Long well section casing damage well patching device and patching method

Abstract

The invention belongs to the technical field of well repair, and discloses a long well section casing damage well patching device and patching method.The device comprises an upper expansion pipe, a lower expansion pipe, a connecting casing pipe and an expansion assembly; the connecting sleeves are connected in sequence, the connecting sleeve located at the head end is connected to one end of the upper expansion pipe, and the connecting sleeve located at the tail end is connected to the open end of the lower expansion pipe; the expansion assembly comprises a center pipe, a first expansion cone and a second expansion cone, the first expansion cone is located in the lower expansion pipe, the second expansion cone is arranged in the upper expansion pipe, the center pipe is provided with an abutting part, the abutting part is located between the first expansion cone and the second expansion cone, and the abutting part and the second expansion cone can be clamped in a limiting mode. According to the long-well-section casing damage well patching method, the long-well-section casing damage well patching device is adopted, the two ends are plugged through expansion, the multiple connecting sleeves are adopted in the middle for connection, accurate and specific leakage positions are not needed, the construction efficiency is high, and adaptability is high.

Description

Technical Field

[0001] The present invention relates to the technical field of well repair, and in particular to a long well section casing damage well repair device and repair method. Background Art

[0002] With the increasing number of old wells, casing damage conditions are becoming increasingly complex, such as corrosion and leakage in long well sections, perforation layer adjustment and plugging, etc. The current conventional treatment methods for this well condition include chemical plugging and small-section expansion tube patching technology; however, chemical plugging has low construction efficiency and requires multiple injections and pressure holding. At the same time, the plugging time is short, it is easy to fail, and the cost is high; while the small-section expansion tube patching technology adopts the expansion tube patching technology, that is, a section of pipe with good ductility is lowered into the damaged oil and gas well casing. After reaching the expected well depth, the expansion cone is driven by high-pressure working fluid to expand the pipe beyond the elastic limit and plastically deform, so that the pipe with the predetermined inner and outer diameters is tightly attached to the outer casing, thereby realizing the repair and patching of the casing damaged well; there may be multiple corrosion and leakage locations in the long well section, and the small-section expansion tube patching requires precise determination of the leakage location, so the technical construction efficiency is low and the cost is high. Summary of the invention

[0003] The purpose of the present invention is to provide a long well section casing damage well repair device and repair method, which adopts expansion plugging at both ends and multiple connecting casings in the middle for connection, does not require precise and specific leakage locations, has high construction efficiency and strong adaptability.

[0004] To achieve this object, the present invention adopts the following technical solutions:

[0005] A long well casing damage well compensation device comprises an upper expansion pipe and a lower expansion pipe, one end of the lower expansion pipe is open, and further comprises:

[0006] A connecting sleeve, wherein a plurality of the connecting sleeves are connected in sequence, the connecting sleeve at the head end is connected to one end of the upper expansion pipe, and the connecting sleeve at the tail end is connected to the open end of the lower expansion pipe;

[0007] An expansion assembly, the expansion assembly includes a center tube, a first expansion cone and a second expansion cone, the first expansion cone is located in the lower expansion tube, the second expansion cone is arranged in the upper expansion tube, the center tube moves through the inner cavity of the second expansion cone and connects the first expansion cone to form a through channel with the inner cavity of the first expansion cone; the center tube is provided with a stop top, the stop top is located between the first expansion cone and the second expansion cone, and the stop top can be limitedly engaged with the second expansion cone.

[0008] Preferably, the center tube includes a first tube and a second tube, the first end of the first tube is connected to the first expansion cone, the second end of the first tube is provided with the abutment top, the abutment top is provided with an inner cavity, the second tube is passed through the inner cavity of the second expansion cone, and can be detachably inserted into the inner cavity of the abutment top.

[0009] Preferably, the inner cavity wall of the second expansion cone is provided with a first abutting surface, and the outer wall of the abutting top is provided with a second abutting top surface matching with the first abutting top surface.

[0010] Preferably, a plurality of first sealing members distributed axially along the center tube are sleeved on the outer side of the abutment top.

[0011] Preferably, a second sealing member is circumferentially provided on the outer surface of the first expansion cone.

[0012] Preferably, a third sealing member is circumferentially provided on the outer surface of the second expansion cone, and the second expansion cone and the upper expansion tube tightly clamp the third sealing member so that the two are relatively still in the absence of external force.

[0013] Preferably, the diameters of the upper expansion tube, the connecting sleeve and the lower expansion tube decrease in sequence.

[0014] Preferably, the connecting sleeve is threadedly connected to the upper expansion tube; adjacent connecting sleeves are threadedly connected to each other; and the connecting sleeve is threadedly connected to the lower expansion tube.

[0015] Preferably, the outer walls of the upper expansion tube and the lower expansion tube are circumferentially provided with expansion seals, and a plurality of the expansion seals are distributed at intervals along the axial direction of the upper expansion tube and the lower expansion tube.

[0016] A method for compensating a well with casing damage in a long well section is also provided, which uses the long well section casing damage compensating device as described above and comprises the following steps:

[0017] The number and length of the required connecting casings are determined according to the repair length of the long well section, and together with the expansion assembly, the upper expansion pipe and the lower expansion pipe, the long well section casing damage repair device is formed;

[0018] Delivering the long well section casing damage compensation device to a designated well depth;

[0019] Inject pressure liquid through the central tube to push the first expansion cone up and through the lower expansion tube to expand the lower expansion tube; when the top is engaged with the second expansion cone, continue to inject pressure liquid to push the second expansion cone through the upper expansion tube until the second expansion cone is completely passed.

[0020] Beneficial effects of the present invention:

[0021] By arranging an upper expansion pipe and a lower expansion pipe at the front and rear ends of the leakage position and connecting them in the middle through a connecting sleeve, the front and rear ends of the leakage position can be directly blocked, thereby eliminating the need to accurately determine the leakage position, saving construction time and improving construction efficiency; in addition, the expansion assembly uses a first expansion cone and a second expansion cone to expand, subsidize and block the upper expansion pipe and the lower expansion pipe respectively, avoiding the use of one expansion cone during the subsidizing process of a long well section, avoiding excessive travel of the expansion cone, resulting in excessive wear of the expansion cone, causing failure of the expansion cone, and making it impossible to perform subsidizing. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a cross-sectional view of a long well section casing damage well compensation device of the present invention;

[0023] Figure 2 It is a partial cross-sectional view of the expansion assembly in the long well section casing damage well repair device of the present invention;

[0024] Figure 3 It is a cross-sectional view of the limiting engagement between the abutment top and the second expansion cone in the long well section casing damage repair device of the present invention.

[0025] In the figure:

[0026] 1. Upper expansion tube; 2. Lower expansion tube; 3. Connecting sleeve; 4. Sealing piece; 5. Expansion assembly; 51. Center tube; 511. First tube; 512. Second tube; 52. First expansion cone; 53. Second expansion cone; 54. Top end; 55. First sealing piece; 6. Expansion sealing piece. DETAILED DESCRIPTION

[0027] 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.

[0028] 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.

[0029] 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.

[0030] In the description of this embodiment, the terms "upper", "lower", "left", "right" and other 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 operate 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.

[0031] like Figures 1 to 3 As shown, the present application provides a long well section casing damage well repair device, the device includes an upper expansion pipe 1 and a lower expansion pipe 2, one end of the lower expansion pipe 2 is open, the device also includes a connecting sleeve 3 and an expansion assembly 5; wherein, multiple connecting sleeves 3 are connected in sequence, the connecting sleeve 3 located at the head end is connected to one end of the upper expansion pipe 1, and the connecting sleeve 3 located at the tail end is connected to the open end of the lower expansion pipe 2; the expansion assembly 5 includes a center pipe 51, a first expansion cone 52 and a second expansion cone 53, the first expansion cone 52 is located in the lower expansion pipe 2, and the second expansion cone 53 is arranged in the upper expansion pipe 1, the center pipe 51 moves through the inner cavity of the second expansion cone 53 and connects the first expansion cone 52 to form a through channel with the inner cavity of the first expansion cone 52; the center pipe 51 is provided with a stop top 54, the stop top 54 is located between the first expansion cone 52 and the second expansion cone 53, and the stop top 54 can be limitedly engaged with the second expansion cone 53.

[0032] By arranging an upper expansion pipe 1 and a lower expansion pipe 2 at the front and rear ends of the leakage position and connecting them in the middle through a connecting sleeve 3, the front and rear ends of the leakage position can be directly blocked, thereby eliminating the need to accurately determine the leakage position, saving construction time, improving construction efficiency, and having strong adaptability; in addition, the expansion assembly 5 uses a first expansion cone 52 and a second expansion cone 53 to expand, subsidize and block the upper expansion pipe 1 and the lower expansion pipe 2 respectively, avoiding the use of one expansion cone during the subsidizing process of a long well section, avoiding excessive travel of the expansion cone, thereby causing excessive wear of the expansion cone, causing failure of the expansion cone, and making it impossible to perform subsidizing.

[0033] like Figure 1As shown, in order to form a stable seal between the upper expansion tube 1 and the lower expansion tube 2 and the original well wall during the expansion process, the outer walls of the upper expansion tube 1 and the lower expansion tube 2 are circumferentially provided with expansion seals 6, and multiple expansion seals 6 are distributed at intervals along the axial direction of the upper expansion tube 1 and the lower expansion tube 2, so that during the expansion process, the upper expansion tube 1 and the lower expansion tube 2 and the original well wall jointly squeeze the expansion seals 6, thereby forming a stable seal. Furthermore, the expansion seals 6 are made of high temperature and high pressure resistant rubber parts, and the rubber parts are stably fixed to the upper expansion tube 1 and the lower expansion tube 2 by vulcanization.

[0034] In this embodiment, the number and length of the connecting sleeves 3 can be calculated according to the length of the specific long well section repair. When the repair distance is too long, the number of connecting sleeves 3 is too large, and multiple long well section casing damage repair devices can be set to perform segmented processing. In addition, the first expansion cone 52 and the second expansion cone 53 in this embodiment have an inner cavity, so that pressure fluid can pass through.

[0035] It should be noted that the blocked end of the lower expansion tube 2 is connected and blocked by a blocking piece 4; the connecting sleeve 3 is connected to the end of the lower expansion tube 2 away from the blocking piece 4, and the connection between the blocking piece 4 and the lower expansion tube 2 can be a threaded connection. When the repair is completed, the blocking piece 4 can be cut and removed to allow the upper expansion tube 1, the connecting sleeve 3 and the lower expansion tube 2 to pass through.

[0036] like Figures 1 to 3As shown, the injection of pressure liquid is completed through the center tube 51. In this embodiment, the center tube 51 includes a first tube 511 and a second tube 512. The first end of the first tube 511 is connected to the first expansion cone 52, so that the first tube 511 is connected to the inner cavity of the first expansion cone 52, so that the pressure liquid enters between the first expansion cone 52 and the sealing member 4, so that the first expansion cone 52 is moved in the lower expansion tube 2 by continuously injecting the pressure liquid; illustratively, the first tube 511 and the first expansion cone 52 are sealed and screwed, but not limited to, so that the first expansion cone 52 and the center tube 51 are conveniently installed in the lower expansion tube 2 through a detachable connection. The second end of the first tube 511 is provided with a top portion 54 protruding from the first tube 511, and the top portion 54 is provided with an inner cavity, the inner cavity of the top portion 54 is connected to the first tube 511, one end of the second tube 512 is detachably plugged into the inner cavity of the top portion 54, and the other end of the second tube 512 passes through the inner cavity of the second expansion cone 53, and is passed out from the upper expansion tube 1 for connecting to an external pressure liquid injection device. In this embodiment, the top portion 54 is located between the first expansion cone 52 and the second expansion cone 53, so that the upward movement of the first expansion cone 52 can push the top portion 54 upward to approach the second expansion cone 53. When the first expansion cone 52 completes the expansion of the lower expansion tube 2, the top portion 54 is then limitedly abutted with the second expansion cone 53, and the top portion 54 continues to move upward, pushing the second expansion cone 53 to move in the upper expansion tube 1. It should be noted here that, since the number of connecting sleeves 3 is generally multiple, the distance from the abutment top 54 to the second expansion cone 53 will be greater than the distance that the first expansion cone 52 travels in the lower expansion pipe 2, so that the first expansion cone 52 and the second expansion cone 53 can be prevented from expanding the lower expansion pipe 2 and the upper expansion pipe 1 at the same time, thereby reducing the required action pressure. Exemplarily, the second pipe 512 is connected to the abutment top 54 by, but not limited to, a sealed screw connection, so that the length of the second pipe 512 can be replaced according to different length requirements to facilitate the adaptation of long well sections of different lengths.

[0037] like Figure 3As shown, in this embodiment, in order to ensure the stable connection between the second expansion cone 53 and the abutting top 54, the inner cavity wall of the second expansion cone 53 is provided with a first abutting surface, and the outer wall of the abutting top 54 is provided with a second abutting surface. When the abutting top 54 enters the inner cavity of the second expansion cone 53, the first abutting surface and the second abutting surface abut and cooperate to limit, thereby pushing the second expansion cone 53 to move. Specifically, the second abutting surface is a sloped surface facing the second expansion cone 53 to provide abutting force to the second expansion cone 53. Furthermore, in order to form a sealed state when the second expansion cone 53 and the abutting limit cooperate to avoid pressure leakage, the outer side of the abutting top 54 is provided with a plurality of first grooves distributed along the axial direction of the central tube 51, and a first sealing member 55 is arranged in each first groove, so that the first sealing member 55 is squeezed mutually by the abutting top 54 and the first expansion cone 52 to form a stable seal. Exemplarily, the first sealing member 55 adopts a sealing ring resistant to high temperature and high pressure.

[0038] In this embodiment, the second expansion cone 53 is firmly abutted against the upper expansion tube 1, and a plurality of third grooves (not shown in the figure) distributed along the axial direction of the center tube 51 are arranged on the surface of the second expansion cone 53 in a circumferential direction, and a third sealing member is arranged in each third groove, so that the third sealing member is tightly clamped by the second expansion cone 53 and the upper expansion tube 1, so that the second expansion cone 53 is stationary relative to the upper expansion tube 1 without external force; in addition, the third sealing member can prevent pressure from leaking between the upper expansion tube 1 and the second expansion cone 53. Similarly, a second groove (not shown in the figure) is arranged on the outer surface of the first expansion cone 52 in a circumferential direction, and a second sealing member is arranged in the second groove, so that the sealing between the first expansion cone 52 and the lower expansion tube 2 can be ensured.

[0039] like Figure 1As shown, in this embodiment, the diameters of the upper expansion tube 1, the connecting sleeve 3 and the lower expansion tube 2 become smaller in sequence; the connecting sleeve 3 extends into the upper expansion tube 1 to be connected thereto, and the lower expansion tube 2 extends into the connecting sleeve 3 to be connected thereto, and a coaxial connection is adopted, and from the upper expansion tube 1 to the lower expansion tube 2, the connecting sleeve 3 located at the rear extends into the previous connecting sleeve 3 to be connected thereto; thereby, a stepped connection is formed from the upper expansion tube 1 to the lower expansion tube 2, and this connection method can eliminate the connector between the tubes, thereby also enabling the first expansion cone 52 to move smoothly during the process of moving from the lower expansion tube 2 to the upper expansion tube 1, avoiding obstruction and interference at the connection between the tubes; it should be noted here that this connection method can also enable the connecting sleeve 3 to form a limiting step (i.e., the end of the connecting sleeve 3) in the upper expansion tube 1, which can assist in limiting the movement of the second expansion cone 53 in the direction of the lower expansion tube 2, thereby improving the stability of the first expansion cone 52. Specifically, the connecting sleeve 3 adopts a collarless sleeve, and the connecting sleeve 3 is threadedly connected to the upper expansion pipe 1; adjacent connecting sleeves 3 are threadedly connected; and the connecting sleeve 3 is threadedly connected to the lower expansion pipe 2, so that the connection is more convenient and quick.

[0040] The present application also provides a long well section casing damage well compensation method, the method adopts the long well section casing damage well compensation device mentioned above, and comprises the following steps:

[0041] First, the length and approximate position of the casing damage section to be repaired are determined according to the detection results, and the number and length of the connecting casings 3 required are determined; the connecting casings 3 are connected in sequence; and the upper expansion pipe 1 installed with the second expansion cone 53 and the lower expansion pipe 2 installed with the first expansion cone 52 and the plugging member 4 are connected to the connecting casing 3; during this process, the central pipe 51 is installed simultaneously to form a complete long-section casing damage well repair device;

[0042] Lower the long well section casing damage well compensation device to the actual compensation position to ensure that the long well section casing damage well compensation device blocks the long well section accurately;

[0043] The center pipe 51 is connected to the drilling tool, and a pressure liquid is injected into the center pipe 51 for pressure using a surface pressure pump or a cement truck. The pressure liquid can be, but is not limited to, clean water. When the drilling pressure reaches a certain level, the pressure liquid drives the first expansion cone 52 to move upward, and at the same time, the center pipe 51 is lifted. The first expansion cone 52 will expand the lower expansion pipe 2 radially, and the lower expansion pipe 2 will stick to the inner wall of the original well section, squeezing the expansion seal 6 to form a seal; when the first expansion cone 52 completes the expansion work and enters the connecting casing 3, the drilling pressure will drop. At this time, the pressure liquid injection can be stopped, and the center pipe 51 can be slowly lifted;

[0044] When the abutment top 54 is engaged with the second expansion cone 53, the drilling pressure will increase, and the pressure fluid will continue to be injected. If the drilling pressure gradually increases, it proves that the abutment top 54 and the second expansion cone 53 are successfully abutted. If the drilling pressure does not increase, the central pipe 51 will continue to be lifted to make the abutment top 54 abut against the second expansion cone 53, and then the pressure fluid will continue to be injected to make the second expansion cone 53 move upward, radially expand the upper expansion pipe 1, and stick the upper expansion pipe 1 to the inner wall of the original well section, squeezing the expansion seal 6 to form a seal until the second expansion cone 53 passes completely, and then the central pipe 51 and the associated first expansion cone 52 and second expansion cone 53 are taken out.

[0045] 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 long well casing damage repair device, comprising an upper expansion pipe (1) and a lower expansion pipe (2), wherein one end of the lower expansion pipe (2) is open, and is characterized in that: Also includes: A connecting sleeve (3), wherein a plurality of the connecting sleeves (3) are connected in sequence, wherein the connecting sleeve (3) at the head end is connected to one end of the upper expansion pipe (1), and the connecting sleeve (3) at the tail end is connected to the open end of the lower expansion pipe (2); An expansion assembly (5), the expansion assembly (5) comprising a central tube (51), a first expansion cone (52) and a second expansion cone (53), the first expansion cone (52) being located in the lower expansion tube (2), the second expansion cone (53) being arranged in the upper expansion tube (1), the central tube (51) moving through the inner cavity of the second expansion cone (53) and connected to the first expansion cone (52) to form a through passage with the inner cavity of the first expansion cone (52); the central tube (51) being provided with an abutment top portion (54), the abutment top portion (54) being located between the first expansion cone (52) and the second expansion cone (53), the abutment top portion (54) being capable of being positionally engaged with the second expansion cone (53).

2. The long well section casing damage compensation device according to claim 1 is characterized in that: The central tube (51) comprises a first tube (511) and a second tube (512), the first end of the first tube (511) is connected to the first expansion cone (52), the second end of the first tube (511) is provided with the abutment top (54), the abutment top (54) is provided with an inner cavity, the second tube (512) is passed through the inner cavity of the second expansion cone (53), and is detachably plugged into the inner cavity of the abutment top (54).

3. The long well section casing damage compensation device according to claim 2 is characterized in that: The inner cavity wall of the second expansion cone (53) is provided with a first abutting surface, and the outer wall of the abutting top portion (54) is provided with a second abutting top surface that matches the first abutting top surface.

4. The long well casing damage compensation device according to claim 1 is characterized in that: A plurality of first sealing members (55) distributed axially along the central tube (51) are sleeved on the outer side of the abutting portion (54).

5. The long well casing damage compensation device according to claim 1 is characterized in that: A second sealing member is circumferentially arranged on the outer surface of the first expansion cone (52).

6. The long well casing damage compensation device according to claim 1 is characterized in that: A third sealing member is circumferentially arranged on the outer surface of the second expansion cone (53), and the second expansion cone (53) and the upper expansion pipe (1) tightly clamp the third sealing member so that the two are relatively still in the absence of external force.

7. The long well casing damage compensation device according to claim 1 is characterized in that: The diameters of the upper expansion pipe (1), the connecting sleeve (3) and the lower expansion pipe (2) decrease in sequence.

8. The long well casing damage compensation device according to claim 1 is characterized in that: The connecting sleeve (3) is threadedly connected to the upper expansion pipe (1); adjacent connecting sleeves (3) are threadedly connected to each other; and the connecting sleeve (3) is threadedly connected to the lower expansion pipe (2).

9. The long well casing damage compensation device according to any one of claims 1 to 8, characterized in that: The outer walls of the upper expansion tube (1) and the lower expansion tube (2) are both circumferentially provided with expansion seals (6), and a plurality of the expansion seals (6) are distributed at intervals along the axial direction of the upper expansion tube (1) and the lower expansion tube (2).

10. A method for compensating a casing damaged well in a long well section, using a compensating device for a casing damaged well in a long well section as claimed in any one of claims 1 to 9, characterized in that: The steps include: The number and length of the required connecting casing (3) are determined according to the repair length of the long well section, and together with the expansion assembly (5), the upper expansion pipe (1) and the lower expansion pipe (2), the long well section casing damage repair device is formed; Delivering the long well section casing damage compensation device to a designated well depth; A pressure liquid is injected through the central tube (51) to push the first expansion cone (52) upward to pass through the lower expansion tube (2), thereby expanding the lower expansion tube (2); when the top portion (54) is engaged with the second expansion cone (53), the pressure liquid is continuously injected to push the second expansion cone (53) through the upper expansion tube (1), until the second expansion cone (53) completely passes through.

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