Centralizer for petroleum drilling

Abstract

The utility model belongs to the technical field of petroleum drilling centralizing, and particularly relates to a centralizer for petroleum drilling, which comprises a landing ring, at least three sliding rails are distributed on the upper surface of the landing ring along a circumferential array, transverse wedge plates are slidably mounted on the upper surfaces of the sliding rails, and arc-shaped plates are fixed at the ends, close to the middle of the landing ring, of the transverse wedge plates. The middle axes of the arc-shaped plates are parallel to the middle axis of the landing ring, the ends, away from the middle of the landing ring, of the transverse wedge plates are inclined faces which are inclined upwards, the inclined faces of the transverse wedge plates are provided with longitudinal wedge plates in an attached mode, the longitudinal wedge plates vertically slide relative to the landing ring, and the sides, away from the landing ring, of the longitudinal wedge plates are fixedly connected with vertical hydraulic cylinders; guide plates are slidably mounted on the two sides of the longitudinal wedge plate, and one ends of the guide plates are fixedly connected to the outer side of the landing ring. Compared with a traditional threaded rod supporting mode, the supporting face adopting hydraulic centralizing is larger, manual adjustment is not needed, and the middle of the drill rod can be conveniently aligned for supporting and centralizing.

Description

Technical Field

[0001] This utility model belongs to the field of oil drilling centralization technology, specifically relating to a centralizer for oil drilling. Background Technology

[0002] Centralizers ensure the verticality and straightness of the wellhead during drilling, which is crucial for improving drilling efficiency and reducing well deviation. Based on the sliding method, there are ball bearing and roller bearing types, but overall they all utilize physical or mechanical principles to achieve the centralizing function.

[0003] For example, some centralizers use chucks or centralizing wheels to adhere tightly to the wellbore wall, providing stable support for the drill string and thus maintaining the verticality and straightness of the wellhead. Other centralizers utilize the principle of gas compression and release, achieving centralization and free movement through expansion and contraction.

[0004] Because of the joints installed between the drill pipes, different thicknesses occur. Existing centralizers often consist of multiple sector plates, with multiple rotatable steel balls installed on the inner side of each sector plate to support the drill pipe. However, using threaded rods to push each sector plate to approach the drill pipe from different directions results in a small support area for the threaded rods, which also requires manual adjustment. It is difficult to align the centralizer with the center of the drill pipe for proper centralization. Therefore, we propose a centralizer for oil drilling. Utility Model Content

[0005] The purpose of this invention is to provide a centralizer for oil drilling. The hydraulic centralizer has a larger support surface than the traditional threaded rod support method, eliminating the need for manual adjustment and making it easy to align and support the drill pipe in the center for centralization.

[0006] The specific technical solution adopted by this utility model is as follows:

[0007] A centralizer for oil drilling includes a landing ring. At least three slide rails are arranged in a circumferential array on the upper surface of the landing ring. A transverse wedge plate is slidably mounted on the upper surface of each slide rail. An arc-shaped plate is fixed to the end of each transverse wedge plate near the center of the landing ring, with the central axis of each arc-shaped plate parallel to the central axis of the landing ring. The ends of each transverse wedge plate away from the center of the landing ring are inclined upwards. A longitudinal wedge plate is fitted onto the inclined surface of each transverse wedge plate, and each longitudinal wedge plate slides vertically relative to the landing ring. A vertical hydraulic cylinder is fixedly connected to the side of each longitudinal wedge plate away from the landing ring. In use, the wellhead of the oil drilling site should first be cleaned, preferably hardened and leveled, before the landing ring is fixed. After the drill pipe is inserted and positioned at the center of the wellhead, the vertical hydraulic cylinder is activated to lift the longitudinal wedge plate. The longitudinal wedge plate slides upward relative to the landing ring. Due to the vertical limitation of the transverse wedge plate by the slide rail, each transverse wedge plate slides along the inclined surface of the adjacent longitudinal wedge plate on the slide rail toward the center of the landing ring until it presses against the drill pipe, achieving close alignment. The support surface of the hydraulic alignment is larger than that of the traditional threaded rod support method, eliminating the need for manual adjustment and facilitating alignment with the center of the drill pipe. Once the joints of different drill pipe thicknesses need to be inserted into the well, the vertical hydraulic cylinder can be controlled to lower the longitudinal wedge plate, and the transverse wedge plates can be moved away from each other. The intervals between the arc plates can be opened to expand the accommodating space of the alignment device, allowing the drill pipe to fall freely.

[0008] Guide plates are slidably installed on both sides of the longitudinal wedge plate. One end of each guide plate is fixedly connected to the outside of the landing ring, and the other side is bent toward the adjacent vertical hydraulic cylinder. The guide plates horizontally support the longitudinal wedge plate, which can relieve the lateral load on the vertical hydraulic cylinder, so that the vertical hydraulic cylinder only needs to extend and retract vertically.

[0009] Each of the longitudinal wedge plates is horizontally fixed with a dust cover at its upper end. The dust cover is suspended directly above the adjacent transverse wedge plate, blocking the contact surface between the transverse and longitudinal wedge plates and reducing the amount of sand and dust falling into the contact surface.

[0010] Each end of the dust cover away from the longitudinal wedge plate is fixed with a saddlebag. The lower edge of the saddlebag is glued to the upper surface of the adjacent transverse wedge plate. The dust cover can rise with the longitudinal wedge plate, stretching the saddlebag and partially sealing the internal space of the dust cover, thereby further improving the dustproof performance.

[0011] Multiple steel balls are rotatably installed on the curved surface of the arc plate near the landing ring. The steel balls can hold the drill rod in place, and the rotation of the steel balls separates the drill rod and the arc plate, reducing friction and allowing the drill rod to maintain vertical and horizontal freedom.

[0012] At least two tension ribs are fixed between the upper surface of the slide rail and the outer side of the adjacent arc plate. There is a gap between the tension ribs and the transverse wedge plate. After the vertical hydraulic cylinder is raised, the arc plate moves away from the vertical hydraulic cylinder and stretches the tension ribs. After the vertical hydraulic cylinder is lowered, the elastic deformation of the tension ribs pulls each arc plate away from each other, opening the gap.

[0013] The technical effects achieved by this utility model are as follows:

[0014] This utility model discloses a centralizer for oil drilling. In use, the wellhead is first cleaned, preferably hardened and leveled. The landing ring is then fixed in the center of the wellhead. After inserting the drill pipe, the vertical hydraulic cylinder is activated to raise the longitudinal wedge plates. The longitudinal wedge plates slide upwards relative to the landing ring. Due to the vertical limitation of the transverse wedge plates by the slide rail, each transverse wedge plate slides along the inclined surface of the adjacent longitudinal wedge plates on the slide rail towards the center of the landing ring until it presses against the drill pipe, achieving close centralization. The hydraulic centralization support surface is larger than that of the traditional threaded rod support method, eliminating the need for manual adjustment and facilitating alignment with the center of the drill pipe for centralization. When drill pipe joints of different thicknesses need to be inserted into the well, the vertical hydraulic cylinder can be controlled to lower the longitudinal wedge plates, moving the transverse wedge plates away from each other. This opens the gaps between the various arc-shaped plates, expanding the centralizer's capacity and allowing the drill pipe to fall freely. Attached Figure Description

[0015] Figure 1 This is a front view of a centralizer for oil drilling according to this utility model;

[0016] Figure 2 This is a front view of the transverse wedge plate of this utility model;

[0017] Figure 3 This is a side view of the longitudinal wedge plate of this utility model;

[0018] Figure 4 This is a rear view of the guide plate of this utility model.

[0019] The attached diagram lists the components represented by each number as follows:

[0020] 1. Grounding ring; 2. Slide rail; 3. Horizontal wedge plate; 4. Arc plate; 5. Longitudinal wedge plate; 6. Vertical hydraulic cylinder; 7. Guide plate; 8. Dust cover; 9. Basket; 10. Steel ball; 11. Tensioner. Detailed Implementation

[0021] To make the objectives and advantages of this utility model clearer, the following detailed description is provided in conjunction with embodiments. It should be understood that the following text is merely used to describe one or more specific embodiments of this utility model and does not strictly limit the scope of protection specifically claimed by this utility model.

[0022] like Figure 1-4As shown, a centralizer for oil drilling includes a landing ring 1. At least three slide rails 2 are arranged in a circumferential array on the upper surface of the landing ring 1. A transverse wedge plate 3 is slidably mounted on the upper surface of each slide rail 2. An arc-shaped plate 4 is fixed to the end of each transverse wedge plate 3 near the center of the landing ring 1. The central axis of each arc-shaped plate 4 is parallel to the central axis of the landing ring 1. The ends of each transverse wedge plate 3 away from the center of the landing ring 1 are inclined upwards. A longitudinal wedge plate 5 is fitted onto the inclined surface of each transverse wedge plate 3. Each longitudinal wedge plate 5 slides vertically relative to the landing ring 1. A vertical hydraulic cylinder 6 is fixedly connected to the side of each longitudinal wedge plate 5 away from the landing ring 1. The vertical hydraulic cylinder 6 can be connected to the hydraulic system of the oil drilling platform to provide a hydraulic power source. Each vertical hydraulic cylinder 6 is signal-connected to the control system of the drilling platform. The panel can use a hydraulic cylinder of model HSG-80 / 45-200-CA-T with a pressure range of 21MPa and a maximum stroke of 450mm. When using it, first clean the wellhead of the oil drilling, preferably harden it and level it. Then fix the landing ring 1 in the center of the wellhead. After inserting the drill pipe, start the vertical hydraulic cylinder 6 to lift the longitudinal wedge plate 5. The longitudinal wedge plate 5 slides upward relative to the landing ring 1. Since the slide rail 2 vertically limits the transverse wedge plate 3, each transverse wedge plate 3 slides along the inclined surface of the adjacent longitudinal wedge plate 5 on the slide rail 2 toward the middle of the landing ring 1 until it presses against the drill pipe to achieve close alignment. The support surface of the hydraulic alignment is larger than that of the traditional threaded rod support method. No manual adjustment is required, and it is convenient to align the drill pipe to the center for support and alignment.

[0023] Once the drill pipe joints of varying thicknesses need to be inserted downhole, the vertical hydraulic cylinder 6 can be controlled to lower the longitudinal wedge plate 5, and the transverse wedge plates 3 can be moved away from each other. This opens the gaps between the various arc-shaped plates 4, expanding the centralizer's accommodating space, allowing the drill pipe to fall freely. In particular, the longitudinal wedge plate 5 slides only vertically relative to the landing ring 1, relieving the lateral load on the vertical hydraulic cylinder 6, allowing the vertical hydraulic cylinder 6 to perform only vertical work.

[0024] For the contact surfaces of the transverse wedge plate 3 and the longitudinal wedge plate 5, lubricating oil can be used for lubrication, especially in the open areas near oil drilling sites where there is a lot of wind and sand, and lubricating oil needs to be added regularly.

[0025] like Figure 1 , Figure 3 and Figure 4 As shown, guide plates 7 are slidably installed on both sides of the longitudinal wedge plate 5. One end of the guide plate 7 is fixedly connected to the outside of the landing ring 1, and the other side is bent towards the adjacent vertical hydraulic cylinder 6. The guide plate 7 horizontally supports the longitudinal wedge plate 5, which can relieve the lateral load on the vertical hydraulic cylinder 6, so that the vertical hydraulic cylinder 6 only needs to extend and retract vertically.

[0026] like Figure 1 and Figure 3As shown, dust covers 8 are horizontally fixed at the upper end of the longitudinal wedge plate 5. The dust covers 8 are suspended directly above the adjacent transverse wedge plate 3, blocking the sand and dust falling into the contact surface between the transverse wedge plate 3 and the longitudinal wedge plate 5.

[0027] like Figure 1 and Figure 3 As shown, a saddlebag 9 is fixed to the end of the dust cover 8 away from the longitudinal wedge plate 5. The saddlebag 9 can be made of silicone film. The lower edge of the saddlebag 9 is glued to the upper surface of the adjacent transverse wedge plate 3. The dust cover 8 can rise with the longitudinal wedge plate 5, stretching the saddlebag 9 and partially sealing the internal space of the dust cover 8, further improving the dustproof performance.

[0028] like Figure 1 and Figure 2 As shown, multiple steel balls 10 are rotatably installed on the arc surface of the arc plate 4 near the landing ring 1. The steel balls 10 can abut against the drill rod, and the rotation of the steel balls 10 separates the drill rod and the arc plate 4, reducing friction and making it easier for the drill rod to maintain vertical and horizontal degrees of freedom.

[0029] like Figure 1 and Figure 2 As shown, at least two tension ribs 11 are fixed between the upper surface of the slide rail 2 and the outer side of the adjacent arc plate 4. There is a gap between the tension ribs 11 and the horizontal wedge plate 3. After the vertical hydraulic cylinder 6 is raised, the arc plate 4 moves away from the vertical hydraulic cylinder 6 and stretches the tension ribs 11. After the vertical hydraulic cylinder 6 is lowered, the elastic deformation of the tension ribs 11 pulls each arc plate 4 away from each other, opening the gap.

[0030] The working principle of this utility model is as follows: When in use, first clean the wellhead of the oil drilling, preferably harden and level it, then fix the landing ring 1 in the center of the wellhead, insert the drill pipe, start the vertical hydraulic cylinder 6 to lift the longitudinal wedge plate 5, the longitudinal wedge plate 5 slides upward relative to the landing ring 1, and due to the vertical limit of the slide rail 2 on the transverse wedge plate 3, each transverse wedge plate 3 slides along the inclined surface of the adjacent longitudinal wedge plate 5 on the slide rail 2 toward the middle of the landing ring 1 until it presses against the drill pipe, thus achieving close alignment. The support surface of the hydraulic alignment is larger than that of the traditional threaded rod support method, and no manual adjustment is required, making it convenient to align the drill pipe to the center for support and alignment.

[0031] Once the drill pipe joints of different thicknesses need to be inserted downhole, the vertical hydraulic cylinder 6 can be controlled to lower the longitudinal wedge plate 5, and the transverse wedge plates 3 can be moved away from each other. The intervals of each arc plate 4 can be opened to expand the centralizer's capacity, allowing the drill pipe to fall freely.

[0032] The above description is merely a preferred embodiment of this utility model. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principle of this utility model, and these improvements and modifications should also be considered within the scope of protection of this utility model. Structures, devices, and operating methods not specifically described or explained in this utility model, unless otherwise specified or limited, shall be implemented using conventional methods in the field.

Claims

1. A centralizer for oil drilling, comprising a grounding ring (1), characterized in that: At least three slide rails (2) are arranged in a circular array on the upper surface of the landing ring (1). A horizontal wedge plate (3) is slidably installed on the upper surface of each slide rail (2). An arc plate (4) is fixed to one end of each horizontal wedge plate (3) near the middle of the landing ring (1). The central axis of each arc plate (4) is parallel to the central axis of the landing ring (1). The end of each horizontal wedge plate (3) away from the middle of the landing ring (1) is an upward inclined surface. A longitudinal wedge plate (5) is attached to the inclined surface of each horizontal wedge plate (3). Each longitudinal wedge plate (5) slides vertically relative to the landing ring (1). A vertical hydraulic cylinder (6) is fixedly connected to one side of each longitudinal wedge plate (5) away from the landing ring (1).

2. A centralizer for oil drilling according to claim 1, characterized in that: Guide plates (7) are slidably installed on both sides of the longitudinal wedge plate (5). One end of the guide plate (7) is fixedly connected to the outside of the landing ring (1), and the other side is bent toward the adjacent vertical hydraulic cylinder (6).

3. A centralizer for oil drilling according to claim 1, characterized in that: Each of the longitudinal wedge plates (5) is horizontally fixed with a dust cover (8), and the dust cover (8) is suspended directly above the adjacent transverse wedge plates (3).

4. A centralizer for oil drilling according to claim 3, characterized in that: The dust cover (8) is fixed with a saddlebag (9) at the end away from the longitudinal wedge plate (5), and the lower edge of the saddlebag (9) is glued to the upper surface of the adjacent transverse wedge plate (3).

5. A centralizer for oil drilling according to claim 1, characterized in that: Multiple steel balls (10) are rotatably installed on the arc surface of the arc plate (4) near the landing ring (1).

6. A centralizer for oil drilling according to claim 1, characterized in that: At least two tension ribs (11) are fixed between the upper surface of the slide rail (2) and the outer side of the adjacent arc plate (4), and a gap is left between the tension ribs (11) and the transverse wedge plate (3).

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