Elastic Centralizer Limiting Device for Couplingless Casing

Abstract

An embodiment of the present application provides a limit device for an elastic centralizer of a non-coupling casing, including: an upper limit part and a lower limit part. The upper limit part includes a first half-ring and a second half-ring. The first end of the first half-ring is rotatably connected to the first end of the second half-ring. The second end of the first half-ring and the second end of the second half-ring are connected by bolts. The first half-ring and the second half-ring are combined to form a hoop structure. The lower limit part includes a third half-ring and a fourth half-ring. The first end of the third half-ring is rotatably connected to the first end of the fourth half-ring. The second end of the third half-ring and the second end of the fourth half-ring are connected by bolts. The third half-ring and the fourth half-ring are combined to form a hoop structure. A casing centralizer is arranged between the upper limit part and the lower limit part. The upper limit part, the lower limit part, and the casing centralizer are all detachably arranged on the outer side of the casing. By surrounding the upper limit part and the lower limit part on the casing and clamping the casing centralizer between the two, this ensures that the position of the casing centralizer is effectively fixed.

Description

Technical Field

[0001] The embodiments of the present application relate to the technical field of cementing, and in particular, to a limit device for an elastic centralizer of a seamless casing Background Art

[0002] As an important cementing device in the oil and gas exploration field, a casing centralizer can ensure that the casing is centered in the wellbore, reduce the possibility of sticking between the casing and the well wall when the casing is lowered, ensure uniform distribution of the cement sheath, and thus improve the cementing quality.

[0003] To ensure the effective functioning of the casing centralizer, fixing the position of the casing centralizer is an important measure to improve the cementing quality. Currently, in the existing technology for fixing the casing centralizer, the casing centralizer is usually installed at a suitable position on the casing according to the design, and is limited by two upper and lower stop rings and a coupling to prevent the centralizer from sliding up and down.

[0004] However, for seamless casings, since there is no coupling, during the process of lowering the pipe string into the well, if the resistance to pipe string lowering is too large, the elastic centralizer of the seamless casing will slide. Summary of the Invention

[0005] The embodiments of the present application provide a limit device for an elastic centralizer of a seamless casing to prevent the elastic centralizer of the seamless casing from sliding.

[0006] The embodiments of the present application provide a limit device for an elastic centralizer of a seamless casing, including: an upper limit portion and a lower limit portion.

[0007] The upper limit portion includes a first half-ring and a second half-ring. The first end of the first half-ring is rotatably connected to the first end of the second half-ring. The second end of the first half-ring and the second end of the second half-ring are connected by bolts. The first half-ring and the second half-ring are combined to form a hoop structure.

[0008] The lower limit portion includes a third half-ring and a fourth half-ring. The first end of the third half-ring is rotatably connected to the first end of the fourth half-ring. The second end of the third half-ring and the second end of the fourth half-ring are connected by bolts. The third half-ring and the fourth half-ring are combined to form a hoop structure.

[0009] A casing centralizer is provided between the upper limit portion and the lower limit portion. The upper limit portion is used to limit the upper edge of the movement of the casing centralizer, and the lower limit portion is used to limit the lower edge of the movement of the casing centralizer.

[0010] The upper limit portion, the lower limit portion, and the casing centralizer are all detachably arranged outside the casing.

[0011] In a possible design, a first protrusion is provided on the inner ring surface of the first half-ring, and a second protrusion is provided on the inner surface of the second half-ring. The first protrusion and the second protrusion face each other and are used to be stuck at the joint of the upper and lower pipe bodies of the casing. A first anti-slip layer is provided on the inner surface of the lower limit portion.

[0012] In a possible design, at least two first bushings are provided at intervals at the first end of the first half-ring, and at least two of the first bushings are arranged along the axial direction parallel to the axis of the first half-ring;

[0013] At least two second bushings are provided at intervals at the first end of the second half-ring, and at least two of the second bushings are arranged along the axial direction parallel to the axis of the second half-ring;

[0014] Wherein, the first bushing and the second bushing are finger-jointed to form a connected first shaft hole, and a first rotating shaft is inserted through the first shaft hole.

[0015] In a possible design, a first ring sleeve is provided on the outer surface of the second end of the first half-ring, and a second ring sleeve is provided on the outer surface of the second end of the second half-ring. The first ring sleeve and the second ring sleeve face each other and are connected by inserting bolts.

[0016] In a possible design, the first protrusion is a strip-shaped protrusion arranged along the arc of the inner surface of the first half-ring, and the second protrusion is a strip-shaped protrusion arranged along the arc of the inner surface of the second half-ring.

[0017] In a possible design, the first protrusion is formed by the first half-ring protruding from the outer surface to the inner surface, and the second protrusion is formed by the second half-ring protruding from the outer surface to the inner surface.

[0018] In a possible design, a second anti-slip layer is provided on both the inner surface of the first half-ring and the inner surface of the second half-ring, and the thickness of the second anti-slip layer is less than or equal to the height of the first protrusion protruding from the inner surface of the first half-ring;

[0019] Wherein, the height of the first protrusion protruding from the inner surface of the first half-ring is equal to the height of the second protrusion protruding from the inner surface of the second half-ring.

[0020] In a possible design, at least two third bushings are provided at intervals at the first end of the third half-ring, and at least two of the third bushings are arranged along the axial direction of the third half-ring;

[0021] At least two fourth bushings are provided at intervals at the first end of the fourth half-ring, and at least two of the fourth bushings are arranged along the axial direction of the fourth half-ring;

[0022] Wherein, the third bushing and the fourth bushing are finger-jointed to form a communicating second shaft hole, and a second rotating shaft is inserted through the second shaft hole.

[0023] In a possible design, a third collar is provided on the outer surface of the second end of the third half-ring, and a fourth collar is provided on the outer surface of the second end of the fourth half-ring. The third collar and the fourth collar face each other and are connected by inserting bolts.

[0024] In a possible design, the first anti-slip layer is a rubber layer, and anti-slip lines are provided on the surface of the first anti-slip layer.

[0025] The embodiment of the present application provides a limit device for an elastic centralizer of a non-coupling casing, including: an upper limit part and a lower limit part. The upper limit part includes a first half-ring and a second half-ring. The first end of the first half-ring is rotatably connected to the first end of the second half-ring. The second end of the first half-ring and the second end of the second half-ring are connected by bolts. The first half-ring and the second half-ring are joined to form a hoop structure. The lower limit part includes a third half-ring and a fourth half-ring. The first end of the third half-ring is rotatably connected to the first end of the fourth half-ring. The second end of the third half-ring and the second end of the fourth half-ring are connected by bolts. The third half-ring and the fourth half-ring are joined to form a hoop structure. A casing centralizer is provided between the upper limit part and the lower limit part. The upper limit part is used to limit the upper edge of the movement of the casing centralizer, and the lower limit part is used to limit the lower edge of the movement of the casing centralizer. The upper limit part, the lower limit part, and the casing centralizer are all detachably arranged on the outer side of the casing. Wherein, both the upper limit part and the lower limit part can be looped on the casing and can clamp the casing centralizer between them. Since both the upper limit part and the lower limit part can be clamped on the casing, the upper limit part can prevent the elastic centralizer of the non-coupling casing from sliding upward, and the lower limit part can prevent the elastic centralizer of the non-coupling casing from sliding downward, which ensures that the position of the elastic centralizer of the non-coupling casing is effectively fixed. Description of the Drawings

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0027] Figure 1 Installation schematic diagram of the limit device for the elastic centralizer of the non-coupling casing provided by the embodiment of the present application Figure 1 ;

[0028] Figure 2 Schematic diagram of the upper limit part in the limit device for the elastic centralizer of the non-coupling casing provided by the embodiment of the present application;

[0029] Figure 3 Schematic diagram of the lower limit part of the limit device for the collarless casing elastic centralizer provided by the embodiment of the present application;

[0030] Figure 4 Installation schematic of the limit device for the collarless casing elastic centralizer provided by the embodiment of the present application Figure 2 . Specific embodiments

[0031] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are some, but not all, of the embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts shall fall within the protection scope of the present application.

[0032] To facilitate the understanding of the technical solutions of the present application, the relevant concepts involved in the present application will be explained first:

[0033] During the cementing operation in the drilling process, the casing is lowered and cement is injected between the casing and the formation. As an important cementing device in the oil and gas exploration field, the casing centralizer can ensure that the casing is centered in the wellbore, reduce the possibility of sticking between the casing and the well wall during the lowering of the casing, ensure the uniform distribution of the cement sheath, and thus improve the cementing quality. To ensure the effective function of the casing centralizer, fixing the position of the casing centralizer is an important measure to improve the cementing quality.

[0034] Currently, in the existing technology for fixing the casing centralizer, the casing centralizer is usually installed at a suitable position on the casing according to the design, and limited by two upper and lower stop rings and collars to prevent the centralizer from sliding up and down.

[0035] To shorten the drilling cycle and improve the cementing quality, a collarless casing is proposed. However, for a collarless casing, since there is no collar, during the process of lowering the pipe string into the well, if the resistance to pipe string lowering is too large, the elastic centralizer of the collarless casing will slide, which will lead to the problem that the entire casing string cannot be centered.

[0036] Based on the above existing problems, the present application proposes the following technical concept: by providing a limit device for an elastic centralizer of a seamless-coupling casing, the limit device for an elastic centralizer of a seamless-coupling casing includes an upper limit portion and a lower limit portion. By surrounding the upper limit portion and the lower limit portion around the seamless-coupling casing and installing the elastic centralizer of the seamless-coupling casing between the upper limit portion and the lower limit portion. Since both the upper limit portion and the lower limit portion can be clamped on the casing, the upper limit portion can prevent the elastic centralizer of the seamless-coupling casing from sliding upward, and the lower limit portion can prevent the elastic centralizer of the seamless-coupling casing from sliding downward. Therefore, the limit device for an elastic centralizer of a seamless-coupling casing proposed by the present application can ensure that the position of the elastic centralizer of the seamless-coupling casing remains fixed, thus solving the problem that the entire casing cannot be centered due to the sliding of the casing centralizer, and further ensuring the cementing quality.

[0037] To facilitate the understanding of the limit device for an elastic centralizer of a seamless-coupling casing provided by the present application, first, in combination with Figure 1 the installation position of the limit device for an elastic centralizer of a seamless-coupling casing provided in the embodiment of the present application is introduced. Figure 1 The installation schematic diagram of the limit device for an elastic centralizer of a seamless-coupling casing provided in the embodiment of the present application is Figure 1 . As Figure 1 shown, the installation schematic diagram of the limit device for an elastic centralizer of a seamless-coupling casing provided in the embodiment of the present application includes a casing 7, a casing centralizer 300, an upper limit portion 100, and a lower limit portion 200. Among them, the limit device for an elastic centralizer of a seamless-coupling casing provided in the embodiment of the present application is composed of two parts, namely: an upper limit portion 100 and a lower limit portion 200.

[0038] The installation positions of the limit device for an elastic centralizer of a seamless-coupling casing, the casing centralizer, and the casing are as follows:

[0039] A casing centralizer 300 is arranged between the upper limit portion 100 and the lower limit portion 200. The upper limit portion 100 is used to limit the upper edge of the movement of the casing centralizer 300, and the lower limit portion 200 is used to limit the lower edge of the movement of the casing centralizer 300.

[0040] The upper limit portion 100, the lower limit portion 200, and the casing centralizer 300 are all detachably arranged on the outer side of the casing 7.

[0041] Based on the above introduction to the installation positions of the limit device for an elastic centralizer of a seamless-coupling casing, the casing centralizer, and the casing provided in the embodiment of the present application, in order to facilitate the understanding of the technical solution of the present application, next, in combination with Figure 2 , Figure 3 the limit device for a seamless-coupling casing centralizer provided by the present application is introduced. Figure 2 The schematic diagram of the upper limit portion in the limit device for an elastic centralizer of a seamless-coupling casing provided in the embodiment of the present application isFigure 3 Schematic diagram of the lower limit part in the limit device of the collarless casing elastic centralizer provided by the embodiment of the present application:

[0042] The limit device of the collarless casing elastic centralizer proposed in this embodiment includes an upper limit part and a lower limit part. It should be emphasized that since the overall structures of the upper limit part and the lower limit part proposed in the embodiment of the present application are relatively similar, for clear description and easy understanding, in the following introduction of the upper limit part and the lower limit part, the corresponding introduction method is adopted, that is, the structure of the upper limit part is described first, and then the structure of the lower limit part is correspondingly described.

[0043] First, in combination with Figure 2 and Figure 3 The reference numerals and corresponding meanings of the respective components included in the upper limit part and the lower limit part are described respectively. As Figure 2 shown, the upper limit part 100 of the limit device of the collarless casing elastic centralizer provided by the embodiment of the present application specifically includes: a first half ring 1 and a second half ring 2. Among them, a first protrusion 11 is provided on the inner surface of the first half ring 1, and a second protrusion 21 is provided on the inner surface of the second half ring. As Figure 3 shown, the lower limit part 200 of the limit device of the collarless casing elastic centralizer provided by the embodiment of the present application specifically includes: a third half ring 3 and a fourth half ring 4.

[0044] In a possible implementation manner, the upper limit part 100 includes a first half ring 1 and a second half ring 2. The first end of the first half ring 1 is rotatably connected to the first end of the second half ring 2. The second end of the first half ring 1 and the second end of the second half ring 2 are connected by bolts. The first half ring 1 and the second half ring 2 are combined to form a hoop structure. A first protrusion 11 is provided on the inner surface of the first half ring 1, and a second protrusion 21 is provided on the inner surface of the second half ring. Among them, the first protrusion 11 and the second protrusion 21 are arranged oppositely and are used to clamp at the joint of the upper and lower pipe bodies of the casing.

[0045] In a possible implementation manner, the lower limit part 200 includes a third half ring 3 and a fourth half ring 4. The first end of the third half ring 3 is rotatably connected to the first end of the fourth half ring 4. The second end of the third half ring 3 and the second end of the fourth half ring 4 are connected by bolts. The third half ring 3 and the fourth half ring 4 are combined to form a hoop structure.

[0046] Specifically, the overall structures of the upper limit part 100 and the lower limit part 200 can be similar, and both need to be made of a metal material that is corrosion-resistant and has a certain strength.

[0047] In a possible implementation, the structures of the first half-ring 1 and the second half-ring 2 of the upper limit portion 100 may be the same. For example, they can both be formed by bending a sheet material. And to ensure the strength of the first half-ring 1 and the second half-ring 2, reinforcing ribs can be provided on the ring bodies of the first half-ring 1 and the second half-ring 2. For example, the reinforcing ribs can be directly pressed out during the bending process. At the same time, a convex structure can be provided on the inner surface of the upper limit portion 100, for example.

[0048] In a possible implementation, the structures of the third half-ring 3 and the fourth half-ring 4 of the lower limit portion 200 may be the same. For example, they can both be formed by bending a sheet material. And to ensure the strength of the third half-ring 3 and the fourth half-ring 4, reinforcing ribs can be provided on the ring bodies of the third half-ring 3 and the fourth half-ring 4. For example, the reinforcing ribs can be directly pressed out during the bending process. At the same time, a first anti-slip layer is provided on the inner surface of the lower limit portion 200. Specifically, the material of the first anti-slip layer can be rubber, for example, and the specific thickness can be set according to actual needs. To further enhance the anti-slip effect, anti-slip patterns can be provided on the surface of the first anti-slip layer, for example, annular anti-slip patterns or grid anti-slip patterns.

[0049] The embodiment of the present application provides a limit device for an elastic centralizer of a non-coupling casing, including: an upper limit portion and a lower limit portion. The upper limit portion includes a first half-ring and a second half-ring. The first end of the first half-ring is rotatably connected to the first end of the second half-ring, and the second end of the first half-ring and the second end of the second half-ring are connected by bolts. The first half-ring and the second half-ring are combined to form a hoop structure. The lower limit portion includes a third half-ring and a fourth half-ring. The first end of the third half-ring is rotatably connected to the first end of the fourth half-ring, and the second end of the third half-ring and the second end of the fourth half-ring are connected by bolts. The third half-ring and the fourth half-ring are combined to form a hoop structure. A casing centralizer is provided between the upper limit portion and the lower limit portion. The upper limit portion is used to limit the upper edge of the movement of the casing centralizer, and the lower limit portion is used to limit the lower edge of the movement of the casing centralizer. The upper limit portion, the lower limit portion, and the casing centralizer are all detachably arranged on the outside of the casing. Among them, both the upper limit portion and the lower limit portion can be looped around the casing and can clamp the casing centralizer between them. Since both the upper limit portion and the lower limit portion can be clamped on the casing, the upper limit portion can prevent the elastic centralizer of the non-coupling casing from sliding upward, and the lower limit portion can prevent the elastic centralizer of the non-coupling casing from sliding downward, which ensures that the position of the elastic centralizer of the non-coupling casing is effectively fixed.

[0050] On the basis of the above embodiments, the limit device for an elastic centralizer of a non-coupling casing provided by the present application will be further introduced below in combination with a specific embodiment.

[0051] It should be noted that before the formal introduction, first in combination with Figure 2 and Figure 3The reference numerals and corresponding meanings of the respective components included in the upper limit portion and the lower limit portion are further described. For example, Figure 2 As shown, the upper limit portion 100 of the non-coupling casing elastic centralizer limiting device provided in the embodiment of the present application specifically further includes: a first rotating shaft 5, a first bushing 12, a first ring sleeve 13, a second bushing 22, and a second ring sleeve 23. As Figure 3 shown, the lower limit portion 200 of the non-coupling casing elastic centralizer limiting device provided in the embodiment of the present application specifically further includes: a second rotating shaft 6, a third bushing 31, a third ring sleeve 32, a fourth bushing 41, and a fourth ring sleeve 42.

[0052] In a possible implementation manner, at least two first bushings 12 are spaced apart from the first end of the first half-ring 1 of the upper limit portion 100. Among them, at least two first bushings 12 are arranged along the axial direction parallel to the axis of the first half-ring 1. At least two second bushings 22 are spaced apart from the first end of the second half-ring 2 of the upper limit portion 100. Among them, at least two second bushings 22 are arranged along the axial direction parallel to the axis of the second half-ring 2. The first bushing 12 and the second bushing 22 in the upper limit portion 100 are finger-connected to form a communicating first shaft hole, and a first rotating shaft 5 is inserted through the first shaft hole.

[0053] Specifically, a first bushing 12 and a second bushing 22 are respectively arranged at the first end of the first half-ring 1 and the first end of the second half-ring 2, and are rotationally connected by inserting a first rotating shaft 5. This is a better rotational connection method. After the first rotating shaft 5 is inserted into the first shaft hole formed by the first bushing 12 and the second bushing 22, it is necessary to make both ends of the first rotating shaft 5 engage with the first shaft hole to prevent the first rotating shaft 5 from falling off. The engaging method can be, for example, by squeezing the two ends of the first rotating shaft 5 to make them thicker, or by inserting limit pins or limit safety pins at both ends of the first rotating shaft 5.

[0054] In this embodiment, only an exemplary introduction to the specific implementation manner of the engagement between the two ends of the first rotating shaft 5 and the first shaft hole is given, and it is not a limitation on the specific implementation manner of the engagement between the two ends of the first rotating shaft 5 and the first shaft hole. The specific implementation manner of the engagement between the two ends of the first rotating shaft 5 and the first shaft hole can be selected according to actual needs.

[0055] In a possible implementation manner, a first ring sleeve 13 is arranged on the outer surface of the second end of the first half-ring 1, and a second ring sleeve is arranged on the outer surface of the second end of the second half-ring 2. Among them, the first ring sleeve 13 is opposite to the second ring sleeve 23 and is connected by inserting a bolt.

[0056] Specifically, the structures of the first ring sleeve 13 and the second ring sleeve 23 can both be ear-shaped rings. The forming method of the structures of the first ring sleeve 13 and the second ring sleeve 23 can be, for example, integrally formed with the first half-ring 1 and the second half-ring 2, or can be connected by subsequent welding. Among them, when the first ring sleeve 13 and the second ring sleeve 23 are connected by bolts, a gasket can be set to increase the force-bearing area during fastening.

[0057] In a possible implementation manner, the first protrusion 11 is a long strip-shaped protrusion arranged along the arc of the inner surface of the first half-ring 1, and the second protrusion 21 is a long strip-shaped protrusion arranged along the arc of the inner surface of the second half-ring 2.

[0058] Specifically, the long strip-shaped protrusion helps to increase the clamping area at the connection between the upper limiting part 100 and the upper and lower pipe bodies of the casing, and increases the clamping force. At the same time, the first protrusion 11 and the second protrusion 21 are clamped with the groove formed by the chamfer at the connection of the upper and lower casings, so that the fastening between the upper limiting part 100 and the casing by friction is transformed into the shear force between the boss and the groove, with stronger anti-slip performance and no damage to the casing, which can effectively prevent the sliding of the casing centralizer. Further, the first protrusion 11 is formed by the first half-ring 1 protruding from the outer surface to the inner surface, and the second protrusion 21 is formed by the second half-ring 2 protruding from the outer surface to the inner surface.

[0059] Specifically, by deforming to form protrusions on the first half-ring 1 and the second half-ring 2, not only can the clamping between the upper limiting part 100 and the upper and lower pipe bodies of the casing be realized, but also the structural strength of the first half-ring 1 and the second half-ring 2 can be effectively increased.

[0060] In a possible implementation manner, a second anti-slip layer is provided on the inner surfaces of both the first half-ring and the second half-ring 2, and the thickness of the second anti-slip layer is less than or equal to the height of the first protrusion 11 protruding from the inner surface of the first half-ring 1; among them, the height of the first protrusion 11 protruding from the inner surface of the first half-ring 1 is equal to the height of the second protrusion 21 protruding from the inner surface of the second half-ring 2.

[0061] Specifically, the material of the second anti-slip layer can be, for example, rubber.

[0062] In a possible implementation manner, at least two third bushings 31 are provided at intervals at the first end of the third half-ring 3 in the lower limiting part 200. Among them, at least two third bushings 31 are arranged along the axial direction of the third half-ring 3. At least two fourth bushings 41 are provided at intervals at the first end of the fourth half-ring 4 in the lower limiting part 200. Among them, at least two fourth bushings 41 are arranged along the axial direction of the fourth half-ring 4. The third bushings 31 and the fourth bushings 41 in the lower limiting part 200 are finger-jointed to form a communicating second shaft hole, and a second rotating shaft 6 is passed through the second shaft hole.

[0063] In a possible implementation, the connection method between the third half-ring 3 and the fourth half-ring 4 can refer to the connection between the first half-ring 1 and the second half-ring 2. That is, a third bushing 31 and a fourth bushing 41 are respectively arranged at the first ends of the third half-ring 3 and the fourth half-ring 4, and they are rotationally connected by passing through and sleeving a second rotating shaft 6, which is a better rotational connection method. After the second rotating shaft 6 passes through and is sleeved in the second shaft hole formed by the third bushing 31 and the fourth bushing 41, it is necessary to make both ends of the second rotating shaft 6 be clamped with the second shaft hole to prevent the second rotating shaft 6 from falling off. The clamping method can be to thicken both ends of the second rotating shaft 6 by extrusion, or to pass through and set limit pins or limit safety pins at both ends of the second rotating shaft 6, etc.

[0064] In this embodiment, only an exemplary introduction is made to the specific implementation method of clamping both ends of the second rotating shaft 6 with the second shaft hole, rather than restricting the specific implementation method of clamping both ends of the second rotating shaft 6 with the second shaft hole. The specific implementation method of clamping both ends of the second rotating shaft 6 with the second shaft hole can be selected according to actual needs.

[0065] In a possible implementation, a third ring sleeve 32 is arranged on the outer surface of the second end of the third half-ring 3, and a fourth ring sleeve 42 is arranged on the outer surface of the second end of the fourth half-ring 4. Among them, the third ring sleeve 32 and the fourth ring sleeve 42 face each other and are connected by passing through and sleeving a bolt.

[0066] Specifically, the structures of both the third ring sleeve 32 and the fourth ring sleeve 42 can be ear-shaped rings. The forming method of the structures of the third ring sleeve 32 and the fourth ring sleeve 42, for example, can be integrally formed with the third half-ring 3 and the fourth half-ring 4, or can be subsequently welded and connected. When the third ring sleeve 32 and the fourth ring sleeve are connected by a bolt, a gasket can be set to increase the force-bearing area during fastening.

[0067] Based on the above embodiments, the component parts of the limit device of the non-coupling casing elastic centralizer are introduced in detail. Next, combined with Figure 4 The installation method of the limit device of the non-coupling casing elastic centralizer provided by this application will be introduced in detail. Figure 4 This is the installation schematic diagram of the limit device of the non-coupling casing elastic centralizer provided by the embodiment of this application. Figure 2 . As Figure 4 shown, the installation schematic diagram of the limit device of the non-coupling casing elastic centralizer provided by the embodiment of this application includes a casing centralizer 300, an upper limit part 100, a lower limit part 200, and three casings 7A, 7B, 7C. Among them, the three casings 7A, 7B, 7C are placed in sequence from top to bottom.

[0068] Taking these three casings as an example, the installation method of the limit device of the non-coupling casing elastic centralizer will be introduced:

[0069] First, place the lower limit portion 200 around the lower pipe body of the casing 7B and fasten it. The lower limit portion 200 is at a preset distance from the upper pipe body of the casing 7B.

[0070] After that, install the casing centralizer 300 on the casing 7B. Among them, the casing centralizer 300 is clamped between the lower limit portion 200 and the upper limit portion 100.

[0071] Finally, place the upper limit portion 100 around the connection of the upper and lower casings and fasten it, so that the first protrusion and the second protrusion of the upper limit portion 100 are clamped with the chamfer at the joint of the upper and lower pipe bodies. As Figure 4 shown, place the upper limit portion 100 around the upper and lower connections of the casing 7A and the casing 7B and fasten it, and place another upper limit portion 100 around the upper and lower connections of the casing 7B and the casing 7C and fasten it.

[0072] It should be emphasized that the non-coupling casing elastic centralizer limiting device used in this embodiment can directly use the non-coupling casing elastic centralizer limiting device provided by this application. For the specific implementation structure, reference can be made to the relevant content described in the corresponding embodiment of the above device, which will not be elaborated here.

[0073] For the non-coupling casing elastic centralizer limiting device provided by the embodiment of this application, both its upper limit portion and lower limit portion can be placed around the casing, and the casing centralizer can be clamped between the two. Since both the upper limit portion and the lower limit portion can be clamped on the casing, the upper limit portion can prevent the casing centralizer from sliding upward, and the lower limit portion can prevent the casing centralizer from sliding downward. Therefore, the non-coupling casing elastic centralizer limiting device proposed by this application can ensure that the position of the non-coupling casing elastic centralizer remains fixed, avoiding the problem that the entire casing string cannot be centered due to a large sliding distance of the casing centralizer, and ensuring the cementing quality.

[0074] In the description of this application, it should be understood that the terms "first" and "second" are only used to distinguish each embodiment, and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of this application, the meaning of "a plurality" is at least two, such as two, three, etc., unless otherwise specifically defined.

[0075] In the specification provided here, a large number of specific details are described. However, it can be understood that the embodiments of the invention can be practiced without these specific details. In some instances, well-known structures and technologies are not shown in detail so as not to obscure the understanding of this specification.

[0076] Similarly, it should be understood that, for the purpose of streamlining the present disclosure and facilitating the understanding of one or more of the various inventive aspects, in the foregoing description of the exemplary embodiments of the invention, the various features of the invention are sometimes grouped together into a single embodiment, figure, or description thereof. However, the disclosed apparatus should not be construed as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Rather, as reflected in the following claims, the inventive aspects lie in less than all of the features of the single foregoing disclosed embodiment. Thus, the claims following the detailed description are hereby expressly incorporated into the detailed description, with each claim standing on its own as a separate embodiment of the invention.

[0077] Those skilled in the art will appreciate that the components in the apparatus of the embodiments can be adaptively changed and disposed in one or more apparatuses different from the embodiments. The components in the embodiments can be combined into one component, and in addition, they can be divided into multiple sub-components. Except that at least some of such features are mutually exclusive, any combination can be used to combine all the features disclosed in this specification (including the accompanying claims, abstract, and drawings) and all the components of any apparatus so disclosed. Unless otherwise expressly stated, each feature disclosed in this specification (including the accompanying claims, abstract, and drawings) can be replaced by an alternative feature that provides the same, equivalent, or similar purpose.

[0078] In addition, those skilled in the art will be able to understand that, although some of the embodiments described herein include certain features included in other embodiments rather than other features, the combination of the features of different embodiments means that it is within the scope of the invention and forms different embodiments. For example, in the following claims, any one of the claimed embodiments can be used in any combination. The various component embodiments of the invention can be implemented in hardware, or in their combination.

[0079] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application and are not intended to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the various embodiments of the present application.

Claims

1. An anti-coupling casing elastic centralizer limiting device, characterized in that, Including: an upper limit portion and a lower limit portion; The upper limit portion includes a first half-ring and a second half-ring. The first end of the first half-ring is rotatably connected to the first end of the second half-ring. The second end of the first half-ring and the second end of the second half-ring are connected by bolts. The first half-ring and the second half-ring are joined to form a hoop structure; The lower limit portion includes a third half-ring and a fourth half-ring. The first end of the third half-ring is rotatably connected to the first end of the fourth half-ring. The second end of the third half-ring and the second end of the fourth half-ring are connected by bolts. The third half-ring and the fourth half-ring are joined to form a hoop structure; A casing centralizer is arranged between the upper limit portion and the lower limit portion. The upper limit portion is used to limit the upper edge of the casing centralizer from moving, and the lower limit portion is used to limit the lower edge of the casing centralizer from moving; The upper limit portion, the lower limit portion, and the casing centralizer are all detachably arranged on the outer side of the casing; A first protrusion is arranged on the inner ring surface of the first half-ring, and a second protrusion is arranged on the inner surface of the second half-ring. The first protrusion and the second protrusion face each other and are used to clamp at the joint of the upper and lower pipe bodies of the casing. A first anti-slip layer is arranged on the inner surface of the lower limit portion; The first protrusion is a long strip protrusion arranged along the arc of the inner surface of the first half-ring, and the second protrusion is a long strip protrusion arranged along the arc of the inner surface of the second half-ring. The first protrusion and the second protrusion are clamped with the groove formed by the chamfer at the connection of the upper and lower casings; The first protrusion is formed by the first half-ring protruding from the outer surface to the inner surface, and the second protrusion is formed by the second half-ring protruding from the outer surface to the inner surface; A second anti-slip layer is arranged on the inner surfaces of both the first half-ring and the second half-ring. The thickness of the second anti-slip layer is less than or equal to the height of the first protrusion protruding from the inner surface of the first half-ring; Wherein, the height of the first protrusion protruding from the inner surface of the first half-ring is equal to the height of the second protrusion protruding from the inner surface of the second half-ring.

2. The device according to claim 1, characterized in that, At least two first bushings are arranged at intervals at the first end of the first half-ring, and at least two of the first bushings are arranged along the axial direction parallel to the axis of the first half-ring; At least two second bushings are arranged at intervals at the first end of the second half-ring, and at least two of the second bushings are arranged along the axial direction parallel to the axis of the second half-ring; Wherein, the first bushings and the second bushings are finger-jointed to form a connected first shaft hole, and a first rotating shaft is arranged in the first shaft hole.

3. The device according to claim 2, characterized in that, A first ring sleeve is arranged on the outer surface of the second end of the first half-ring, and a second ring sleeve is arranged on the outer surface of the second end of the second half-ring. The first ring sleeve and the second ring sleeve face each other and are connected by bolts passing through; 4. The device according to claim 2, characterized in that, At least two third bushings are arranged at intervals at the first end of the third half-ring, and at least two of the third bushings are arranged along the axial direction of the third half-ring; At least two fourth bushings are arranged at intervals at the first end of the fourth half-ring, and at least two of the fourth bushings are arranged along the axial direction of the fourth half-ring; Wherein, the third bushing and the fourth bushing are finger-jointed to form a connected second shaft hole, and a second rotating shaft is disposed through the second shaft hole.

5. The device according to claim 2, characterized in that, A third collar is disposed on an outer surface of a second end of the third half-ring, and a fourth collar is disposed on an outer surface of a second end of the fourth half-ring. The third collar and the fourth collar are opposite to each other and are connected by a bolt passing through.

6. The device according to claim 1, wherein The first anti-slip layer is a rubber layer, and anti-slip lines are disposed on a surface of the first anti-slip layer.

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