A casing centralizer for oil exploration

Abstract

The utility model provides a casing centralizer for oil exploitation relates to casing centralizer for oil exploitation field, including centralizer subassembly, including hoop, be used for elastic support's arc elastic sheet, and be used for the concave seat and convex block of connection, auxiliary support subassembly is used for the auxiliary centralizer subassembly slide, auxiliary support subassembly includes box body, and the support rod of box body inner chamber sliding connection, the utility model discloses the cooperation of centralizer subassembly and auxiliary support subassembly has effectively solved the local stress concentration problem of traditional elastic centralizer, two group hoop structure cooperation upper and lower distribution's arc elastic sheet, make centralizer can even disperse stress when operating in the well, auxiliary support subassembly passes through the rolling contact of gyro wheel and well wall, has reduced the slide resistance, and through the elastic buffer effect of spring, makes centralizer can self -adaptation adjustment support degree when passing through well diameter change area, has guaranteed that the casing keeps the central state under the complex well condition all the time.

Description

Technical Field

[0001] This utility model belongs to the field of casing centralizers for oil development, specifically a casing centralizer for oil development. Background Technology

[0002] Casing centralizers are key equipment used to fix the position of casings in oil and gas extraction. Their function is to ensure that the casing is centered in the wellbore, prevent the casing from sticking to the wall and causing uneven distribution of cement, thereby improving cementing quality and extraction safety. Their structure must meet the requirements of pressure resistance, wear resistance and adaptability to complex well conditions. Casing centralizers are mainly divided into three categories according to their structural materials and applicable scenarios: rigid centralizers, elastic centralizers and semi-rigid centralizers. Elastic centralizers typically employ an elastic ball cage structure design, enabling them to automatically adapt to the well diameter. Therefore, they are widely used in oil extraction. Their structure usually consists of a clamp and spring plates. The spring plates are arranged in a spiral or ring shape around the clamp. During insertion, the spring plates are compressed by the well wall, causing elastic deformation and reducing the overall outer diameter of the centralizer for smooth insertion. Once at the designated position, the spring plates recover their deformation, pushing the casing to the center of the wellbore. However, traditional elastic centralizers typically rely solely on the arc-shaped spring plates around the clamp for support and guidance during insertion. This method is prone to localized stress concentration when the arc-shaped spring plates deform, leading to accelerated wear and affecting the centralizer's service life and centralizing effect. Furthermore, in complex well conditions, such as large well diameter variations or irregular protrusions on the well wall, it is difficult to ensure the casing remains centered in the wellbore.

[0003] In summary, this utility model provides a casing centralizer for oilfield development to solve the above-mentioned problems. Utility Model Content

[0004] To solve the above-mentioned technical problems, this utility model provides the following technical solution: A casing centralizer for oil extraction includes a centralizer assembly comprising a clamp, an arc-shaped spring for elastic support, and a concave seat and a convex block for connection. An auxiliary support assembly is used to assist the centralizer assembly in sliding down. The auxiliary support assembly includes a housing, a support rod slidably connected to the inner cavity of the housing, a support seat located outside the housing, a roller located inside the support seat, and a spring located inside the housing. The surface of the clamp is provided with a threaded hole, and both ends of the bow-shaped spring are provided with fixing bolts. One end of the fixing bolt passes through the bow-shaped spring and extends into the inner cavity of the threaded hole, and is threadedly connected to the inner cavity of the threaded hole.

[0005] Furthermore, in this utility model, the clamp is provided in two sets, located at the upper and lower ends of the bow-shaped spring piece respectively, and the clamp includes a left half and a right half.

[0006] Furthermore, in this utility model, the concave seat is fixed at both ends of the left half, the convex block is fixed at both ends of the right half, and the convex block extends into the inner cavity of the concave seat and is inserted into the inner cavity of the concave seat.

[0007] Furthermore, in this utility model, the box body is fixedly connected to the clamp, one end of the support rod extends into the inner cavity of the box body, and the other end of the support rod is fixedly connected to the support base.

[0008] Furthermore, in this invention, the roller is rotatably connected to the inner cavity of the support seat via a bearing, and the two ends of the spring are fixedly connected to the inner wall of the box and the support rod, respectively.

[0009] Beneficial effects: This utility model has the following beneficial effects: This invention effectively solves the problem of localized stress concentration in traditional elastic centralizers through the coordinated operation of the centralizer assembly and the auxiliary support assembly. The two sets of clamping structures, together with the upper and lower distributed bow-shaped springs, enable the centralizer to evenly distribute the force during downhole operations, avoiding excessive wear of the springs caused by single-point contact. The auxiliary support assembly reduces the sliding resistance through the rolling contact between the rollers and the well wall, and through the elastic buffering effect of the springs, it enables the centralizer to adaptively adjust the support force when passing through areas with varying well diameters. This not only extends the service life of the centralizer but also ensures that the casing remains centered under complex well conditions, thereby significantly improving cementing quality and production safety. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of the main structure of this utility model; Figure 2 This is a schematic diagram of the separated state structure of the clamp of this utility model; Figure 3 This is a schematic diagram of the connection structure between the right half of the present invention and the convex block; Figure 4 This is a schematic diagram of the separated structure of the auxiliary support component of this utility model.

[0011] In the picture: 100. Centralizer assembly; 110. Clamp; 111. Left half; 112. Right half; 120. Bow-shaped spring; 130. Concave seat; 140. Convex block; 150. Fixing bolt; 160. Threaded hole; 200. Auxiliary support assembly; 210. Box body; 220. Support rod; 230. Support base; 240. Roller; 250. Spring. Detailed Implementation

[0012] To better understand the technical content of this utility model, specific embodiments are described below in conjunction with the accompanying drawings. Various aspects of this utility model are described in this disclosure with reference to the accompanying drawings, which illustrate numerous illustrative embodiments. The embodiments of this disclosure are not necessarily defined to include all aspects of this utility model. It should be understood that the various concepts and embodiments described above, as well as those described in more detail below, can be implemented in any of many ways, because the concepts and embodiments disclosed in this utility model are not limited to any particular implementation. Furthermore, some aspects of this utility model can be used alone or in any suitable combination with other aspects disclosed in this utility model.

[0013] Example 1 like Figure 1-4 As shown, this is the first embodiment of the present invention. This embodiment provides a casing centralizer for oil drilling, including a centralizer assembly 100, which includes a clamp 110, an arc-shaped spring 120 for elastic support, and a concave seat 130 and a convex block 140 for connection. An auxiliary support assembly 200 is used to assist the centralizer assembly 100 in sliding down. The auxiliary support assembly 200 includes a housing 210, a support rod 220 slidably connected to the inner cavity of the housing 210, a support seat 230 located outside the housing 210, a roller 240 located inside the support seat 230, and a spring 250 located inside the housing 210. The surface of the clamp 110 is provided with a threaded hole 160. Both ends of the arc-shaped spring 120 are provided with fixing bolts 150. One end of the fixing bolt 150 passes through the arc-shaped spring 120 and extends into the inner cavity of the threaded hole 160, and is threadedly connected to the inner cavity of the threaded hole 160.

[0014] like Figure 1-4 As shown, the clamp 110 is configured in two sets. The bow-shaped spring 120 is connected to the threaded hole 160 on the surface of the clamp 110 by the fixing bolt 150, which enhances the overall stability and reduces the shaking or twisting of the bow-shaped spring 120 during deformation. The auxiliary support assembly 200 includes a roller 240 and a support base 230. The roller 240 is rotatably connected by a bearing and can roll on the well wall instead of sliding, reducing frictional resistance. The support rod 220 is slidably connected to the housing 210 and forms a telescopic structure with the spring 250, which enables the assembly to dynamically respond to changes in well diameter. The setting of the roller 240 enables a smooth transition at protrusions or irregularities on the well wall. The spring 250 provides elastic adaptation and, together with the restoring force of the bow-shaped spring 120, makes it easier for the casing to remain in the center of the wellbore under various well conditions.

[0015] Example 2 Reference Figure 1-4 This is the second embodiment of the present invention, which is based on the previous embodiment.

[0016] In this embodiment, two sets of clamps 110 are provided, located at the upper and lower ends of the bow-shaped spring 120 respectively. The clamps 110 include a left half 111 and a right half 112.

[0017] The concave seat 130 is fixed to both ends of the left half 111, and the convex block 140 is fixed to both ends of the right half 112. The convex block 140 extends into the inner cavity of the concave seat 130 and is inserted into the inner cavity of the concave seat 130.

[0018] The box body 210 is fixedly connected to the clamp 110, one end of the support rod 220 extends into the inner cavity of the box body 210, and the other end of the support rod 220 is fixedly connected to the support base 230.

[0019] The roller 240 is rotatably connected to the inner cavity of the support base 230 via a bearing, and the two ends of the spring 250 are fixedly connected to the inner wall of the box 210 and the support rod 220, respectively.

[0020] like Figure 1-4 As shown, the left half 111 and the right half 112 are respectively placed on both sides of the sleeve, so that the convex block 140 and the concave seat 130 are positioned correspondingly. The convex block 140 is inserted into the inner cavity of the concave seat 130 to ensure precise alignment. The convex block 140 and the concave seat 130 have through holes, through which a suitable pin is inserted, so that the left half 111 and the right half 112 are firmly fixed together, thus forming a complete clamp 110. After the clamp 110 is formed, it can stabilize the bow-shaped spring 120. The supporting function places the bow-shaped spring 120 in a suitable position, so that one end of the fixing bolt 150 passes through the bow-shaped spring 120 and extends into the inner cavity of the threaded hole 160 on the surface of the clamp 110. By rotating the fixing bolt 150, it is tightly threadedly connected to the inner cavity of the threaded hole 160, further strengthening the connection between the bow-shaped spring 120 and the clamp 110. The connection method of the bow-shaped spring 120 through the fixing bolt 150 makes it easy to replace the severely worn bow-shaped spring 120 in subsequent use. After the housing 210 is fixedly connected to the clamp 110, one end of the support rod 220 enters the inner cavity of the housing 210, and the other end is fixed to the support seat 230. The roller 240 rotates in the inner cavity of the support seat 230 through the bearing. The two ends of the spring 250 are connected to the inner wall of the housing 210 and the support rod 220 respectively, so that the entire casing centralizer can better adapt to the deformation and displacement of the casing during the oil extraction process and play an effective centralizing role.

[0021] In use, first, the clamp 110 is placed on the designated position outside the sleeve to provide support for subsequent components. Then, the bow-shaped spring 120 is placed in the appropriate position, one end of the fixing bolt 150 is passed through the bow-shaped spring 120 and screwed into the inner cavity of the threaded hole 160 on the surface of the clamp 110. By rotating the fixing bolt 150, it is tightly connected with the threaded hole 160, thereby strengthening the connection between the bow-shaped spring 120 and the clamp 110. If the bow-shaped spring 120 is severely worn during subsequent use, it can be easily replaced. The housing 210 is directly connected to the clamp 110. One end of the support rod 220 slides in the inner cavity of the housing 210, and the other end is fixed to the support seat 230. The roller 240 in the inner cavity of the support seat 230 rotates through the bearing, converting the sliding friction between the casing and the well wall into rolling friction. The two ends of the spring 250 are fixed to the inner wall of the housing 210 and the support rod 220, respectively. When the well diameter expands, the spring 250 pushes the support rod 220 to extend, so that the roller 240 is close to the well wall. When the well diameter shrinks, the pressure of the well wall forces the support rod 220 to retract into the housing 210, and the spring 250 is compressed and stores energy. During the casing lowering process, the roller 240 of the auxiliary support assembly 200 contacts the well wall, and the rolling greatly reduces the sliding resistance. The spring 250 adjusts the support force in real time to adapt to the irregular shape of the wellbore and avoid jamming. The bow-shaped spring 120 continuously provides radial elastic support to ensure that the casing remains centered.

[0022] All standard parts used in this application can be purchased from the market, and can be customized according to the description and drawings. The specific connection methods of each part adopt conventional methods such as bolts, rivets, and welding that are mature in the prior art. The machinery, parts and equipment adopt conventional models in the prior art. The control method is automatic control through a controller. The control circuit of the controller can be implemented by simple programming by those skilled in the art and is common knowledge in the field. Since this application is mainly used to protect mechanical devices, the control method and circuit connection will not be explained in detail in this application.

[0023] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Those skilled in the art to which this invention pertains can make various modifications and refinements without departing from the spirit and scope of the present invention. Therefore, the scope of protection of this invention shall be determined by the claims.

Claims

1. A casing centralizer for oil extraction, characterized in that: include, The centralizer assembly (100) includes a clamp (110), an arc-shaped spring (120) for elastic support, and a concave seat (130) and a convex block (140) for connection. An auxiliary support assembly (200) is used to assist the straightener assembly (100) in sliding down. The auxiliary support assembly (200) includes a housing (210), a support rod (220) slidably connected to the inner cavity of the housing (210), a support seat (230) located outside the housing (210), a roller (240) located in the inner cavity of the support seat (230), and a spring (250) located in the inner cavity of the housing (210). The surface of the clamp (110) is provided with a threaded hole (160), and both ends of the bow-shaped spring (120) are provided with fixing bolts (150). One end of the fixing bolt (150) passes through the bow-shaped spring (120) and extends into the inner cavity of the threaded hole (160), and is threadedly connected to the inner cavity of the threaded hole (160).

2. The casing centralizer for oil extraction as described in claim 1, characterized in that: The clamp (110) is provided in two sets, located at the upper and lower ends of the bow-shaped spring (120) respectively. The clamp (110) includes a left half (111) and a right half (112).

3. The casing centralizer for oil extraction as described in claim 1, characterized in that: The concave seat (130) is fixed at both ends of the left half (111), and the convex block (140) is fixed at both ends of the right half (112). The convex block (140) extends into the inner cavity of the concave seat (130) and is inserted into the inner cavity of the concave seat (130).

4. The casing centralizer for oil extraction as described in claim 1, characterized in that: The box body (210) is fixedly connected to the clamp (110), one end of the support rod (220) extends into the inner cavity of the box body (210), and the other end of the support rod (220) is fixedly connected to the support seat (230).

5. The casing centralizer for oil extraction as described in claim 1, characterized in that: The roller (240) is rotatably connected to the inner cavity of the support base (230) via a bearing, and the two ends of the spring (250) are fixedly connected to the inner wall of the box (210) and the support rod (220) respectively.

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