CN220551078U

CN220551078U - Self-locking bidirectional hydraulic slip

Info

Publication number: CN220551078U
Application number: CN202322268285.4U
Authority: CN
Inventors: 张卫卫; 王莉; 李永康; 谭云贤; 孙冰洁; 肖喜龙
Original assignee: China Petroleum and Chemical Corp; Sinopec Shengli Oilfield Co
Current assignee: China Petroleum and Chemical Corp; Sinopec Shengli Oilfield Co
Priority date: 2023-08-23
Filing date: 2023-08-23
Publication date: 2024-03-01
Anticipated expiration: 2033-08-23

Abstract

The utility model discloses a self-locking bidirectional hydraulic slip, which comprises a central pipe, wherein an anchoring mechanism, a self-locking mechanism and a jam releasing mechanism are sleeved outside the central pipe; the anchoring mechanism is provided with slip teeth which are divided into an upper slip tooth and a lower slip tooth, and the directions of the upper slip tooth and the lower slip tooth are opposite. The slip teeth adopt a bidirectional design, so that the pipe column is prevented from creeping downwards and upwards, the pipe column is anchored more reliably, the rubber cylinder in the anchoring mechanism is attached to the elastic steel sheet, the stress area and the stress balance degree of the elastic steel sheet are increased in the pressing and expanding sealing process, and the anchoring effect is ensured; meanwhile, due to the elastic material of the rubber cylinder, the impact of hydraulic pressure on the slip teeth is buffered, and the damage of the slip teeth to the inner wall of the sleeve is reduced.

Description

Self-locking bidirectional hydraulic slip

Technical Field

The utility model relates to the technical field of petroleum exploitation tools, in particular to a self-locking bidirectional hydraulic slip.

Background

In the development process of the oil field, the separate layer water injection is an important means for solving the interlayer contradiction, maintaining the stratum energy and maintaining the long-term stable and high yield of the oil field, and is also the most economical development means at present. The working state of the water injection well pipe column in the pit generally comprises water injection, stop injection, back flushing, high-pressure acidification and the like, and when different working conditions are switched, a certain creep amount exists in the well pipe column, and the creep is fatal to the packer rubber. In order to prevent the peristaltic movement of the pipe column, the current common technical measure is that the upper end of the pipe column is connected with a hydraulic anchor, the lower end of the pipe column is connected with a hydraulic slip, the hydraulic anchor plays a role in anchoring the pipe column, and the hydraulic slip plays a role in supporting and anchoring. The working principles of the hydraulic anchor and the hydraulic slip are as follows: when the interior of the pipe column is pressed, the fluke and the slip teeth extend out and are clamped on the inner wall of the sleeve, so that the water injection pipe column is anchored; however, when the injection is stopped or the well is backwashed so that the pressure of the oil jacket is balanced, the flukes and the slip teeth can be recovered, and the anchoring is released.

Publication (bulletin) number: CN219299254U discloses a hydraulic anchor, comprising an anchor body (1), flukes (7), a pressing plate (8) and a floating base (6), wherein the middle part of the floating base (6) is provided with flukes mounting grooves extending towards the central axis along the radial direction, and a first spring (5) for applying elastic supporting force to the floating base (6) along the radial direction is arranged between the anchor body (1) and the floating base (6); the pressing plate (8) is fixed on the floating base (6), and a second spring (10) for driving the fluke (7) and the pressing plate (8) to be separated from each other in the radial direction is propped between the fluke (7) and the pressing plate (8); the external diameter of the hydraulic anchor that this prior art provided can shrink certain size to increased the external diameter of hydraulic anchor and when getting into tubular column and through the sleeve pipe reducing section applicable scope, owing to used the two-stage spring and can increase the radial displacement of fluke, avoided the problem that the resilience performance that leads to for increasing fluke spring force is low, and can reduce the risk of card well.

This prior art has the great problem of injury to the sleeve pipe, still has the problem that can't lock.

Publication (bulletin) number: CN110630197B discloses a hydraulic anchor, which comprises a central tube, a moving assembly sleeved on the central tube, and an anchoring assembly, wherein the anchoring assembly realizes the clamping and releasing of a pipe column through the linear movement of the moving assembly in the central tube; the moving assembly comprises a piston, a cylinder sleeve and a movable cone which are sequentially sleeved on the central tube; the anchor assembly is arranged in the cavity between the upper joint and the movable cone, the anchor assembly comprises a glass fiber slip, a clamp spring and a ring sleeve, the two sides of the end face, close to the central tube, of the glass fiber slip are matched with the movable cone and the conical surface of the upper joint, the end face, close to the clamp spring, of the glass fiber slip is provided with an inwards concave arc surface, the clamp spring is of an arc-shaped structure with an opening facing the glass fiber slip, and the arc surface of the glass fiber slip is provided with a plurality of stress release grooves. This prior art has the advantage that improves structural strength, avoids the internal structure fracture to cause sitting card and the unfreezing of whole structure.

This prior art can lock but has the problem that it cannot be anchored in both directions.

Publication (bulletin) number: CN218934377U discloses a compression type bi-directional anchoring bridge plug. Relates to the technical field of oilfield downhole tools. The upper side of the central tube is connected with a push ring through a setting pin, the push ring extends downwards for a section of push tube, an upper slip, an upper cone, a rubber cylinder, a lower cone and a lower slip are sequentially connected onto the push tube from top to bottom, a lever is arranged at the lower part of the lower slip and is connected with a guide base through a shaft, the outer side of the lever is propped against the bottom of the lower slip, and the inner side of the lever is propped against the bottom of the push tube. The prior art has the following beneficial effects: the setting tool is used for pushing the push ring, the setting pin is sheared, the push ring descends to push the upper slips to move downwards to be opened, meanwhile, the push pipe pushes the lower slips to move upwards to be opened through the lever, after the upper slips and the lower slips are opened, the bridge plug is anchored in the sleeve in a bidirectional manner, the push ring is continuously pushed, the upper shear pin and the lower shear pin are sheared, the rubber cylinder is compressed at the same time, and the rubber cylinder does not move axially in the expansion process, so that the sealing effect is good.

The prior art realizes bidirectional anchoring and locking, but the problem that unidirectional teeth are broken and the locking is invalid exists when unidirectional teeth are used for locking, and the problem that the unidirectional teeth are ground flat can occur when the unidirectional teeth are used for multiple times.

In summary, the technical scheme of the above disclosed technology, the technical problems to be solved and the beneficial effects are different from those of the present utility model, and the above disclosed technical documents have no technical teaching for more technical features of the present utility model, the technical problems to be solved and the beneficial effects.

Disclosure of Invention

Aiming at the defects existing in the prior art, the utility model aims to provide a self-locking bidirectional hydraulic slip, solve the problem of upward and downward peristaltic movement of a pipe column, realize bipolar self-locking, ensure the self-locking effect to realize long-term effective supporting and anchoring, reduce the impact of hydraulic pressure on slip teeth directly and reduce the damage of the slip teeth on the inner wall of a sleeve.

In order to achieve the above purpose, the present utility model adopts the following technical scheme:

the self-locking bidirectional hydraulic slip comprises a central pipe, wherein an anchoring mechanism, a self-locking mechanism and a jam releasing mechanism are sleeved outside the central pipe; the anchoring mechanism is provided with slip teeth which are divided into an upper slip tooth and a lower slip tooth, and the directions of the upper slip tooth and the lower slip tooth are opposite.

The anchoring mechanism is connected with the self-locking mechanism through a lock sleeve; the anchoring mechanism is connected with the lower end of the lock sleeve; the self-locking mechanism is connected with the upper end of the lock sleeve.

The anchoring mechanism comprises a sealing ring, a baffle ring, a rubber cylinder, an elastic steel sheet, slip teeth, a tooth socket and a lower baffle cap.

The central tube is sleeved with a sealing ring and a rubber cylinder, the rubber cylinder is arranged below the sealing ring, the baffle ring is in threaded connection with the upper end of the rubber cylinder, and the lower baffle cap is arranged at the lower end of the rubber cylinder;

the retainer ring and the lower retainer cap form a clamping groove, and the tooth socket is arranged in the clamping groove;

at least two through grooves are formed in the tooth socket, and the slip teeth are arranged in the through grooves;

the upper end and the lower end of the slip teeth are covered by the tooth sleeves; an elastic steel sheet is arranged between the slip teeth and the rubber cylinder.

The sealing ring is provided with a pressure transmission channel, the central tube is provided with a pressure transmission hole above the sealing ring, and the central tube is provided with a thin-wall area;

the lower end of the thin-wall area is higher than the lower end of the rubber cylinder, the upper end of the thin-wall area is arranged between the upper end of the rubber cylinder and the upper end of the sealing ring, and the thin-wall area, the rubber cylinder and the sealing ring form a pressure cavity.

The upper slip segments are oriented toward an axially upper end and the lower slip segments are oriented toward an axially lower end.

The self-locking mechanism comprises an upper joint, a blocking sleeve, a self-locking shear pin, a locking ring, a clamping ring seat and a one-way valve.

The upper joint is in threaded connection with the upper end of the central tube;

the clamping ring seat is sleeved outside the central tube, the upper end of the clamping ring seat is connected with the upper joint through a self-locking shear pin, and the lower end of the clamping ring seat is connected with the lock sleeve through a clamping ring;

the snap ring is placed in the snap ring space of the snap ring seat, the outer wall of the snap ring is provided with an upward inclined plane, a part of the snap ring, which normally stretches out of the snap ring seat, is matched with a limit groove on the lock sleeve to prevent the snap ring seat from falling, and the snap ring is retracted into the snap ring space of the snap ring seat when the snap ring seat rises.

The lower end of the snap ring seat is provided with an ejector rod;

the check valve is arranged on the pressure transmission channel of the sealing ring and comprises a valve ball seat, a valve ball and a spring, and the spring pushes the valve ball in the valve ball seat under the condition of no external force; and in the initial state, the ejector rod pushes a valve ball in the one-way valve open so as to conduct the pressure transmission channel.

The retaining sleeve is sleeved outside the upper joint, the outer wall of the lower end of the retaining sleeve is in threaded connection with the lock sleeve, and the inner wall of the retaining sleeve is sealed with the clamping ring seat; a locking block is further arranged between the lower end of the blocking sleeve and the lower end of the upper joint, and a second pressure transmission channel is arranged at the lower end of the blocking sleeve to guide hydraulic pressure to the locking block;

the snap ring seat is provided with the locked groove below the locking piece, the locked groove corresponds to the locking piece, and when the locking piece is seated in the locked groove, the snap ring seat is locked.

The unclamping mechanism comprises an unclamping shear pin, a central tube, a small spring and a lower connector.

The blocking sleeve is connected with the upper joint through the unclamping shear pin; the lower end of the central tube is placed in the groove of the lower joint;

the lower connector is in threaded connection with the lower retaining cap, and the lower connector and the central tube seal the lower end of the rubber cylinder; a clamping step is arranged between the upper connector and the retaining sleeve, the clamping step is not contacted in the initial state, and when the upper connector moves upwards, the clamping step is clamped when the unlocking is completed;

the small spring is arranged between the elastic steel sheet and the tooth socket.

Compared with the prior art, the utility model has the following beneficial effects:

1. the slip teeth adopt a bidirectional design, so that the pipe column is prevented from creeping downwards and upwards, and the pipe column is anchored more reliably.

2. The rubber cylinder is attached to the elastic steel sheet, so that the stress area and the stress balance degree of the elastic steel sheet are increased in the pressing and expanding sealing process, and the anchoring effect is ensured; meanwhile, due to the elastic material of the rubber cylinder, the impact of hydraulic pressure on the slip teeth is buffered, and the damage of the slip teeth to the inner wall of the sleeve is reduced.

3. Realizing double-stage self-locking and ensuring self-locking effect.

4. The card releasing device has the function of forced card releasing, and ensures the reliability of card releasing.

Drawings

FIG. 1 is a schematic diagram of a self-locking bi-directional hydraulic slip of the present utility model;

FIG. 2 is a schematic view of a partially enlarged construction of the self-locking bi-directional hydraulic slip of the present utility model;

in the figure: 1. an upper joint; 2. unclamping shear pins; 3. a blocking sleeve; 4. self-locking shear pins; 5. a locking piece; 6. a lock sleeve; 7. a clasp; 8. a first sealing rubber ring; 9. a clasp mount; 10. a valve ball seat; 11. a valve ball; 12. a spring; 13. a seal ring; 14. the second sealing rubber ring; 15. a baffle ring; 16. a central tube; 17. a rubber cylinder; 18. an elastic steel sheet; 19. slip teeth; 20. a tooth socket; 21. a small spring; 22. a lower retaining cap; 23. and a lower joint.

Detailed Description

The following description of the embodiments of the present utility model will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present utility model, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

Referring to fig. 1 and 2, the self-locking bidirectional hydraulic slip provided by the utility model comprises a central tube 16, wherein an anchoring mechanism, a self-locking mechanism and a releasing mechanism are sleeved outside the central tube 16;

the anchoring mechanism is connected with the self-locking mechanism through a lock sleeve 6;

the anchoring mechanism comprises a sealing ring 13, a baffle ring 15, a rubber cylinder 17, an elastic steel sheet 18, slip teeth 19, a tooth socket 20 and a lower baffle cap 22;

the center tube 16 is sleeved with a sealing ring 13 and a rubber cylinder 17, the rubber cylinder 17 is arranged below the sealing ring 13, the baffle ring 15 is in threaded connection with the upper end of the rubber cylinder 17, and the lower baffle cap 22 is arranged at the lower end of the rubber cylinder 17;

the retaining ring 15 and the lower retaining cap 22 form a clamping groove, the tooth socket 20 is arranged in the clamping groove, at least two through grooves are formed in the tooth socket 20, the slip teeth 19 are arranged in the through grooves, and the upper end and the lower end of the slip teeth 19 are covered by the tooth socket 20 to limit movement; an elastic steel sheet 18 is arranged between the slip teeth 19 and the rubber cylinder 17;

the sealing ring 13 is provided with a pressure transmission channel, the outer wall of the sealing ring 13 is sealed with the lock sleeve 6, the inner wall is sealed with the central tube 16, the central tube 16 is provided with a pressure transmission hole above the sealing ring 13, the central tube 16 is provided with a thin-wall area, the lower end of the thin-wall area is higher than the lower end of the rubber drum 17, the upper end of the thin-wall area is higher than the upper end of the rubber drum 17 and lower than the upper end of the sealing ring 13, the thin-wall area, the rubber drum 17 and the sealing ring 13 form a pressure cavity, when the pressure in the central tube 16 rises, the pressure in the central tube 16 enters the cavity above the sealing ring 13 from the pressure transmission hole, passes through the pressure transmission channel, and enters the pressure cavity between the sealing ring 13 and the baffle ring 15, so that the rubber drum 17 expands, the elastic steel sheet 18 is jacked up, and the slip teeth 19 extend to be anchored.

The slip teeth 19 adopt opposite bidirectional designs, and the upper slip teeth on the upper part face the upper end in the axial direction, so as to support the pipe column and prevent the pipe column from creeping downwards; the lower slip teeth of the lower part face the lower end of the axial direction, so that the pipe column is prevented from creeping upwards, and the pipe column is anchored more reliably due to the bidirectional design.

The self-locking mechanism is connected with the upper end of the lock sleeve;

the self-locking mechanism includes: the self-locking shear pin comprises an upper joint 1, a baffle sleeve 3, a self-locking shear pin 4, a locking ring 5, a clamping ring 7, a clamping ring seat 9 and a one-way valve;

the upper joint 1 is in threaded connection with the upper end of the central tube 16; the clamping ring seat 9 is sleeved on the central tube, the upper end of the clamping ring seat is connected with the upper joint 1 through the self-locking shear pin 4, and the lower end of the clamping ring seat is connected with the lock sleeve 6 through the clamping ring 7; the clamping ring 7 is placed in a clamping ring space of the clamping ring seat 9, an upward inclined surface is arranged on the outer wall of the clamping ring 7, a part of the clamping ring 7 which normally extends out of the clamping ring seat 9 is matched with a limit groove on the lock sleeve 6 to prevent the clamping ring seat 9 from falling, and when the clamping ring seat 9 rises, the clamping ring is retracted into the clamping ring space of the clamping ring seat 9;

the lower end of the snap ring seat 9 is provided with a push rod, the one-way valve is arranged on a pressure transmission channel of the sealing ring 13, and the push rod pushes up a valve ball 11 in the one-way valve to enable the pressure transmission channel to be communicated in an initial state; the check valve comprises a valve ball seat 10, a valve ball 11 and a spring 12, wherein the spring 12 pushes the valve ball 11 in the valve ball seat 10 under the condition of no external force;

the retaining sleeve 3 is sleeved outside the upper joint 1, the outer wall of the lower end is in threaded connection with the lock sleeve 6, and the inner wall is sealed with the clamping ring seat; a locking block 5 is further arranged between the lower end of the baffle sleeve 3 and the lower end of the upper joint 1, and a second pressure transmission channel is arranged at the lower end of the baffle sleeve 3 to guide hydraulic pressure to the locking block 5;

the snap ring seat 9 is provided with the locking groove below the locking piece 5, the central pipe 16 is pressurized, when the anchoring mechanism finishes anchoring, the self-locking shear pin 4 is sheared, the snap ring seat 9 is pushed to move upwards, the ejector rod breaks away from the one-way valve, the one-way valve is closed, the anchoring mechanism finishes locking, the locking groove corresponds to the locking piece 5, and the locking piece 5 sits in the locking groove under the pressure of the second pressure transmission channel to lock the snap ring seat 9.

The unclamping mechanism comprises: the unclamping shear pin 2, the central tube 16, the small spring 21 and the lower joint 23;

the unclamping shear pin 2 is arranged between the retaining sleeve 3 and the upper joint 1; the lower end of the central tube 16 is placed in a groove of the lower joint 23; the lower joint 23 is in threaded connection with the lower baffle cap 22, and a sealing rubber ring is arranged between the central tube 16 and the lower joint 23 to seal the rubber cylinder 17; the small spring 21 is arranged between the elastic steel sheet 18 and the tooth socket 20;

the upper joint 1 and the retaining sleeve 3 are provided with clamping steps, the clamping steps are not contacted in the initial state, and when the upper joint 1 moves upwards, the clamping steps are clamped when the clamping release is completed.

When the pipe column is released, the pipe column is lifted up, the releasing shear pin 2 is cut off, the central pipe 16 moves upwards, the lower end of the central pipe leaves the groove of the lower joint 23, the sealing of the rubber cylinder 17 is released, the pressure in the pressure cavity is released from the gap between the central pipe 16 and the lower joint 23, the elastic steel sheet 18 automatically returns, and when the automatic return fails, the small spring 21 returns the elastic steel sheet 18, and the anchoring is released.

The using method comprises the following steps:

s1, descending a well: according to the construction design, connecting oil pipes or other downhole tools at the upper end and the lower end of the self-locking bidirectional hydraulic slips, and descending to the design depth.

S2, anchoring: the hydraulic pressure is pumped into the pipe column, the liquid enters a cavity between the clamping ring seat 9 and the sealing ring 13 through a pressure transmission hole on the central pipe 16, and reaches a pressure cavity between the central pipe 16 and the rubber cylinder 17 through a one-way valve and a pressure transmission channel which are jacked up by the ejector rod; the rubber cylinder 17 is pushed by hydraulic pressure to expand and seal, so that the elastic steel sheet 18 is pushed to expand outwards, the elastic steel sheet 18 pushes the slip teeth 19 to extend out to clamp the inner wall of the sleeve, and the hydraulic slip support anchoring function is achieved.

When the hydraulic pressure in the tubular column continuously increases, the hydraulic pressure promotes snap ring seat 9 to move upwards to shear self-locking shear pin 4, after snap ring seat 9 moves upwards, valve ball 11 moves upwards to sit on valve ball seat 10 under the elasticity of spring 12, the inside hydraulic pressure of anchoring mechanism can tightly compress valve ball 11 on valve ball seat 10, realize airtight state, guarantee that the hydraulic pressure in center tube 16 and the packing element 17 can not be released, if there is not pressure in the tubular column at this moment, the slips tooth also can keep stretching out the state all the time, reach the effect of auto-lock, realize long-term effectual support anchoring.

S3, unlocking: when the pipe column is inspected and replaced in the later period, the pipe column is required to be lifted, the upper joint 1 shears off the unclamping shear pin 2, at the moment, the upper joint 1 drives the central pipe 16 to move upwards, after the sealing rubber ring at the lower end of the central pipe moves out of the sealing surfaces of the central pipe 16 and the lower joint 23, hydraulic pressure in the pressure cavity between the central pipe 16 and the rubber tube 17 is discharged through a gap between the central pipe and the lower joint, the rubber tube 17 and the elastic steel sheet 18 are gradually retracted to an initial state, the slip teeth 19 are also naturally retracted to the initial state, and support and anchoring are released;

when the phenomenon that the rubber cylinder 17 or the elastic steel sheet 18 is not easy to recover or the slip teeth 19 and the inner wall of the sleeve form scale is generated, the small springs 21 can forcedly push the elastic steel sheet 18 and the slip teeth 19 to retract, so that the forced unlocking effect is realized, and the unlocking reliability is ensured.

All parts themselves which are not discussed in the present application and all parts connection modes in the present application belong to the known technology in the technical field. The preparation can be directly applied and is not repeated.

In the present utility model, the term "plurality" means two or more, unless explicitly defined otherwise. The terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; "coupled" may be directly coupled or indirectly coupled through intermediaries. The specific meaning of the above terms in the present utility model can be understood by those of ordinary skill in the art according to the specific circumstances.

In the description of the present utility model, it should be understood that the directions or positional relationships indicated by the terms "upper", "lower", "left", "right", "front", "rear", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of describing the present utility model and simplifying the description, and do not indicate or imply that the devices or units referred to must have a specific direction, be constructed and operated in a specific direction, and thus should not be construed as limiting the present utility model.

In the description of the present specification, the terms "one embodiment," "some embodiments," "particular embodiments," and the like, mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present utility model. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The above description is only of the preferred embodiments of the present utility model and is not intended to limit the present utility model, but various modifications and variations can be made to the present utility model by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present utility model should be included in the protection scope of the present utility model.

Claims

1. The self-locking bidirectional hydraulic slip comprises a central pipe and is characterized in that an anchoring mechanism, a self-locking mechanism and a jam releasing mechanism are sleeved outside the central pipe;

the anchoring mechanism is provided with slip teeth which are divided into an upper slip tooth and a lower slip tooth, and the directions of the upper slip tooth and the lower slip tooth are opposite.

2. The self-locking two-way hydraulic slip of claim 1, wherein the anchoring mechanism is anchored using a hydraulic expansion seal of a packing element.

3. The self-locking two-way hydraulic slip of claim 2, wherein the anchoring mechanism is connected with the self-locking mechanism through a locking sleeve; the anchoring mechanism is connected with the lower end of the lock sleeve; the self-locking mechanism is connected with the upper end of the lock sleeve.

4. The self-locking bi-directional hydraulic slip of claim 3 wherein the anchoring mechanism comprises a sealing ring, a retainer ring, a packing element, a spring steel sheet, slip teeth, a tooth socket, a lower retaining cap;

the central tube is sleeved with a sealing ring and a rubber cylinder, the rubber cylinder is arranged below the sealing ring, the baffle ring is connected with the upper end of the rubber cylinder, and the lower baffle cap is arranged at the lower end of the rubber cylinder;

5. The self-locking bidirectional hydraulic slip according to claim 4, wherein a pressure transmission channel is arranged on the sealing ring, a pressure transmission hole is arranged above the sealing ring on the central tube, and a thin-wall area is arranged on the central tube;

6. The self-locking bi-directional hydraulic slip of claim 5, wherein the upper slip bowl is oriented toward an axially upper end and the lower slip bowl is oriented toward an axially lower end.

7. The self-locking bi-directional hydraulic slip of claim 6, wherein the self-locking mechanism comprises an upper joint, a stop collar, a self-locking shear pin, a locking ring, a snap ring seat, a one-way valve;

8. The self-locking two-way hydraulic slip according to claim 7, wherein the lower end of the clasp seat is provided with a push rod;

9. The self-locking bidirectional hydraulic slip according to claim 8, wherein the retaining sleeve is sleeved outside the upper joint, the outer wall of the lower end is in threaded connection with the locking sleeve, and the inner wall is sealed with the clamping ring seat; a locking block is further arranged between the lower end of the blocking sleeve and the lower end of the upper joint, and a second pressure transmission channel is arranged at the lower end of the blocking sleeve to guide hydraulic pressure to the locking block;

10. The self-locking bi-directional hydraulic slip of claim 9, wherein the unclamping mechanism comprises an unclamping shear pin, a center tube, a small spring, a lower joint;