A casing lowering guiding and straightening structure for high-angle wellbore construction

Abstract

The invention discloses a casing lowering guiding and straightening structure for high-angle wellbore construction, and relates to the technical field of straightening structures. The casing lowering operation is consistent with the straightening principle used in the drilling operation, but there is a difference in that: in the process of cooperating with the casing lowering, an active deformation process occurs under the influence of the wellbore environment, which is specifically manifested in the bending process of the inner sleeve, the cooperative spring frame and the force spring frame. The cooperative spring frame is used as a key structure, and the purpose of automatic straightening is achieved through the cooperative spring frame. It should be noted that: in the bending process of the overall structure, the deformation process of the cooperative spring frame and the force spring frame is further limited by a connecting cable assembly. The essence of this is that the cooperative spring frame is subject to two actions of direction limitation and force limitation from the force spring frame and the active limitation process of the connecting cable assembly, and the force spring frame is also subject to the limitation process of the connecting cable assembly. The overall deformation process is coordinated with the casing lowering process in an interactive manner to achieve straightening guidance.

Description

Technical Field

[0001] The present invention relates to the technical field of centralizing structures, and particularly relates to a casing lowering guiding and centralizing structure for large-angle wellbore construction. Background Art

[0002] The casing lowering operation in the drilling construction process is described. Its essence is to reinforce the wellbore (cementing function). Specifically, it mainly uses special instruments. For example, referring to the relevant content in the publication number CN118601490A, the process of lowering the casing is basically similar to the essence of the drilling operation, avoiding direct damage to the wellbore and ensuring the operation requirements (lowering position, drilling angle).

[0003] During the process of lowering the casing, a centralizing structure needs to be added to position the casing. However, for large-angle wells, due to the complex wellbore environment, and the conventional centralizing structure mainly utilizes its own elastic supporting force, it cannot fully adapt to the wellbore environment in large-angle wells, directly affecting the connection position of each section of the casing. For example, problems such as misalignment during casing docking and obvious collisions with the wellbore wall when lowering the casing occur. And it should also be noted that: the centralizing structure should not only ensure the casing is centered but also avoid the centralizing structure increasing the resistance during casing lowering. For this, the present application proposes a solution. Summary of the Invention

[0004] The purpose of the present invention is to provide a casing lowering guiding and centralizing structure for large-angle wellbore construction. Regarding the cementing operation in large-angle wells, because the wellbore environment in large-angle wells is complex, it is difficult to maintain or change the lower position during the process of lowering the casing, directly affecting the casing docking quality and even causing related problems of damaging the wellbore environment.

[0005] The purpose of the present invention can be achieved by the following technical solutions: A casing lowering guiding and centralizing structure for large-angle wellbore construction, the centralizing structure is arranged at the lower side position of the casing, and the centralizing structure includes an inner sleeve, a spring frame assembly, and a connecting cable assembly. The spring frame assembly consists of a stress spring frame and a cooperating spring frame. The connecting cable assembly is arranged at the position between the corresponding spring frame assembly and the inner sleeve, and the connecting cable assembly includes a directional cable loop, a directional sleeve, a ball, and a double-sided spring rod;

[0006] The cooperating spring frame is installed at the outer position of the stress spring frame. The stress spring frame is provided with a deformation limiting part corresponding to the connecting cable assembly in the vertical direction at the outer position corresponding to the cooperating spring frame. A recessed ball groove corresponding to the deformation limiting part is provided on the outer wall of the inner sleeve. One end of the directional sleeve is installed on the cooperating spring frame, and the directional sleeve is slidably connected to the stress spring frame.

[0007] It is further configured that: the middle end portion of the inner sleeve is in a curved arch shape along the position pointing to the center point of the inner sleeve, and the spring frame assembly is arranged in a ring array along the center point of the inner sleeve.

[0008] It is further configured that: the cross-sections of the force spring frame and the cooperative spring frame are in a curved arch shape along a position away from the center point of the inner sleeve, and the curvature of the cooperative spring frame is greater than the curvature of the force spring frame.

[0009] It is further configured as follows: the horizontal planes of the center points of the force spring frame, the cooperative spring frame and the inner sleeve along the vertical direction are in the same plane, the upper end position of the force spring frame and the inner sleeve are fixedly connected, and the lower end position of the force spring frame and the inner sleeve are slidably connected along the vertical direction.

[0010] It is further configured as follows: a locking ring corresponding to the lower end portion of the force spring frame is arranged at the lower end position of the inner sleeve.

[0011] It is further configured as follows: the deformation limiting portions are linearly and equidistantly distributed along the vertical direction, and the position of one of the deformation limiting portions is located on the center point plane of the inner sleeve along the vertical direction, and the directional grommet is arranged in the yielding ball groove.

[0012] It is further configured as follows: a connecting rod is slidably installed on the directional sleeve along the direction pointing to the inner sleeve, and a force spring is installed between the inside of the directional sleeve and one end of the connecting rod, and the other end of the connecting rod matches the bidirectional spring rod.

[0013] It is further configured as follows: the balls are mounted on both ends of the bidirectional spring rod, and the balls are slidably connected to the directional eyelet, and the setting position of the bidirectional spring rod matches the setting position of the force spring frame.

[0014] It is further configured as follows: the other end of the connecting rod is arranged at the middle position of the bidirectional spring rod, and a ball sleeve is installed at the other end of the connecting rod, a rotor ball corresponding to the ball sleeve is installed at the middle position of the bidirectional spring rod, and the ball is movably connected in the give-way ball groove.

[0015] The present invention has the following beneficial effects:

[0016] The overall structure is a straightening structure set up for the casing lowering operation, specifically guiding the casing lowering process. For this purpose, the overall structure is firstly limited in its setting position relative to the casing, specifically reflected in the lower position of one of the casings. Its essence is that the upper position of the inner sleeve is in a fixed connection state with the lower position of one of the casings. In the process of lowering the casing, the cooperative spring frame and the force spring frame are affected by the wellbore environment and deform and bend, ensuring that the casing is placed in the designated position in a relatively centered state. The cooperative spring frame is a key elastic support structure, and it also needs to be simultaneously subjected to the elastic restriction effect of the force spring frame.

[0017] Based on the above content, the overall structure first limits the structural appearance of the cooperative spring frame, the force spring frame and the inner sleeve, so as to limit the bending deformation direction of the three. A connecting rope assembly is further arranged according to the setting position of the three. In essence, it does not serve as a connecting structure of the three, but as a "transfer structure" of stress when the three are deformed. Specifically, under the influence of the environment of the highly inclined shaft, the three first undergo a relatively independent bending deformation process, but further interfere with the deformation process of the three through the stress transfer process, so as to ensure that the cooperative spring frame can better contact the well wall, but will not cause excessive pressure on the well wall and affect the structural stability of the inner wall of the well. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 This is a structural schematic diagram of a casing lowering guiding and straightening structure for high-angle wellbore construction proposed by the present invention;

[0020] Figure 2 This is a schematic diagram of the structure of an inner sleeve in a casing lowering guide and straightening structure for high-angle wellbore construction proposed by the present invention;

[0021] Figure 3 A schematic diagram of the structure of a spring frame assembly in a casing lowering guide and straightening structure for high-angle wellbore construction proposed by the present invention;

[0022] Figure 4 A front view of a spring frame assembly corresponding to an inner sleeve in a casing lowering guide and straightening structure for high-angle wellbore construction proposed by the present invention;

[0023] Figure 5 This is a structural schematic diagram of a connecting cable assembly in a casing lowering guide and straightening structure for high-angle wellbore construction proposed by the present invention;

[0024] Figure 6 The invention provides a casing lowering guide and straightening structure for high-angle wellbore construction. Figure 5 A top view of

[0025] Figure 7 The invention provides a casing lowering guide and straightening structure for high-angle wellbore construction. Figure 5 Cross-section of the directional casing.

[0026] In the figure: 1, inner sleeve; 101, give way ball groove; 2, force spring frame; 201, deformation limiting part; 3, cooperative spring frame; 4, locking ring; 6, directional cable ring; 5, directional sleeve; 7, ball; 8, bidirectional spring rod; 9, force spring; 10, connecting rod. DETAILED DESCRIPTION

[0027] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] Embodiment 1: The cementing operation in a highly deviated well is described. Since the wellbore environment of a highly deviated well is complex, it is difficult to maintain or change the lower position during the casing lowering process, which directly affects the casing docking quality and even causes problems related to the damage to the wellbore environment. The following technical solutions are proposed:

[0029] Reference Figures 1 - 7 In this embodiment, a casing lowering guiding and straightening structure for high-angle wellbore construction is provided. The straightening structure is arranged at the lower side of the casing, and the straightening structure comprises an inner sleeve 1, a spring frame assembly and a connecting cable assembly. The spring frame assembly comprises a force spring frame 2 and a cooperative spring frame 3. The connecting cable assembly is arranged at a position between the corresponding spring frame assembly and the inner sleeve 1, and the connecting cable assembly comprises a directional cable ring 6, a directional casing 5, a ball 7 and a bidirectional spring rod 8;

[0030] The cooperative spring frame 3 is installed at the external position of the force spring frame 2. The force spring frame 2 is provided with a deformation limiting portion 201 corresponding to the connecting cable assembly at the external position corresponding to the cooperative spring frame 3 in the vertical direction. The outer wall of the inner sleeve 1 is provided with a yielding ball groove 101 corresponding to the deformation limiting portion 201. One end of the directional sleeve 5 is installed on the cooperative spring frame 3, and the directional sleeve 5 and the force spring frame 2 are slidably connected. The middle end of the inner sleeve 1 is in a curved arch shape along the position pointing to the center point of the inner sleeve 1. The spring frame assembly is arranged in a ring array along the center point of the inner sleeve 1. The cross-sections of the force spring frame 2 and the cooperative spring frame 3 are in a curved arch shape along the position away from the center point of the inner sleeve 1, and the bending curvature of the cooperative spring frame 3 is greater than the bending curvature of the force spring frame 2.

[0031] Basic principle: The overall structure has the same purpose as the conventional centralizing structure, which is to ensure the centrality. However, in the present invention, it mainly aims at the cementing process in large-angle deviated well operations. Its essence is to lower several casing pipes according to the technological requirements. For this purpose, a relevant centralizing structure is proposed for the process of lowering the casing pipes. First, the installation position of the centralizing structure proposed in the present invention is restricted. Specifically, it is installed on the lower side of one of the casing pipes. It still supports the wellbore through an elastic support member, but it is different from the conventional centralizing structure as follows:

[0032] S1: The overall structure continuously moves down to the designated position with the casing pipe. In the initial state, since the lower side of the force-bearing spring frame 2 is slidably connected to the inner sleeve 1, it can be understood that the bending arc of the force-bearing spring frame 2 is the largest in the initial state. It will deform until it contacts the inner wall of the wellbore, and the bending arc is reduced. Specifically, the lower side of the force-bearing spring frame 2 slides relative to the inner sleeve 1. The purpose is to prevent the force-bearing spring frame 2 from directly exerting a large pressure on the wellbore and damaging the stability of the inner wall of the wellbore;

[0033] S2: Based on S1, in essence, the coordinated spring frame 3 directly contacts the inner wall of the wellbore and undergoes active deformation and bending. However, the coordinated spring frame 3 will be interfered by the force-bearing spring frame 2. It can be understood that when the coordinated spring frame 3 undergoes a large bending deformation, it will exert a greater pressure on the wellbore. For this reason, the force-bearing spring frame 2 needs to bear the excessive pressure generated by the coordinated spring frame 3;

[0034] It should also be noted that: due to the influence of the large-angle deviated wellbore environment, the inner sleeve 1 will also undergo an applicable bending process. However, the bending process of the inner sleeve 1 will also indirectly affect the bending deformation process of the force-bearing spring frame 2. Thus, the three bending processes of the overall structure will interfere with each other, enabling the overall structure to better adapt to the large-angle deviated wellbore environment.

[0035] Embodiment 2: This embodiment makes a supplementary description of the bending processes of the force-bearing spring frame 2 and the coordinated spring frame 3:

[0036] The horizontal planes of the central points of the force-bearing spring frame 2, the coordinated spring frame 3, and the inner sleeve 1 in the vertical direction are in the same plane. The upper end of the force-bearing spring frame 2 is fixedly connected to the inner sleeve 1, and the lower end of the force-bearing spring frame 2 is slidably connected to the inner sleeve 1 in the vertical direction. A locking ring 4 corresponding to the lower part of the force-bearing spring frame 2 is provided at the lower end of the inner sleeve 1. The deformation limiting parts 201 are linearly and equally spaced in the vertical direction, and the position of one of the deformation limiting parts 201 is on the central point plane of the inner sleeve 1 in the vertical direction. The directional cable ring 6 is arranged in the relief ball groove 101.

[0037] Scheme description: Combining Figure 2 and Figure 4It is described that the inner sleeve 1 first has a certain curvature, and several through grooves are provided in the middle position to ensure that the inner sleeve 1 has the ability to withstand bending effects. The following supplements are made to the bending deformation processes of the force-bearing spring frame 2 and the co-acting spring frame 3:

[0038] S4: When the co-acting spring frame 3 contacts the inner wall of the shaft, the co-acting spring frame 3 undergoes compressive deformation, which is manifested as a decrease in curvature. During this process, since the co-acting spring frame 3 is installed on the force-bearing spring frame 2, the force-bearing spring frame 2 will also undergo a passive bending process due to the interference of the co-acting spring frame 3. It should also be noted that: although the inner sleeve 1 has the ability to bend and deform, because there is a sliding ability between the lower end of the force-bearing spring frame 2 and the inner sleeve 1, the bending process of the inner sleeve 1 will not directly interfere with the force-bearing spring frame 2. For this reason, the force-bearing spring frame 2, the co-acting spring frame 3, and the inner sleeve 1 are required to be made of soft materials with elastic ability;

[0039] S5: For this reason, a plurality of relief ball grooves 101 are provided on the outer wall of the inner sleeve 1. This purpose is also to ensure that the inner sleeve 1 can undergo free bending deformation. However, the key lies in the deformation limiting part 201 provided on the force-bearing spring frame 2. Under normal conditions, when the force-bearing spring frame 2 and the co-acting spring frame 3 are both bent outward in an arched shape, when the curvature of the co-acting spring frame 3 decreases, the co-acting spring frame 3 will also perform a curvature reduction action. However, through the three deformation limiting parts 201, the bending direction in the force-bearing spring frame 2 is further changed. It can be directly understood that: when the force-bearing spring frame 2 is affected by the co-acting spring frame 3, it will not undergo a bending process in a single direction, but rather optimizes the bending process in multiple directions in cooperation with the bending process of the inner sleeve 1, specifically in further cooperation with the large inclined shaft well environment.

[0040] Example 3: Further propose that the associated connecting cable assembly supplements the deformation processes in Example 1 and Example 2:

[0041] The directional sleeve 5 is slidably installed with a connecting rod 10 in the direction pointing to the inner sleeve 1, and a force-bearing spring 9 is installed between the inside of the directional sleeve 5 and one end of the connecting rod 10. The other end of the connecting rod 10 is matched with the double-sided spring rod 8. The balls 7 are installed at both ends of the double-sided spring rod 8, and the balls 7 are slidably connected to the directional cable loop 6. The setting position of the double-sided spring rod 8 is matched with the setting position of the force-bearing spring frame 2. The other end of the connecting rod 10 is arranged at the middle section of the double-sided spring rod 8, and a ball sleeve is installed at the other end of the connecting rod 10. A rotor ball corresponding to the ball sleeve is installed at the middle section of the double-sided spring rod 8. The balls 7 are movably connected in the relief ball grooves 101.

[0042] Scheme description: In combination with Figures 5 - 7It is to be noted again that: each yielding ball groove 101 is used to place a ball 7, ensuring that the ball 7 can slide freely in the yielding ball groove 101, and each ball 7 is connected in series through a directional grommet 6, and ensuring that the ball 7 can also slide in the directional grommet 6, and combined with the content of S5 in the second embodiment, because the inner sleeve 1 needs to bend and deform in a small amplitude, it is necessary to further limit the outer diameter of the ball 7, specifically, the outer diameter of the ball 7 is smaller than the inner diameter of the yielding ball groove 101, but the ball 7 will not be separated from the yielding ball groove 101, the purpose of which is to prevent the ball 7 from completely interfering with the deformation process of the inner sleeve 1;

[0043] However, the key point to be explained is that the directional sleeve 5 connected to each of the cooperative spring frames 3 is a key structure for transmitting the stress on the cooperative spring frame 3. The essence is that the cooperative spring frame 3 is compressed and deformed, causing the directional sleeve 5 to move linearly in the direction of the center point of the inner sleeve 1, and combined with Figure 7 The linear movement of the directional sleeve 5 will not directly affect the force spring frame 2. Therefore, it is necessary to ensure that a through hole larger than the outer diameter of the directional sleeve 5 is provided on the force spring frame 2.

[0044] In this process, the force spring 9 inside is compressed and generates pressure on the connecting rod 10 in the direction of the center point of the inner sleeve 1, specifically on the two-way spring rod 8. Because the ball sleeve connected to the connecting rod 10 and the rotor ball on the two-way spring rod 8 are not completely fixed, they have a certain degree of mobility. However, the key is that the two-way spring rod 8 is subjected to the pressure from the connecting rod 10 and undergoes an outward expansion type bending process, so that Figure 6 For a single bidirectional spring rod 8, the two balls 7 thereon move away from each other in the yielding ball groove 101, and this process of the two balls 7 moving away from each other will also interfere with the deformation process of the inner sleeve 1. The key technical point of the overall structure is: the purpose of straightening the casing is achieved by contacting the large inclined shaft with the cooperative spring frame 3, but no large pressure is generated on the inner wall of the shaft.

[0045] In summary, the casing lowering operation and the straightening principle used in the drilling operation are consistent, but there is a difference in that: in the process of cooperating with the casing lowering, an active deformation process occurs under the influence of the wellbore environment, which is specifically manifested in the bending process of the inner sleeve 1, the cooperative spring frame 3 and the force spring frame 2. The cooperative spring frame 3 is taken as the key structure, and the purpose of automatic straightening is achieved through the cooperative spring frame 3. It should be noted that: in the bending process of the overall structure, the deformation process of the cooperative spring frame 3 and the force spring frame 2 is further restricted by the connecting cable assembly. Its essence is that the cooperative spring frame 3 is subject to the two actions of direction restriction and force restriction from the force spring frame 2 and the active restriction process of the connecting cable assembly, and the force spring frame 2 is also subject to the restriction process of the connecting cable assembly. The overall deformation process is coordinated with the casing lowering process in an interactive manner to achieve straightening guidance.

[0046] The above content is only an example and illustration of the structure of the present invention. Those skilled in the art of this technology can make various modifications, supplements, or use similar methods to substitute for the specific embodiments described, as long as they do not deviate from the structure of the invention or exceed the scope defined by this claim book, they should all fall within the protection scope of the present invention.

[0047] In the description of this specification, the description with reference to terms such as "an embodiment", "example", "specific example", etc. means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0048] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not elaborate on all details and do not limit the invention to only the specific implementation manners. Obviously, many modifications and variations can be made according to the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the present invention, so that those skilled in the art can well understand and utilize the present invention. The present invention is only limited by the claim book and its full scope and equivalents.

Claims

1. A casing lowering guiding and straightening structure for high-angle wellbore construction, characterized in that: The centralizing structure is arranged at the lower side of the casing, and the centralizing structure includes an inner sleeve (1), a spring frame assembly and a connecting cable assembly. The spring frame assembly consists of a stress spring frame (2) and a cooperating spring frame (3). The connecting cable assembly is arranged at the position corresponding to the spring frame assembly and the inner sleeve (1), and the connecting cable assembly includes an orientation cable loop (6), an orientation casing (5), a ball (7) and a bi-directional spring rod (8). The cooperating spring frame (3) is installed at the outer position of the stress spring frame (2). The stress spring frame (2) is provided with a deformation limiting part (201) corresponding to the connecting cable assembly in the vertical direction at the outer position corresponding to the cooperating spring frame (3). A relief ball groove (101) corresponding to the deformation limiting part (201) is provided on the outer wall of the inner sleeve (1). One end of the orientation casing (5) is installed on the cooperating spring frame (3), and the orientation casing (5) is slidably connected to the stress spring frame (2). The cross-sections of the stress spring frame (2) and the cooperating spring frame (3) are in a curved arch shape along the position away from the center point of the inner sleeve (1), and the bending radian of the cooperating spring frame (3) is greater than that of the stress spring frame (2). The deformation limiting parts (201) are linearly and equally spaced in the vertical direction, and the position of one of the deformation limiting parts (201) is located on the central plane of the inner sleeve (1) in the vertical direction. The orientation cable loop (6) is arranged in the relief ball groove (101). The balls (7) are installed at both ends of the bi-directional spring rod (8), and the balls (7) are slidably connected to the orientation cable loop (6). The setting position of the bi-directional spring rod (8) matches the setting position of the stress spring frame (2).

2. The casing lowering guiding and straightening structure for large-inclination wellbore construction according to claim 1, characterized in that, The middle part of the inner sleeve (1) is in a curved arch shape along the direction pointing to the center point of the inner sleeve (1), and the spring frame assembly is arranged in a circular array along the center point of the inner sleeve (1).

3. The casing lowering guiding and centralizing structure for large-angle wellbore construction according to claim 1, characterized in that, The horizontal planes of the central points of the stress spring frame (2), the cooperating spring frame (3) and the inner sleeve (1) in the vertical direction are in the same plane. The upper end of the stress spring frame (2) is fixedly connected to the inner sleeve (1), and the lower end of the stress spring frame (2) is slidably connected to the inner sleeve (1) in the vertical direction.

4. A casing lowering guiding and centralizing structure for large-inclination wellbore construction according to claim 1, characterized in that, A locking ring (4) corresponding to the lower part of the stress spring frame (2) is arranged at the lower end of the inner sleeve (1).

5. The casing lowering guiding and centralizing structure for large-inclination wellbore construction according to claim 1, wherein, A connecting rod (10) is slidably installed in the orientation casing (5) along the direction pointing to the inner sleeve (1), and a stress spring (9) is installed between the inside of the orientation casing (5) and one end of the connecting rod (10). The other end of the connecting rod (10) matches the bi-directional spring rod (8).

6. The casing lowering guiding and centralizing structure for large-inclination wellbore construction according to claim 5, characterized in that, The other end of the connecting rod (10) is arranged at the middle position of the bi-directional spring rod (8), and a ball sleeve is installed at the other end of the connecting rod (10). A rotor ball corresponding to the ball sleeve is installed at the middle position of the bi-directional spring rod (8). The balls (7) are movably connected in the relief ball groove (101).

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