CN112282689B - Soluble packer and using method thereof - Google Patents

Abstract

The invention provides a soluble packer and a using method thereof, and the soluble packer comprises an upper joint and a central tube, wherein the lower end of the upper joint is connected with the outer wall of the central tube, an adjusting ring is arranged outside the upper joint, a sealing mechanism and a top ring are sequentially sleeved outside the central tube from top to bottom, a cone is arranged in the middle of the sealing mechanism, an annular hoop is arranged on the sealing mechanism, a push cylinder is connected below the top ring, a hydraulic mechanism is connected below the push cylinder, a liquid inlet hole communicated with the hydraulic mechanism is arranged on the central tube, and the lower end of the hydraulic mechanism is fixedly connected with a hydraulic cover through a setting shear pin; the center tube is fixed with the deblocking cover through the deblocking shear pin, and the deblocking cover outside is equipped with the locking and detains, and the pushing cylinder lower part is equipped with the hasp, and the left lower part of locking detaining is located to the hasp, and locking detains and hasp phase-match, and sealing mechanism and cone all adopt magnesium aluminum alloy soluble material. The soluble packer can be provided with a plurality of hydraulic cylinders according to setting force, a sealing mechanism is formed by adopting mechanism movement, the setting force is small, the control is accurate, and the deblocking process is smooth.

Description

Soluble packer and using method thereof

Technical Field

The invention belongs to the technical field of oil and gas field development, and particularly relates to a soluble packer and a using method thereof.

Background

The packer mainly realizes the packing of a production zone or a construction target zone, prevents fluid and pressure between layers from interfering with each other, adapts to the construction requirements of various layering technologies, has a use range almost covering all production links of exploration and development, and particularly in the field of oil and gas field transformation, and the segmented transformation of the packer is one of important technologies for realizing the effective utilization of multiple layers and multiple sections of low-permeability and compact oil and gas reservoirs. After the packer finishes the packing function, a shaft needs to be pulled out, the problem that the packer is difficult to unseal is caused due to the existence of various reasons such as underground corrosion scaling and sand setting, and the tubular column cannot be pulled out, so that the production of an oil-gas well and the overhaul and replacement in the later period are influenced.

Disclosure of Invention

The object of the present invention is to provide a soluble packer overcoming the above mentioned technical problems existing in the prior art.

The invention aims to provide a using method of a soluble packer, which ensures that the packer can be smoothly lifted out of a shaft.

Therefore, the technical scheme provided by the invention is as follows:

a soluble packer comprises an upper joint and a central pipe, wherein the lower end of the upper joint is connected with the outer wall of the central pipe, an adjusting ring is arranged outside the upper joint, a sealing mechanism and a top ring are sequentially sleeved outside the central pipe from top to bottom, a cone is arranged in the middle of the sealing mechanism, an annular hoop is arranged on the sealing mechanism, a push cylinder is connected below the top ring, a hydraulic mechanism is connected below the push cylinder, a liquid inlet hole communicated with the hydraulic mechanism is formed in the central pipe, and the lower end of the hydraulic mechanism is fixedly connected with a hydraulic cover through a setting shear pin;

the center tube is fixed with through the deblocking shear pin and separates the cover, the deblocking cover outside is equipped with the locking and detains, the pusher lower part is equipped with the hasp, the left lower part of locking knot is located to the hasp, locking knot and hasp phase-match, sealing mechanism and cone all adopt magnesium aluminum alloy soluble material.

The hydraulic mechanism is a hydraulic cylinder or a plurality of hydraulic cylinders which are sequentially connected from top to bottom, each hydraulic cylinder comprises a cylinder body and a piston in the cylinder body, and the cylinder body is fixedly connected with the hydraulic cover through a setting shear pin.

Sealing mechanism includes upper seal group and lower seal group, upper seal group includes a plurality of upper seal blocks, lower seal group includes a plurality of lower seal blocks, upper seal group seat, upper seal block, lower seal block and lower seal group seat set gradually from last to lower.

The center tube includes center tube and lower center tube, the top of center tube meets with the bottom of apical ring down, the annular space on pushing away a section of thick bamboo and lower center tube upper portion is located to the deblocking cover.

The hydraulic mechanism is composed of two hydraulic cylinders, namely an upper hydraulic cylinder and a lower hydraulic cylinder, the upper cylinder body of the upper hydraulic cylinder is in threaded connection with the lower end of the push cylinder, an upper piston in the upper cylinder body is connected with the outer side of the lower portion of the lower central tube, the upper end of the lower cylinder body of the lower hydraulic cylinder is connected with the upper cylinder body, the upper portion of the lower piston in the lower cylinder body is connected with the lower portion of the upper piston, and the hydraulic cover is arranged in an annular space between the lower cylinder body and the lower piston.

The piston is in a variable-diameter cylinder shape, a sealing ring group is arranged outside the large-diameter position at the upper end and forms sealing with the inner cavity of the cylinder body, and a thread buckle is arranged inside the piston and connected with the central pipe.

The upper seal group and the lower seal group are fixed with the central tube through a plurality of guide nails circumferentially arranged, and a plurality of upper seal blocks and a plurality of lower seal blocks are externally provided with vulcanized rubber layers.

A method for using a soluble packer comprises the steps of pressing a central pipe of the packer when the soluble packer is used, enabling high-pressure liquid to enter a space between a piston and a cylinder body through a liquid inlet hole in the central pipe, enabling the liquid to upwards push the cylinder body to enable a setting shear pin between the cylinder body and a hydraulic cover to be cut off, then enabling the cylinder body to push a push cylinder, enabling an annular hoop of a sealing mechanism to be broken through applying force to the sealing mechanism through a top ring, enabling the annular hoop to outwards expand the diameter and climb onto a cone to form a large-diameter sealing mechanism, enabling a lock catch on the lower portion of the push cylinder to be meshed with a locking buckle on an unlocking sleeve at the same time to complete a locking function, and completing setting of the packer.

When the packer is unpacked, the central pipe of the packer is lifted upwards, the unpacking shear pin on the unpacking sleeve is cut off, the locking function is invalid, and the packer is unpacked; when the sealing mechanism and the cone are dissolved, the packer is completely unsealed, and the shaft can be smoothly taken out.

The invention has the beneficial effects that:

the soluble packer provided by the invention can be provided with a plurality of hydraulic cylinders according to the setting force, and a sealing mechanism is formed by adopting the movement of the mechanism, so that the setting force is small, and the control is accurate; the setting shear pin is sheared through hydraulic pressure, and the locking mechanism locks the setting shear pin to finish setting; when the deblocking, make the deblocking shear pin cut off through lifting the center tube, the locking function is inefficacy, and the deblocking process is smooth.

The soluble packer sealing mechanism adopts a soluble metal main body for sealing, and a rubber layer for auxiliary sealing, so that the soluble packer sealing mechanism has high bearing capacity, is not influenced by underground high temperature and has high reliability. After the operation is finished, the soluble material is made and can be fully dissolved, so that the packer can be smoothly and thoroughly unsealed, and the smoothness of a shaft is ensured.

The following will be described in further detail with reference to the accompanying drawings.

Drawings

FIG. 1 is a schematic top view of an embodiment of the packer of the present invention;

FIG. 2 is a schematic view of the lower part of FIG. 1;

FIG. 3 is a schematic structural view of one embodiment of the packer sealing mechanism of the present invention;

FIG. 4 is a schematic diagram of a soluble packer multi-stage sliding sleeve fracturing string application of the present invention.

In the figure: 1. an upper joint; 2. an upper center tube; 3. an adjusting ring; 4. an upper seal assembly seat; 5. an upper seal group; 501. an upper sealing block; 502. an upper annular hoop; 503. a vulcanized rubber layer; 6. a cone; 601. a conical vulcanized rubber layer; 7. a lower seal group; 701. a lower seal block; 702. a lower annular hoop; 703. a vulcanized rubber layer; 8. a lower seal group seat; 9. a top ring; 10. a lower center tube; 11. unsealing the shear pins; 12. unpacking; 13. a push cylinder; 14. an upper cylinder body; 15. an upper piston; 16. a lower cylinder body; 17. a lower piston; 18. a hydraulic cover; 19. a guide pin; 20. a locking buckle; 21. the upper sealing ring group I; 22. an upper sealing ring group II; 23. the lower sealing ring group I; 24. a second lower sealing ring group; 25. setting the shear pin; 26. a liquid inlet; 27. an external thread; 28. locking; 29. a constant pressure sand blower; 30. a first-stage sliding sleeve seat I; 31. a soluble packer I; 32. a first soluble hydraulic anchor; 33. a first-stage sliding sleeve II; 34. a first secondary sliding sleeve seat; 35. a soluble packer II; 36. a second soluble hydraulic anchor; 37. a second sliding sleeve; 38. a soluble packer III; 39. a third soluble hydraulic anchor; 40. and (4) an oil pipe.

Detailed Description

The following description of the embodiments of the present invention is provided for illustrative purposes, and other advantages and effects of the present invention will become apparent to those skilled in the art from the present disclosure.

The exemplary embodiments of the present invention will now be described with reference to the accompanying drawings, however, the present invention may be embodied in many different forms and is not limited to the embodiments described herein, which are provided for complete and complete disclosure of the present invention and to fully convey the scope of the present invention to those skilled in the art. The terminology used in the exemplary embodiments illustrated in the accompanying drawings is not intended to be limiting of the invention. In the drawings, the same units/elements are denoted by the same reference numerals.

Unless otherwise defined, terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Further, it will be understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense.

Example 1:

the embodiment provides a soluble packer, which comprises an upper joint 1 and a central tube, wherein the lower end of the upper joint 1 is connected with the outer wall of the central tube, an adjusting ring 3 is arranged outside the upper joint 1, a sealing mechanism and a top ring 9 are sequentially sleeved outside the central tube from top to bottom, a cone 6 is arranged in the middle of the sealing mechanism, an annular hoop is arranged on the sealing mechanism, a push cylinder 13 is connected below the top ring 9, a hydraulic mechanism is connected below the push cylinder 13, a liquid inlet 26 communicated with the hydraulic mechanism is arranged on the central tube, and the lower end of the hydraulic mechanism is fixedly connected with a hydraulic cover 18 through a setting shear pin 25;

the center tube is fixed with deblocking cover 12 through deblocking shear pin 11, deblocking cover 12 outside is equipped with locking buckle 20, pushing cylinder 13 lower part is equipped with hasp 28, the left lower part of locking buckle 20 is located to hasp 28, locking buckle 20 and hasp 28 phase-match, sealing mechanism and cone 6 all adopt magnesium aluminum alloy soluble material.

The soluble packer sealing mechanism adopts a soluble metal main body for sealing, and a rubber layer for auxiliary sealing, so that the soluble packer sealing mechanism has high bearing capacity, is not influenced by underground high temperature and has high reliability. The setting shear pin 25 is sheared through hydraulic pressure, and is locked by a locking mechanism to finish setting; when the deblocking, make deblocking shear pin 11 cut off through lifting the center tube, the locking function is invalid, and the deblocking process is smooth.

Example 2:

on the basis of embodiment 1, this embodiment provides a soluble packer, hydraulic pressure mechanism is a hydraulic cylinder or a plurality of hydraulic cylinders that connect gradually from top to bottom, and the hydraulic cylinder includes the piston in cylinder body and the cylinder body, the cylinder body links firmly through setting shear pin 25 with hydraulic pressure lid 18.

The hydraulic cylinder can be only one and is a single hydraulic cylinder packer, and when the setting force can not meet the requirement, two, three or a plurality of hydraulic cylinders can be respectively arranged to form multistage hydraulic cylinder packers such as a second-stage hydraulic cylinder, a third-stage hydraulic cylinder and the like.

Example 3:

on the basis of embodiment 1 or 2, this embodiment provides a soluble packer, sealing mechanism includes upper seal group 5 and lower seal group 7, upper seal group 5 is installed on upper seal group seat 4, lower seal group 7 is installed on lower seal group seat 8, upper seal group 5 includes a plurality of upper seal blocks 501, lower seal group 7 includes a plurality of lower seal blocks 701, upper seal group seat 4, upper seal block 501, lower seal block 701 and lower seal group seat 8 set gradually from last to bottom.

As shown in fig. 1, the upper seal group 5 and the lower seal group 7 are respectively installed in the upper seal group 5 and the lower seal group seat 8 through installation grooves, and the upper seal group seat 4, the upper seal group 5, the cone 6, the lower seal group 7, the lower seal group seat 8 and the top ring 9 are sequentially installed on the central pipe.

The push cylinder 13 is pushed by the hydraulic mechanism to move upwards, force is applied to the upper sealing group 5 and the lower sealing group 7, the sealing mechanism breaks the annular hoop, the upper sealing block 501 of the upper sealing group 5 and the lower sealing block 701 of the lower sealing group 7 expand outwards to climb the upper cone 6, and the upper sealing block and the lower sealing block are inserted together to form the large-diameter sealing mechanism.

Example 4:

on the basis of embodiment 1 or 2, the present embodiment provides a soluble packer, the base pipe comprises an upper base pipe 2 and a lower base pipe 10, the top end of the lower base pipe 10 is connected with the bottom end of a top ring 9, and an unpacking sleeve 12 is arranged in an annular space between a pushing cylinder 13 and the upper part of the lower base pipe 10.

As shown in fig. 2, the lower central tube 10 is in threaded connection with the upper central tube 2, the push cylinder 13 is in threaded connection with the top ring 9 and is sleeved outside the lower central tube 10, the cylinder body is connected with the push cylinder 13, the piston is connected with the lower central tube 10, and the lower end of the cylinder body seals an annular space between the cylinder body and the piston through a hydraulic cover 18.

Example 5:

on the basis of embodiment 2 or 3, the present embodiment provides a soluble packer, the hydraulic mechanism is two hydraulic cylinders, which are an upper hydraulic cylinder and a lower hydraulic cylinder, an upper cylinder 14 of the upper hydraulic cylinder is in threaded connection with the lower end of a push cylinder 13, an upper piston 15 in the upper cylinder 14 is connected with the outer side of the lower portion of a lower central tube 10, the upper end of a lower cylinder 16 of the lower hydraulic cylinder is connected with the upper cylinder 14, the upper portion of a lower piston 17 in the lower cylinder 16 is connected with the lower portion of the upper piston 15, and a hydraulic cover 18 is disposed in an annular space between the lower cylinder 16 and the lower piston 17.

As shown in figure 2, the lower end of the upper joint 1 is externally buckled with an adjusting ring 3, the inner end is buckled with an upper central pipe 2, and the upper central pipe 2, a lower central pipe 10, an upper piston 15 and a lower piston 17 are sequentially connected. When high-pressure liquid is pressurized, pressure acts on the upper piston 15 and the lower piston 17 to drive the central pipe to move downwards, the upper joint 1 applies force to the upper sealing group 5 to break an upper annular hoop 502 on the upper sealing group 5, so that the upper sealing group 5 expands outwards (downwards) to climb the upper cone 6, when the upper piston 15 and the lower piston 17 move to the limit positions, the upper joint acts on the hydraulic cover 18 to shear the seat sealing shear pin 25, then the liquid pushes the lower cylinder 16 and the upper cylinder 14 to push the push cylinder 13, the push cylinder 13 applies force to the lower sealing group 7 to break a lower annular hoop 702 on the lower sealing group 7, and a lower sealing block 701 of the lower sealing group 7 expands outwards (upwards) to climb the upper cone 6 to form a large-diameter sealing mechanism.

Example 6:

on the basis of embodiment 1, the present embodiment provides a soluble packer, which comprises an upper joint 1, an upper central pipe 2, an adjusting ring 3, an upper seal group seat 4, an upper seal group 5, a cone 6, a lower seal group 7, a lower seal group seat 8, a top ring 9, a lower central pipe 10, a deblocking shear pin 11, a deblocking sleeve 12, a push cylinder 13, a hydraulic cylinder and a hydraulic cover 18.

The lower end internal thread of the upper joint 1 is buckled and is connected with an upper central tube 2, the external thread 27 is buckled and is connected with an adjusting ring 3, an upper seal group 5, a lower seal group 7 is respectively arranged in an upper seal group seat 4 and a lower seal group seat 8 through mounting grooves, the upper seal group seat 4, the upper seal group 5, a cone 6, the lower seal group 7, the lower seal group seat 8, a top ring 9 is sequentially arranged on the upper central tube 2, a lower central tube 10 is in threaded connection with the upper central tube 2, a pushing cylinder 13 is in threaded connection with the top ring 9, the lower central tube 10 is sleeved with the pushing cylinder 13, a piston in the cylinder is connected with the lower central tube 10, and the lower end of the cylinder seals the annular space between the cylinder and the piston through a hydraulic cover 18.

As shown in fig. 3, the upper seal group 5 and the lower seal group 7 are respectively composed of a plurality of upper seal blocks 501 and lower seal blocks 701, the upper seal blocks 501 and the lower seal blocks 701 are respectively inserted into the upper seal seat and the lower seal seat through dovetails at the ends, the upper seal blocks 501 are radially constrained by the upper annular hoop 502, the lower seal blocks 701 are radially constrained by the lower annular hoop 702, and a layer of vulcanized rubber layer 503503 and 703 is respectively arranged outside the upper seal blocks 501 and the lower seal blocks 701. The upper sealing group seat 4 and the lower sealing group seat 8 are circumferentially positioned with the upper central tube 2 through guide nails 19. The outer circle of the middle part of the cone 6 is provided with a layer of cone vulcanized rubber 601.

As shown in fig. 2, the outer diameter of the lower central tube 10 has three reducing diameters, the minimum diameter section is at the lowest end, the lower end of the minimum diameter section has a thread buckle, the thread buckle is connected with the piston thread buckle, the annular space between the upper end and the pushing cylinder 13 has a deblocking sleeve 12, the deblocking sleeve 12 is fixed on the lower central tube 10 through a deblocking shear pin 11, and the deblocking sleeve 12 is provided with a locking buckle 20.

The pushing cylinder 13 is a cylinder, and the inner cylinder wall of the lower end of the pushing cylinder 13 is provided with a locking buckle 20 which is matched with the locking buckle 20 on the unsealing sleeve 12.

The cylinder body is in a diameter-variable cylinder shape, a thread buckle is arranged outside the small diameter position of the upper end of the cylinder body and used for being connected with the push cylinder 13, and a sealing ring group is arranged inside the cylinder body. The hydraulic cylinder can be only one and is a single hydraulic cylinder packer, and when the setting force cannot meet the requirement, two, three and a plurality of hydraulic cylinders can be arranged to form multistage hydraulic cylinder packers such as a second-stage hydraulic cylinder and a third-stage hydraulic cylinder.

The piston is in a reducing cylinder shape, a sealing ring group is arranged outside the large-diameter part at the upper end and forms sealing with the inner cavity of the cylinder body, and a thread buckle is arranged inside the piston and connected with the lower central tube 10.

The hydraulic cover 18 is a reducing cylinder, an axial annular groove is arranged on the excircle of the upper part, a setting shear pin 25 is arranged in the hydraulic cover and is fixed with the cylinder body through the setting shear pin 25, and a thread buckle is arranged in the lower part of the hydraulic cover and is connected with an external thread 27 port of the piston.

The sealing mechanism of the packer comprises a sealing group seat, a sealing block and a cone 6 which are all made of magnesium-aluminum alloy materials, and the dissolution time of the materials can be adjusted according to construction requirements.

Example 7:

on the basis of embodiment 1, the present embodiment provides a soluble packer, as shown in figures 1 and 2,

the sealing device comprises an upper joint 1, an upper central pipe 2, an adjusting ring 3, an upper sealing group seat 4, an upper sealing group 5, a cone 6, a lower sealing group 7, a lower sealing group seat 8, a top ring 9, a lower central pipe 10, a deblocking shear pin 11, a deblocking sleeve 12, a push cylinder 13, an upper cylinder body 14, an upper piston 15, a lower cylinder body 16, a lower piston 17, a hydraulic cover 18, a guide pin 19 and a locking buckle 20.

In the present embodiment, the number of the hydraulic cylinders is two. The upper central tube 2, the lower central tube 10, the upper piston 15 and the lower piston 17 are sequentially connected, the upper cylinder and the lower central tube are sealed through an upper sealing ring group I21, the upper piston and the upper cylinder are sealed through an upper sealing ring group II 22, the lower cylinder and the lower part of the upper piston are sealed through a lower sealing ring group I23, the lower piston and the lower cylinder are sealed through a lower sealing ring group II 24, the upper sealing group seat 4 props against the adjusting ring 3 and is sleeved on the upper central tube 2, the upper sealing group 5, the cone 6, the lower sealing group 7, the lower sealing seat and the top ring 9 are sequentially sleeved downwards, the top ring 9 is sequentially connected with the pushing cylinder 13, the upper cylinder 14 and the lower cylinder 16 downwards in a threaded mode, the hydraulic cover 18 props against the lower cylinder 16 and is connected with threads on the lower piston 17, the deblocking sleeve 12 is fixed on the lower central tube 10 through a deblocking shear pin 11, and the deblocking sleeve 12 is provided with a locking buckle 20 through an external thread 27.

When the packer central pipe is used, the packer central pipe is pressed, high-pressure liquid enters the space between the upper piston 15 and the upper cylinder 14 and the space between the lower piston 17 and the lower cylinder 16 through the two liquid inlets 26 on the central pipe respectively, the liquid pushes the two-stage cylinders, the setting shear pin 25 between the lower cylinder 16 and the hydraulic cover 18 is sheared off, the cylinders push the push cylinders 13, the push cylinders 13 apply force to the upper sealing group 7 and the lower sealing group 7, the annular hoops are broken, the upper sealing block 701 and the lower sealing block 701 expand outwards to climb the upper cone 6 to form a large-diameter sealing mechanism, meanwhile, the lock catches 28 at the lower parts of the push cylinders 13 are meshed with the lock catches 20 to complete the locking function, and the packer setting is finished.

When deblocking, the upper packer center tube, the deblocking shear pin 11 on the deblocking sleeve 12 is cut off, the locking mechanism is invalid, and the packer is deblocked. Meanwhile, the upper sealing block 501, the lower sealing block 701 and the cone 6 of the packer are dissolved, so that the packer is completely unsealed.

Example 8:

when the soluble packer is used, the central pipe of the packer is pressed, high-pressure liquid enters a space between a piston and a cylinder body through a liquid inlet 26 on the central pipe, the liquid pushes the cylinder body upwards to cut a setting shear pin 25 between the cylinder body and a hydraulic cover 18, then the cylinder body pushes a push barrel 13, the push barrel 13 exerts force on a sealing mechanism through a top ring 9 to break an annular hoop of the sealing mechanism, the annular hoop expands outwards to climb an upper cone 6 to form a large-diameter sealing mechanism, meanwhile, a lock catch 28 on the lower portion of the push barrel 13 is meshed with a lock catch 20 on a deblocking sleeve 12 to complete a locking function, and setting of the packer is finished.

When the packer is unpacked, the central pipe of the packer is lifted upwards, the unpacking shear pins 11 on the unpacking sleeve 12 are sheared, the locking function is invalid, and the packer is unpacked; when the sealing mechanism and the cone 6 are dissolved, the packer is completely unsealed, and the shaft can be smoothly taken out.

Example 9:

the soluble packer is used for a multi-stage sliding sleeve fracturing string, and comprises a constant pressure sand blower 29 at the lowest end of a tubing 40, a first sliding sleeve seat 30, a first soluble packer 31, a first soluble hydraulic anchor 32, a second first sliding sleeve 33, a first second sliding sleeve seat 34, a second soluble packer 35, a second soluble hydraulic anchor 36, a second sliding sleeve 37, a third soluble packer 38 and a third soluble hydraulic anchor 39, which are shown in figure 4.

The method and principle of the string fracturing are as follows:

step one, according to the position of a perforation interval, a pipe column is lowered to a proper position of a shaft, so that a constant pressure sand blower 29 is arranged at a first section of perforation position, and a first-stage sliding sleeve two 33 and a second-stage sliding sleeve two 37 are respectively arranged at a second section of perforation position and a third section of perforation position;

step two, the oil pipe 40 is pressed, and all soluble packers are set;

continuing to pressurize the oil pipe 40, opening the constant-pressure sand blaster 29 and performing first-stage fracturing;

step four, after the first section fracturing is finished, throwing a first-stage fracturing ball at the wellhead, opening a second first-stage fracturing sliding sleeve, simultaneously dropping the fracturing ball on the first-stage sliding sleeve seat 30, sealing the fractured first section, and fracturing the second section;

step five, completing the fracturing of the third section in sequence;

and step six, after fracturing is finished, blowout prevention is performed on a wellhead, the fracturing string can be used as a production string to be left in the well, and the fracturing string can be taken out after the soluble packer and the hydraulic anchor soluble component are dissolved and the upper body string and the packer are unsealed according to requirements.

As shown in FIG. 3, on the basis of the improvement, the first-stage sliding sleeve seat 30, the first soluble packer 31, the first soluble hydraulic anchor 32 and the second first-stage sliding sleeve 33 are used as one group, and multiple groups, for example, 5 groups can be designed according to the requirements of the fracturing interval, so that 6-stage fracturing can be completed. Under the influence of the displacement and the inner diameter of the sliding sleeve, when all the intervals cannot be fractured by one time of the string, multiple times of fracturing strings can be set.

The soluble packer can be used for multilayer, multistage fracturing and acidizing of oil and gas wells, can also be used for separate layer water injection, can be used for immobile string construction, can also be used for tripping strings, can be used for cased wells and open-hole wells, and has a wide application range.

The above examples are merely illustrative of the present invention and should not be construed as limiting the scope of the invention, which is intended to be covered by the claims and any design similar or equivalent to the scope of the invention.

Claims (7)

1. The utility model provides a soluble packer, includes top connection (1) and center tube, top connection (1) lower extreme and center tube outer wall connection, its characterized in that: the upper connector (1) is externally provided with an adjusting ring (3), the central tube is sequentially sleeved with a sealing mechanism and a top ring (9) from top to bottom, the middle part of the sealing mechanism is provided with a cone (6), the sealing mechanism is provided with an annular hoop, the top ring (9) is connected with a push cylinder (13) below, the push cylinder (13) is connected with a hydraulic mechanism below, the central tube is provided with a liquid inlet (26) communicated with the hydraulic mechanism, and the lower end of the hydraulic mechanism is fixedly connected with a hydraulic cover (18) through a setting shear pin (25);

the hydraulic mechanism is a hydraulic cylinder or a plurality of hydraulic cylinders which are sequentially connected from top to bottom, each hydraulic cylinder comprises a cylinder body and a piston in the cylinder body, the cylinder body is fixedly connected with a hydraulic cover (18) through a setting shear pin (25), and the lower end of the cylinder body seals an annular space between the cylinder body and the piston through the hydraulic cover (18);

an unpacking sleeve (12) is fixed on the central tube through an unpacking shear pin (11), a locking buckle (20) is arranged on the outer side of the unpacking sleeve (12), a lock catch (28) is arranged on the lower portion of the push cylinder (13), the lock catch (28) is arranged on the left lower portion of the locking buckle (20), the locking buckle (20) is matched with the lock catch (28), and the sealing mechanism and the cone (6) are made of magnesium-aluminum alloy soluble materials;

sealing mechanism includes upper seal group (5) and lower seal group (7), upper seal group (5) and lower seal group (7) are installed respectively on upper seal group seat (4) and lower seal group seat (8), upper seal group (5) includes a plurality of upper seal blocks (501), lower seal group (7) includes a plurality of lower seal blocks (701), upper seal group seat (4), upper seal block (501), lower seal block (701) and lower seal group seat (8) set gradually from last to lower.

2. A soluble packer as claimed in claim 1, wherein: the center tube includes center tube (2) and lower center tube (10), the top of center tube (10) meets with the bottom of apical ring (9) down, the annular space on pushing cylinder (13) and lower center tube (10) upper portion is located to the decapsulation cover (12).

3. A soluble packer as claimed in claim 1, wherein: the hydraulic mechanism is two hydraulic cylinders which are an upper hydraulic cylinder and a lower hydraulic cylinder respectively, an upper cylinder body (14) of the upper hydraulic cylinder is in threaded connection with the lower end of the push cylinder (13), an upper piston (15) in the upper cylinder body (14) is connected with the outer side of the lower portion of the lower central tube (10), the upper end of a lower cylinder body (16) of the lower hydraulic cylinder is connected with the upper cylinder body (14), the upper portion of a lower piston (17) in the lower cylinder body (16) is connected with the lower portion of the upper piston (15), and the hydraulic cover (18) is arranged in an annular space between the lower cylinder body (16) and the lower piston (17).

4. A soluble packer as claimed in claim 1, wherein: the piston is in a variable-diameter cylinder shape, a sealing ring group is arranged outside the large-diameter position at the upper end and forms sealing with the inner cavity of the cylinder body, and a thread buckle is arranged inside the piston and connected with the central pipe.

5. A soluble packer as claimed in claim 1, wherein: the upper sealing group (5) and the lower sealing group (7) are fixed with the central tube through a plurality of guide nails (19) arranged circumferentially, and vulcanized rubber layers (503) are arranged outside the upper sealing blocks (501) and the lower sealing blocks (701).

6. The method of using a soluble packer as in claim 1, wherein: when the hydraulic sealing device is used, a central pipe of the packer is pressurized, high-pressure liquid enters a position between the piston and the cylinder body through a liquid inlet (26) in the central pipe, the liquid pushes the cylinder body upwards to cut a setting shear pin (25) between the cylinder body and a hydraulic cover (18), then the cylinder body pushes the push cylinder (13), the push cylinder (13) exerts force on the sealing mechanism through the top ring (9), an annular hoop of the sealing mechanism is broken, the diameter of the annular hoop is expanded outwards to climb the cone (6) to form a large-diameter sealing mechanism, meanwhile, a lock catch (28) at the lower part of the push cylinder (13) is meshed with a locking buckle (20) on the deblocking sleeve (12), the locking function is completed, and the setting of the packer is finished.

7. The method of using a soluble packer as in claim 6, wherein: when the packer is unpacked, the central pipe of the packer is lifted upwards, the unpacking shear pins (11) on the unpacking sleeve (12) are sheared, the locking function is invalid, and the packer is unpacked; when the sealing mechanism and the cone (6) are dissolved, the packer is completely unsealed, and the well can be smoothly taken out.

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