Hanging and clamping type temporary plugging tool and temporary plugging method

Abstract

The invention belongs to the technical field of drilling and production tools, and discloses a hanging and clamping type temporary plugging tool and a temporary plugging method. The hanging and clamping type temporary plugging tool comprises a sealing sleeve, a pressure-bearing pipe, a sealing ring, a pushing sleeve, a sliding sleeve, a connecting rod assembly and a fixing sleeve. The outer side of the top end of the sealing sleeve is connected with a pushing cylinder, and the inner side is connected with a center connector. The inner side of the top end of the pressure-bearing pipe is provided with pressure-bearing threads which are in threaded connection with the central joint; the outer side of the top end of the pressure-bearing pipe is connected with the inner wall of the sealing sleeve through a first connecting ring; the sealing ring sleeves the outer side of the bottom end of the sealing sleeve, the push sleeve sleeves the outer side of the pressure-bearing pipe, and the top end of the push sleeve abuts against the bottom end of the sealing ring; the sliding sleeve is arranged on the pressure-bearing pipe in a sleeving mode and connected with the pressure-bearing pipe through a second connecting ring. The connecting rod assembly is arranged between the push sleeve and the sliding sleeve and can rotate outwards to be expanded and then abut against the inner wall of the casing string. The fixed sleeve is in threaded connection with the bottom end of the pressure-bearing pipe and elastically abuts against the bottom end of the sliding sleeve. The problem of setting failure is solved, and smooth implementation of the fracturing process is facilitated.

Description

Technical Field

[0001] The invention relates to the technical field of drilling tools, and in particular to a hanging card type temporary plugging tool and a temporary plugging method. Background Art

[0002] In order to increase the initial production and final recovery of oil and gas, stratified injection and production and multi-stage fracturing have become one of the effective means for the efficient development of unconventional oil and gas resources. Temporary plugging tools can seal the wellbore in stages by setting seals, and are an important device for achieving multi-stage fracturing.

[0003] At present, the temporary plugging tool setting process mainly utilizes the structural method of embedding high-strength buttons on the outer circle of the slip assembly. Under the axial force of the downhole setting tool, the buttons bite into the inner wall of the casing during the outward expansion of the slip to achieve the anchoring of the temporary plugging tool. However, due to reasons such as casing deformation or insufficient button biting depth, the temporary plugging tool is prone to slippage and movement after setting during the construction process, resulting in failure of setting and fracturing. At the same time, the high-strength buttons cannot be dissolved underground, and the particles are small, resulting in a high proportion of residues, which makes it difficult for subsequent return and salvage; when the high-strength buttons bite into the inner wall of the casing to a certain depth under pressure, it will cause local damage to the inner wall of the casing, reduce strength, and increase the risk of casing deformation; secondly, the current temporary plugging tools generally use multi-petal slips to push the sealing ring to achieve sealing, but during the downhole process, the multi-petal slips are prone to premature setting or disintegration due to the obstruction of heavy oil on the well wall, delaying subsequent construction and affecting the economic benefits of a single well. Summary of the invention

[0004] The object of the present invention is to provide a hanging card type temporary plugging tool and a temporary plugging method to solve the problem that the existing temporary plugging tools are prone to failure in setting.

[0005] To achieve this object, the present invention adopts the following technical solutions:

[0006] A temporary plugging tool of a hanging card type is used for internal plugging of a casing string, wherein the casing string comprises an upper casing, a coupling and a lower casing, wherein both ends of the coupling are respectively provided with internal threads to respectively threadably connect the upper casing and the lower casing, and a convex space is formed between the ends of the upper casing and the lower casing and the inner wall of the coupling; the temporary plugging tool of the hanging card type comprises:

[0007] A sealing sleeve, wherein the outer side of the top end of the sealing sleeve is connected to the push cylinder, and the inner side of the sealing sleeve is connected to the center joint;

[0008] A pressure-bearing pipe, wherein the inner side of the top end of the pressure-bearing pipe is provided with a pressure-bearing thread which is threadedly connected to the center joint, and the outer side of the top end of the pressure-bearing pipe is connected to the inner wall of the sealing sleeve through a first connecting ring, and when the push cylinder pushes the sealing sleeve to move relative to the center joint, the sealing sleeve can drive the first connecting ring to slide unidirectionally from the top end to the bottom end on the pressure-bearing pipe;

[0009] A sealing ring, wherein the sealing ring is sleeved on the outer side of the bottom end of the sealing sleeve;

[0010] A push sleeve, the push sleeve is sleeved on the outside of the pressure-bearing pipe, the top end of the push sleeve abuts against the bottom end of the sealing ring, and when the sealing sleeve slides along the pressure-bearing pipe, the sealing ring can gradually deform to abut against the inner wall of the casing string under the interaction between the push sleeve and the sealing sleeve;

[0011] A sliding sleeve, wherein the sliding sleeve is sleeved on the pressure-bearing pipe and connected to the pressure-bearing pipe via a second connecting ring, and the sliding sleeve can drive the second connecting ring to slide unidirectionally from the bottom end to the top end on the pressure-bearing pipe;

[0012] A connecting rod assembly, wherein the connecting rod assembly is arranged between the push sleeve and the sliding sleeve, and when the push sleeve and the sliding sleeve have a relatively close sliding movement on the pressure-bearing pipe, the connecting rod assembly can rotate outward to expand the diameter and abut against the inner wall of the casing string for anchoring or hanging;

[0013] A fixing sleeve is threadedly connected to the bottom end of the pressure-bearing pipe and elastically abuts against the bottom end of the sliding sleeve.

[0014] Preferably, the hanging card type temporary plugging tool also includes a support ring, which is arranged on the outside of the bottom end of the sealing sleeve and abuts the bottom end of the sealing ring. The support ring is formed by a plurality of Z-shaped arc segments overlapping each other. After being compressed, the support ring can expand radially to support the sealing ring.

[0015] Preferably, the outer side of the sealing sleeve is provided with a first outer cylindrical surface, a second outer cylindrical surface, a first outer conical surface and a second outer conical surface in sequence from the top end to the bottom end, the outer diameter of the first outer cylindrical surface is smaller than the outer diameter of the second outer surface, a step surface is formed between the first outer cylindrical surface and the second outer cylindrical surface, the push cylinder is connected to the first outer cylindrical surface and abuts against the step surface; the taper of the first outer conical surface is greater than the taper of the second outer conical surface, the sealing ring and the support ring are both sleeved on the second outer conical surface, and when the support ring and the sealing sleeve slide relative to each other, the second outer conical surface causes the support ring to expand radially; the top end of the inner side of the sealing sleeve is provided with a first inner conical surface, and the first inner conical surface is in mating contact with the center joint.

[0016] Preferably, the inner wall and outer wall of the first connecting ring are respectively provided with a first serrated internal thread and a first serrated external thread, the inner wall and outer wall of the second connecting ring are respectively provided with a second serrated internal thread and a second serrated external thread, the inner wall of the bottom end of the sealing sleeve is provided with a third serrated internal thread, the inner wall of the sliding sleeve is provided with a fourth serrated internal thread, the pressure-bearing pipe is provided with a third serrated external thread and a fourth serrated external thread, the first serrated internal thread and the first serrated external thread are respectively matched and connected with the third serrated external thread and the third serrated internal thread, the second serrated internal thread and the second serrated external thread are respectively matched and connected with the fourth serrated external thread and the fourth serrated internal thread.

[0017] Preferably, the first connecting ring and the second connecting ring are both C-shaped rings with an opening, the pitch of the first serrated external thread is greater than the pitch of the first serrated internal thread, and the pitch of the second serrated external thread is greater than the pitch of the second serrated internal thread.

[0018] Preferably, a second inner conical surface is provided inside the top end of the push sleeve, the second inner conical surface has the same taper as the second outer conical surface of the sealing sleeve, and the second outer conical surface can be slidably connected along the second inner conical surface and then abut against the end of the second inner conical surface.

[0019] Preferably, the connecting rod assembly includes a first connecting rod and a second connecting rod, one end of the first connecting rod is rotatably connected to the push sleeve, and the other end is rotatably connected to the second connecting rod, and the end of the second connecting rod facing away from the first connecting rod is rotatably connected to the sliding sleeve, and pins are provided between the first connecting rod and the push sleeve and between the second connecting rod and the sliding sleeve for initial positioning.

[0020] Preferably, a plurality of mounting holes are provided on the bottom end surface of the sliding sleeve along the circumferential direction, an elastic member is provided in each mounting hole, and two ends of the elastic member respectively abut against the bottom of the mounting hole and the fixed sleeve.

[0021] Preferably, a reaming hole is provided at the top end of the fixed sleeve, the sliding sleeve is inserted into the reaming hole, and the axial depth of the reaming hole is greater than the elastic sliding distance of the sliding sleeve.

[0022] Preferably, the sealing sleeve, the first connecting ring, the pressure pipe, the support ring, the push sleeve, the sliding sleeve, the connecting rod assembly and the fixed sleeve are all made of soluble metal materials, and the sealing ring is made of soluble rubber material. The soluble metal material and the soluble rubber material can be dissolved underground to release the stuck and sealed, and restore the diameter of the casing string.

[0023] A hanging card type temporary plugging method, using the hanging card type temporary plugging tool provided by the present invention, the hanging card type temporary plugging method comprises the following steps:

[0024] The hanging card type temporary plugging tool is lowered into the casing string through the push tube and the center joint and is located in the upper casing above the convex space;

[0025] Keeping the center joint stationary, continue to push the push tube downward, the sealing sleeve drives the first connecting ring to slide downward along the pressure-bearing pipe under the action of the push tube, and the sealing ring gradually deforms to abut against the inner wall of the upper casing under the interaction between the push sleeve and the sealing sleeve;

[0026] Continue to push the push cylinder downward, the connecting rod assembly between the push sleeve and the sliding sleeve rotates outward to expand the diameter and abuts against the inner wall of the upper sleeve, the pressure-bearing pipe is separated from the center joint, and the push cylinder is separated from the sealing sleeve;

[0027] A pressure ball is placed, and after the pressure ball contacts the sealing sleeve, the hanging card type temporary plugging tool realizes the sealing of the casing string;

[0028] When the pressure at the upper end of the hanging card type temporary plugging tool as a whole is greater than the pressure at the lower end, the hanging card type temporary plugging tool slides down until it slides to the point where the connecting rod assembly is separated from the upper casing. Under the elastic abutment of the fixed sleeve and the sliding sleeve, the connecting rod assembly rotates outward for a second time to expand its diameter until it abuts against the inner wall of the coupling. When the hanging card type temporary plugging tool slides down to the end of the lower casing, it stops sliding, thus achieving hanging card anti-slip.

[0029] Preferably, the hanging card type temporary plugging method also includes the step of releasing the hanging card type temporary plugging tool from being stuck and setting the plug: after the fracturing construction is completed, the hanging card type temporary plugging tool dissolves itself under specific temperature and mineralization conditions underground to release the hanging card type temporary plugging tool from being stuck and setting the plug.

[0030] Beneficial effects of the present invention:

[0031] The hanging card type temporary plugging tool provided by the present invention provides a sealing ring on the outer side of the bottom end of the sealing sleeve. When the push cylinder pushes the sealing sleeve to move downward relative to the center joint, the sealing ring can abut and seal with the inner wall of the casing column; a connecting rod assembly is provided between the push sleeve and the sliding sleeve for rotation and diameter expansion. Since the push sleeve and the sliding sleeve are both unidirectional sliding, the connecting rod assembly can abut and anchor with the inner wall of the casing column after rotation. When the hanging card type temporary plugging tool slides down under force, the connecting rod assembly can further rotate and abut with the inner wall of the coupling of the casing column to achieve hanging card positioning and anti-slip, thereby avoiding slippage and movement after sealing, effectively solving the problem of sealing failure, and facilitating the smooth implementation of the fracturing process.

[0032] Compared with the prior art, the hanging card type temporary plugging tool provided by the present invention has a special anchoring structure without a slip button, and the anchoring structure of the connecting rod assembly can withstand a construction pressure difference greater than or equal to 70MPa. The effective plugging time at the bottom of the well is greater than or equal to 24 hours, and the applicable temperature range is 30°C to 150°C. In addition, because the hanging card type temporary plugging tool has no high-strength buttons as a whole, it can be completely dissolved after the construction is completed, there is no insoluble substance or insoluble structural parts are greatly reduced, the proportion of residues after dissolution is extremely low, and the dissolution performance of the hanging card type temporary plugging tool is effectively improved. Since the inner side of the top of the pressure pipe is provided with a pressure-bearing thread connected with the center joint thread, the pressure-bearing thread will not be disengaged until under the specified pressure. Therefore, the lowering and working process of the hanging card type temporary plugging tool is safe and reliable, and it will not disintegrate or seal prematurely when encountering obstacles. It can effectively ensure the smooth construction of staged fracturing, effectively promote the iterative upgrading of conventional temporary plugging tools, and form a new type of hanging card positioning temporary plugging tool structure technology system, which is suitable for large-scale shale oil fracturing operations under different temperature, mineralization and other working conditions, and plays a certain guiding role in the further development of staged fracturing technology.

[0033] The hanging and clamping temporary plugging method provided by the present invention realizes that the connecting rod assembly in the hanging and clamping type temporary plugging tool abuts against the inner wall of the convex space and is hung and clamped on the top of the lower casing through the primary rotation expansion and the secondary rotation expansion of the connecting rod assembly. The convex space structure of the casing column and the one-way sliding setting of the push sleeve and the sliding sleeve are utilized to enable the connecting rod assembly to achieve anti-slip under the elastic abutment action of the sliding sleeve and the fixed sleeve, thereby avoiding the phenomenon of continuous sliding and movement after setting the seal, effectively solving the problem of setting failure and facilitating the smooth implementation of the fracturing process. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a structural schematic diagram of a hanging card type temporary plugging tool provided by an embodiment of the present invention being lowered into a casing string;

[0035] Figure 2 It is a schematic diagram of the state of the hanging card type temporary plugging tool provided by the embodiment of the present invention being set in the casing string;

[0036] Figure 3 It is a schematic diagram of a setting state of a temporary plugging tool provided by an embodiment of the present invention after being stuck in a casing string;

[0037] Figure 4 This is a front view of the initial state of the support ring in the hanging card type temporary plugging tool provided by an embodiment of the present invention;

[0038] Figure 5 yes Figure 4 A side view of the initial state of the middle support ring;

[0039] Figure 6 This is a front view of the state of the support ring in the hanging card type temporary plugging tool provided by the embodiment of the present invention after radial expansion;

[0040] Figure 7 yes Figure 6 Side view of the middle support ring after radial expansion.

[0041] In the figure:

[0042] 1. Push cylinder; 2. Center joint; 3. Sealing sleeve; 4. First connecting ring; 5. Pressure pipe; 6. Sealing ring; 7. Support ring; 71. Z-shaped arc segment; 8. Push sleeve; 9. First cylindrical pin; 10. First pin; 11. First connecting rod; 12. Second cylindrical pin; 13. Second connecting rod; 14. Second pin; 15. Third cylindrical pin; 16. Sliding sleeve; 17. Second connecting ring; 18. Elastic member; 19. Third pin; 20. Fixed sleeve; 21. Upper casing; 22. Coupling; 23. Lower casing; 24. Pressure ball. DETAILED DESCRIPTION

[0043] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0044] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0045] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0046] In the description of this embodiment, the terms "upper", "lower", "right", etc., directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0047] A temporary plugging tool, such as Figure 1-Figure 7 , used for internal plugging of a casing string, the casing string comprises an upper casing 21, a coupling 22 and a lower casing 23, both ends of the coupling 22 are respectively provided with internal threads to respectively threadably connect the upper casing 21 and the lower casing 23, and a convex space is formed between the ends of the upper casing 21 and the lower casing 23 and the inner wall of the coupling 22; the hanging card type temporary plugging tool can be sealed in the upper casing 21 and after sliding down, it is clamped at the top of the lower casing 23 at the convex space to realize the hanging card sealing positioning.

[0048] like Figure 1-Figure 3The hanging card type temporary plugging tool includes a sealing sleeve 3, a pressure-bearing pipe 5, a sealing ring 6, a push sleeve 8, a sliding sleeve 16, a connecting rod assembly and a fixed sleeve 20. The top outer side of the sealing sleeve 3 is connected to a push cylinder 1, and the inner side is connected to a center joint 2. The push cylinder 1 and the center joint 2 are used to send the hanging card type temporary plugging tool to a specified position in the casing string and perform sealing drive control. The inner side of the top end of the pressure-bearing pipe 5 is provided with a pressure-bearing thread which is threadedly connected with the center joint 2. The outer side of the top end of the pressure-bearing pipe 5 is connected with the inner wall of the sealing sleeve 3 through the first connecting ring 4. When the push tube 1 pushes the sealing sleeve 3 to move relative to the center joint 2, the sealing sleeve 3 can drive the first connecting ring 4 to slide unidirectionally from the top end to the bottom end on the pressure-bearing pipe 5. The sealing ring 6 is sleeved on the outer side of the bottom end of the sealing sleeve 3. The sealing ring 6 is used to abut against the inner wall of the upper casing 21 during setting to achieve sealing of the upper casing 21. In the embodiment of the present invention, the sealing ring 6 can be deformed under the pushing action of the push tube 1 to abut against the inner wall of the upper casing 21. The sealing ring 6 is made of soluble rubber material and can be completely dissolved under certain temperature conditions. The push sleeve 8 is sleeved on the outer side of the pressure-bearing pipe 5, and the top of the push sleeve 8 abuts against the bottom end of the sealing ring 6. When the sealing sleeve 3 slides along the pressure-bearing pipe 5, the sealing ring 6 can be gradually deformed to abut against the inner wall of the casing column under the interaction of the push sleeve 8 and the sealing sleeve 3, thereby realizing the sealing between the hanging card type temporary plugging tool and the casing column; the sliding sleeve 16 is sleeved on the pressure-bearing pipe 5 and is connected to the pressure-bearing pipe 5 through the second connecting ring 17, and the sliding sleeve 16 can drive the second connecting ring 17 to slide unidirectionally from the bottom end to the top end on the pressure-bearing pipe 5; the connecting rod assembly is arranged between the push sleeve 8 and the sliding sleeve 16. When the push sleeve 8 and the sliding sleeve 16 have a relatively close sliding movement on the pressure-bearing pipe 5, the connecting rod assembly can rotate outward to expand the diameter and abut against the inner wall of the upper casing 21 or the inner wall of the coupling 22 to realize anchoring or hanging card anti-slip; the fixed sleeve 20 is threadedly connected to the bottom end of the pressure-bearing pipe 5 and elastically abuts against the bottom end of the sliding sleeve 16.

[0049] The hanging card type temporary plugging tool provided by the present invention is provided with a sealing ring 6 and a supporting ring 7 on the outer side of the bottom end of the sealing sleeve 3. When the push cylinder 1 pushes the sealing sleeve 3 to move downward, the sealing ring 6 can be deformed and sealed on the inner wall of the upper casing 21 under the interaction between the push sleeve 8 and the sealing sleeve 3 to ensure the sealing performance of the sealing ring 6; a connecting rod assembly is provided between the push sleeve 8 and the sliding sleeve 16 for rotation and expansion, so that the connecting rod assembly can abut against the inner wall of the upper casing 21 for anchoring after rotation. When the hanging card type temporary plugging tool slides down on the inner wall of the upper casing 21, the connecting rod assembly slides down to the convex space and can continue to rotate to expand the diameter and abut against the inner wall of the coupling 22, and finally stops at the end of the lower casing 23 to achieve non-slip positioning. The hanging card type temporary plugging tool provided by the embodiment of the present invention effectively avoids the phenomenon of slippage and movement of the hanging card type temporary plugging tool after sealing, solves the problem of sealing failure, and is conducive to the smooth implementation of the fracturing process.

[0050] Preferably, the hanging card type temporary plugging tool also includes a support ring 7, which is sleeved on the outer side of the bottom end of the sealing sleeve 3 and abuts against the bottom end of the sealing ring 6. The support ring 7 is formed by a plurality of Z-shaped arc segments 71 overlapping each other. After being compressed, the support ring 7 can expand radially to support the sealing ring 6.

[0051] like Figure 4-Figure 7 As shown, the support ring 7 includes a plurality of Z-shaped arc segments 71, and the plurality of Z-shaped arc segments 71 overlap each other end to end to form the support ring 7, and the support ring 7 is sleeved on the sealing sleeve 3. When the inner hole of the support ring 7 increases in diameter under the action of the sealing sleeve 3, the plurality of Z-shaped arc segments 71 move relative to each other and expand outward, and during the movement and expansion, the plurality of Z-shaped arc segments 71 always maintain at least a partial overlap without separation, and no gaps are generated. Therefore, the support ring 7 can always provide reliable support for the bottom end of the sealing ring 6 during the deformation and sealing of the sealing ring 6, so as to improve the sealing stability and reliability of the sealing ring 6. If gaps are generated between the Z-shaped arc segments 71 after the movement and expansion, the sealing ring 6 will be deformed through the gaps when it is subjected to the pressure at the top, and then the pressure will drop suddenly, causing the seal to fail.

[0052] Preferably, the outer side of the sealing sleeve 3 is provided with a first outer cylindrical surface, a second outer cylindrical surface, a first outer conical surface and a second outer conical surface in sequence from the top end to the bottom end. The outer diameter of the first outer cylindrical surface is smaller than the outer diameter of the second outer surface. A step surface is formed between the first outer cylindrical surface and the second outer cylindrical surface. The push cylinder 1 is connected to the first outer cylindrical surface and abuts against the step surface, so that the push cylinder 1 can be pushed downward at the step surface for sealing drive; the taper of the first outer conical surface is greater than the taper of the second outer conical surface, and the sealing ring 6 and the support ring 7 are both sleeved on the second outer conical surface. When the push cylinder 1 pushes the sealing sleeve 3 downward, the support ring 7 and the sealing sleeve 3 slide relative to each other, and the sealing ring 6 and the sealing sleeve 3 slide relative to each other, that is, the support ring 7 and the sealing ring 6 can slide along the second outer conical surface toward the first outer conical surface. During the sliding process, the sealing ring 6 is extruded and deformed for sealing, and the inner diameter of the support ring 7 is enlarged, and radial expansion occurs to synchronously support the bottom end of the sealing ring 6; the top end of the inner side of the sealing sleeve 3 is provided with a first inner conical surface, and the first inner conical surface is in contact with the center joint 2 for installation positioning and guiding.

[0053] like Figure 1In the initial state, the first inner cone surface is installed in cooperation with the third outer cone surface on the center joint 2. After the hanging card temporary plugging tool is lowered to the sealing position in the casing string, the pressure-bearing thread can be sheared under the thrust of the push tube 1, so that the center joint 2 and the pressure-bearing pipe 5 are separated. At this time, the first inner cone surface is used to carry the pressure ball 24 used for sealing, so that the pressure ball 24 can be stably sealed in the sealing sleeve 3 to seal the inner hole of the pressure-bearing pipe 5. Furthermore, the bottom end of the center joint 2 is also provided with a fourth outer cone surface, and the fourth outer cone surface is used to cooperate with the second inner cone surface at the top of the pressure-bearing pipe 5 to facilitate the connection positioning and guiding between the pressure-bearing pipe 5 and the center joint 2. It should be noted that the outer wall of the top end of the pressure-bearing pipe 5 is provided with a pressure-bearing thread, and the outer wall of the bottom end of the center joint 2 is provided with an outer thread. The threaded connection between the pressure-bearing pipe 5 and the center joint 2 is initially connected and fixed.

[0054] Preferably, the inner wall and outer wall of the first connecting ring 4 are respectively provided with a first serrated internal thread and a first serrated external thread, the inner wall and outer wall of the second connecting ring 17 are respectively provided with a second serrated internal thread and a second serrated external thread, the inner wall of the bottom end of the sealing sleeve 3 is provided with a third serrated internal thread, the inner wall of the sliding sleeve 16 is provided with a fourth serrated internal thread, and the pressure pipe 5 is provided with a third serrated external thread and a fourth serrated external thread, the first serrated internal thread and the first serrated external thread are respectively cooperated and connected with the third serrated external thread and the third serrated internal thread, so that the sealing sleeve 3 can slide unidirectionally from the top end to the bottom end along the pressure pipe 5, and the second serrated internal thread and the second serrated external thread are respectively cooperated and connected with the fourth serrated external thread and the fourth serrated internal thread, so that the sliding sleeve 16 can slide unidirectionally from the bottom end to the top end along the pressure pipe 5.

[0055] like Figure 1 As shown, the function of the first connecting ring 4 and the second connecting ring 17 is that after the first connecting ring 4 and the second connecting ring 17 slide on the pressure pipe 5, according to the non-return effect of the serrated thread, the push sleeve 8 and the sliding sleeve 16 can be prevented from moving in the reverse direction, thereby ensuring that the connecting rod assembly will not rotate in the reverse direction after the diameter is expanded, thereby ensuring that the connecting rod assembly can reliably abut against the inner wall of the upper casing 21 and the inner wall of the coupling 22.

[0056] Preferably, the first connecting ring 4 and the second connecting ring 17 are both C-shaped rings with an opening, the pitch of the first serrated external thread is greater than the pitch of the first serrated internal thread, and the pitch of the second serrated external thread is greater than the pitch of the second serrated internal thread.

[0057] It can be understood that the C-shaped ring with an opening is conducive to expansion after being subjected to force. When the sealing sleeve 3 moves along the pressure-bearing pipe 5 under the action of the push tube 1, the sealing sleeve 3 drives the first connecting ring 4 to move on the pressure-bearing pipe 5. Due to the setting of the C-shaped ring, the diameter of the C-shaped ring can continuously change during the movement. At the same time, the pitch of the first sawtooth external thread is set to be greater than the pitch of the first sawtooth internal thread, which is convenient for moving and driving and will not move in the opposite direction after moving, and has good self-locking performance. Similarly, the second connecting ring 17 has a force toward the push sleeve 8 under the action of the elastic member 18, and the pitch of the second sawtooth external thread is set to be greater than the pitch of the second sawtooth internal thread, so that the sliding sleeve 16 can move smoothly toward the direction of the push sleeve 8 and will not move in the opposite direction after moving, thereby achieving self-locking.

[0058] Preferably, a second inner conical surface is provided inside the top end of the push sleeve 8, the second inner conical surface has the same taper as the second outer conical surface of the sealing sleeve 3, and the second outer conical surface can be slidably connected along the second inner conical surface and abut against the end of the second inner conical surface.

[0059] like Figure 1 and Figure 2 As shown, the top of the push sleeve 8 forms a tapered hole with the second inner conical surface. In the initial state, the sealing ring 6 and the supporting ring 7 are both sleeved on the bottom edge of the second outer conical surface and abut against the top of the push sleeve 8. After being subjected to the sealing force of the push cylinder 1, the sealing sleeve 3 moves downward and is gradually inserted into the tapered hole of the push sleeve 8. At this time, the relative movement of the push sleeve 8 and the sealing sleeve 3 causes the sealing ring 6 to be squeezed and deformed and gradually seals and abuts against the inner wall of the upper sleeve 21 until the bottom end of the sealing sleeve 3 abuts against the bottom step surface of the tapered hole. Figure 2 State shown; if the sealing sleeve 3 continues to be pushed, the push sleeve 8 will move synchronously under the action of the sealing sleeve 3, and cause the connecting rod assembly to rotate until the connecting rod assembly abuts against the inner wall of the upper sleeve 21, and the push sleeve 8 no longer moves downward. Under the action of the push sleeve 8, the sealing ring 6 moves and deforms to the first outer cone surface of the sealing sleeve 3, and has the maximum deformation sealing performance.

[0060] Preferably, the connecting rod assembly includes a first connecting rod 11 and a second connecting rod 13, one end of the first connecting rod 11 is rotatably connected to the push sleeve 8, and the other end is rotatably connected to the second connecting rod 13, and the end of the second connecting rod 13 facing away from the first connecting rod 11 is rotatably connected to the sliding sleeve 16, and pins (including a first pin 10 and a second pin 14) are respectively provided between the first connecting rod 11 and the push sleeve 8, between the first connecting rod 11 and the second connecting rod 13, and between the second connecting rod 13 and the sliding sleeve 16 for initial positioning.

[0061] like Figure 1As shown, the first connecting rod 11 is rotatably connected to the push sleeve 8 by the first cylindrical pin 9, and the relative position of the two in the initial state is locked by the first pin 10; the first connecting rod 11 and the second connecting rod 13 are rotatably connected by the second cylindrical pin 12; the second connecting rod 13 and the sliding sleeve 16 are rotatably connected by the third cylindrical pin 15, and the relative position of the two in the initial state is locked by the second pin 14. The shear force of the first pin 10 and the second pin 14 can ensure that the first connecting rod 11 and the second connecting rod 13 cannot rotate under the influence of a certain range, and the hanging card type temporary plugging tool will not be sealed in advance during the process of going down to the well. When the thrust of the push cylinder 1 is greater than the shear force of the first pin 10 and the second pin 14, the first pin 10 and the second pin 14 are sheared, and then the first connecting rod 11 and the second connecting rod 13 rotate.

[0062] In some embodiments, the bottom end of the push sleeve 8 is provided with a plurality of first mounting grooves in the circumference, and the first connecting rod 11 is rotatably connected in the first mounting groove; the top end of the sliding sleeve 16 is provided with a plurality of second mounting grooves in the circumference, and the second connecting rod 13 is rotatably connected in the second mounting groove, and the outer peripheral surface of the notch of the first mounting groove and the second mounting groove is a slope structure to facilitate the rotation avoidance of the first connecting rod 11 and the second connecting rod 13. The first pin 10 and the second pin 14 threadedly connect the first connecting rod 11 and the second connecting rod 13 in the first mounting groove and the second mounting groove. Preferably, the connecting rod assembly is provided with 4-8 groups, preferably eight groups, and the eight groups of connecting rod assemblies are evenly distributed along the axis of the pressure-bearing pipe 5 to provide a uniform circumferential force.

[0063] Preferably, the bottom end surface of the sliding sleeve 16 is provided with a plurality of mounting holes along the circumferential direction, and an elastic member 18 is provided in each mounting hole, and the two ends of the elastic member 18 respectively stop at the bottom of the mounting hole and the top end surface of the fixed sleeve 20.

[0064] like Figure 1 As shown, in this embodiment, the mounting hole is a cylindrical hole, which is evenly spaced around the axis of the sliding sleeve 16. The outer wall of the sliding sleeve 16 corresponding to the mounting hole is provided with a stepped outer cylindrical surface. The elastic member 18 is preferably a cylindrical helical compression spring. Generally, 4-12 elastic members 18 are provided. In this embodiment, eight elastic members 18 are provided. The two ends of the elastic member 18 respectively abut against the bottom of the mounting hole and the fixed sleeve 20, so as to realize the elastic abutment between the fixed sleeve 20 and the sliding sleeve 16.

[0065] Preferably, a reaming hole is provided at the top of the fixed sleeve 20 , and the sliding sleeve 16 is inserted into the reaming hole, and the axial depth of the reaming hole is greater than the elastic sliding distance of the sliding sleeve 16 .

[0066] like Figure 1The bottom end of the sliding sleeve 16 is inserted into the expanded hole of the fixed sleeve 20 and abuts against the step surface of the expanded hole to limit the position. The sliding sleeve 16 is always located in the expanded hole when it moves, that is, the axial depth of the expanded hole is greater than the rebound length of the elastic member 18. When the hanging card type temporary plugging tool slides down into the convex space, the elastic member 18 drives the sliding sleeve 16 to slide after elastic elongation and makes the second connecting rod 13 rotate twice to expand the diameter. At this time, the bottom end of the sliding sleeve 16 is always located in the expanded hole. It can be understood that the expanded hole plays a role in limiting and guiding the sliding of the sliding sleeve 16. In order to improve the connection strength of the fixed sleeve 20, a third pin 19 is provided between the fixed sleeve 20 and the pressure-bearing pipe 5 to prevent the fixed sleeve 20 from loosening. The outer peripheral wall of the bottom end of the fixed sleeve 20 is provided with a guiding inclined surface, which is conducive to the guiding role of the hanging card type temporary plugging tool when it is lowered into the casing column. A step surface is provided at the center opening of the fixing sleeve 20. After the pressure-bearing pipe 5 is threadedly connected with the fixing sleeve 20, it can stop at the step surface to limit the position, thereby avoiding damage caused by excessive connection.

[0067] The hanging card type temporary plugging tool provided in the embodiment of the present invention realizes segmented sealing or plugging of the wellbore by setting a seal, and is used to realize multi-stage segmented fracturing; after the fracturing construction is completed, the hanging card type temporary plugging tool needs to be dissolved and unsealed to restore the diameter of the wellbore.

[0068] The push tube 1 and the center joint 2 are supporting tools for the temporary plugging tool of the hanging card type, and are made of alloy steel and can be reused. The elastic member 18 is usually made of spring steel or other materials because it needs to ensure a certain elasticity and rigidity. The sealing ring 6 is made of soluble rubber material, and the sealing sleeve 3, the first connecting ring 4, the pressure-bearing pipe 5, the support ring 7 (including the Z-shaped arc segment 71); the push sleeve 8, the connecting rod assembly (including the first cylindrical pin 9, the first pin 10, the first connecting rod 11, the second cylindrical pin 12, the second connecting rod 13, the second pin 14 and the third cylindrical pin 15), the sliding sleeve 16, the second connecting ring 17, the third pin 19, the fixed sleeve 20 and the pressure ball 24 are all made of soluble metal materials, such as soluble aluminum alloy and soluble magnesium alloy, so as to ensure that the hanging card type temporary plugging tool can dissolve in the liquid with a certain temperature and mineralization at the bottom of the well after completing the temporary plugging of the casing and the staged fracturing construction (usually only the temporary plugging tool needs to be effectively plugged and work for 8-24 hours), and release the setting and plugging.

[0069] An embodiment of the present invention also provides a hanging card type temporary plugging method, which uses the hanging card type temporary plugging tool provided by the embodiment of the present invention. The hanging card type temporary plugging method is used to anchor the hanging card type temporary plugging tool in the casing column and clamp it at the coupling 22 after sliding down to achieve anti-slip positioning after sealing, thereby avoiding sealing failure.

[0070] Combination Figure 1-Figure 3 The hanging card type temporary blocking method provided by the embodiment of the present invention comprises the following steps:

[0071] S1, lower the temporary plugging tool into the upper casing 21 located above the convex space in the casing string through the push tube 1 and the center joint 2; specifically, assemble the temporary plugging tool, the push tube 1 cooperates with the first outer cylindrical surface of the sealing sleeve 3, and contacts with the step surface between the first outer cylindrical surface and the second outer cylindrical surface, the third outer conical surface and the fourth outer conical surface of the center joint 2 cooperate with the first inner conical surface and the second inner conical surface of the front end of the sealing sleeve 3 and the pressure-bearing pipe 5 respectively, and the pressure-bearing thread of the center joint 2 and the pressure-bearing pipe 5 are in place. The temporary plugging tool is lowered into the casing string above the coupling 22 near the planned fracturing position through the push tube 1 and the center joint 2.

[0072] S2, after reaching the specified position, keep the center joint 2 stationary and continue to push the push tube 1 downward. Under the thrust of the downhole tool, the sealing sleeve 3 drives the first connecting ring 4 to slide downward along the pressure pipe 5 under the action of the push tube 1. At this time, the first pin 10 and the second pin 14 between the connecting rod assembly and the push sleeve 8 and the sliding sleeve 16 are all in a locked state, that is, they are not sheared off; the sealing ring 6 is gradually deformed under the interaction of the push sleeve 8 and the sealing sleeve 3 to abut against the inner wall of the upper casing 21, and the support ring 7 moves and expands on the second outer cone surface of the sealing sleeve 3, and the second outer cone surface of the sealing sleeve 3 is gradually inserted into the tapered hole of the push sleeve 8.

[0073] S3, continue to push the push tube 1 downward, when the thrust reaches a certain value, the first pin 10 and the second pin 14 are sheared off, the connecting rod assembly between the push sleeve 8 and the sliding sleeve 16 rotates outward to expand the diameter and abuts against the inner wall of the upper casing 21 and cannot continue to rotate, the sealing ring 6 moves to between the first outer cone surface and the second outer cone surface and stops upward, and fills the annular gap between the sealing sleeve 3 and the upper casing 21 to achieve sealing, at this time the elastic member 18 is still in a compressed state; when the push tube 1 continues to be pushed, the pressure-bearing thread is sheared off, the pressure-bearing pipe 5 is separated from the center joint 2, and the push tube 1 is separated from the sealing sleeve 3, that is, the downhole tool is separated from the hanging card type temporary plugging tool.

[0074] S4, the pressure ball 24 is put in, and after the pressure ball 24 contacts the sealing sleeve 3, the hanging card type temporary plugging tool realizes the sealing of the casing string;

[0075] During the fracturing process, when the overall upper end pressure of the hanging card type temporary plugging tool is greater than the lower end pressure, the hanging card type temporary plugging tool slides down because it is not positioned until it slides to the connecting rod assembly and separates from the upper casing 21. Under the elastic abutment of the fixed sleeve 20 and the sliding sleeve 16, the connecting rod assembly rotates outward for a second time to expand its diameter until it abuts against the inner wall of the coupling 22. The hanging card type temporary plugging tool stops sliding when it slides to the end of the lower casing 23, thereby achieving sealing positioning. It can be understood that when the top end of the connecting rod assembly detaches from the bottom end of the upper sleeve 21 and enters the convex space, the limiting force of the connecting rod assembly disappears. Under the elastic force of the elastic member 18, the sliding sleeve 16 and the second connecting ring 17 have an upward force and push the second connecting rod 13 upward and rotate. When the first connecting rod 11 and the second connecting rod 13 rotate in conjunction with each other until they abut against the inner wall of the convex space (i.e., the inner wall of the coupling 22), they will continue to slide down along the inner wall of the convex space until the second connecting rod 13 contacts the top end of the lower sleeve 23. After receiving the force of the lower sleeve 23, the second connecting rod 13 tends to rotate in the opposite direction. Since the sliding sleeve 16, the second connecting ring 17 and the pressure-bearing pipe 5 are connected by a serrated thread, the position of the sliding sleeve 16 is locked and cannot slide in the opposite direction. Therefore, the connecting rod assembly will not rotate in the opposite direction, and the hanging card temporary plugging tool will no longer slide down, thereby achieving the effect of hanging card sealing positioning.

[0076] The hanging card type temporary plugging method provided by the present invention realizes that the hanging card type temporary plugging tool is finally clamped on the inner wall of the convex space through the primary rotation expansion and the secondary rotation expansion of the connecting rod assembly, and utilizes the convex space structure of the casing string to enable the connecting rod assembly to achieve anti-slip under the elastic abutment action of the sliding sleeve 16 and the fixed sleeve 20, avoiding the phenomenon of slipping and moving after setting, effectively solving the problem of setting failure, and facilitating the smooth implementation of the fracturing process.

[0077] In the above-mentioned temporary plugging method, the temporary plugging tool of the hanging card type goes through the process of lowering, loading and deformation, releasing the hand, throwing and hanging card in sequence, thereby achieving effective sealing and temporary plugging of the casing string. After the fracturing operation, the temporary plugging tool of the hanging card type can dissolve in the liquid of a certain temperature and mineralization degree at the bottom of the well by itself, and release the sealing and plugging. That is, the temporary plugging method of the hanging card type also includes the step of dissolving and unsealing the temporary plugging tool of the hanging card type after the hanging card is set, realizing the closed loop of the life cycle of the temporary plugging tool of the hanging card type.

[0078] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, various obvious changes, readjustments and substitutions can be made without departing from the protection scope of the present invention. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A temporary plugging tool with a hanging card, used for internal plugging of a casing string; characterized in that: The hanging card type temporary plugging tool comprises: A sealing sleeve (3), wherein the top end of the sealing sleeve (3) is connected to the push tube (1) on the outside and connected to the center joint (2) on the inside; A pressure-bearing pipe (5), wherein the inner side of the top end of the pressure-bearing pipe (5) is provided with a pressure-bearing thread which is threadedly connected to the center joint (2), and the outer side of the top end of the pressure-bearing pipe (5) is connected to the inner wall of the sealing sleeve (3) via a first connecting ring (4); when the push cylinder (1) pushes the sealing sleeve (3) to move relative to the center joint (2), the sealing sleeve (3) can drive the first connecting ring (4) to slide unidirectionally from the top end to the bottom end on the pressure-bearing pipe (5); A sealing ring (6), wherein the sealing ring (6) is sleeved on the outer side of the bottom end of the sealing sleeve (3); A push sleeve (8), wherein the push sleeve (8) is sleeved on the outer side of the pressure-bearing pipe (5), and the top end of the push sleeve (8) abuts against the bottom end of the sealing ring (6); when the sealing sleeve (3) slides along the pressure-bearing pipe (5), the sealing ring (6) can gradually deform to abut against the inner wall of the casing string under the interaction between the push sleeve (8) and the sealing sleeve (3); a sliding sleeve (16), the sliding sleeve (16) being sleeved on the pressure-bearing pipe (5) and connected to the pressure-bearing pipe (5) via a second connecting ring (17), the sliding sleeve (16) being able to drive the second connecting ring (17) to slide unidirectionally from the bottom end to the top end on the pressure-bearing pipe (5); A connecting rod assembly, the connecting rod assembly being arranged between the push sleeve (8) and the sliding sleeve (16), and when the push sleeve (8) and the sliding sleeve (16) have a relatively close sliding movement on the pressure-bearing pipe (5), the connecting rod assembly can rotate outward to expand the diameter and abut against the inner wall of the casing column for anchoring or hanging; A fixing sleeve (20) is threadedly connected to the bottom end of the pressure-bearing pipe (5) and elastically abuts against the bottom end of the sliding sleeve (16).

2. The hanging card type temporary plugging tool according to claim 1, characterized in that: It also comprises a support ring (7), which is sleeved on the outer side of the bottom end of the sealing sleeve (3) and abuts against the bottom end of the sealing ring (6), and the support ring (7) is formed by a plurality of Z-shaped arc segments (71) overlapping each other. When the support ring (7) is compressed, it can expand radially to support the sealing ring (6).

3. The temporary plugging tool according to claim 2, characterized in that: The outer side of the sealing sleeve (3) is provided with a first outer cylindrical surface, a second outer cylindrical surface, a first outer conical surface and a second outer conical surface in sequence from the top end to the bottom end. The outer diameter of the first outer cylindrical surface is smaller than the outer diameter of the second outer surface. A step surface is formed between the first outer cylindrical surface and the second outer cylindrical surface. The push cylinder (1) is connected to the first outer cylindrical surface and abuts against the step surface. The taper of the first outer conical surface is greater than the taper of the second outer conical surface. The sealing ring (6) and the support ring (7) are both sleeved on the second outer conical surface. When the support ring (7) and the sealing sleeve (3) slide relative to each other, the second outer conical surface causes the support ring (7) to expand radially. The top end of the inner side of the sealing sleeve (3) is provided with a first inner conical surface, and the first inner conical surface is in contact with the center joint (2).

4. The hanging card type temporary plugging tool according to claim 1, characterized in that: The inner wall and outer wall of the first connecting ring (4) are respectively provided with a first sawtooth-shaped internal thread and a first sawtooth-shaped external thread, the inner wall and outer wall of the second connecting ring (17) are respectively provided with a second sawtooth-shaped internal thread and a second sawtooth-shaped external thread, the inner wall of the bottom end of the sealing sleeve (3) is provided with a third sawtooth-shaped internal thread, the inner wall of the sliding sleeve (16) is provided with a fourth sawtooth-shaped internal thread, the pressure-bearing pipe (5) is provided with a third sawtooth-shaped external thread and a fourth sawtooth-shaped external thread, the first sawtooth-shaped internal thread and the first sawtooth-shaped external thread are respectively matched and connected with the third sawtooth-shaped external thread and the third sawtooth-shaped internal thread, so that the sealing sleeve (3) can slide unidirectionally from the top end to the bottom end along the pressure-bearing pipe (5), the second sawtooth-shaped internal thread and the second sawtooth-shaped external thread are respectively matched and connected with the fourth sawtooth-shaped external thread and the fourth sawtooth-shaped internal thread, so that the sliding sleeve (16) can slide unidirectionally from the bottom end to the top end along the pressure-bearing pipe (5).

5. The hanging card type temporary plugging tool according to claim 4, characterized in that: The first connecting ring (4) and the second connecting ring (17) are both C-shaped rings with an opening, the pitch of the first sawtooth external thread is greater than the pitch of the first sawtooth internal thread, and the pitch of the second sawtooth external thread is greater than the pitch of the second sawtooth internal thread.

6. The hanging card type temporary plugging tool according to claim 1, characterized in that: A second inner conical surface is provided inside the top end of the push sleeve (8), the second inner conical surface has the same taper as the second outer conical surface of the sealing sleeve (3), and the second outer conical surface can be slidably connected along the second inner conical surface and then abut against the end of the second inner conical surface.

7. The hanging card type temporary plugging tool according to claim 1, characterized in that: The connecting rod assembly comprises a first connecting rod (11) and a second connecting rod (13), one end of the first connecting rod (11) is rotatably connected to the push sleeve (8), and the other end is rotatably connected to the second connecting rod (13), and one end of the second connecting rod (13) facing away from the first connecting rod (11) is rotatably connected to the sliding sleeve (16), and pins are provided between the first connecting rod (11) and the push sleeve (8), and between the second connecting rod (13) and the sliding sleeve (16) for initial positioning.

8. The hanging card type temporary plugging tool according to claim 1, characterized in that: The bottom end surface of the sliding sleeve (16) is provided with a plurality of mounting holes along the circumferential direction, each mounting hole is provided with an elastic member (18), and the two ends of the elastic member (18) respectively abut against the bottom of the mounting hole and the fixing sleeve (20).

9. The hanging card type temporary plugging tool according to claim 1, characterized in that: The top end of the fixed sleeve (20) is provided with an expanded hole, the sliding sleeve (16) is inserted into the expanded hole, and the axial depth of the expanded hole is greater than the elastic sliding distance of the sliding sleeve (16).

10. The hanging card type temporary plugging tool according to claim 2, characterized in that: The sealing sleeve (3), the first connecting ring (4), the pressure-bearing pipe (5), the supporting ring (7), the push sleeve (8), the sliding sleeve (16), the connecting rod assembly and the fixing sleeve (20) are all made of soluble metal materials, the sealing ring (6) is made of soluble rubber material, and the hanging card type temporary plugging tool can be dissolved underground to release the seal.

11. The temporary blocking method of hanging card is characterized by: Using the hanging card type temporary plugging tool according to any one of claims 1 to 10, the hanging card type temporary plugging method comprises the following steps: The hanging card type temporary plugging tool is lowered into the casing column and into the upper casing (21) located above the convex space through the push cylinder (1) and the center joint (2); The central joint (2) is kept stationary, and the push tube (1) is continuously pushed downward. The sealing sleeve (3) drives the first connecting ring (4) to slide downward along the pressure-bearing pipe (5) under the action of the push tube (1). The sealing ring (6) is gradually deformed to abut against the inner wall of the upper sleeve (21) under the interaction between the push sleeve (8) and the sealing sleeve (3); The push cylinder (1) is continuously pushed downward, the connecting rod assembly between the push sleeve (8) and the sliding sleeve (16) rotates outward once to expand the diameter and abuts against the inner wall of the upper sleeve (21), the pressure-bearing pipe (5) is separated from the center joint (2), and the push cylinder (1) is separated from the sealing sleeve (3); A pressure ball (24) is placed, and after the pressure ball (24) contacts the sealing sleeve (3), the hanging card type temporary plugging tool realizes the sealing of the casing column; When the pressure at the upper end of the entire hanging card type temporary plugging tool is greater than the pressure at the lower end, the hanging card type temporary plugging tool slides down until the connecting rod assembly is separated from the upper casing (21). Under the elastic abutment of the fixed sleeve (20) and the sliding sleeve (16), the connecting rod assembly rotates outward for a second time to expand its diameter until it abuts against the inner wall of the coupling (22). When the hanging card type temporary plugging tool slides down to the end of the lower casing (23), it stops sliding down, thereby achieving hanging card anti-slip.

12. The hanging card type temporary blocking method according to claim 11, characterized in that: The method also includes the steps of releasing the stuck and sealing the temporary plugging tool: after the fracturing operation is completed, the temporary plugging tool dissolves itself under specific temperature and mineralization conditions underground to release the stuck and seal, and restore the diameter of the casing string.

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