Anti-blocking double-hydraulic-pressure hydraulic anchor

Abstract

The invention relates to the technical field of hydraulic anchors, and discloses an anti-blocking double-hydraulic hydraulic anchor which can prevent liquid from entering anchor fluke holes, improve the reliability of the hydraulic anchor and reduce the failure risk caused by sand blocking and water scale. Comprising an anchor body, the two ends of the anchor body are connected with an upper connector and a lower connector, a first hydraulic channel is formed in the middle of the anchor body, multiple sets of second hydraulic channels are formed in the side portion of the anchor body, each second hydraulic channel is provided with a liquid inlet end and a liquid outlet end, a set of anchor fluke holes are formed above each set of second hydraulic channels, and a set of anchor fluke structures are installed at the positions of each set of anchor fluke holes; the anchor fluke structure comprises an anchor fluke part, the anchor fluke part is arranged in the anchor fluke hole, a shell sleeve is arranged on the inner side of the anchor fluke part, and the shell sleeve is arranged on the inner side of the anchor fluke hole in a sealing and covering mode; a pressed part connected with the anchor fluke part is arranged on the shell sleeve; and a sealing part communicated with the liquid outlet end of the second hydraulic channel is mounted at the joint of the shell sleeve and the anchor body, so that after liquid enters the second hydraulic channel, the sealing part expands and seals the joint of the shell sleeve and the anchor body.

Description

Technical Field

[0001] The invention relates to the technical field of hydraulic anchors, and in particular to an anti-stuck double hydraulic hydraulic anchor. Background Art

[0002] Hydraulic anchor is a downhole tool commonly used to fix the pipe string in oilfield downhole fracturing, acidizing and other high-pressure operations. The hydraulic anchor is connected to the operating pipe string, and high-pressure liquid is injected into the oil pipe. The anchor claws set on the hydraulic anchor move outward under the action of pressure and anchor with the casing to fix the operating pipe string. Hydraulic anchor plays a key role in the processes of layered fracturing, layered acidizing, layered water injection, etc., and is related to the success of the construction.

[0003] In the prior art, hydraulic anchors are divided into two types. The first type is a hydraulic anchor without a filtering structure, in which the anchor claw structure is in direct contact with the liquid. The second type is a hydraulic anchor with an inner liner slotted pipe structure, in which the liquid is filtered through the slotted pipe and then contacts the anchor claw structure. The problem with both structures is that the liquid cannot avoid contacting the anchor claw structure, which may cause sand jamming and scale generation, causing the hydraulic anchor to fail. Summary of the invention

[0004] The purpose of the present invention is to solve the problems raised in the above background technology, and then proposes an anti-stuck double hydraulic water anchor.

[0005] The technical solution adopted by the present invention to solve the technical problem is: The cam is provided with a plurality of second hydraulic channels, the second hydraulic channels having a liquid inlet end and a liquid outlet end, and a group of anchor claw holes are provided above each group of second hydraulic channels, and a group of anchor claw structures are installed at each group of anchor claw holes; wherein the anchor claw structure comprises an anchor claw part, the anchor claw part is arranged in the anchor claw hole, a shell sleeve is provided on the inner side of the anchor claw part, and a shell sleeve sealing cover is provided on the inner side of the anchor claw hole to separate the anchor claw hole from the liquid; and a pressure-bearing part connected with the anchor claw part is provided on the shell sleeve, so that the pressure-bearing part pushes the anchor claw part to move outward after being subjected to liquid pressure; and a sealing part connected with the liquid outlet end of the second hydraulic channel is installed at the junction of the shell sleeve and the anchor body, so that after the second hydraulic channel enters the liquid, the sealing part expands and seals the junction between the shell sleeve and the anchor body to prevent liquid from seeping into the junction between the shell sleeve and the anchor body.

[0006] In the above solution, the anchor claw hole includes an inner hole, which is arranged inside the anchor body and is connected to a middle hole and an outer hole in sequence from inside to outside; wherein the middle hole is smaller than the inner hole and the outer hole, so that the anchor claw hole forms an I-shaped structure.

[0007] The above scheme further comprises that the anchor claw portion includes a piston, the piston is arranged in the inner hole, and a plurality of groups of first springs are arranged circumferentially between the piston and the outer wall of the inner hole, and a push rod is connected to the outer side of the piston, the push rod passes through the middle hole and is connected to the claw head arranged in the outer hole, so that the piston moves outward after being compressed.

[0008] Furthermore, the above scheme further comprises a sealing sleeve, which is arranged in the middle hole and connected to the push rod. The inner diameter of the sealing sleeve matches the outer diameter of the push rod, so that the sealing sleeve fits tightly to the outer wall of the push rod, thereby preventing the liquid on the outside of the claw head from leaking through the gap between the push rod and the middle hole.

[0009] The above scheme further comprises that the pressure-bearing part comprises a guide sleeve, which is horizontally fixed on the shell sleeve, and a pressure rod is slidably arranged in the guide sleeve, one end of the pressure rod extends out of the guide sleeve and is connected to a pressure plate, a telescopic sleeve is arranged between the pressure plate and the shell sleeve to cover the guide sleeve and the pressure rod and separate the guide sleeve and the pressure rod from the liquid, and the other end of the pressure rod extends out of the guide sleeve and is connected to a pressure seat connected to the piston.

[0010] Furthermore, in the above solution, the guide sleeve is welded to the shell sleeve or the two are integrally formed to improve the sealing performance of the two.

[0011] Furthermore, in the above solution, the pressure-bearing part also includes a second spring, which is arranged between the pressure-bearing plate and the shell and is located inside the telescopic sleeve.

[0012] Furthermore, the above scheme further comprises a tension membrane, which is fixedly covered on the inner side of the anchor claw hole and is located between the pressure seat and the piston to prevent liquid from leaking from the gap between the pressure seat and the piston into the anchor claw hole. At the same time, the tension membrane can adapt to the change of the relative position between the pressure seat and the piston, and always maintain the sealing effect on the gap during the pressure transmission process.

[0013] The above scheme further comprises a sealing part including a docking cover, a docking cover sealing cover is arranged at the liquid outlet end of the second hydraulic channel, and the docking cover is connected to a drainage tube, a top end of the drainage tube is connected to a liquid bag, and the liquid bag is arranged at the junction of the shell and the anchor body and wraps the shell.

[0014] Furthermore, the above scheme is that an air flow channel is provided on the anchor body, which connects each inner hole, and the end of the air flow channel extends to the outside of the upper connector and is connected to a ventilation pipe, and a valve is installed on the ventilation pipe. When the gas is injected into the inner hole through the ventilation pipe and the air flow channel, an elastic pressure chamber is formed inside the inner hole.

[0015] Furthermore, in the above solution, the second hydraulic channel is composed of a plurality of slits to achieve filtering of the liquid.

[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention divides the liquid into two passages through the design of the first hydraulic channel and the second hydraulic channel, and combined with the use of the anchor claw structure, it is possible to prevent liquid from entering the anchor claw hole; the liquid entering the first hydraulic channel cannot enter the anchor claw hole due to the obstruction of the shell, so that the anchor claw hole is separated from the liquid, which plays a role in protecting the anchor claw part, preventing it from directly contacting the liquid and causing sand jam and scale problems, thereby improving the reliability and service life of the hydraulic anchor and reducing the risk of failure caused by sand jam and scale; after the second hydraulic channel enters the liquid, the sealing part expands to seal the junction between the shell and the anchor body, further preventing the liquid from penetrating from the junction, ensuring the isolation effect of the anchor claw part and the liquid, and ensuring that the hydraulic anchor can work stably in a high-pressure and complex underground environment.

[0017] 2. The present invention can form an elastic pressure chamber through the coordinated arrangement of the air flow channel, the vent pipe and the valve. This design provides a reliable backup power source for the extension and retraction action of the claw head, effectively compensates for the possible problems of the first spring, improves the stability and reliability of the entire device, ensures that the claw head can perform normal extension and retraction action in a complex working environment, ensures the normal operation of the equipment, and has an ingenious and novel structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the overall structure of the present invention; Figure 2 for Figure 1 A is a partial enlarged schematic diagram; Figure 3 The figure is a schematic diagram of the installation position of the ventilation pipe; Figure 4 for Figure 3 A partial enlarged schematic diagram of B in the middle; Wherein: 1. anchor body; 11. first hydraulic channel; 12. second hydraulic channel; 13. anchor claw hole; 131. inner hole; 132. middle hole; 133. outer hole; 14. air flow channel; 2. upper connector; 3. lower connector; 4. anchor claw structure; 41. anchor claw part; 411. piston; 412. first spring; 413. push rod; 414. claw head; 415. sealing sleeve; 42. shell; 43. pressure part; 431. guide sleeve; 432. pressure rod; 433. pressure plate; 434. telescopic sleeve; 435. pressure seat; 436. second spring; 437. tension membrane; 44. sealing part; 441. docking cover; 442. drainage tube; 443. liquid bag; 5. ventilation pipe; 51. valve. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. The present invention is further described in combination with the drawings and embodiments: A double hydraulic anchor with anti-stuck structure, see attached Figure 1 As shown, it includes an anchor body 1, with an upper connector 2 and a lower connector 3 connected at both ends of the anchor body 1, a first hydraulic channel 11 is formed in the middle of the anchor body 1, and multiple groups of second hydraulic channels 12 are formed on the side of the anchor body 1. The second hydraulic channels 12 are composed of multiple slits to filter the liquid. The second hydraulic channels 12 have a liquid inlet end and a liquid outlet end, and each group of second hydraulic channels 12 is provided with a group of anchor claw holes 13 above each group of second hydraulic channels 12, and each group of anchor claw holes 13 is provided with a group of anchor claw structures 4; wherein the anchor claw structure 4 includes an anchor claw portion 41, and the anchor claw portion 41 is arranged in the anchor claw hole 13, A shell 42 is provided on the inner side of the anchor claw portion 41, and a sealing cover of the shell 42 is provided on the inner side of the anchor claw hole 13 to separate the anchor claw hole 13 from the liquid; and a pressure-bearing portion 43 connected to the anchor claw portion 41 is provided on the shell 42, so that the pressure-bearing portion 43 pushes the anchor claw portion 41 to move outward after being subjected to liquid pressure; and a sealing portion 44 connected to the liquid outlet end of the second hydraulic channel 12 is installed at the connection between the shell 42 and the anchor body 1, so that after the second hydraulic channel 12 enters the liquid, the sealing portion 44 expands and seals the connection between the shell 42 and the anchor body 1, so as to prevent liquid from seeping into the connection between the shell 42 and the anchor body 1.

[0020] In the specific implementation process of the present invention, the external hydraulic system transports liquid to the first hydraulic channel 11 in the middle of the anchor body 1 and the second hydraulic channel 12 on the side; the liquid entering the first hydraulic channel 11 cannot enter the anchor claw hole 13 due to the obstruction of the shell 42, so that the anchor claw hole 13 is separated from the liquid, which plays a role in protecting the anchor claw part 41 and preventing it from directly contacting the liquid and causing sand jam and scale problems; and the pressure-bearing part 43 arranged on the shell 42 is the part that directly contacts the liquid in the first hydraulic channel 11. When the pressure-bearing part 43 is pushed by the liquid pressure of the first hydraulic channel 11, it will prompt the anchor claw part 41 connected thereto to move outward, extend from the anchor claw hole 13, and then tightly grasp the well wall to achieve the anchoring function; when liquid enters the second hydraulic channel 12, the sealing part 44 will expand, thereby sealing the connection between the shell 42 and the anchor body 1, further preventing the liquid from penetrating from the connection, and ensuring the isolation effect of the anchor claw part 41 and the liquid.

[0021] For the above scheme, refer to the attached Figure 2As shown, the fluke hole 13 includes an inner hole 131, which is arranged on the inner side of the anchor body 1 and is connected with a middle hole 132 and an outer hole 133 in sequence from the inside to the outside, wherein the middle hole 132 is smaller than the inner hole 131 and the outer hole 133, so that the fluke hole 13 forms an I-shaped structure; in the scheme, the fluke hole 13 is designed to be an I-shaped structure, which includes the inner hole 131 with a larger size, the middle hole 132 with a smaller size, and the outer hole 133 with a larger size from the inside to the outside. This unique structure can position and guide the fluke portion 41. The size restriction of the middle hole 132 enables the fluke portion 41 to remain stable during movement without radial deviation or unanchoring, thereby ensuring that the fluke portion 41 can be accurately extended and retracted.

[0022] For the above scheme, refer to the attached Figure 2 As shown, the fluke portion 41 includes a piston 411, which is disposed in the inner hole 131, and a plurality of first springs 412 are disposed circumferentially between the piston 411 and the outer wall of the inner hole 131, and a push rod 413 is connected to the outer side of the piston 411, which passes through the middle hole 132 and is connected to a claw head 414 disposed in the outer hole 133, so that the piston 411 moves outward after being compressed; In the scheme, the piston 411 is located in the inner hole 131, and multiple groups of first springs 412 in the circumferential direction provide an inward restoring force for the piston 411. When the pressure-bearing portion 43 on the shell 42 is subjected to liquid pressure, the pressure is transmitted to the piston 411, overcoming the elastic force of the first spring 412, and pushing the piston 411 to move outward. The outward movement of the piston 411 drives the push rod 413 connected thereto. Since the push rod 413 passes through the middle hole 132 and is connected with the claw head 414 in the outer hole 133, the push rod 413 transmits the movement of the piston 411 to the claw head 414, so that the claw head 414 extends out of the outer hole 133 to achieve an anchoring action. When the liquid pressure disappears, the elastic force of the first spring 412 resets the piston 411 and retracts the claw head 414. The limiting design of the inner hole 131 for the piston 411 and the outer hole 133 for the claw head 414 effectively avoids the damage caused by excessive movement of the components. The outer hole 133 also constrains the movement of the claw head 414 with its own structure. The claw head 414 extends outward under the drive of the push rod 413. The outer hole 133 limits the excessive retraction of the claw head 414. When the claw head 414 is retracted inward to the limit position set by the outer hole 133 under the action of the first spring 412, the inner side of the claw head 414 abuts against the wall of the outer hole 133, avoiding the excessive retraction of the claw head 414 and failing to play the anchoring role normally, thereby ensuring that the claw head 414 can be in a position range where it can work normally under any working conditions. In addition, refer to the attached Figure 2 As shown, the anchor claw portion 41 also includes a sealing sleeve 415, which is disposed in the middle hole 132 and connected to the push rod 413. The inner diameter of the sealing sleeve 415 matches the outer diameter of the push rod 413, so that the sealing sleeve 415 fits tightly against the outer wall of the push rod 413, thereby preventing the liquid on the outer side of the claw head 414 from leaking through the gap between the push rod 413 and the middle hole 132.

[0023] In the above scheme, the pressure-bearing part 43 includes a guide sleeve 431, which is horizontally fixed on the shell sleeve 42. In order to improve the sealing performance of the two, the guide sleeve 431 and the shell sleeve 42 are welded and connected or the two are integrally formed, and a pressure rod 432 is slidably arranged in the guide sleeve 431, one end of the pressure rod 432 extends out of the guide sleeve 431 and is connected to a pressure plate 433, and a telescopic sleeve 434 is arranged between the pressure plate 433 and the shell sleeve 42 to cover the guide sleeve 431 and the pressure rod 432, so as to separate the guide sleeve 431 and the pressure rod 432 from the liquid, and the other end of the pressure rod 432 extends out of the guide sleeve 431 and is connected to a pressure seat 435 connected to the piston 411; In the scheme, when the liquid pressure acts on the pressure plate 433, the pressure plate 433 is forced to drive the pressure rod 432 to slide in the guide sleeve 431, and then the pressure is transmitted to the pressure seat 435 connected to the piston 411, and finally the piston 411 is pushed to move, so as to realize the extension of the anchor claw part 41. The telescopic sleeve 434 is arranged between the pressure plate 433 and the shell 42, and covers the guide sleeve 431 and the pressure rod 432. It can change accordingly with the extension and contraction of the pressure rod 432. While ensuring the normal movement of the pressure rod 432, the guide sleeve 431 and the pressure rod 432 are completely separated from the liquid to prevent the liquid from penetrating into the internal structure, thereby ensuring the normal working environment of the pressure transmission component. The pressure-bearing part 43 further includes a second spring 436, which is arranged between the pressure-bearing plate 433 and the shell 42 and inside the telescopic sleeve 434; when the pressure-bearing plate 433 is impacted by an external force, the second spring 436 can absorb and buffer part of the impact force, thereby reducing damage to the entire pressure-bearing part 43 and related components. By buffering the impact force and adjusting the pressure, the second spring 436 helps to reduce the pressure and stress borne by the sealing structure (such as the seal between the guide sleeve 431 and the shell 42, the seal of the telescopic sleeve 434, etc.), and reduces the risk of damage or leakage of the sealing part 44 due to excessive force, thereby further improving the sealing performance and overall reliability of the pressure-bearing part 43. After the external force disappears, the second spring 436 uses its elastic potential energy to push the pressure-bearing plate 433 to accurately reset, thereby ensuring the consistency and accuracy of each action of the device. In addition, from the perspective of sealing performance, refer to the attached Figure 2As shown, the pressure-bearing portion 43 further includes a tension membrane 437, which is fixedly covered on the inner side of the anchor claw hole 13 and is located between the pressure seat 435 and the piston 411. When the pressure seat 435 moves toward the piston 411 under the push of the pressure rod 432, the tension membrane 437 will be stretched by a certain tension. Since it is located between the pressure seat 435 and the piston 411, it can form a tight isolation layer to prevent liquid from leaking from the gap between the pressure seat 435 and the piston 411 to the anchor claw hole 13. At the same time, the tension membrane 437 can adapt to the change of the relative position between the pressure seat 435 and the piston 411, and always maintain the sealing effect on the gap during the pressure transmission process.

[0024] For the above scheme, refer to the attached Figure 2 As shown, the sealing part 44 includes a docking cover 441, which is arranged at the outlet end of the second hydraulic channel 12, and the docking cover 441 is connected to a drainage tube 442, and the top of the drainage tube 442 is connected to a liquid capsule 443, which is arranged at the junction of the shell 42 and the anchor body 1 and wraps the shell 42; In the scheme, when liquid flows out of the second hydraulic channel 12, the liquid enters the liquid capsule 443 through the docking cover 441 and the drainage tube 442, causing the liquid capsule 443 to expand. The expanded liquid capsule 443 will fit tightly at the junction of the shell sleeve 42 and the anchor body 1 to form a sealed space, preventing external liquid from entering the connection between the shell sleeve 42 and the anchor body 1, thereby playing a role of sealing and isolation. In addition, the liquid capsule 443 wraps the shell sleeve 42, which not only protects the shell sleeve 42 from being eroded by the external environment, but also further enhances the sealing of the entire sealing part 44. Even if there are tiny gaps or unevenness on the surface of the shell sleeve 42, the liquid capsule 443 can fill them through its own elastic deformation to ensure the sealing effect.

[0025] In the above solution, considering that the first spring 412 may have problems during long-term use, thereby affecting the telescopic action of the claw head 414, Figure 3 and attached Figure 4 As shown, the anchor body 1 is provided with an air flow channel 14, which connects each inner hole 131, and the end of the air flow channel 14 extends to the outside of the upper connector 2 and is connected to the vent pipe 5, and the vent pipe 5 is installed with a valve 51. When the gas is injected into the inner hole 131 through the vent pipe 5 and the air flow channel 14, an elastic pressure chamber is formed inside the inner hole 131 (the gas is compressible); In the scheme, when subjected to external force, the thrust of piston 411 is greater than the pressure in the pressure chamber. At this time, piston 411 moves outward to extend claw head 414. When the external force disappears, the previously compressed gas in the pressure chamber begins to expand. The gas expansion will generate an outward pressure, which acts on piston 411, pushing piston 411 to move to the initial position, thereby restoring piston 411 to its original position. During the telescopic action of claw head 414, when the first spring 412 has problems and cannot work normally, the pressure chamber can replace the first spring 412 to play a role. This elastic pressure chamber formed based on gas pressure provides a reliable backup power source for the telescopic action of claw head 414, effectively compensates for the problems that may occur in the first spring 412, improves the stability and reliability of the entire device, ensures that the claw head 414 can perform telescopic action normally in a complex working environment, and ensures the normal operation of the equipment.

[0026] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of the present invention is defined by the attached claims and their equivalents.

Claims

1. An anti-stuck double hydraulic anchor, comprising an anchor body (1), an upper connector (2) and a lower connector (3) being connected at both ends of the anchor body (1), and a first hydraulic channel (11) being formed in the middle of the anchor body (1), characterized in that: A plurality of groups of second hydraulic channels (12) are formed on the side of the anchor body (1), the second hydraulic channels (12) having a liquid inlet end and a liquid outlet end, and a group of anchor claw holes (13) are respectively provided above each group of second hydraulic channels (12), and a group of anchor claw structures (4) are respectively installed at the position of each group of anchor claw holes (13); The anchor claw structure (4) comprises an anchor claw portion (41), the anchor claw portion (41) being arranged in the anchor claw hole (13), a shell (42) being arranged inside the anchor claw portion (41), a sealing cover of the shell (42) being arranged inside the anchor claw hole (13) to separate the anchor claw hole (13) from liquid; a pressure-bearing portion (43) connected to the anchor claw portion (41) being arranged on the shell (42), so that the pressure-bearing portion (43) pushes the anchor claw portion (41) to move outward after receiving liquid pressure; and a sealing portion (44) connected to the liquid outlet end of the second hydraulic channel (12) being installed at the connection between the shell (42) and the anchor body (1), so that after the second hydraulic channel (12) enters the liquid, the sealing portion (44) expands and seals the connection between the shell (42) and the anchor body (1).

2. The anti-stuck double hydraulic anchor according to claim 1, characterized in that: The anchor claw hole (13) comprises an inner hole (131), which is arranged inside the anchor body (1) and is connected to a middle hole (132) and an outer hole (133) in sequence from inside to outside; The size of the middle hole (132) is smaller than the size of the inner hole (131) and the size of the outer hole (133), so that the anchor claw hole (13) forms an I-shaped structure.

3. The anti-stuck double hydraulic anchor according to claim 2, characterized in that: The anchor claw portion (41) comprises a piston (411), the piston (411) is arranged in the inner hole (131), and a plurality of groups of first springs (412) are arranged on the circumference between the piston (411) and the outer wall of the inner hole (131), and a push rod (413) is connected to the outer side of the piston (411), and the push rod (413) passes through the middle hole (132) and is connected to a claw head (414) arranged in the outer hole (133), so that the piston (411) moves outward after being compressed.

4. The anti-stuck double hydraulic anchor according to claim 3, characterized in that: The anchor claw portion (41) further comprises a sealing sleeve (415), which is arranged in the middle hole (132) and connected to the push rod (413). The inner diameter of the sealing sleeve (415) matches the outer diameter of the push rod (413), so that the sealing sleeve (415) fits tightly against the outer wall of the push rod (413).

5. The anti-stuck double hydraulic anchor according to claim 4, characterized in that: The pressure-bearing portion (43) comprises a guide sleeve (431), the guide sleeve (431) being fixedly arranged horizontally on the shell sleeve (42), and a pressure rod (432) being slidably arranged in the guide sleeve (431), one end of the pressure rod (432) extending out of the guide sleeve (431) and being connected to a pressure plate (433), a telescopic sleeve (434) being arranged between the pressure plate (433) and the shell sleeve (42) to cover the guide sleeve (431) and the pressure rod (432) and to separate the guide sleeve (431) and the pressure rod (432) from the liquid, and the other end of the pressure rod (432) extending out of the guide sleeve (431) and being connected to a pressure seat (435) connected to the piston (411).

6. The anti-stuck double hydraulic anchor according to claim 5, characterized in that: The pressure-bearing portion (43) further comprises a second spring (436), which is arranged between the pressure-bearing plate (433) and the shell (42) and is located inside the telescopic sleeve (434).

7. The anti-stuck double hydraulic anchor according to claim 6, characterized in that: The pressure-bearing portion (43) further comprises a tension membrane (437), which is fixedly covered on the inner side of the fluke hole (13) and is located between the pressure seat (435) and the piston (411).

8. The anti-stuck double hydraulic anchor according to claim 7, characterized in that: The sealing portion (44) comprises a docking cover (441), the docking cover (441) being a sealing cover arranged at the liquid outlet end of the second hydraulic channel (12), and the docking cover (441) being connected to a drainage tube (442), the top end of the drainage tube (442) being connected to a liquid capsule (443), and the liquid capsule (443) being arranged at the junction of the shell (42) and the anchor body (1) and wrapping the shell (42).

9. The anti-stuck double hydraulic anchor according to claim 8, characterized in that: The anchor body (1) is provided with an air flow channel (14), the air flow channel (14) connects each inner hole (131), and the end of the air flow channel (14) extends to the outside of the upper connector (2) and is connected to a vent pipe (5), and a valve (51) is installed on the vent pipe (5). When gas is injected into the inner hole (131) through the vent pipe (5) and the air flow channel (14), an elastic pressure chamber is formed inside the inner hole (131).

10. An anti-stuck double hydraulic anchor according to any one of claims 1 to 9, characterized in that: The second hydraulic channel (12) is composed of a plurality of slits.

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