figure 11e, which shows an optional step performed before the well tool device (10) is lowered into the well pipe (HP). In this example, the annular space (AS) is filled with fluid. Here, a tool such as that described in W02006098634 (CannSeal AS), WO2010147476 (CannSeal AS), or WO2019112438 (CannSeal AS) is used to first perforate the well pipe (HP) as shown in Figure 11e by means of a tool (CS). Then, as shown in Figure 11f, the tool (CS) injects a fluid-phase sealing material into the perforations, where the fluid-phase material subsequently solidifies to form a barrier in the annular space. The wellbore can also be filled above the permanent plug with this material to fill the compartment (CO) and prevent the aforementioned boiling problems. It is also possible to inject particulate material into the perforations. Furthermore, it is possible to inject a material such as a heat-generating mixture or a material that is part of or affects the heat-generating process into the perforations, either instead of or after the aforementioned sealing material. In Figure 11g, the well tool device (10) has been lowered onto the support surface (SA) formed by the injected and solidified material. It should be noted that if the previous drilling process has damaged the well tube and made it difficult to obtain a metal-to-metal seal between the O-ring (52) and the inner surface of the well tube, the sealing device (50) of the well tool device may comprise several O-rings (52) stacked on top of each other, where each O-ring (52) expands radially outward toward the well tube (TP). It should also be noted that the well tool device (10) can be positioned against bearing surfaces (BS) other than a permanent plug. For example, the previously mentioned injected and solidified material, the bearing surface (BS) can also be a portion projecting into the wellbore (WP), the upper end of a tubing string section located within the wellbore, etc. Furthermore, it should be noted that some tubes have variations in their inside diameter and their shape may also vary (for example, a slightly oval cross-section instead of a perfectly circular one). Therefore, in some cases, the thimble-shaped elements (70) do not fully expand upon contact with the well tube (PT). The radially expanded O-ring will still restrict the flow of the heat-generating molten mixture downwards and / or restrict the flow of the fluid heated by the heat generation process upwards. More alternative options Some alternative modalities have been described above. Reference is now made to Figures 13a, 13b, and 13c, which show an alternative modality of the anchoring device (20). This alternative modality has many similarities to the modality described above, and only the differences between the modalities will be described here. The main difference is that here, the anchoring device (20) does not comprise a separate sliding element rotatably connected between the upper linking element (24) and the lower linking element (26). Instead, the lower end of the upper linking element (24) is rotatably connected directly to the upper end of the lower linking element (26), as indicated by the common pivot point designated as (P2, P3) in Figure 13a. The radially outward-facing surface (22a) is located on the lower connecting element (26). Alternatively, it may be provided on the upper connecting element (24). Here, the first stop (22e) is provided on the upper linking element (24), while the second stop (26e) is provided on the lower linking element (26). Similar to the previous embodiment, the lower angle α26 between the lower linking element (26) and a longitudinal center axis ll of the well tool device (10) has a maximum value α26max when the first stop (22e) and the second stop (26e) are engaged. Furthermore, Figure 13a shows that the anchoring device (20) also comprises a third, inwardly oriented stop (22c). Here too, the stop (22c) is provided in contact with the central rod in the operative state. In this embodiment, the stop (22c) is provided as part of the lower connecting element.
Claims
1. A well tool device (10) for conveying a heat-generating mixture (HGM) to a well tube (HT), wherein the well tool device (10) comprises: - an upper link section (11); - a main housing section (14) comprising a compartment (16) for the heat-generating mixture (HGM); - an anchoring device (20) connected between the upper link section (11) and the main housing section (14); wherein the main housing section (14) comprises a compartment subsection (15) and a distance subsection (17), wherein the compartment (16) is located within the compartment subsection (15) and wherein the distance subsection (17) is located above the compartment subsection (15).
2. A well tool device (10) according to claim 1, wherein the anchoring device (20) comprises: - an upper connecting element (24) rotatably attached to the upper connecting section (11); - a lower connecting element (24) rotatably connected to the distance section (17); a radially outward-facing surface (22a) with a toothed edge for engaging the well pipe (HP) in the fixed state; wherein a length (L24) of the upper connecting element (24) is greater than a length (L26) of the lower connecting element (26).
3. A well tool device (10) according to claim 2, wherein the outwardly radially oriented surface (22a) is provided on the upper linking element (24) or on the lower linking element (26) or on a sliding element (22) rotatably connected between the upper linking element (24) and the lower linking element (26).
4. A well tool device (10) according to claim 3, wherein an upper end (24a) of the upper linking element (24) is rotatably connected to the upper linking section (11) and a lower end (24b) of the upper linking element (24) is rotatably connected to an upper end of the sliding element (22); and wherein an upper end (26a) of the lower linking element (26) is rotatably connected to a lower end of the sliding element (22) and a lower end (26b) of the lower linking element (26) is rotatably connected to the distance subsection (17).
5. A well tool device (10) according to any of the preceding claims, wherein a weight (P14) of the main housing section (14) is configured to pull the anchoring device (20) to a radial retraction state when the well tool device (10) is suspended from a cable or wire connected to the upper link section (11).
6. A well tool device (10) according to any of the preceding claims, wherein a weight (P11) of the upper link section (11) is configured to push the anchor device (20) into a radially expanded state when the well tool device (10) located below the anchor device (20) is held stationary with respect to the well pipe (TP).
7. A well tool device (10) according to any of the preceding claims, wherein the toothed surface (22a) is configured to prevent upward directed movement of the main housing section (14) after ignition of the heat generating mixture (HGM).
8. A well tool device (10) according to any of the preceding claims, wherein the sliding element (22) or the upper linking element (24) comprises a first stop (22e); wherein the lower linking element (26) comprises a second stop (26e), wherein a lower angle (a26) between the lower linking element (26) and a longitudinal center axis (ll) of the well tool device (10) has a maximum value (a26max) when the first stop and the second stop are coupled together.
9. A well tool device (10) according to any of the preceding claims, wherein the well tool device (10) comprises three sets of upper linking elements, sliding elements, and lower linking elements distributed around the circumference of the anchoring device (20).
10. A well-drilling tool device (10) according to any of the preceding claims, wherein the well-drilling tool device (10) comprises a wheel section (90) comprising a wheel assembly (92). 7CQ ! bn / O7n7 / 3 / YIAI 11. A well tool device (10) according to claim 10, wherein the wheels (92) are provided at a first radial distance (r92) from a longitudinal center axis (ll) of the well tool device (10), wherein the radially projecting surface (22a) is provided at a second radial distance (r22a) from a longitudinal center axis (ll) of the well tool device (10), the first radial distance (r92) being greater than the second radial distance (r22a).
12. A well-drilling tool device (10) according to any of the preceding claims, wherein the well-drilling tool device (10) further comprises: - a sealing device (50) located below the main housing section (14); wherein the sealing device (50) comprises: - a lower support element (56) comprising a lower wedge surface (56a); - an upper wedge surface (54a) oriented towards the lower wedge surface (56a); - an O-ring (52) located between the lower wedge surface (56a) and the upper wedge surface (54a); wherein the sealing element (52) comprises a plurality of thimble-shaped elements (70) inserted together to form a toroid; - wherein relative axial movement between the lower wedge surface (56a) and the upper wedge surface (54a) towards each other provides radial expansion of the sealing element (52).