Anchoring pressure adjustable hydraulic anchor

Abstract

The invention relates to the technical field of petroleum engineering downhole tools and hydraulic anchor equipment, in particular to an anchoring pressure adjustable hydraulic anchor which comprises a body with a spherical mounting cavity, a plurality of groups of elastic anchor flukes, a universal cylinder core and a flexible diaphragm. A hydraulic cavity is formed in the universal cylinder core, a flexible diaphragm is fixed to the outer side, and the elastic anchor flukes are driven through hydraulic through holes. Under hydraulic driving, the flexible diaphragm expands to push the elastic anchor flukes to stretch out to achieve anchoring. And the universal cylinder core allows angular deflection, so that the adaptability to a bent or irregular shaft is enhanced. The flexible belt is connected with the universal cylinder core and the body to adapt to deviation, and the limiting ring is arranged to prevent excessive expansion from affecting work. The upper connecting cylinder and the body are detachably connected in a sealed mode, and maintenance is convenient. By means of the design, the problem that a traditional rigid structure hydraulic anchor is poor in angle self-adaptive capacity under complex geological conditions is solved, anchoring stability and environmental adaptability are improved, and the hydraulic anchor is suitable for various complex underground conditions.

Description

Technical Field

[0001] The invention relates to the technical field of downhole tools and hydraulic anchor equipment for petroleum engineering, and in particular to a hydraulic anchor with adjustable anchoring pressure. Background Art

[0002] The information disclosed in the background of the invention is only intended to enhance the understanding of the overall background of the invention and should not be necessarily regarded as an acknowledgment or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art.

[0003] Hydraulic anchors are widely used in the oil and gas extraction industry. They are mainly used to extend and fix the rigid anchor claw structure to the inner wall of the casing in the underground environment through hydraulic drive to provide stable support or positioning functions. This type of hydraulic anchor design usually relies on a rigid structure to achieve its function, that is, the anchor claw part is made of a material with a higher hardness, and its extension and retraction movement 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 problem of sand prevention or sand blocking. For example, patent CN113445949 B, for the technical problem of "blocking foreign matter of any particle size while transmitting hydraulic force", adopts technical means such as "forming a hydraulic conduction cavity in the groove area between the elastic film 10 and the porous limiting plate 9" to achieve the technical effect of "being able to block foreign matter such as particles of any particle size while effectively transmitting hydraulic force to ensure the normal operation of the hydraulic anchor mechanism and complete the anchoring of the target pipe string".

[0005] However, in practical applications, especially in curved well sections under complex geological conditions, the traditional hydraulic anchor has poor angle adaptability. Due to the rigid structure, it is difficult to adjust according to the actual geometry of the wellbore when it is highly curved or has local protrusions or depressions, or when it encounters curved or irregular shapes. This results in the inability to achieve a close fit between the anchor claw and the casing wall, which in turn affects the anchoring effect.

[0006] Therefore, in response to the above-mentioned problems, there is an urgent need for a new hydraulic anchor design solution that overcomes the limitations of the rigid structure in the prior art, has better angle adaptability and environmental adaptability, and can work stably and reliably under various complex underground conditions. Summary of the invention

[0007] In view of the problems existing in the prior art, the purpose of the present invention is to provide a hydraulic anchor with adjustable anchoring pressure, aiming to solve the problems that the existing hydraulic anchors mostly adopt a rigid structure, cannot achieve angle adaptation at the same time in curved well sections, are difficult to fit the casing wall, resulting in anchoring failure, and have poor environmental adaptability.

[0008] In order to achieve the above purpose, the present invention adopts the following technical solutions: An anchoring pressure adjustable hydraulic anchor, comprising a body, with a plurality of sets of elastic anchor claws evenly mounted on the side wall of the body; The body is a spherical cylinder shell with a spherical mounting cavity. An upper connecting cylinder is arranged on the top of the body. An adaptable universal cylinder core is installed in the mounting cavity of the body to realize angle deflection. A lower connecting cylinder is arranged at the lower end of the universal cylinder core. A hydraulic cavity communicating with the upper connecting cylinder and the lower connecting cylinder is opened in the universal cylinder core. A flexible belt is connected between the top of the universal cylinder core and the body to achieve elastic connection; 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; 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 hole to form an elastic hydraulic channel with self-adaptive ability and push the elastic anchor claw to extend to achieve anchoring.

[0009] Preferably, the lower end of the spherical mounting cavity of the main body is provided with an expansion portion for adapting to the angular deflection of the lower connecting tube.

[0010] Preferably, a limiting ring is provided on the outer side of the flexible band in the spherical installation cavity of the body to limit the expansion range of the flexible band.

[0011] Preferably, the upper connecting tube and the body are detachably sealed. A base is provided at the lower end of the upper connecting tube, and the base and the body are connected through a flange.

[0012] Preferably, the limiting ring is fixedly arranged at the bottom of the base; A sealing gasket is arranged between the base and the body.

[0013] Preferably, the hydraulic chamber is a spherical hydraulic chamber, and its inner wall is provided with a plurality of positioning grooves corresponding to the hydraulic through holes, for achieving pre-guiding positioning of the deformation of the flexible diaphragm and providing a shaping space for the elastic diaphragm, thereby providing a flow space for the hydraulic fluid.

[0014] Preferably, the flexible belt is detachably sealed to the universal tube core and the body; An upper mounting ring and a lower mounting ring are respectively arranged at the upper end and the lower end of the flexible belt, and the upper mounting ring and the lower mounting ring are respectively threadedly connected with the universal cylinder core and the body.

[0015] Preferably, the flexible diaphragm and the universal cylinder core are detachably sealed. The upper and lower ends of the flexible diaphragm are both provided with corresponding upper press-fitting parts and lower press-fitting parts, and the universal cylinder core is provided with corresponding upper press-fitting grooves and lower press-fitting grooves, and the upper press-fitting grooves and lower press-fitting grooves are correspondingly installed with matching upper press-fitting rings and lower press-fitting rotating rings, and the upper press-fitting rings and lower press-fitting rotating rings are respectively threadedly connected with the upper press-fitting grooves and lower press-fitting grooves.

[0016] 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; The guide hole is provided with a countersunk hole near the outer end, a limiting ring plate is fixedly installed in the countersunk hole, a spring sleeved on the elastic anchor claw is provided between the limiting ring plate and the piston, and an anchoring end located outside the limiting ring plate and adapted to the countersunk hole is provided at the outer end of the elastic anchor claw, so as to increase the anchoring area; The limiting ring plate is used to support the spring, realize the resetting of the elastic anchor claw, and is used to limit the travel of the anchoring end.

[0017] Preferably, a modular assembly design is adopted to support the assembly and use of more than two hydraulic anchors with adjustable anchoring pressures, wherein the hydraulic anchors with adjustable anchoring pressures are threadedly connected to each other via an upper connecting tube and a lower connecting tube.

[0018] In order to explain the present invention more clearly, the following contents are supplemented: When hydraulic fluid is injected into the hydraulic chamber of the universal cylinder core, the pressure acts on the flexible diaphragm (or elastic rubber layer), causing it to expand outward through the hydraulic through hole. The expanded flexible diaphragm pushes the piston end of the elastic anchor claw, overcoming the spring resistance, so that the anchor 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 and drives the anchor claw to retract.

[0019] When the wellbore bends, the lower connecting tube deflects due to external force, driving the universal tube core to rotate in the spherical installation cavity. The flexible belt compensates for the top deviation through elastic deformation to avoid rigid interference.

[0020] After multiple hydraulic anchors are connected in series through upper and lower connecting tubes, the universal tube core of each module can deflect independently to form a multi-level adaptive system, which is suitable for large curvature well sections and improves overall stability.

[0021] Compared with the prior art, although the prior art discloses an elastic film (flexible diaphragm), as a whole, the main body in the present application includes two parts, wherein an adaptable universal core is installed in the installation cavity for realizing angle deflection, and the flexible diaphragm in the present application is arranged on the deflectable universal core, and correspondingly, a flexible belt is connected between the top of the universal core and the main body for realizing elastic connection, so that the pressure liquid channel is deflectable, so that the whole in the present application has a sand control effect while realizing anchoring, and can be deflected at a certain angle in the axial direction of the main body to adapt to the curved or irregular wellbore shape, which is not recorded in the prior art and has no technical inspiration.

[0022] The present invention has at least the following beneficial effects: The present invention adopts a flexible diaphragm and a universal core design, so that the hydraulic anchor can be flexibly adjusted inside a wellbore with a high degree of curvature or with local protrusions or depressions, thereby ensuring close contact between the anchor claw and the casing wall and improving the reliability and stability of anchoring.

[0023] The present invention adopts a modular design and supports the assembly and use of more than two hydraulic anchors with adjustable anchoring pressures. The anchors can be combined as needed to meet the requirements of larger angles of displacement and are suitable for more complex underground environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the overall upper structure of the present invention; Figure 2 It is a schematic diagram of the overall lower structure of the present invention; Figure 3 It is a schematic diagram of the overall internal structure of the present invention; Figure 4 for Figure 3 A schematic diagram of the enlarged structure at A in the middle; Figure 5 This is a schematic diagram of the overall split structure of the present invention; Figure 6 It is a structural schematic diagram of the universal cylinder core; Figure 7 is a schematic diagram of the structure of the flexible belt; Figure 8 It is a schematic diagram of the modular combination of the present invention.

[0025] The reference numerals are as follows: 100, upper connecting tube; 110, base; 120, sealing gasket; 130, limiting ring; 200, main body; 210, guide hole; 211, countersunk hole; 220, elastic anchor claw; 221, piston; 222, spring; 223, limiting ring plate; 230, expansion part; 240, positioning groove; 300, lower connecting tube; 310, universal tube core; 311, hydraulic through hole; 312, upper pressure groove; 313, lower pressure groove; 314, hydraulic chamber; 320, flexible diaphragm; 321, lower pressure part; 330, upper pressure ring; 340, lower pressure rotating circle; 350, operating part; 400, flexible belt; 410, upper mounting ring; 420, lower mounting ring. DETAILED DESCRIPTION

[0026] The present invention will be further described below in conjunction with specific embodiments and accompanying drawings.

[0027] Embodiment 1: Figures 1 to 7 A hydraulic anchor with adjustable anchoring pressure is shown, comprising a body 200, on the side wall of which a plurality of groups of elastic anchor claws 220 are evenly mounted; The body 200 is a spherical cylinder shell with a spherical mounting cavity. An upper connecting cylinder 100 is disposed on the top of the body 200. An adaptable universal cylinder core 310 is installed in the mounting cavity of the body 200 for achieving angle deflection. A lower connecting cylinder 300 is disposed 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. A flexible belt 400 is connected between the top of the universal cylinder core 310 and the body 200 to achieve elastic connection; The spherical side wall of the universal cylinder core 310 is evenly distributed with a plurality of groups of hydraulic through holes 311 corresponding to the elastic anchor claws 220; A flexible membrane 320 or an elastic rubber layer is fixed to the outer side of the spherical side wall of the universal cylinder core 310, which is used to cooperate with the hydraulic through hole 311 to form an elastic hydraulic channel with adaptive ability. The flexible membrane 320 expands outward under the drive of the hydraulic fluid, and produces local deformation at the driving end of the elastic anchor claw 220 under the cooperation and limitation of the spherical installation cavity, pushing the elastic anchor claw 220 to extend for anchoring. Since the flexible belt 400 and the flexible membrane 320 are both required to have elasticity and toughness, corresponding deformation, and should have corresponding strength, they can both be made of elastic rubber material.

[0028] In order to prevent the body 200 from mechanically interfering with the deflection of the lower connecting tube 300 and to increase the deflectable range, the lower end of the spherical installation cavity of the body 200 is provided with an expansion portion 230 for adapting to the angular deflection of the lower connecting tube 300 .

[0029] The elasticity of the flexible band 400 is used to accommodate the offset of the top of the universal cylinder core 310 caused by the deflection of the lower connecting cylinder 300, but as part of the hydraulic flow channel, it should not expand indefinitely. In order to prevent the hydraulic fluid from pushing it to expand indefinitely in the interval space between the spherical mounting cavity and the universal cylinder core 310 due to its own elasticity, a limit ring 130 is provided on the outside of the flexible band 400 in the spherical mounting cavity of the main body 200.

[0030] The core of this hydraulic anchor with adjustable anchoring pressure is to improve the design of traditional hydraulic anchors and use flexible materials and universal structures to enhance their adaptability and stability in complex underground environments. Specifically: When hydraulic fluid is injected into the hydraulic chamber 314 in the universal cylinder core 310, the fluid will push the flexible diaphragm 320 to expand outward through the hydraulic through hole 311 provided on the spherical side wall of the universal cylinder core 310. The expansion of the flexible diaphragm 320 will produce local deformation at the driving end of the elastic anchor claw 220 under the matching limit of the spherical installation cavity, thereby pushing the elastic anchor claw 220 to extend and realize anchoring to the inner wall of the casing.

[0031] The universal core 310 design allows a certain degree of deflection, which enables the hydraulic anchor to adjust according to the actual geometry of the wellbore, enhancing its angle adaptability. Especially for curved or irregular wellbores, this design can ensure a close fit between the anchor claw and the casing wall, improving the anchoring effect.

[0032] The flexible band 400 is connected between the top of the universal cylinder core 310 and the body 200 to accommodate the displacement of the top of the universal cylinder core 310 caused by the deflection of the lower connecting cylinder 300 and, as part of the hydraulic flow channel, prevents it from expanding without limit and affecting normal operation.

[0033] Embodiment 2: On the basis of the above embodiment, in this embodiment, in order to facilitate product installation and maintenance, the upper connecting tube 100 and the body 200 are detachably sealed and connected; the specific connection method is as follows: The lower end of the upper connecting tube 100 is provided with a base 110, the base 110 and the body 200 are connected by a flange, and a sealing gasket 120 is provided between the base 110 and the body 200. At the same time, in order to maintain the organic unity of the components, the limiting ring 130 is integrally provided at the bottom of the base 110.

[0034] The flexible belt 400 is detachably sealed to the universal cylinder core 310 and the body 200; the specific connection method is as follows: An upper mounting ring 410 and a lower mounting ring 420 are respectively disposed at the upper end and the lower end of the flexible belt 400 . The upper mounting ring 410 and the lower mounting ring 420 are respectively threadedly connected to the universal barrel core 310 and the body 200 .

[0035] The flexible diaphragm 320 and the universal cylinder core 310 are detachably sealed and connected; the specific connection method is as follows: The upper and lower ends of the flexible diaphragm 320 are both provided with corresponding upper and lower pressing parts 321, and the universal cylinder core 310 is provided with corresponding upper and lower pressing grooves 312 and 313, and the upper and lower pressing grooves 312 and 313 are correspondingly provided with matching upper and lower pressing rings 330 and 340, and the upper and lower pressing rings 330 and 340 are respectively threadedly connected with the upper and lower pressing grooves 312 and 313. In order to facilitate the rotation of the upper and lower pressing rings 330 and 340 during installation, an operating part 350 is provided, and the operating part 350 can be groove-shaped, hole-shaped, or tooth-shaped.

[0036] The hydraulic cavity 314 is a spherical hydraulic cavity 314, and its inner wall is provided with a plurality of positioning grooves 240 corresponding to the hydraulic through hole 311, which are used to realize the pre-guiding positioning of the deformation of the flexible diaphragm 320, and provide a shaping space for the elastic diaphragm, thereby providing a flow space for the hydraulic fluid. It should be noted that the diameter of the positioning groove 240 should be much larger than the hydraulic through hole 311, generally about twice as large, in order to adapt to the movement of the universal cylinder core 310 when the angle deflection occurs, 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.

[0037] The specific structure of the elastic anchor claw 220 can adopt the existing technology, or can adopt the following structure: The body 200 is provided with a guide 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 guide hole 210; The guide hole 210 is provided with a counterbore 211 near the outer end, and a limit ring plate 223 is fixedly installed in the counterbore 211. A spring 222 mounted on the elastic anchor claw 220 is provided between the limit ring plate 223 and the piston 221. The outer end of the elastic anchor claw 220 is provided with an anchor end located outside the limit ring plate 223 and adapted to the counterbore 211, which is used to increase the anchoring area and provide more stable anchoring. The limit ring plate 223 is used to support the spring 222, realize the resetting of the elastic anchor claw 220, and is used to limit the travel of the anchor end.

[0038] Embodiment three: Based on the above embodiments, this embodiment Figure 8 As shown, a modular assembly design is adopted to support the assembly and use of more than two hydraulic anchoring anchors with adjustable anchoring pressure. This embodiment takes two modules as an example. Such a design can meet the requirements of larger angle offsets, thereby adapting to more complex wellbore trajectories (such as "S"-shaped wells). The hydraulic anchors with adjustable anchoring pressure are threadedly connected by an upper connecting tube 100 and a lower connecting tube 300.

[0039] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same and similar parts between the various embodiments can be referenced to each other.

[0040] The terms "upper", "lower", "outer side", "inner side", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish the relative relationship in position if they exist, and do not need to be qualitative. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present invention described here can be implemented in an order other than those illustrated or described here. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions.

[0041] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may 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 rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A hydraulic anchor with adjustable anchoring pressure, comprising a body, on the side wall of which a plurality of sets of elastic anchor claws are evenly mounted; characterized in that: The body is a spherical cylinder shell with a spherical mounting cavity. An upper connecting cylinder is arranged on the top of the body. An adaptable universal cylinder core is installed in the mounting cavity of the body to realize angle deflection. A lower connecting cylinder is arranged at the lower end of the universal cylinder core. A hydraulic cavity communicating with the upper connecting cylinder and the lower connecting cylinder is opened in the universal cylinder core. A flexible belt is connected between the top of the universal cylinder core and the body to achieve elastic connection; 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; 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 hole to form an elastic hydraulic channel with self-adaptive ability and push the elastic anchor claw to extend to achieve anchoring.

2. The hydraulic anchor with adjustable anchoring pressure as claimed in claim 1, characterized in that: The lower end of the spherical installation cavity of the body is provided with an expansion portion for adapting to the angular deflection of the lower connecting tube.

3. The hydraulic anchor with adjustable anchoring pressure according to claim 1, characterized in that: 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.

4. The hydraulic anchor with adjustable anchoring pressure as claimed in claim 3, characterized in that: The upper connecting tube and the body are detachably and hermetically connected; A base is provided at the lower end of the upper connecting tube, and the base and the body are connected through a flange.

5. The hydraulic anchor with adjustable anchoring pressure as claimed in 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 hydraulic anchor with adjustable anchoring pressure according to claim 1, characterized in that: The hydraulic cavity is a spherical hydraulic cavity, and its inner wall is provided with a plurality of positioning grooves corresponding to the hydraulic through holes, which are used to achieve pre-guided positioning of the deformation of the flexible diaphragm and provide a shaping space for the elastic diaphragm, thereby providing a flow space for the hydraulic fluid.

7. The hydraulic anchor with adjustable anchoring pressure according to claim 1, characterized in that: The flexible belt is detachably sealed to the universal tube core and the body; An upper mounting ring and a lower mounting ring are respectively arranged at the upper end and the lower end of the flexible belt, and the upper mounting ring and the lower mounting ring are respectively threadedly connected with the universal cylinder core and the body.

8. The hydraulic anchor with adjustable anchoring pressure according to claim 1, characterized in that: The flexible diaphragm and the universal cylinder core are detachably sealed and connected; The upper and lower ends of the flexible diaphragm are both provided with corresponding upper press-fitting parts and lower press-fitting parts, and the universal cylinder core is provided with corresponding upper press-fitting grooves and lower press-fitting grooves, and the upper press-fitting grooves and lower press-fitting grooves are correspondingly installed with matching upper press-fitting rings and lower press-fitting rotating rings, and the upper press-fitting rings and lower press-fitting rotating rings are respectively threadedly connected with the upper press-fitting grooves and lower press-fitting grooves.

9. The hydraulic anchor with adjustable anchoring pressure according to claim 1, characterized in that: 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; The guide hole is provided with a countersunk hole near the outer end, a limiting ring plate is fixedly installed in the countersunk hole, a spring sleeved on the elastic anchor claw is provided between the limiting ring plate and the piston, and an anchoring end located outside the limiting ring plate and adapted to the countersunk hole is provided at the outer end of the elastic anchor claw, so as to increase the anchoring area; The limiting ring plate is used to support the spring, realize the resetting of the elastic anchor claw, and is used to limit the travel of the anchoring end.

10. The hydraulic anchor with adjustable anchoring pressure according to any one of claims 1 to 9, characterized in that: A modular assembly design is adopted to support the assembly and use of more than two hydraulic anchors with adjustable anchoring pressures, wherein the hydraulic anchors with adjustable anchoring pressures are threadedly connected via an upper connecting tube and a lower connecting tube.

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