Set down unsealing tool and hanging packer

Abstract

The application provides a down-pressing unblocking tool and a hanging packer, and the down-pressing unblocking tool comprises a supporting mechanism, the supporting mechanism comprises an upper joint, a central pipe, an elastic piece, a slip and a cone, wherein the upper end of the central pipe is sleeved on the inner wall of the lower end of the upper joint; the slip is sleeved on the outer wall of the central pipe, the upper end inner wall of the slip is coaxially connected with the lower end outer wall of the upper joint, the lower end inner wall of the slip and the outer wall of the central pipe form a space for inserting the cone, and the inner wall of the slip and the outer wall of the central pipe have a distance, thereby forming a first cavity; the elastic piece is arranged in the first cavity along the length direction of the central pipe; and the cone is inserted into the space. The application effectively solves the technical problems in the prior art, such as that the unblocking ball of the hanging packer is not easy to be accurately positioned and that the lower pipe column of the hanging packer has a falling risk.

Description

Technical Field

[0001] This invention relates to the field of oil and gas field exploration and development technology, and more specifically, to a pressure-type unsealing tool and a suspended packer. Background Technology

[0002] Currently, when implementing staged production enhancement in horizontal wells, production enhancement tools are run into the horizontal section, and a suspended packer is run into the vertical or less inclined section via drill pipe. After the suspended packer suspends the tool string in the horizontal section onto the casing, the drill pipe separates from the suspended packer, and tubing is then run back to reconnect the tool string, which is inserted into the reconnection sealing sleeve on the suspended packer. The existing suspended packer designed by the inventor (Chinese patent: Integrated Suspended Completion Packer and Completion String, Patent No.: ZL 202110810796.7) has an unsealing mechanism at the lower end of the tool, which requires ball-dropping to pressurize and achieve its unsealing function. However, the reliability of unsealing needs to be improved, and it mainly has the following technical defects:

[0003] 1. If the tool is prematurely sealed during the lowering process, the unsealing tool needs to be thrown into the large sleeve, which poses a risk that the ball may not accurately reach the designated position.

[0004] 2. If the packer string is not lifted after the ball is thrown and the pressure is applied to activate the unsealing mechanism, there is a risk of the string below the packer falling into the well. Summary of the Invention

[0005] The purpose of this invention is to address at least one of the aforementioned shortcomings of the prior art. For example, one objective of this invention is to provide a solution that effectively addresses the technical problem of the release ball of a suspended packer not being able to be accurately positioned in the prior art.

[0006] To achieve the above objectives, one aspect of the present invention provides a pressure-type unsealing tool, which includes a support mechanism comprising an upper connector, a central tube, an elastic element, a locking clip, and a cone. The upper end of the central tube is sleeved on the inner wall of the lower end of the upper connector; the locking clip is sleeved on the outer wall of the central tube, with its upper inner wall coaxially connected to the lower outer wall of the upper connector. A space for the cone to be inserted is formed between the lower inner wall of the locking clip and the outer wall of the central tube, and a distance exists between the inner wall of the locking clip and the outer wall of the central tube, thereby forming a first cavity; the elastic element is arranged along the length of the central tube within the first cavity; and the cone is inserted into the space.

[0007] According to an exemplary embodiment of the pressure-type unsealing tool of the present invention, the elastic element may be a compression spring.

[0008] According to an exemplary embodiment of the pressure-type unsealing tool of the present invention, the pressure-type unsealing tool may further include a release mechanism, the release mechanism including a release claw, a release connecting tube, a release sleeve, a release shearing fixing member, a lower connector, and a loading rod, wherein the upper end of the release connecting tube is coaxially connected to the lower end of the cone; the release claw is sleeved between the outer wall of the central tube and the inner wall of the release connecting tube; the upper end of the release claw can be coaxially and sealed to the lower end of the central tube, and the outer wall of the release claw is coaxially connected to the release connecting tube; the outer wall of the release sleeve is coaxially and sealed to the inner wall of the lower end of the release claw; the upper end of the lower connector is coaxially connected to the lower end of the release connecting tube and is fixed to the outer wall of the release sleeve by the release shearing fixing member; the upper end of the loading rod is coaxially and sealed to the lower end of the lower connector, and the lower end of the loading rod is coaxially and sealed to the guide shoe.

[0009] According to an exemplary embodiment of the pressure-type unsealing tool of the present invention, the outer diameter of the guide shoe may exceed the inner diameter of the unsealing sleeve.

[0010] According to an exemplary embodiment of the pressure-type unsealing tool of the present invention, the release mechanism may further include an unsealing ball (e.g., a steel ball), and the lower inner cavity of the release sleeve is provided with a limiting part that cooperates with the unsealing ball.

[0011] According to an exemplary embodiment of the pressure-type unsealing tool of the present invention, the card release and shearing fixing member can be a shear pin or a shearing pin.

[0012] According to an exemplary embodiment of the pressure-type unsealing tool of the present invention, the upper end of the release connecting tube and the lower end of the cone can be coaxially connected by threads; the upper end of the lower connector and the lower end of the release connecting tube are coaxially connected by threads; the upper end of the loading rod and the lower end of the lower connector are coaxially sealed connected by threads, and the lower end of the loading rod and the guide shoe are coaxially sealed connected by threads.

[0013] Another aspect of the present invention provides a suspended packer, the suspended packer comprising a suspended well completion integrated packer and a down-press release tool as described above.

[0014] In another aspect, the present invention provides a pressure-type unsealing method, which is applied to the suspended packer as described above. The unsealing method includes the following unsealing steps: lowering the pressure-type unsealing tool into the unsealing mechanism of the suspended well completion integrated packer and continuing to press down; when the pressure reaches a set value, continuing to lower it until the central tube of the suspended well completion integrated packer is unconstrained, and then lifting the pressure-type unsealing tool; and continuing to lift it up to achieve the unsealing of the suspended well completion integrated packer and bring it out of the completion string along with the pressure-type unsealing tool.

[0015] In another aspect, the present invention provides a pressure-type unsealing method, which is applied to the suspended packer as described above. The unsealing method includes the following unsealing steps: lowering the pressure-type unsealing tool into the unsealing mechanism of the suspended well completion integrated packer and continuing to press down; when the pressure reaches a set value, continuing to lower it until the central tube of the suspended well completion integrated packer is unconstrained, and then lifting the pressure-type unsealing tool; and continuing to lift it up to achieve the unsealing of the suspended well completion integrated packer and bring it out of the completion string along with the pressure-type unsealing tool.

[0016] According to an exemplary embodiment of the pressure-type unsealing method of the present invention, the unsealing method further includes: when an unsealing abnormality occurs in the unsealing step, an unsealing ball is inserted, and pressure is applied to a set pressure value so that the unloading shear pin is cut off, and pressure is continued to push the loading rod, and the loading rod drives the cone to move, thereby realizing the separation of the pressure-type unsealing tool from the suspended well completion integrated packer.

[0017] Compared with the prior art, the beneficial effects of the present invention include:

[0018] 1) If the sealing is pre-set during the tool insertion process, the pressure-type unsealing tool can be accurately positioned to the unsealing mechanism of the suspended packer, increasing the reliability of unsealing and avoiding the risk of unsealing failure due to the ball not accurately reaching the designated position in ball-throwing unsealing.

[0019] 2) Compared with the existing ball-dropping unsealing tool, the pressure-type unsealing tool has added a support mechanism. After unsealing, the suspended packer string is in an upward state, avoiding the risk of the string below the suspended packer falling into the well, and greatly improving the safety of well operations. Attached Figure Description

[0020] The above and other objects and / or features of the present invention will become clearer from the following description taken in conjunction with the accompanying drawings, in which:

[0021] Figure 1 This is a schematic diagram of the structure of a pressure-type unsealing tool, which is an exemplary embodiment of the present invention.

[0022] Figure 2 This is a partial structural schematic diagram of a suspended packer as an exemplary embodiment of the present invention.

[0023] Explanation of reference numerals in the attached figures:

[0024] 1. Upper connector, 2. Central tube, 3. Spring, 4. Slip, 41. Slip plate, 5. Cone, 6. Release pawl, 7. Steel ball, 8. Release connecting tube, 9. Release sleeve, 10. Release shears, 11. Lower connector of the pressure-type release tool, 12. Loading rod, 13. Guide shoe, 14. Release pawl, 15. Release sleeve, 16. Release shears, 17. Lower connector of the suspension packer. Detailed Implementation

[0025] In the following description, the pressure-type unsealing tool and the suspended packer of the present invention will be described in detail with reference to exemplary embodiments.

[0026] In the following, the suspended well completion integrated packer and completion string of this disclosure will be described in detail with reference to exemplary embodiments. In this document, terms such as "first," "second," "third," and "fourth" are merely for ease of description and distinction, and should not be construed as indicating or implying relative importance or a strict order. Terms such as "upper," "lower," "inner," and "outer" are merely for ease of description and to establish relative orientation or positional relationships, and do not indicate or imply that the referred component must have that specific orientation or position. In this application, the "first end" of each component may be the "upper end" shown in the figures, and the "second end" may be the "lower end" shown in the figures. The "upper end" and "lower end" are consistent with the upper and lower directions of the figures themselves, but do not limit the structure of the components of this disclosure. For example, after the orientation of the components shown in the figures changes, the "first end" may also be the "left end" or "upper end" shown in the figures, and the "second end" may be the "right end" or "lower end" shown in the figures, etc.

[0027] Furthermore, the methods for shaft sealing and connection can employ those commonly used in the art (e.g., shaft sealing can be achieved through sealing rings or sealing assemblies, such as sealing assemblies which may include several O-rings and several O-ring back rings, and connections can be made using threaded connections, snap-fit ​​connections, or plug connections), which will not be elaborated upon further in this disclosure. "Abutting" can be understood as two parts being close to or pressed against each other and capable of preventing relative movement between the two parts.

[0028] This invention provides a pressure-type unsealing tool, which includes a support mechanism comprising an upper connector, a central tube, an elastic element, a locking clip, and a cone. The upper end of the central tube is fitted onto the inner wall of the lower end of the upper connector. The locking clip is fitted onto the outer wall of the central tube, with its upper inner wall coaxially connected to the lower outer wall of the upper connector. A space for the cone to be inserted is formed between the lower inner wall of the locking clip and the outer wall of the central tube. A distance exists between the inner wall of the locking clip and the outer wall of the central tube, thus forming a first cavity. The elastic element is arranged along the length of the central tube within the first cavity. The cone is inserted into the space.

[0029] This invention can effectively solve one or more of the technical problems existing in the prior art, such as the difficulty in accurately positioning the unsealing ball of the suspended packer and the risk of the lower tubing of the suspended packer falling.

[0030] Figure 1 This is a schematic diagram of the structure of a pressure-type unsealing tool, which is an exemplary embodiment of the present invention. Figure 2 This is a partial structural schematic diagram of a suspended packer as an exemplary embodiment of the present invention.

[0031] like Figure 1 and 2 As shown in the first exemplary embodiment of this disclosure, the pressure-type unsealing tool includes a support mechanism and a release mechanism that are coaxially connected.

[0032] The support mechanism is located upstream of the pressure-type unsealing tool. Figure 1 (Left side), the support mechanism includes upper connector 1, central tube 2, spring 3, slip 4 and cone 5.

[0033] The upper end of the upper connector 1 is used to connect to the drill pipe (not shown). The upper end of the central tube 2 is sleeved on the inner wall of the lower end of the upper connector 1. In this embodiment, the upper end of the central tube 2 and the lower end of the upper connector 1 are connected by a threaded coaxial seal, but this disclosure is not limited to this, and they can also be detachably connected by fasteners such as screws or bolts.

[0034] The slip 4 is fitted onto the outer wall of the central tube 2. The upper inner wall of the slip 4 is coaxially connected to the lower outer wall of the upper connector 1. There is a distance between the inner wall of the slip 4 and the outer wall of the central tube 2, thus forming a first cavity. The spring 3 is arranged in the first cavity along the length of the central tube 2. The spring 3 can be a compression spring, but this disclosure is not limited to this, and other common elastic components can also be used. The slip 4 has a cylindrical structure. The slip 4 is composed of a number of slip pieces 41 evenly distributed circumferentially. Each slip piece of the slip 4 has a toothed structure on its outer wall. The toothed structure is oriented obliquely downward and forms a certain angle with the outer wall surface of the slip. The inner wall of the slip piece is coaxially connected to the conical surface of the outer wall of the cone 5. Specifically, the lower inner wall of the slip 4 has a smooth conical surface structure that matches the conical surface of the cone 5. A space for the cone 5 to be inserted is formed between the conical surface of the slip 4 and the outer wall of the central tube 2. The cone 5 is fitted onto the central tube 2, and the inner wall of the cone 5 is coaxially connected to the outer wall of the central tube 2. The lower part of the cone 5 is detachably connected to the release connecting tube 8.

[0035] When Kava 4 is subjected to cone 5 (such as...) Figure 1 When squeezed to the left, the slip 4 can move radially outward relative to the cone surface of the cone 5, thus being opened. After the slip 4 is squeezed and opened, the toothed structure on its outer wall surface engages with the inner wall of the return tube (not shown) of the integrated well completion packer, thereby fixing the position of the slip 4 in the return tube and realizing that it is seated in the return tube of the integrated well completion packer.

[0036] The release mechanism is located at the lower part of the support mechanism. The release mechanism includes a release claw 6, a steel ball 7, a release connecting tube 8, a release sleeve 9, a release shear pin 10, a lower connector 11 of the pressure-type unsealing tool, and a loading rod 12.

[0037] The upper end of the release connecting tube 8 is coaxially connected to the lower end of the cone 5 via a thread. In this embodiment, the upper end of the release connecting tube 8 is sleeved on the inner wall of the lower end of the cone 5, but this disclosure is not limited to this, and it can also be detachably connected by fasteners such as screws or bolts.

[0038] The release claw 6 is sleeved between the outer wall of the central tube 2 and the inner wall of the release connecting tube 8. The upper end of the release claw 6 can be coaxially and sealed with the lower end of the central tube 2, and the outer wall of the release claw 6 is coaxially connected with the release connecting tube 8.

[0039] The outer wall of the release sleeve 9 is coaxially and sealed with the inner wall of the lower end of the release claw 6.

[0040] The upper end of the lower connector 11 of the pressure-type unsealing tool is coaxially connected to the lower end of the release connecting tube 8 via a thread, and is fixed to the outer wall of the release sleeve 9 by release clips 10. In this embodiment, the inner wall of the upper end of the lower connector 11 is connected to the outer wall of the lower end of the release connecting tube 8 by a thread, but this disclosure is not limited to this, and they can also be detachably connected by fasteners such as screws or bolts. In addition, there can be multiple release clips 10, and in addition to release clips 10, other shearing fasteners can also be used, such as shear pins, as long as the fastener can be sheared under external force.

[0041] The upper end of the loading rod 12 is coaxially and threadedly sealed to the lower end of the lower connector 11, and the lower end of the loading rod 12 is coaxially and threadedly sealed to the guide shoe 13. In this embodiment, the outer wall of the upper end of the loading rod 12 is coaxially and threadedly sealed to the inner wall of the lower connector 11, and the inner wall of the lower end of the loading rod 12 is coaxially and threadedly sealed to the outer wall of the guide shoe 13. However, this disclosure is not limited to this, and the connection can also be detachably made using fasteners such as screws or bolts. The lower end of the release sleeve 9 has a distance between it and the upper end of the loading rod 12 in its initial position, but when the release clip 10 is cut and the release sleeve 9 moves to the right and approaches the loading rod 12, the upper end face of the loading rod 12 and the lower end face of the release sleeve 9 can abut against each other.

[0042] The outer diameter of the guide shoe 13 exceeds the inner diameter of the release sleeve 15. When the guide shoe 13 reaches the release sleeve, the pressure value increases, thus achieving precise positioning. If the release sleeve is pre-set during the tool insertion process, the downward-pressing release tool can accurately position itself to the release mechanism of the suspension release device, increasing the reliability of the release and avoiding the risk of release failure due to the ball not accurately reaching the designated position during pitch release.

[0043] The steel ball 7 can be a sphere, a quasi-sphere, a hemisphere, or a semi-hemispherical shape, etc. Besides steel balls, other materials can also be used for the unsealing ball. A limiting part that cooperates with the steel ball 7 is provided in the lower inner cavity of the release sleeve 9. The steel ball 7 can be inserted into the inner cavity of the central tube 2 from the upper end of the central tube 2 and abuts against the limiting part to restrict the steel ball 7 from moving further towards the lower end of the release sleeve 9. The steel ball 7, in cooperation with the limiting part, seals the inner cavity of the central tube 2. In this embodiment, the limiting part inside the release sleeve 9 can form a first variable diameter section near the upper end of the release sleeve 9. The first variable diameter section is a section with a gradually decreasing inner diameter formed in the upper part of the release sleeve 9, and the inserted steel ball 7 can seal the first variable diameter section. In other words, the upper part of the slip sleeve 9 forms a limiting part by narrowing its inner diameter. The inner diameter of the slip sleeve 9 at the limiting part is less than or equal to the diameter of the steel ball 7, so that the steel ball 7 is positioned at the limiting part and fits tightly against the inner wall of the slip sleeve 9 to form a seal. However, this disclosure is not limited to this, and the limiting part can also be formed by providing an annular ball seat protruding from the inner wall of the slip sleeve 9.

[0044] In another aspect, the present invention provides a suspended packer comprising the pressure release tool described above.

[0045] In a second exemplary embodiment of this disclosure, the suspended packer includes an integrated suspended completion packer and a pressure-type release tool as described above. The integrated suspended completion packer includes a coaxially connected setting mechanism, a return sleeve, a release mechanism, and a mounting mechanism. The integrated suspended completion packer can be the integrated suspended completion packer of patent CN202110810796.7. The specific components and connection relationships of its setting mechanism, return sleeve, release mechanism, and mounting mechanism are detailed in patent CN202110810796.7 and will not be repeated here. That is, in this embodiment, the suspended packer of the present invention, based on the integrated suspended completion packer of patent CN202110810796.7, also includes the pressure-type release tool as described above. However, this disclosure is not limited to this; the pressure-type release tool can also be applied to other suspended packers.

[0046] The working process and principle of the above-mentioned pressure-type unsealing tool are as follows:

[0047] During on-site construction, if the integrated well completion packer sets prematurely due to abnormal installation, or if it needs to be retrieved during subsequent well workover, a pressure-type release tool can be installed. The tool is then inserted into the packer via the drill pipe. When the release tool's slip 41 passes through the inner wall of the return sleeve (not shown), the compression spring 3 keeps the slip 41 in a retracted state. When the guide shoe 13 reaches the end face of the release sleeve 15, because the outer diameter of the guide shoe 13 is larger than the inner diameter of the release sleeve 15, it continues to press down. When the pressure reaches the set value, the release shear pin 16 is cut, and the guide shoe 13 pushes the release... As the sleeve 15 moves downward, when the outer wall of the unsealing sleeve 15 separates from the inner wall of the unsealing claw 14, the central tube of the suspended packer (not shown) loses its constraint, and the downward-pressing unsealing tool is lifted. The cone 5 drives the release mechanism of the downward-pressing unsealing tool to move to the left, so that the slip 4 of the downward-pressing unsealing tool sits in the return sleeve (not shown) of the packer. If it continues to be lifted, the rubber sleeve assembly (not shown) and slip II (not shown) of the integrated well completion packer can be retracted to the initial position, thereby realizing the unsealing of the integrated well completion packer. The integrated well completion packer can be taken out with the downward-pressing unsealing tool.

[0048] If an unsealing abnormality occurs after the above operation, steel ball 7 can be inserted to pressurize to the set pressure value, cut off the release clip 10, and release sleeve 9 moves down. When the outer wall of release sleeve 9 separates from the inner wall of release claw 6, continue to pressurize. Release sleeve pushes loading rod 12 to the right, and loading rod 12 drives cone 5 to the right, realizing the separation of the downward unsealing tool from the suspended packer.

[0049] The components not shown above can be referred to in Chinese Patent ZL202110810796.7 entitled "Suspended Well Completion Integrated Packer and Completion String," all of which are incorporated herein by reference. For example, the reconnecting sleeve, suspended packer center tube, rubber sleeve assembly, and slip II of the suspended well completion integrated packer not shown above can be the reconnecting sleeve, suspended packer center tube, suspended packer rubber sleeve assembly, and slip II (the second set of slips in Patent CN202110810796.7) of the suspended well completion integrated packer and completion string.

[0050] The pressure-type unsealing tool of the exemplary embodiment of the present invention has the following advantages:

[0051] 1. If the packer is set in advance during the tool lowering process, the pressure-type unpacking tool can be accurately positioned to the unpacking mechanism of the suspended well completion integrated packer, increasing the reliability of unpacking and avoiding the risk of unpacking failure due to the ball not accurately reaching the designated position in ball-drop unpacking.

[0052] 2. Compared with the existing ball-dropping unsealing tool, the pressure-type unsealing tool has added a support mechanism. After unsealing, the tubing string of the integrated well completion packer is in an upward state, avoiding the risk of the tubing string below the integrated well completion packer falling into the well, and greatly improving the safety of well operations.

[0053] Although the present invention has been described above in conjunction with exemplary embodiments and accompanying drawings, those skilled in the art should understand that various modifications can be made to the above embodiments without departing from the spirit and scope of the claims.

Claims

1. A pressure-type unsealing tool, characterized in that, The pressure-type unsealing tool includes a support mechanism, which comprises an upper connector, a central tube, an elastic element, a slip, and a cone. The upper end of the central tube is fitted onto the inner wall of the lower end of the upper connector. The slip is fitted onto the outer wall of the central tube, with its upper inner wall coaxially connected to the lower outer wall of the upper connector. A space for the cone to be inserted is formed between the lower inner wall of the slip and the outer wall of the central tube. A distance exists between the inner wall of the slip and the outer wall of the central tube, thus forming a first cavity. The elastic element is arranged along the length of the central tube within the first cavity. The cone is inserted into the space. The pressure-type unsealing tool also includes a release mechanism, which comprises a release claw, a release connecting tube, a release sleeve, a release shearing fixing component, a lower connector, and a loading rod. The upper end of the release connecting tube is coaxially connected to the lower end of the cone. The release claw is sleeved between the outer wall of the central tube and the inner wall of the release connecting tube. The upper end of the release claw can be coaxially and sealed to the lower end of the central tube, and the outer wall of the release claw is coaxially connected to the release connecting tube. The outer wall of the release sleeve is coaxially and sealed to the inner wall of the lower end of the release claw. The upper end of the lower connector is coaxially connected to the lower end of the release connecting tube and is fixed to the outer wall of the release sleeve by the release shearing fixing component. The upper end of the loading rod is coaxially and sealed to the lower end of the lower connector, and the lower end of the loading rod is coaxially and sealed to the guide shoe. The release mechanism also includes a release ball, and the upper inner cavity of the release sleeve is provided with a limiting part that cooperates with the release ball.

2. The pressure-type unsealing tool according to claim 1, characterized in that, The elastic element is a compression spring.

3. The pressure-type unsealing tool according to claim 1, characterized in that, The outer diameter of the shoe exceeds the inner diameter of the unsealing sleeve.

4. The pressure-type unsealing tool according to claim 1, characterized in that, The release and shearing fastener is a shearing pin or shearing chain.

5. The pressure-type unsealing tool according to claim 1, characterized in that, The upper end of the release connecting tube is coaxially connected to the lower end of the cone via a thread; the upper end of the lower connector is coaxially connected to the lower end of the release connecting tube via a thread; the upper end of the loading rod is coaxially and sealed to the lower end of the lower connector via a thread; and the lower end of the loading rod is coaxially and sealed to the guide shoe via a thread.

6. A suspended packer, characterized in that, The suspended packer includes a suspended well completion integrated packer and a pressure release tool as described in any one of claims 1 to 5.

7. A pressure-type unsealing method, characterized in that, The unsealing method is applied to the suspension packer as described in claim 6, and the unsealing method includes the following unsealing steps: The downward-pressing release tool is lowered into the release mechanism of the integrated packer for well completion and is continued to be pressed down; Once the pressure reaches the set value, continue lowering until the central tube of the integrated well completion packer is unrestrained, and then lift the pressure-type release tool. as well as Continue lifting to release the integrated packer for well completion and bring out the completion string along with the downward-pressing release tool.

8. The pressure-type unsealing method according to claim 7, characterized in that, The unsealing method further includes: when an unsealing abnormality occurs in the unsealing step, an unsealing ball is inserted and pressurized to a set pressure value so that the unloading shear pin is cut off, and pressure is continued to push the loading rod. The loading rod drives the cone to move, thereby separating the downward unsealing tool from the suspended well completion integrated packer.

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