A downhole seal hanger and its use method

Abstract

The present invention discloses a downhole sealing hanger and a method for using the same, and belongs to the technical field of downhole operations. The hanger mechanism is used for sealing downhole pipelines. The sealing mechanism is connected to the hanger mechanism and is used to push the hanger mechanism for sealing. The hanger mechanism includes an upper push tube, a locking ring, a locking outer tube, an integral rubber tube, a lower stopper, an upper cone, a limiting ring, a slip sleeve, a slip, a lower cone, a lower connecting sleeve, a lower joint, an unblocking and fixing ring, an unsealing ring and a central axis A. The unsealing parts of the present invention are made of soluble materials, and the unsealing time can be adjusted according to the usage conditions to realize the automatic unsealing function of the tool.

Description

Technical Field

[0001] The invention belongs to the technical field of downhole operations, and in particular relates to a downhole sealing hanger and a use method thereof. Background Art

[0002] At present, traditional hangers on the market generally use hydraulic tools or mechanical shock sealing methods, and most of the sealing tools are special tools with complex structures and high costs. Special unsealing tools are also required for unsealing.

[0003] A downhole seal hanger is now proposed which can be unsealed without an unsealing tool. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present invention provides a downhole seal hanger and a method of using the same, which solves the above-mentioned problems.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solutions: A downhole seal hanger comprises:

[0006] The hanger mechanism is used to seal the downhole pipeline;

[0007] A sealing mechanism is connected to the hanger mechanism and is used to push the hanger mechanism to perform a sealing process;

[0008] Wherein, the hanger mechanism includes an upper push tube, a locking ring, a locking outer tube, an integral rubber tube, a lower stopper, an upper cone, a limiting ring, a slip sleeve, a slip, a lower cone, a lower connecting sleeve, a lower joint, an unblocking limiting ring, an unblocking ring and a center axis A. The upper push tube is detachably connected to the locking outer tube by a bolt A, and the locking ring is threadedly connected to the center axis A and the locking outer tube by a thread. The upper push tube is installed at the end of the center axis A, and the integral rubber tube is installed on the center axis A and abuts against one end of the locking outer tube. The upper cone connected with the lower stopper is detachably connected to the center axis A by a bolt B, and the limiting ring is embedded and installed on the center axis A and Located inside the upper cone, the cava sleeve connected with the cava is installed on the cone of the upper cone, the cava sleeve is arranged on the central axis A, the lower cone and the lower connecting sleeve are both arranged on the central axis A, one end of the lower cone extends into the lower connecting sleeve, the lower joint is detachably connected to the lower connecting sleeve by a thread, the unlocking and locking ring is detachably connected to the central axis A by a thread, the unlocking and locking ring is located in the cavity A formed by the unlocking ring and the lower connecting sleeve, the unlocking ring is installed on the central axis A and is located in the cavity B formed by the lower connecting sleeve, the lower joint, the unlocking and locking ring and the central axis A, and the upper push cylinder is detachably connected to the seat sealing mechanism.

[0009] On the basis of the above technical solution, the present invention also provides the following optional technical solution:

[0010] Further technical solution: the upper push cylinder, locking ring, locking outer cylinder, integral rubber cylinder, lower stopper, upper cone, slip, lower cone, lower connecting sleeve, and lower joint are linearly arranged in sequence along the length direction of the central axis A.

[0011] Further technical solution: the locking ring and the unlocking ring are both made of aluminum-magnesium alloy material.

[0012] Further technical solution: The locking outer cylinder, the lower joint and the unsealing ring are all provided with through holes for liquid to flow in.

[0013] Further technical solution: The sealing mechanism includes an upper joint, an outer sleeve, a backup battery, a center axis B, a motor drive board, a main control board, an oil pump motor, a hydraulic joint, a hydraulic outer cylinder, a sealing push cylinder and a fixed lock nut. The sealing push cylinder is threadedly connected to the upper push cylinder, the upper joint is detachably connected to the center axis B through a thread, the outer sleeve is detachably connected to the upper joint through a thread, the backup battery is detachably connected to the center axis B through a bolt C, the oil pump motor is detachably connected to the center axis B through a bolt D, the hydraulic joint is threadedly connected to the outer sleeve, the hydraulic outer cylinder is threadedly connected to the hydraulic joint, the sealing push cylinder mounted on the hydraulic joint is located in the hydraulic outer cylinder and slides relative to the hydraulic joint and the hydraulic outer cylinder, and the fixed lock nut is threadedly connected to the hydraulic joint and slides with the sealing push cylinder.

[0014] The method for using the downhole seal hanger comprises the following steps:

[0015] S1, powered by cables or backup batteries, the main control board controls the rotation of the oil pump motor through the motor drive board, the oil pump motor outputs oil and flows into one side of the hydraulic outer cylinder through the oil channel opened on the hydraulic joint, the oil pump motor continuously outputs oil, the oil pressure increases, and the hydraulic outer cylinder is pushed to move linearly along the length direction of the hydraulic joint, and then the push cylinder of the hydraulic joint threadedly connected thereto is pushed to move linearly;

[0016] S2, the upper push tube drives the locking ring to perform linear motion and squeezes the integral rubber tube, the integral rubber tube pushes the lower block and the upper cone to perform linear motion, and the upper cone pushes the slips to perform seat sealing on the downhole pipeline;

[0017] S3. The information acquisition unit obtains the oil pressure information of the hydraulic outer cylinder that pushes the seat seal push cylinder to perform linear movement and the displacement information of the seat seal push cylinder to perform linear movement. The information processing unit compares the obtained oil pressure information and linear displacement information with the preset pressure threshold and displacement threshold. If any one of the two is within the corresponding threshold, it indicates that the upper push cylinder has initially moved to the preset position to perform seat sealing treatment on the downhole casing. The oil pump motor is continuously started to make the hydraulic pressure information and displacement information within the corresponding threshold. At the same time, the obtained hydraulic pressure information and displacement information are dimensionlessly processed and introduced into the movement evaluation model to obtain the movement evaluation coefficient. The obtained movement evaluation coefficient is compared with the movement evaluation coefficient threshold. If the obtained movement evaluation coefficient is outside the movement evaluation coefficient threshold, control information is formed. At this time, the control unit starts the oil pump motor and adjusts the hydraulic pressure information and displacement information until the movement evaluation coefficient is within the movement evaluation coefficient threshold, thereby completing the seat sealing treatment of the downhole pipeline.

[0018] S4: After the preset sealing time is reached, the unsealing ring dissolves automatically under the action of the underground high temperature. At this time, the central axis A is lifted up to complete the unsealing process.

[0019] Further technical solution: The mobile evaluation model is expressed as:

[0020]

[0021] in, represents the mobile evaluation coefficient, Indicates hydraulic pressure information, Indicates displacement information, Indicates the influence factor of hydraulic pressure information on the sealing tightness of the seat seal, Indicates the influence factor of displacement information on the sealing tightness of the seat seal, Indicates the influence factor of temperature on hydraulic pressure information.

[0022] The present invention provides a downhole seal hanger and a method for using the same, which have the following beneficial effects compared with the prior art:

[0023] 1. In the present invention, the sealing mechanism pushes the upper push cylinder, the upper push cylinder drives the locking ring to perform linear motion and squeeze the integral rubber cylinder, the integral rubber cylinder pushes the lower block and the upper cone to perform linear motion, the upper cone pushes the slip to complete the sealing process of the underground pipeline, according to the use requirements, after waiting for a certain period of time, the locking ring and the unlocking ring dissolve by themselves under the action of the underground high temperature and chloride ion salt solution, at this time, the central axis A is lifted up, and the hanger completes the unsealing process;

[0024] 2. The present invention adopts an electrically controlled sealing tool for sealing. After the tool string is sent into the well, the electrically controlled tool is used for sealing directly. There is no need to use a ball-throwing or shock-type sealing method, which reduces operation time and cost. Compared with traditional tools, it reduces material usage. At the same time, the unsealing parts are made of soluble materials, and the unsealing time can be adjusted according to the usage conditions to realize the automatic unsealing function of the tool. There is no need to equip the unsealing tool separately. The overall structure of the tool is simple and easy to operate, which reduces the requirements for operators, reduces operation time, and reduces operation costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a structural schematic diagram of the hanger mechanism of the present invention.

[0026] Figure 2 It is a structural schematic diagram of the sealing mechanism of the present invention.

[0027] Notes on the accompanying drawings: 1. Upper push cylinder; 2. Locking ring; 3. Locking outer cylinder; 4. Integral rubber cylinder; 5. Lower stopper; 6. Upper cone; 7. Limiting ring; 8. Slip sleeve; 9. Slip; 10. Lower cone; 11. Lower connecting sleeve; 12. Lower joint; 13. Unlocking locking ring; 14. Unlocking ring; 15. Center axis A; 16. Upper joint; 17. Outer sleeve; 18. Spare battery; 19. Center axis B; 20. Motor drive board; 21. Main control board; 22. Oil pump motor; 23. Hydraulic joint; 24. Hydraulic outer cylinder; 25. Sealing push cylinder; 26. Fixed lock nut. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0029] The specific implementation of the present invention is described in detail below in conjunction with specific embodiments.

[0030] See also Figure 1 , provided in one embodiment of the present invention, is a downhole seal hanger, comprising:

[0031] The hanger mechanism is used to seal the downhole pipeline;

[0032] A sealing mechanism is connected to the hanger mechanism and is used to push the hanger mechanism to perform a sealing process;

[0033] Wherein, the hanger mechanism includes an upper push tube 1, a locking ring 2, a locking outer tube 3, an integral rubber tube 4, a lower stopper 5, an upper cone 6, a limiting ring 7, a slip sleeve 8, a slip 9, a lower cone 10, a lower connecting sleeve 11, a lower joint 12, an unlocking and locking ring 13, an unlocking ring 14 and a center axis A15. The upper push tube 1 is detachably connected to the locking outer tube 3 by a bolt A, the locking ring 2 is threadedly connected to the center axis A15 and the locking outer tube 3 by a thread, the upper push tube 1 is installed at the end of the center axis A15, the integral rubber tube 4 is installed on the center axis A15 and abuts against one end of the locking outer tube 3, the upper cone 6 connected with the lower stopper 5 is detachably connected to the center axis A15 by a bolt B, and the limiting ring 7 is embedded and installed on the center axis A15 and is located at the upper cone 6, the cava sleeve 8 connected with the cava 9 is installed on the cone of the upper cone 6, the cava 9 is sleeved on the central axis A15, the lower cone 10 and the lower connecting sleeve 11 are both sleeved on the central axis A15, one end of the lower cone 10 extends into the lower connecting sleeve 11, the lower joint 12 is detachably connected to the lower connecting sleeve 11 through a thread, the unlocking and locking ring 13 is detachably connected to the central axis A15 through a thread, the unlocking and locking ring 13 is located in the cavity A formed by the unlocking ring 14 and the lower connecting sleeve 11, the unlocking ring 14 is installed on the central axis A15 and is located in the cavity B (not marked in the figure) formed by the lower connecting sleeve 11, the lower joint 12, the unlocking and locking ring 13 and the central axis A15, and the upper push cylinder 1 is detachably connected to the seat sealing mechanism.

[0034] Preferably, the upper push cylinder 1, locking ring 2, locking outer cylinder 3, integral rubber cylinder 4, lower stopper 5, upper cone 6, slip 9, lower cone 10, lower connecting sleeve 11, and lower joint 12 are linearly arranged in sequence along the length direction of the central axis A15.

[0035] Preferably, the unsealing ring 14 is sleeved on the central axis A15 and is locked and prevented from retreating by means of a geometric structure.

[0036] Preferably, the locking ring 2 and the unlocking ring 13 are both made of aluminum-magnesium alloy. Since the locking ring 2 and the unlocking ring 13 are made of aluminum-magnesium alloy, and aluminum-magnesium alloy is a soluble metal, when chloride ion-containing salts are added and the high temperature is applied underground, the chloride ion-containing salts react chemically with the soluble metals, and the aluminum-magnesium alloy will dissolve (chloride ions have good penetrability and will destroy the oxide film on the surface of the material, and magnesium ions are highly active and will produce galvanic corrosion, thereby achieving a dissolution effect). The chloride ion salt solution is a potassium chloride solution.

[0037] Preferably, the locking outer cylinder 3, the lower joint 12 and the unsealing ring 14 are all provided with through holes for liquid to flow in.

[0038] In the embodiment of the present invention, the sealing mechanism pushes the upper push cylinder 1, the upper push cylinder 1 drives the locking ring 2 to perform linear movement and squeezes the integral rubber cylinder 4, the integral rubber cylinder 4 pushes the lower block 5 and the upper cone 6 to perform linear movement, and the upper cone 6 pushes the cava 9 to complete the sealing process of the downhole pipeline. According to the use requirements, after waiting for a certain period of time, the locking ring 2 and the unlocking ring 13 dissolve by themselves under the action of the high temperature and chloride ion salts in the well. At this time, the center axis A15 is lifted up to complete the unsealing process.

[0039] See also Figure 2 As an embodiment of the present invention, the sealing mechanism includes an upper joint 16, an outer sleeve 17, a backup battery 18, a central axis B19, a motor drive board 20, a main control board 21, an oil pump motor 22, a hydraulic joint 23, a hydraulic outer cylinder 24, a sealing push cylinder 25 and a fixed lock nut 26. The sealing push cylinder 25 is threadedly connected to the upper push cylinder 1, the upper joint 16 is detachably connected to the central axis B19 through a thread, the outer sleeve 17 is detachably connected to the upper joint 16 through a thread, and the backup battery The tank 18 is detachably connected to the center axis B19 by a bolt C, the oil pump motor 22 is detachably connected to the center axis B19 by a bolt D, the hydraulic joint 23 is threadedly connected to the outer sleeve 17, the hydraulic outer cylinder 24 is threadedly connected to the hydraulic joint 23, the seat seal push cylinder 25 sleeved on the hydraulic joint 23 is located in the hydraulic outer cylinder 24 and slides relative to the hydraulic joint 23 and the hydraulic outer cylinder 24, and the fixed lock nut 26 is threadedly connected to the hydraulic joint 23 and slides with the seat seal push cylinder 25.

[0040] In the embodiment of the present invention, the cable or backup battery 18 is used for power supply, and the main control board controls the rotation of the oil pump motor 22 through the motor drive board 20. The oil pump motor 22 outputs oil and flows into one side of the hydraulic outer cylinder 24 through the oil channel opened on the hydraulic joint 23. The oil pump motor 22 continuously outputs oil, and the oil pressure increases, which pushes the hydraulic outer cylinder 24 to move linearly along the length direction of the hydraulic joint 23, and then pushes the push cylinder 1 on the hydraulic joint 23 threadedly connected thereto to move linearly, thereby realizing the sealing treatment of the downhole casing.

[0041] As an embodiment of the present invention, a control system for accurately controlling the moving position of the upper push tube 1 is also included. The control system includes an information acquisition unit, an information processing unit and a control unit. The working principle of the control system is as follows:

[0042] The information acquisition unit is used to obtain the oil pressure information of the hydraulic outer cylinder 24 that pushes the seat seal push cylinder 25 to perform linear motion and the displacement information of the seat seal push cylinder 25 to perform linear motion;

[0043] The information processing unit compares the acquired oil pressure information and linear displacement information with the preset pressure threshold and displacement threshold. If either of the two is within the corresponding threshold, it indicates that the push tube 1 has preliminarily moved to the preset position to perform a seating process on the downhole casing.

[0044] The oil pump motor 22 is continuously started to make the hydraulic pressure information and the displacement information within the corresponding thresholds. At the same time, the obtained hydraulic pressure information and the displacement information are dimensionlessly processed and introduced into the movement evaluation model to obtain the movement evaluation coefficient. The obtained movement evaluation coefficient is compared with the movement evaluation coefficient threshold. If the obtained movement evaluation coefficient is outside the movement evaluation coefficient threshold, control information is formed. At this time, the control unit starts the oil pump motor 22 and adjusts the hydraulic pressure information and the displacement information until the movement evaluation coefficient is within the movement evaluation coefficient threshold. The movement evaluation model is expressed as:

[0045]

[0046] in, represents the mobile evaluation coefficient, Indicates hydraulic pressure information, Indicates displacement information, Indicates the influence factor of hydraulic pressure information on the sealing tightness of the seat seal, Indicates the influence factor of displacement information on the sealing tightness of the seat seal, Indicates the influence factor of temperature on hydraulic pressure information.

[0047] Among them, the influence factors of hydraulic pressure information on the sealing degree of the seat seal, the influence factors of displacement information on the sealing degree of the seat seal, and the influence factors of temperature on the hydraulic pressure information can be obtained through multiple linear regression analysis using SPSS software.

[0048] A method for using a downhole seal hanger comprises the following steps:

[0049] S1, the cable or the backup battery 18 is powered, the main control board controls the oil pump motor 22 to rotate through the motor drive board 20, the oil pump motor 22 outputs oil and flows into one side of the hydraulic outer cylinder 24 through the oil channel opened on the hydraulic joint 23, the oil pump motor 22 continuously outputs oil, the oil pressure increases, and the hydraulic outer cylinder 24 is pushed along the length direction of the hydraulic joint 23 to perform linear motion, and then the push cylinder 1 on the hydraulic joint 23 threadedly connected thereto is pushed to perform linear motion;

[0050] S2, the upper push tube 1 drives the locking ring 2 to perform linear motion and squeezes the integral rubber tube 4, the integral rubber tube 4 pushes the lower block 5 and the upper cone 6 to perform linear motion, and the upper cone 6 pushes the slip 9 to perform seat sealing on the downhole pipeline;

[0051] S3. The information acquisition unit obtains the oil pressure information and displacement information of the linear movement of the sealing push tube 25 in the hydraulic outer tube 24, and the information processing unit compares the obtained oil pressure information and linear displacement information with the preset pressure threshold and displacement threshold. If any one of the two is within the corresponding threshold, it indicates that the upper push tube 1 has initially moved to the preset position to perform a sealing process on the downhole casing. The oil pump motor 22 is continuously started to cause the hydraulic pressure information and displacement information to be within the corresponding threshold. At the same time, the obtained hydraulic pressure information and displacement information are dimensionlessly processed and introduced into the movement evaluation model to obtain the movement evaluation coefficient. The obtained movement evaluation coefficient is compared with the movement evaluation coefficient threshold. If the obtained movement evaluation coefficient is outside the movement evaluation coefficient threshold, control information is formed. At this time, the control unit starts the oil pump motor 22 to adjust the hydraulic pressure information and displacement information until the movement evaluation coefficient is within the movement evaluation coefficient threshold, and the downhole pipeline is sealed.

[0052] S4, after reaching the preset sealing time, the locking ring 2 and the unlocking ring 13 are dissolved by themselves under the action of the underground high temperature and the chloride ion salt solution, and the central axis A15 is lifted up at this time to complete the unlocking process.

[0053] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0054] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A downhole seal hanger, characterized in that: include: The hanger mechanism is used to seal the downhole pipeline; A sealing mechanism is connected to the hanger mechanism and is used to push the hanger mechanism to perform a sealing process; The hanger mechanism comprises an upper push tube (1), a locking ring (2), a locking outer tube (3), an integral rubber tube (4), a lower stopper (5), an upper cone (6), a limiting ring (7), a slip sleeve (8), a slip (9), a lower cone (10), a lower connecting sleeve (11), a lower joint (12), an unlocking and fixing ring (13), an unlocking ring (14) and a central axis A (15). The upper push tube (1) is connected to the locking outer tube (3) by a bolt A, and the locking ring (2) is connected to the central axis by a thread. A (15) and a locking outer cylinder (3) are threadedly connected, the upper push cylinder (1) is installed at the end of the central axis A (15), the integral rubber cylinder (4) is installed on the central axis A (15) and contacts one end of the locking outer cylinder (3), the upper cone (6) connected to the lower stopper (5) is connected to the central axis A (15) by a bolt B, the limit ring (7) is embedded and installed on the central axis A (15) and is located on the inner side of the upper cone (6), and the slip sleeve (8) connected to the slip (9) is installed on the upper cone (6) The slip (9) is sleeved on the central axis A (15), the lower cone (10) and the lower connecting sleeve (11) are both sleeved on the central axis A (15), one end of the lower cone (10) extends into the lower connecting sleeve (11), the lower joint (12) is connected to the lower connecting sleeve (11) by a thread, the unlocking and locking ring (13) is connected to the central axis A (15) by a thread, and the unlocking and locking ring (13) is located in the cavity A formed by the unlocking ring (14) and the lower connecting sleeve (11). The unlocking ring (14) is installed on the central axis A (15) and is located in a cavity B formed by the lower connecting sleeve (11), the lower joint (12), the unlocking locking ring (13) and the central axis A (15). The upper push cylinder (1) is connected to the seat sealing mechanism. The locking ring (2) and the unlocking locking ring (13) are both made of aluminum-magnesium alloy material. Aluminum-magnesium alloy is a soluble metal. When salts containing chloride ions are added and the underground high temperature is applied, the salts containing chloride ions react chemically with the soluble metal, and the aluminum-magnesium alloy is dissolved.

2. The downhole seal hanger according to claim 1, characterized in that: The upper push cylinder (1), the locking ring (2), the locking outer cylinder (3), the integral rubber cylinder (4), the lower stopper (5), the upper cone (6), the slip (9), the lower cone (10), the lower connecting sleeve (11), and the lower joint (12) are linearly arranged in sequence along the length direction of the central axis A (15).

3. The downhole seal hanger according to claim 2, characterized in that: The locking outer cylinder (3), the lower joint (12) and the unsealing ring (14) are all provided with through holes for liquid to flow in.

4. The downhole seal hanger according to claim 1, characterized in that: The sealing mechanism comprises an upper joint (16), an outer sleeve (17), a backup battery (18), a central axis B (19), a motor drive board (20), a main control board (21), an oil pump motor (22), a hydraulic joint (23), a hydraulic outer sleeve (24), a sealing push sleeve (25) and a fixing lock nut (26), wherein the sealing push sleeve (25) is threadedly connected to the upper push sleeve (1), the upper joint (16) is threadedly connected to the central axis B (19), the outer sleeve (17) is threadedly connected to the upper joint (16), the backup battery (18) is threadedly connected to the central axis B (19), the outer sleeve (17) is threadedly connected to the upper joint (16), and the backup battery (18) is threadedly connected to the central axis B (19). The hydraulic joint (23) is connected to the outer sleeve (17) by a threaded connection, and the hydraulic outer sleeve (24) is threadedly connected to the hydraulic joint (23). The seat seal push cylinder (25) sleeved on the hydraulic joint (23) is located in the hydraulic outer sleeve (24) and is slidably matched with the hydraulic joint (23) and the hydraulic outer sleeve (24). The fixed lock nut (26) is threadedly connected to the hydraulic joint (23) and is slidably matched with the seat seal push cylinder (25).

5. A method for using the downhole seal hanger according to claim 4, characterized in that: The following steps are involved: S1, cable or backup battery (18) is used for power supply, the main control board controls the oil pump motor (22) to rotate through the motor drive board (20), the oil pump motor (22) outputs oil and flows into one side of the hydraulic outer cylinder (24) through the oil channel opened on the hydraulic joint (23), the oil pump motor (22) continuously outputs oil, the oil pressure increases, and the hydraulic outer cylinder (24) is pushed to perform linear movement along the length direction of the hydraulic joint (23), thereby pushing the upper push cylinder (1) of the hydraulic joint (23) threadedly connected thereto to perform linear movement; S2, the upper push tube (1) drives the locking ring (2) to perform linear movement and squeezes the integral rubber tube (4), the integral rubber tube (4) pushes the lower stopper (5) and the upper cone (6) to perform linear movement, and the upper cone (6) pushes the slip (9) to perform a seat sealing treatment on the downhole pipeline; S3, obtaining, through the information acquisition unit, the oil pressure information of the hydraulic outer cylinder (24) that pushes the sealing push cylinder (25) to perform linear movement and the displacement information of the sealing push cylinder (25) to perform linear movement, the information processing unit compares the obtained oil pressure information and linear displacement information with the preset pressure threshold and displacement threshold, if either of the two is within the corresponding threshold, it indicates that the upper push cylinder (1) has initially moved to the preset position to perform a sealing process on the downhole casing, the oil pump motor (22) is continuously started to cause the hydraulic pressure information and displacement information to be within the corresponding threshold, and at the same time, the obtained hydraulic pressure information and displacement information are dimensionlessly processed and introduced into the movement evaluation model to obtain a movement evaluation coefficient, and the obtained movement evaluation coefficient is compared with the movement evaluation coefficient threshold, if the obtained movement evaluation coefficient is outside the movement evaluation coefficient threshold, then control information is formed, and at this time the control unit starts the oil pump motor (22) to adjust the hydraulic pressure information and displacement information until the movement evaluation coefficient is within the movement evaluation coefficient threshold, thereby completing the sealing process on the downhole pipeline; S4. After the preset sealing time is reached, the locking ring (2) and the unlocking ring (13) are dissolved by themselves under the action of the underground high temperature and chloride ion-containing salts. At this time, the central axis A (15) is lifted up to complete the unlocking process.

6. The method for using a downhole seal hanger according to claim 5, characterized in that: The mobile evaluation model is expressed as: in, represents the mobile evaluation coefficient, Indicates hydraulic pressure information, Indicates displacement information, Indicates the influence factor of hydraulic pressure information on the sealing tightness of the seat seal, Indicates the influence factor of displacement information on the sealing tightness of the seat seal, Indicates the influence factor of temperature on hydraulic pressure information.

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