An anchor pressure adjustable hydraulic anchor

Abstract

The present invention relates to the technical field of downhole tools and hydraulic anchor equipment in petroleum engineering, and particularly relates to an adjustable anchoring pressure hydraulic anchor. The hydraulic anchor includes a body with a spherical installation cavity, multiple groups of elastic anchor claws, a universal barrel core, and a flexible diaphragm. A hydraulic cavity is arranged inside the universal barrel core, the flexible diaphragm is fixed on the outside, and the elastic anchor claws are driven through hydraulic through holes. Under hydraulic drive, the flexible diaphragm expands to push the elastic anchor claws out to achieve anchoring. The universal barrel core allows angular deflection, enhancing the adaptability to curved or irregular wellbores. A flexible belt connects the universal barrel core and the body to adapt to offsets, and a limiting ring is provided to prevent over-expansion from affecting the operation. The upper connection barrel and the body are detachably and sealedly connected, facilitating maintenance. This design solves the problem of poor angle adaptability of traditional rigid structure hydraulic anchors under complex geological conditions, improves the anchoring stability and environmental adaptability, and is applicable to various complex downhole conditions.

Description

Technical Field

[0001] The present invention relates to the technical field of downhole tools and hydraulic anchor equipment in petroleum engineering, and particularly relates to an adjustable anchoring pressure hydraulic anchor. Background Art

[0002] The information disclosed in the background art of the present invention is only intended to increase the understanding of the overall background of the present invention, and is not necessarily regarded as an admission or an implication in any form that this information constitutes the prior art already known to those of ordinary skill in the art.

[0003] Hydraulic anchors are widely used in the oil and gas extraction industry. They are mainly used to make the rigid anchor claw structure extend and fix on the inner wall of the casing through hydraulic drive in the downhole environment, so as to provide stable support or positioning functions. The design of such hydraulic anchors usually relies on a rigid structure to achieve its functions, that is, the anchor claw part is made of a material with higher hardness, and its telescopic action is controlled by a hydraulic system to achieve the purpose of anchoring.

[0004] In the prior art, a large number of improved designs have been made for the problems of sand control or sand blocking. For example, in patent CN113445949 B, for the technical problem of "conducting hydraulic force while blocking foreign objects of any particle size", through technical means such as "the groove area between the elastic film 10 and the porous limiting plate 9 forms a hydraulic conduction cavity", to achieve the technical effect of "being able to block foreign objects such as particles of any particle size while effectively conducting hydraulic force to ensure the normal operation of the hydraulic anchor mechanism and complete the anchoring of the target pipe string".

[0005] However, in actual applications, especially in the curved well sections under complex geological conditions, the traditional hydraulic anchor has poor angle adaptability. Due to the use of a rigid structure, it is difficult to adjust according to the actual geometric shape of the wellbore when the wellbore has a high curvature or local protrusions and depressions, or when the wellbore is curved or has an irregular shape. This results in the inability to achieve a tight fit between the anchor claws and the casing wall, thereby affecting the anchoring effect.

[0006] Therefore, in view of the above existing problems, there is an urgent need for a new design scheme of a hydraulic anchor to overcome the limitations brought by the rigid structure in the prior art, have better angle adaptability and environmental adaptability, and be able to work stably and reliably under various complex downhole conditions. Summary of the Invention

[0007] Aiming at the problems existing in the prior art, the purpose of the present invention is to provide an adjustable anchoring pressure hydraulic anchor, aiming to solve the problems that most existing hydraulic anchors adopt a rigid structure, and in the curved well section, it is impossible to achieve angle adaptability at the same time, it is difficult to fit the casing wall, resulting in anchoring failure and poor environmental adaptability.

[0008] To achieve the above object, the present invention adopts the following technical solutions:

[0009] An anchor pressure adjustable hydraulic anchor, comprising a body, on the side wall of which a plurality of groups of elastic anchor claws are evenly installed;

[0010] The body is a spherical cylindrical shell with a spherical installation cavity inside. An upper connection cylinder is arranged at the top of the body. A suitable universal cylinder core is installed in the installation cavity of the body to realize angle deflection. A lower connection cylinder is arranged at the lower end of the universal cylinder core. A hydraulic cavity communicating with the upper connection cylinder and the lower connection cylinder is opened in the universal cylinder core;

[0011] A flexible belt is connected between the top of the universal cylinder core and the body to realize elastic connection;

[0012] A plurality of groups of hydraulic through holes corresponding to the elastic anchor claws are evenly distributed on the spherical side wall of the universal cylinder core;

[0013] A flexible diaphragm is fixed on the outer side of the spherical side wall of the universal cylinder core, which is used to cooperate with the hydraulic through holes to form an elastic hydraulic channel with self-adaptive ability and push the elastic anchor claws to extend to realize anchoring.

[0014] Preferably, an expansion part for adapting to the angle deflection of the lower connection cylinder is arranged at the lower end of the spherical installation cavity of the body.

[0015] Preferably, a limiting ring is arranged on the outer side of the flexible belt in the spherical installation cavity of the body to limit the expansion range of the flexible belt.

[0016] Preferably, the upper connection cylinder and the body are detachably and sealingly connected;

[0017] A base is arranged at the lower end of the upper connection cylinder, and the base and the body are connected by a flange.

[0018] Preferably, the limiting ring is fixedly arranged at the bottom of the base;

[0019] A sealing gasket is arranged between the base and the body.

[0020] Preferably, the hydraulic cavity is a spherical hydraulic cavity; a plurality of positioning grooves corresponding to the hydraulic through holes are arranged on the inner side wall of the installation cavity of the body to realize the pre-guided positioning of the deformation of the flexible diaphragm and provide a deformation space for the flexible diaphragm, so as to provide a flow space for the hydraulic fluid.

[0021] Preferably, the flexible belt is detachably and sealingly connected with both the universal cylinder core and the body;

[0022] The upper and lower ends of the flexible belt are respectively provided with an upper mounting ring and a lower mounting ring, and the upper mounting ring and the lower mounting ring are respectively threadedly connected to the universal barrel core and the body.

[0023] Preferably, the flexible diaphragm is detachably and sealingly connected to the universal barrel core;

[0024] The upper and lower ends of the flexible diaphragm are respectively provided with corresponding upper press-fitting parts and lower press-fitting parts. The universal barrel core is provided with corresponding upper press-fitting grooves and lower press-fitting grooves. The upper press-fitting grooves and the lower press-fitting grooves are correspondingly installed with adapted upper press-fitting rings and lower press-fitting rings, and the upper press-fitting rings and the lower press-fitting rings are respectively threadedly connected to the upper press-fitting grooves and the lower press-fitting grooves.

[0025] Preferably, the body is provided with a guide hole for installing the elastic anchor claw, and the elastic anchor claw is provided with a piston adapted to be installed in the guide hole;

[0026] A counterbore is opened near the outer end of the guide hole, and a limiting ring plate is fixedly installed in the counterbore. A spring sleeved on the elastic anchor claw is arranged between the limiting ring plate and the piston. The outer end of the elastic anchor claw is provided with an anchoring end located outside the limiting ring plate and adapted to the counterbore for increasing the anchoring area;

[0027] The limiting ring plate is used for supporting the spring to realize the reset of the elastic anchor claw and for limiting the stroke of the anchoring end.

[0028] Preferably, a modular assembly design that supports the assembly and use of two or more anchoring pressure adjustable hydraulic anchors is adopted, and the anchoring pressure adjustable hydraulic anchors are threadedly connected through an upper connecting cylinder and a lower connecting cylinder.

[0029] To more clearly illustrate the present invention, the following content is supplemented:

[0030] When hydraulic fluid is injected into the hydraulic cavity of the universal barrel core, the pressure acts on the flexible diaphragm (or elastic rubber layer), causing it to expand outward through the hydraulic through holes. The expanded flexible diaphragm pushes the piston end of the elastic anchor claw, overcoming the spring resistance, so that the anchoring end extends out of the body and presses against the inner wall of the casing to achieve anchoring. After the hydraulic pressure is released, the spring rebounds to drive the anchor claw to retract.

[0031] When the wellbore bends, the lower connecting cylinder deflects under the action of an external force, driving the universal barrel core to rotate in the spherical installation cavity. The flexible belt compensates for the top offset through elastic deformation to avoid rigid interference.

[0032] After multiple hydraulic anchors are connected in series through the upper and lower connecting cylinders, the universal barrel cores of each module can deflect independently, forming a multi-stage adaptive system, which is applicable to well sections with large curvatures and improves the overall stability.

[0033] Compared with the prior art, although the prior art discloses an elastic film (flexible diaphragm), generally speaking, the body in the present application consists of two parts. An adaptable universal barrel core is installed in the installation cavity therein for realizing angular deflection. The flexible diaphragm in the present application is arranged on the deflectable universal barrel core. Correspondingly, a flexible belt is connected between the top of the universal barrel core and the body for realizing elastic connection, so that the pressure liquid channel is deflectable. As a result, the whole in the present application has a sand prevention effect while realizing anchoring. Moreover, it can deflect a certain angle in the axial direction of the body to adapt to the curved or irregular wellbore shape, which is not recorded in the prior art and has no technical inspiration either.

[0034] The present invention has at least the following beneficial effects:

[0035] By adopting the flexible diaphragm and universal barrel core design, the present invention enables the hydraulic anchor to be flexibly adjusted inside a wellbore with a high degree of curvature or local protrusions and depressions, ensuring close contact between the anchor claws and the casing wall and improving the reliability and stability of anchoring.

[0036] The present invention adopts a modular design, supports the assembly and use of more than two anchoring pressure adjustable hydraulic anchors, can be combined as needed to meet the offset requirements of a larger angle, and is applicable to more complex downhole environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 Schematic diagram of the upper structure of the whole of the present invention;

[0038] Figure 2 Schematic diagram of the lower structure of the whole of the present invention;

[0039] Figure 3 Schematic diagram of the internal structure of the whole of the present invention;

[0040] Figure 4 is Figure 3 Enlarged structural schematic diagram at A in

[0041] Figure 5 Schematic diagram of the split structure of the whole of the present invention;

[0042] Figure 6 Schematic diagram of the structure of the universal barrel core;

[0043] Figure 7 Schematic diagram of the structure of the flexible belt;

[0044] Figure 8 Schematic diagram of the modular combination of the present invention.

[0045] The reference numerals are as follows:

[0046] 100. Upper connecting cylinder; 110. Base; 120. Sealing gasket; 130. Limiting ring; 200. Body; 210. Guide hole; 211. Counterbore; 220. Elastic anchor claw; 221. Piston; 222. Spring; 223. Limiting ring plate; 230. Expansion part; 240. Positioning groove; 300. Lower connecting cylinder; 310. Universal cylinder core; 311. Hydraulic through hole; 312. Upper press-fitting groove; 313. Lower press-fitting groove; 314. Hydraulic cavity; 320. Flexible diaphragm; 321. Lower press-fitting part; 330. Upper press-fitting ring; 340. Lower press-fitting ring; 350. Operating part; 400. Flexible belt; 410. Upper mounting ring; 420. Lower mounting ring. Detailed implementation mode

[0047] The present invention will be further described below in conjunction with specific embodiments and the accompanying drawings.

[0048] Embodiment 1

[0049] Figures 1 to 7 A hydraulically anchored device with adjustable anchoring pressure is presented, including a body 200, and a plurality of groups of elastic anchor claws 220 are evenly installed on the side wall of the body 200;

[0050] The body 200 is a spherical cylindrical shell with a spherical installation cavity inside. An upper connecting cylinder 100 is arranged at the top of the body 200. A suitable universal cylinder core 310 is installed in the installation cavity of the body 200 for realizing angular deflection. A lower connecting cylinder 300 is arranged at the lower end of the universal cylinder core 310. A hydraulic cavity 314 communicating with the upper connecting cylinder 100 and the lower connecting cylinder 300 is opened in the universal cylinder core 310;

[0051] A flexible belt 400 is connected between the top of the universal cylinder core 310 and the body 200 for realizing elastic connection;

[0052] A plurality of groups of hydraulic through holes 311 corresponding to the elastic anchor claws 220 are evenly distributed on the spherical side wall of the universal cylinder core 310;

[0053] A flexible diaphragm 320 or an elastic rubber layer is fixed on the outer side of the spherical side wall of the universal cylinder core 310, which is used to cooperate with the hydraulic through holes 311 to form an elastic hydraulic channel with self-adaptive ability. The flexible diaphragm 320 expands outwards under the drive of hydraulic fluid. Under the cooperation and limitation of the spherical installation cavity, local deformation occurs at the driving end of the elastic anchor claw 220, pushing the elastic anchor claw 220 to extend for realizing anchoring. Since both the flexible belt 400 and the flexible diaphragm 320 need to have elasticity and toughness, corresponding deformations need to occur, and corresponding strengths should be possessed. Therefore, both can be made of elastic rubber material.

[0054] To avoid mechanical interference caused by the deflection of the body 200 on the lower connecting cylinder 300 and increase the deflectable range, an expansion part 230 for adapting to the angular deflection of the lower connecting cylinder 300 is provided at the lower end of the spherical mounting cavity of the body 200.

[0055] The elasticity of the flexible belt 400 is used to adapt to the offset occurring at the top of the universal cylinder core 310 caused by the deflection of the lower connecting cylinder 300. However, as part of the hydraulic flow path, it should not expand without limit. To prevent it from expanding without limit into the spaced area between the spherical mounting cavity and the universal cylinder core 310 due to its own elasticity under the push of the hydraulic fluid, a limiting ring 130 is provided on the outer side of the flexible belt 400 inside the spherical mounting cavity of the body 200.

[0056] The core of this anchor pressure adjustable hydraulic anchor lies in enhancing its adaptability and stability in complex downhole environments by improving the design of the traditional hydraulic anchor and adopting flexible materials and universal structures. Specifically:

[0057] When hydraulic fluid is injected into the hydraulic cavity 314 inside the universal cylinder core 310, these fluids will push the flexible diaphragm 320 to expand outwards through the hydraulic through holes 311 provided on the spherical side wall of the universal cylinder core 310. The expansion of the flexible diaphragm 320 will cause local deformation at the driving end of the elastic anchor claw 220 under the cooperation and limitation of the spherical mounting cavity, thereby pushing the elastic anchor claw 220 to extend out and realizing the anchoring of the inner wall of the casing.

[0058] The design of the universal cylinder core 310 allows a certain degree of angular deflection, which enables the hydraulic anchor to be adjusted according to the actual geometric shape of the wellbore, enhancing its angular adaptability. Especially for curved or irregularly shaped wellbores, this design can ensure a tight fit between the anchor claw and the casing wall, improving the anchoring effect.

[0059] The flexible belt 400 is connected between the top of the universal cylinder core 310 and the body 200, used to adapt to the offset occurring at the top of the universal cylinder core 310 caused by the deflection of the lower connecting cylinder 300, and at the same time, as part of the hydraulic flow path, prevent its unlimited expansion from affecting normal operation.

[0060] Embodiment Two

[0061] Based on the above embodiment, in this embodiment, for the convenience of product installation and maintenance, the upper connecting cylinder 100 and the body 200 are detachably and sealingly connected; the specific connection method is as follows:

[0062] A base 110 is provided at the lower end of the upper connecting cylinder 100. The base 110 and the body 200 are connected by a flange, and a gasket 120 is provided between the base 110 and the body 200. Meanwhile, to maintain the organic unity of the components, the limiting ring 130 is integrally provided at the bottom of the base 110.

[0063] The flexible belt 400 is detachably and sealingly connected to both the universal cylinder core 310 and the body 200; the specific connection method is as follows:

[0064] Upper mounting rings 410 and lower mounting rings 420 are respectively provided at the upper and lower ends of the flexible belt 400, and the upper mounting rings 410 and the lower mounting rings 420 are respectively threadedly connected to the universal cylinder core 310 and the body 200.

[0065] The flexible diaphragm 320 is detachably and sealingly connected to the universal cylinder core 310; the specific connection method is as follows:

[0066] Upper pressing parts and lower pressing parts 321 are respectively provided at the upper and lower ends of the flexible diaphragm 320. The universal cylinder core 310 is provided with corresponding upper pressing grooves 312 and lower pressing grooves 313. Upper pressing rings 330 and lower pressing rings 340 which are adapted are respectively installed in the upper pressing grooves 312 and the lower pressing grooves 313, and the upper pressing rings 330 and the lower pressing rings 340 are respectively threadedly connected to the upper pressing grooves 312 and the lower pressing grooves 313. To facilitate the rotation of the upper pressing rings 330 and the lower pressing rings 340 during installation, an operating part 350 is provided, and the operating part 350 can be in the shape of a groove, a hole, a tooth, etc.

[0067] The hydraulic cavity 314 is a spherical hydraulic cavity 314; a plurality of positioning grooves 240 corresponding to the hydraulic through holes 311 are provided on the inner side wall of the installation cavity of the body 200, which are used to realize the pre - guiding positioning of the deformation of the flexible diaphragm 320 and provide a deformation space for the flexible diaphragm 320, so as to provide a flow space for the hydraulic fluid. It should be noted that the diameter of the positioning groove 240 should be much larger than that of the hydraulic through hole 311, generally about twice that of it, which is to adapt to the movement generated when the universal cylinder core 310 deflects at an angle, so as to provide a hydraulic fluid flow space for the flexible diaphragm 320 extending out of the hydraulic through hole 311 during the deflection process, thereby ensuring smooth and stable hydraulic drive.

[0068] The specific structure of the elastic anchor claw 220 can adopt the existing technology or the following structure:

[0069] The body 200 is provided with a guiding hole 210 for installing the elastic anchor claw 220, and the elastic anchor claw 220 is provided with a piston 221 adapted to be installed in the guiding hole 210;

[0070] A counterbore 211 is provided near the outer end of the guiding hole 210. A limiting ring plate 223 is fixedly installed in the counterbore 211. A spring 222 sleeved on the elastic anchor claw 220 is arranged between the limiting ring plate 223 and the piston 221. An anchoring end located outside the limiting ring plate 223 and adapted to the counterbore 211 is arranged at the outer end of the elastic anchor claw 220, which is used to increase the anchoring area and provide more stable anchoring. The limiting ring plate 223 is used to support the spring 222 to realize the reset of the elastic anchor claw 220 and limit the stroke of the anchoring end.

[0071] Embodiment III

[0072] On the basis of the above embodiments, as shown in this embodiment Figure 8 A modular assembly design that supports the assembly and use of two or more anchoring pressure adjustable hydraulic anchors is adopted. In this embodiment, two modules are taken as an example. Such a design can meet a larger angle of deviation, so as to adapt to a more complex wellbore trajectory (such as an "S" - shaped well). The anchoring pressure adjustable hydraulic anchors are threadedly connected through an upper connecting cylinder 100 and a lower connecting cylinder 300.

[0073] In this specification, each embodiment is described in a progressive manner. The key point of each embodiment is to illustrate the differences from other embodiments. For the same or similar parts among the embodiments, reference can be made to each other.

[0074] Terms such as "upper", "lower", "outer side", "inner side", etc. in the description and claims of the present invention and the above - mentioned drawings are used to distinguish the relative positions and do not need to be qualitatively defined if they exist. It should be understood that such used data can be interchanged under appropriate circumstances so that the embodiments of the present invention described here can be implemented in an order different from those illustrated or described here. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non - exclusive inclusion.

[0075] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art. The general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An anchor pressure adjustable hydraulic anchor, comprising a body, and a plurality of groups of elastic anchor claws are uniformly installed on the side wall of the body; characterized in that: The body is a spherical cylindrical shell with a spherical installation cavity inside, an upper connection cylinder is arranged at the top of the body, a suitable universal cylinder core is installed in the installation cavity of the body for realizing angle deflection, a lower connection cylinder is arranged at the lower end of the universal cylinder core, and a hydraulic cavity communicating with the upper connection cylinder and the lower connection cylinder is opened in the universal cylinder core; A flexible belt is connected between the top of the universal cylinder core and the body for realizing elastic connection; A plurality of groups of hydraulic through holes corresponding to the elastic anchor claws are uniformly distributed on the spherical side wall of the universal cylinder core; A flexible diaphragm is fixed on the outer side of the spherical side wall of the universal cylinder core for cooperating with the hydraulic through holes to form an elastic hydraulic channel with self-adaptive ability and pushing the elastic anchor claws to extend for realizing anchoring.

2. The anchor pressure adjustable hydraulic anchor according to claim 1, characterized in that: An expansion part for adapting to the angle deflection of the lower connection cylinder is arranged at the lower end of the spherical installation cavity of the body.

3. The anchor pressure adjustable hydraulic anchor according to claim 1, characterized in that: A limiting ring is arranged on the inner side wall of the spherical installation cavity of the body outside the flexible belt for limiting the expansion range of the flexible belt.

4. The anchor pressure adjustable hydraulic anchor according to claim 3, characterized in that: The upper connection cylinder and the body are detachably and hermetically connected; A base is arranged at the lower end of the upper connection cylinder, and the base and the body are connected by a flange.

5. The anchor pressure adjustable hydraulic anchor according to claim 4, characterized in that: The limiting ring is fixedly arranged at the bottom of the base; A sealing gasket is arranged between the base and the body.

6. The anchor pressure adjustable hydraulic anchor according to claim 1, characterized in that: The hydraulic cavity is a spherical hydraulic cavity; a plurality of positioning grooves corresponding to the hydraulic through holes are arranged on the inner side wall of the installation cavity of the body for realizing pre-guiding positioning of the deformation of the flexible diaphragm and providing a deformation space for the flexible diaphragm, so as to provide a flow space for the hydraulic fluid.

7. The anchor pressure adjustable hydraulic anchor according to claim 1, characterized in that: The flexible belt is detachably and hermetically connected with both the universal cylinder core and the body; Upper and lower installation rings are respectively arranged at the upper and lower ends of the flexible belt, and the upper and lower installation rings are respectively threadedly connected with the universal cylinder core and the body.

8. The anchor pressure adjustable hydraulic anchor according to claim 1, characterized in that: The flexible diaphragm is detachably and hermetically connected with the universal cylinder core; Upper and lower pressing parts are respectively arranged at the upper and lower ends of the flexible diaphragm, upper and lower pressing grooves are opened in the universal cylinder core, upper and lower pressing rings are correspondingly installed in the upper and lower pressing grooves, and the upper and lower pressing rings are respectively threadedly connected with the upper and lower pressing grooves.

9. The anchor pressure adjustable hydraulic anchor according to claim 1, characterized in that: The body is provided with a guiding hole for installing the elastic anchor claw, and the elastic anchor claw is provided with a piston adaptively installed in the guiding hole; A counterbore is formed at the outer end of the guiding hole, a limiting ring plate is fixedly installed in the counterbore, a spring sleeved on the elastic anchor claw is arranged between the limiting ring plate and the piston, and an anchoring end located outside the limiting ring plate and adapted to the counterbore is arranged at the outer end of the elastic anchor claw for increasing the anchoring area; The limiting ring plate is used for supporting the spring, realizing the reset of the elastic anchor claw, and limiting the stroke of the anchoring end.

10. The adjustable anchoring pressure hydraulic anchor according to any one of claims 1 to 9, characterized in that: A modular assembly design that supports the assembly and use of two or more adjustable anchoring pressure hydraulic anchors is adopted, and the adjustable anchoring pressure hydraulic anchors are threadedly connected through an upper connecting cylinder and a lower connecting cylinder.

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