Centralizer for preventing oxidation

Abstract

The application relates to a centralizer for preventing oxidation, which comprises a body made of an anode material, the body is configured in a cylindrical shape, an annular cavity allowing a pipe body to pass through is defined in the body, and a centralizer ring is arranged on the outer wall of the body, a plurality of support ribs are arranged on the outer circumferential surface of the centralizer ring in a circumferential direction, and the support ribs have an outer diameter greater than that of the body. The centralizer for preventing oxidation can effectively prevent the pipe body from tilting downhole during well entering, and improves the oxidation prevention effect of the pipe body.

Description

Technical Field

[0001] This invention relates to a stabilizer for preventing oxidation. Background Technology

[0002] In oil well cementing operations, the casing used for cementing is generally made of steel. Due to the complex environment downhole, the casing is susceptible to environmental influences and may undergo oxidation-reduction reactions, leading to corrosion. Oxidized and corroded casing is prone to crushing and leakage under formation pressure, thus affecting cementing quality and wellbore integrity.

[0003] To avoid this phenomenon, traditional bushing protection primarily involves wrapping an anode block around the bushing. This device works by sacrificing the anode block to protect the cathode bushing during the redox reaction. However, this method is prone to problems during bushing installation; the anode block can easily detach due to friction between the bushing and the exposed hole, resulting in poor oxidation protection. Furthermore, when the bushing vibrates or tilts, the anode block may not adhere properly, further reducing its protective effect. Summary of the Invention

[0004] To address the technical problems described above, this invention aims to provide a centralizer for oxidation prevention. The centralizer of this invention can effectively prevent the downhole casing from tilting during well entry, while simultaneously improving the oxidation prevention effect of the casing.

[0005] According to the present invention, a stabilizer for preventing oxidation is provided, comprising a body made of an anode material, the body being cylindrical in shape, defining an annular cavity within the body for allowing a tube to pass through, and a stabilizer ring disposed on the outer wall of the body, wherein a plurality of support ribs are disposed circumferentially on the outer peripheral surface of the stabilizer ring, the support ribs having an outer diameter larger than that of the body.

[0006] In a preferred embodiment, annular grooves are respectively provided on the outer walls at both ends of the body, and the straightening ring is configured to be inserted into the annular grooves to connect to the body.

[0007] In a preferred embodiment, retaining ring grooves are respectively provided at opposite positions on the inner walls of the annular groove and the straightening ring, and the straightening ring is connected to the body by retaining rings provided in the retaining ring grooves.

[0008] In a preferred embodiment, the retaining ring groove is chamfered, and a boss that can be adapted to the chamfer is formed on the connecting surface where the retaining ring and the retaining ring groove connect.

[0009] In a preferred embodiment, the angle between the chamfer and the bevel is set to 2°-5°.

[0010] In a preferred embodiment, the body and the retaining ring are manufactured using a rolling process, allowing the body and the retaining ring to open along their openings.

[0011] In a preferred embodiment, the support ribs are arranged obliquely on the body.

[0012] In a preferred embodiment, the axial angle between the support rib and the body is set to 20°-40°.

[0013] In a preferred embodiment, the support rib is further provided with screw mounting holes, and the straightening ring is connected to the body by set screws passing through the screw mounting holes.

[0014] In a preferred embodiment, the anode material is a zinc-aluminum alloy. Attached Figure Description

[0015] The invention will now be described with reference to the accompanying drawings.

[0016] Figure 1 A schematic diagram of a centralizer for oxidation prevention according to an embodiment of the present invention is shown.

[0017] Figure 2 for Figure 1 The diagram shown is a schematic of the body of a centralizer used for oxidation prevention.

[0018] Figure 3 for Figure 1 The side view shown is of the retaining ring used for oxidation prevention in a centralizer.

[0019] Figure 4 for Figure 3 The front view of the snap ring is shown.

[0020] Figure 5 for Figure 1 The front view of the centralizing ring of the centralizer used for oxidation prevention is shown.

[0021] Figure 6 for Figure 5 The side view of the straightening ring shown.

[0022] In this application, all drawings are schematic and are used only to illustrate the principles of the invention, and are not drawn to scale. Detailed Implementation

[0023] The invention will now be described with reference to the accompanying drawings.

[0024] Figure 1 A schematic diagram of a centralizer 100 for oxidation prevention according to an embodiment of the present invention is shown. Figure 1As shown, the stabilizer 100 for oxidation prevention includes a body 10. The body 10 is cylindrical. An inner cavity 12 is defined within the body 10, allowing a tube (not shown) to pass through. The body 10 is made of an easily oxidized anodic material. The anodic material may be, for example, a zinc-aluminum alloy. Thus, when the body 10 is fitted onto the tube, the body 10 and the tube can form contact. In this way, when the tube is oxidized and corroded, the tube and the body 10 can respectively act as the anode and cathode, thereby protecting the tube through the body 10 and achieving the purpose of preventing tube oxidation.

[0025] The principle of protecting the cathode by sacrificing the anode to prevent oxidation is well known to those skilled in the art, and a detailed description of it will be omitted here.

[0026] like Figure 1 As shown, a centering ring 20 is also provided on the body 10. The centering ring 20 is sleeved at both ends of the body 10. A plurality of support ribs 40 are provided on the outer wall of the centering ring 20. The support ribs 40 have an outer diameter larger than that of the body 10. Thus, when the operator sleeves the body 10 onto the pipe, the support ribs 40 can abut against the casing (not shown) or the well wall on the outside of the pipe, thereby supporting the pipe 10 and ensuring that the pipe 10 remains vertical and centered on the casing and well wall during the well insertion process.

[0027] Figure 2 for Figure 1 A schematic diagram of the body 10 of the stabilizer 100 for oxidation prevention is shown. Figure 2 As shown, annular grooves 14 are respectively provided at both ends of the main body 10. The annular grooves 14 are configured to have the same size as the straightening ring 20, so that the straightening ring 20 can be inserted into the annular grooves 14 and thus connected to the main body 10. Preferably, the annular grooves 14 are coaxially arranged with the main body 10, so as to ensure that the straightening ring 20 will not tilt during the insertion of the straightening ring 20 into the annular grooves 14.

[0028] Furthermore, a first retaining ring groove 141 is provided within the annular groove 14. Simultaneously, a second retaining ring groove (not shown) is also provided on the inner wall of the straightening ring 20. The second retaining ring groove is configured to be positioned opposite to the first retaining ring groove 141 when the straightening ring 20 is inserted into the annular groove. Thus, the operator can insert the retaining ring 30 (e.g., ...) Figure 1 (As shown) It is positioned between the first retaining ring groove 141 and the second retaining ring groove. This further secures the connection between the body 10 and the straightening ring 20, preventing the straightening ring 20 from sliding or wobbling axially relative to the body 10.

[0029] Figure 3 for Figure 1The side view of the retaining ring 30 of the centralizer 100 for oxidation prevention is shown. Figure 3 As shown, the retaining ring 30 is circular in shape. A boss 32 is provided on the outer wall of the retaining ring 30. The boss 32 is trapezoidal in shape. Chamfers (not shown) are also provided on the first retaining ring groove 141 and the second retaining ring groove, respectively. The chamfers can engage with the boss 32, thereby further fixing the retaining ring 30 to the first retaining ring groove 141 and the second retaining ring groove, preventing the retaining ring 30 from shifting or misaligning, thus affecting the fixing effect of the retaining ring 30.

[0030] Furthermore, the inclination angle of the side of the boss 32 and the chamfer angle are set to 2°-5°. Multiple experiments by the designers have shown that setting the angles within this range allows the retaining ring 30 to achieve a more stable connection.

[0031] Figure 4 for Figure 3 The front view of the retaining ring 30 is shown. Figure 3 As shown, the retaining spring 30 is manufactured using a rolling process, allowing it to open along its opening 34. Therefore, after the body 10 is connected to the pipe, the operator can install the retaining spring 30 onto the body 10 by opening it. Similarly, the body 10 is also manufactured using a rolling process, allowing the operator to install it onto the pipe by opening it. It is easy to understand that compared to the existing axially sleeved installation method, this design effectively simplifies the installation process of the retaining spring 30 and the body 10 when the pipe length is long, thus saving operation time.

[0032] This installation method also allows operators to adjust the inner diameter of the body 10 in real time according to the diameter of the pipe, so that the body 10 can fully connect with the pipe and ensure that the body 10 provides better protection for the pipe.

[0033] Figure 5 for Figure 1 The diagram shows a front view of the centralizing ring 20 of the centralizer 100 for oxidation prevention. Multiple support ribs 40 are provided on the centralizing ring 20, and the multiple support ribs 40 are evenly arranged along the circumference of the centralizing ring 20.

[0034] Figure 6 for Figure 5 The side view of the straightening ring 20 shown. Figure 6As shown, the support rib 40 is arranged obliquely on the straightening ring 20 along the axial direction. This arrangement effectively increases the force between the support rib 40 and the casing or well wall, preventing the support rib 40 from moving relative to the casing or well wall along the axial direction, thereby effectively preventing pipe body deflection and contributing to a more stable straightening effect.

[0035] In a preferred embodiment, the axial angle between the support rib 40 and the body 10 is set to 20°-40°. Field operation practice shows that by setting the inclination angle of the support rib 40 within this range, the support rib 40 can provide a more stable support effect.

[0036] like Figure 6 As shown, each of the support ribs 40 is also provided with a screw mounting hole 45. The straightening ring 20 is connected to the body 10 by a set screw (not shown) passing through the screw mounting hole 45. The set screw, together with the retaining ring 30, can secure the connection between the support ring 20 and the body 10. This further reduces the risk of the straightening ring 20 tilting or falling off.

[0037] The working process of the stabilizer 100 for oxidation prevention according to the present invention is briefly described below.

[0038] The centralizer 100 for oxidation prevention of the present invention is used to connect to the downhole tubing string, serving to centralize and prevent oxidation. During use, the operator first needs to open the body 10 and install it on the tubing to be protected, and adjust the inner diameter of the body 10 according to the tubing to ensure full contact between the body 10 and the tubing.

[0039] Subsequently, the operator can install the retaining ring 30 and press the straightening ring 20 into the ring groove 14, so that the straightening ring 20 is connected to the body 10 through the retaining ring 30. Finally, the set screw is installed to fix the body 10 through the retaining ring 30.

[0040] After the centralizer 100 is installed, the operator can lower the casing and centralizer 100 together into the well. During the lowering process, the support ribs 40 on the centralizer ring 20 can engage with the casing or well wall, thereby achieving a centralizing effect. Once the tubing reaches the designated position, the main body 10 can provide protection, preventing the casing from being oxidized or corroded inside the well.

[0041] Finally, it should be noted that the above description is merely a preferred embodiment of the present invention and does not constitute any limitation on the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A centralizer for preventing oxidation, comprising: The body (10) is made of anode material and is cylindrical in shape. An annular cavity (12) is defined in the body to allow the tube to pass through. Annular grooves (14) are respectively provided on the outer walls at both ends of the body, and a first snap ring groove (141) is provided in the annular groove. A straightening ring (20) is integrally fitted onto the outer wall of the main body. The straightening ring is configured to be inserted into the ring groove. Multiple support ribs (40) are arranged circumferentially on the outer circumferential surface of the straightening ring. The support ribs have a diameter larger than that of the main body. A second retaining ring groove is provided on the inner wall of the straightening ring. A retaining ring is provided, which can be disposed between the first retaining ring groove and the second retaining ring groove, so that the straightening ring can be connected to the body; The body and the retaining ring are made by a rolling process, which allows the body and the retaining ring to open along their openings, and the straightening ring fitted on the body is a complete ring.

2. The stabilizer for oxidation prevention according to claim 1, characterized in that, The circlip groove has a chamfer, and a boss (32) that can be adapted to the chamfer is constructed on the connecting surface where the circlip and the circlip groove are connected.

3. The stabilizer for oxidation prevention according to claim 2, characterized in that, The angle between the chamfer and the bevel is set to 2°-5°.

4. The centralizer for oxidation prevention according to any one of claims 1 to 3, characterized in that, The support ribs are arranged at an angle on the body.

5. The stabilizer for oxidation prevention according to claim 4, characterized in that, The axial angle between the support rib and the body is set to 20°-40°.

6. The centralizer for oxidation prevention according to any one of claims 1 to 3, characterized in that, The support rib is also provided with screw mounting holes (45), and the straightening ring is connected to the body by a set screw passing through the screw mounting hole.

7. The centralizer for oxidation prevention according to any one of claims 1 to 3, characterized in that, The anode material is a zinc-aluminum alloy.

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