WO2016101374A1

WO2016101374A1 - Bridge plug having large drift diameter and setting method thereof

Info

Publication number: WO2016101374A1
Application number: PCT/CN2015/071068
Authority: WO
Inventors: 叶登胜; 宁世品; 梅鹏
Original assignee: 杰瑞能源服务有限公司
Priority date: 2014-12-26
Filing date: 2015-01-20
Publication date: 2016-06-30
Also published as: CN104632126A; CN104632126B

Abstract

A bridge plug having a large drift diameter comprises: an upper joint (1), a central pipe (7), a guide shoe head (12), and a bridge plug assembly; the upper joint and the guide shoe head are annular, the upper joint fixedly sleeves an outer side of one end of the central pipe, the guide shoe head fixedly sleeves the outer side of the other end of the central pipe, the bridge plug assembly sleeves the outer side of a middle section of the central pipe and is located between the upper joint and the guide shoe head, an apparatus for fixedly connecting to a pull rod(16) sleeved within the bridge plug is disposed on the guide shoe head, a soluble sphere base is disposed at the end of the central pipe proximal to the upper joint, and the central pipe is a drillable metal unit. The present invention also relates to a setting method of the bridge plug having a large drift diameter. The bridge plug having the large drift diameter eliminates a drilling and grinding step of the bridge plug and avoids the problems of a long construction time period, a high operation cost, and a large construction risk caused by the drilling and grinding step, such that the bridge plug is easier to use and faster to construct.

Description

Large-diameter bridge plug and its setting method

This application claims priority to Chinese Patent Application No. 201410834503.9, filed on Dec. 26, 2014, entitled "A large-diameter bridge plug and its setting method", the entire contents of which are incorporated by reference. In this application.

Technical field

The invention relates to the technical field of petroleum industry, in particular to a large-diameter bridge plug and a method for setting the same.

Background technique

In the petroleum industry, it is common to use packers or bridge plugs to achieve the process of sealing layers. The function of the bridge plug is to seal the oil and gas wells. It has the characteristics of less construction process, accurate sealing position and large scale of fracturing.

With the development of oil and gas fields and the continuous consumption of energy, unconventional oil and gas will become the direction of future oil and gas energy. The composite bridge plug multi-layer fracturing technology is the main technology for the development of unconventional oil and gas such as shale gas reservoirs at home and abroad. This technology is widely used because of its simple and limited tool string. After the bridge is drilled and drilled, the wellbore can be ensured, and the subsequent process string can be facilitated. Due to the above advantages, the composite bridge plug has many sub-stages and large-scale low-permeability oil and gas wells and shale gas. Widely used in the well.

However, in the subsequent use of the composite bridge plug, in order to ensure the smooth flow of oil and gas, it is usually necessary to use the method of drilling and grinding to remove the whole of the bridge plug, the drilling process takes a long time, the drill cutting cycle is difficult, and the drilling and grinding operations are difficult. The cost is high, so the limitation in the shale gas segmentation pressure reform is relatively large.

In summary, how to avoid the complicated drilling process of the bridge plug is a technical problem that needs to be solved by those skilled in the art.

Summary of the invention

In view of this, the object of the present invention is to provide a large-diameter bridge plug which does not need to be drilled in subsequent use, can significantly improve the construction efficiency of the bridge plug, and save the working time of the oil and gas well. Another object of the present invention is to provide a large-diameter bridge plug setting method.

To achieve the above object, the present invention provides the following technical solutions:

A large-diameter bridge plug, comprising an upper joint, a center tube, a lead-in head and a bridge plug assembly;

The upper joint is a ring member, and is fixedly sleeved on an outer side of one end of the center tube;

The central tube is a metal center tube, and a center of the center tube near the upper joint is provided with a soluble ball seat, and the center tube is a drillable metal piece;

The guiding shoe head is a ring member, and the fixing sleeve is sleeved on the outer side of the other end of the center tube, and the guiding shoe head is provided with a device for fixedly connecting with the pulling rod sleeved in the bridge plug;

The bridge plug assembly is sleeved on an outer side of the middle section of the center tube and between the upper joint and the toe cap.

Preferably, the bridge plug assembly comprises an end ring, a wristband, a slip, a slip seat and a rubber cylinder, all of which are sleeved on the outer side of the central tube; and one of the tapered end faces of the two ends of the rubber cylinder The wristband is a tapered sleeve, the tapered end surface of the wristband is attached to the tapered end surface of the rubber cylinder, and the wristband is a plastic wristband; The outer end of the tapered end face of the wristband is respectively sleeved with one of the end rings, wherein the other end of one of the end rings is fitted to the tapered end surface of the upper joint, and the other end of the other end ring is opposite to the card a tapered end surface of the tile seat is attached, the slip seat is connected to the center tube by a slip bearing; the other end surface of the slip seat is attached to the tapered end surface of the slip, kava One end of the non-tapered surface is in contact with one end of the lead shoe.

Preferably, the rubber cylinder comprises a main rubber cylinder and a secondary rubber cylinder; the main rubber cylinder and the secondary rubber cylinder are sleeved on an outer side of the central tube, and the secondary rubber cylinder is a tapered sleeve. The tapered inner side wall of the sub-cylinder is attached to the outer side wall of the lower end port of the main rubber cylinder, and the tapered outer wall of the sub-cylinder is attached to the tapered end surface of the wrist guard.

Preferably, further comprising an inverted tooth ring disposed between the inner wall of the upper joint and the outer wall of the center tube, the inner zigzag thread on the inner wall of the upper joint and the outer serration of the inverted tooth ring Threaded, the inner serration thread of the inverted ring is threaded with the outer serration of the center tube.

Preferably, the secondary rubber cylinders are disposed on both end faces of the main rubber cylinder, and the number of the secondary rubber cylinders is at least two.

Preferably, the upper joint is fixed to the center tube by an upper joint shearing nail, the upper joint shearing nail is disposed in a radial direction of the central tube, and the upper end of the upper joint is provided for connecting another bridge plug lower joint The claw structure is fixed to the pull rod by a throwing nail.

Preferably, the upper joint, the end ring, the slip seat, the slip and the lead shoe are all drillable metal pieces.

Preferably, the slip is an integral slip with a uniformly distributed stress set on an outer surface thereof a middle groove, a direction of the stress concentration groove is arranged along an axial direction of the slip, a radial opening groove is arranged on an end surface of the slip contacting the shoe head; and the slip is inserted into the toe cap A slot in one end is connected to the lead shoe.

A large-diameter bridge plug setting method for plugging oil and gas wells, wherein the method comprises:

Fixing the pull rod of the setting tool with the leading shoe head, aligning the pushing tube in the setting tool with the bridge plug, and the end surface thereof is in contact with the upper joint on the bridge plug, through the pull rod Positioning the toe cap and the center tube to fix the connection between the pull rod and the bridge plug;

Lowering the bridge plug to a predetermined position in the casing by a cable or coiled tubing;

Actuating the setting tool, the pushing cylinder pressing the end surface of the upper joint, the upper joint pressing the bridge assembly, sealing the annulus of the bridge plug and the casing, and anchoring The bridge plug disconnects the fixed connection of the pull rod and the lead shoe to separate the setting tool from the bridge plug;

And the setting tool separated from the bridge plug is raised on the ground, the soluble ball is placed on the soluble ball seat at one end of the upper joint, and the setting is completed; after the fracturing construction, after the fracturing construction, the The soluble spheres are dissolved by the formation fluid.

The utility model provides a large-diameter bridge plug, which is characterized in that the composite central pipe of the prior art is changed into a metal central pipe. Since the metal central pipe has high hardness and high strength, the thickness of the central pipe is reduced and the inner diameter is increased. It can also meet the strength requirements of the central tube. Therefore, the center tube provided by the present invention can be used to change the central tube having a smaller inner diameter and a thicker wall in the prior art to a metal central tube having a larger inner diameter and a thinner wall. During the use of the bridge plug, The larger inner tube inner diameter can meet the production needs, avoiding the drilling and grinding of the bridge plug before production; secondly, the metal central tube of the invention has better structural strength than the plastic central tube in the composite bridge plug. During the sealing process, the central tube will not be damaged due to the thinner and plastic characteristics of the tube, and the setting can be successfully completed to ensure the normal use of the bridge plug. Thirdly, in the subsequent use, it is necessary to further improve the transmission amount of the oil pipe by drilling the bridge plug, and the metal bridge plug is easily drilled.

It can be seen from the above technical solution that the large-diameter bridge plug provided by the invention can avoid the drilling process of the bridge plug, avoids the problems of long construction period, high operation cost and large construction risk caused by drilling and grinding, so that the bridge plug It is easier to use and faster to construct.

DRAWINGS

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following will The drawings used in the embodiments or the description of the prior art are briefly introduced. It is obvious that the drawings in the following description are merely embodiments of the present invention, and no one skilled in the art Further drawings may also be obtained from the drawings provided.

1 is a schematic structural view of a specific embodiment of a large-diameter bridge plug according to the present invention;

2 is a schematic structural view of a large-diameter bridge plug according to the present invention after loading a soluble ball;

3 is a schematic structural view of an upper joint in a specific embodiment of a large-diameter bridge plug according to the present invention;

4 is a schematic structural view of a shoe head in a specific embodiment of a large-diameter bridge plug according to the present invention;

FIG. 5 is a flow chart of a method for setting a large-diameter bridge plug according to the present invention.

Among them, 1 is the upper joint, 2 is the upper joint shearing nail, 3 is the inverted toothed ring, 4 is the end ring, 5 is the auxiliary rubber cylinder, 6 is the main rubber cylinder, 7 is the center tube, 8 is the wristband, 9 is the card Tile seat, 10 is the Kava seat nail, 11 is the slip, 12 is the lead, 13 is the throwing nail, 14 is the soluble ball, 15 is the push tube, 16 is the pull rod.

detailed description

The technical solutions in the embodiments of the present invention are clearly and completely described in the following with reference to the accompanying drawings in the embodiments of the present invention. It is obvious that the described embodiments are only a part of the embodiments of the present invention, but not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative efforts are within the scope of the present invention.

The core of the invention is to provide a large-diameter bridge plug which does not need to be drilled during use, can significantly improve the operation efficiency of the bridge plug, and save the operation time of the oil and gas well. Another core of the present invention is to provide a large-diameter bridge plug setting method.

Please refer to FIG. 1 and FIG. 2 . FIG. 1 is a schematic structural diagram of a specific embodiment of a large-diameter bridge plug according to the present invention. FIG. 2 is a schematic diagram of a large-diameter bridge plug according to the present invention. Schematic diagram of the structure after melting the ball.

In a specific embodiment, the bridge plug provided by the present invention includes an upper joint 1, a center tube 7, a lead shoe 12, and a bridge plug assembly.

The upper joint 1 is a sleeve-like annular member, and one end of the joint 1 is fixedly sleeved on the outer side of one end of the central tube 7. Please refer to FIG. 3. FIG. 3 is a schematic structural diagram of an upper joint in a specific embodiment of a large-diameter bridge plug according to the present invention. One end face of the upper joint 1 is used for contact with the pusher cylinder 15 in the setting device, and the pressing force of the pusher cylinder 15 for the upper joint 1 is transmitted to other components of the bridge plug, and the setting can be achieved. The end surface of the upper joint 1 in contact with the push cylinder 15 has a snap-fit structure for engaging with the lower joint of the other bridge plug to prevent the lower joint from rotating during drilling.

The center tube 7 is a metal center tube having a large inner diameter. The center tube 7 is characterized by a large inner diameter and an outer diameter, and the center tube has a thin wall thickness, and the center tube 7 is a drillable metal member. Wherein, the center tube 7 is disposed near one end of the upper joint 1 with a soluble ball seat, usually a spherical seat or a cone seat, for placing a soluble ball.

Please refer to FIG. 4. FIG. 4 is a schematic structural view of a shoe head according to a specific embodiment of a large-diameter bridge plug according to the present invention.

The toe cap 12 is a ring member that is fixedly sleeved on the outer side of the other end of the center tube 7, and the toe cap 12 is fixedly coupled to the tie rod 16 that is sleeved in the bridge plug.

Alternatively, the upper joint 1 and the center pipe 7 are fixed by the upper joint shearing nail 2, and the upper joint shearing nail 2 is inserted from the outer peripheral surface of the upper joint 1, and inserted into the center pipe 7, fixing the both in the radial direction.

Optionally, the toe cap 12 and the tie rod 16 sleeved in the bridge plug are fixedly connected by the throwing hand nail 13 inserted from the outer peripheral surface of the toe cap 12 and inserted into the pull rod 16 in the radial direction. The lead shoe 12 and the tie rod 16 are relatively fixed.

Optionally, the toe cap 12 is a ring-shaped member having a stepped structure that is in contact with the center tube 7 for engaging the center tube 7, and the thinner side of the tube head 12 is passed through a screw or a thread. The central tube 7 is connected and fixed, and the thicker side of the tube head 12 is connected to the rod 16 by the throwing nail 13 . Optionally, the foregoing connection manner may also adopt other fixed manners.

The bridge plug assembly is sleeved on the outside of the middle section of the central tube 7 and is located between the upper joint 1 and the leading toe 12. The bridge plug assembly mainly comprises a rubber cylinder, an end ring 4, a wrist guard 8, a slip seat 9 and a slip 11 which are all sleeved on the outer side of the center tube 7 and arranged in order in the axial direction.

The rubber cylinder is a sleeve type component, and both end faces of the rubber cylinder are tapered surfaces, and the tapered surface direction faces the outer side of the rubber cylinder, which is simply referred to as an outer tapered surface, and correspondingly, the tapered surface of the tapered surface toward the inner side of the rubber cylinder is simply referred to as inner The tapered surface, which is described below by the abbreviation, is placed on the outer side of the center of the center rod 7.

Optionally, the inner wall of the rubber cylinder has an annular groove, and when the rubber cylinder is subjected to the axial pressing force, Helps the expansion of the cartridge to the radially outer side.

The wristband 8 is a sleeve with a taper and is located between the rubber cylinder and the end ring 4. A wristband 8 is disposed on each of the tapered end faces of the rubber cylinder, and the tapered end surface of the wristband 8 is attached to the rubber cylinder. On the tapered end face, the other tapered end face of the wristband 8 is fitted to the inner end face of the end ring 4, which is a plastic wristband.

The end ring 4 is a tapered ring member, one end surface of which is an inner tapered surface and the other end surface is an outer tapered surface. An end ring 4 is disposed on each side of the two wristbands 8, and the outer tapered surface of the end ring 4 near the upper joint 1 is in close contact with the tapered surface of the upper joint 1 with the internally threaded end; the other end ring 4 is externally The tapered surface is used to fit the inner tapered surface at one end of the slip seat 9.

The slip seat 9 is a sleeve type component, and one end surface has an inner tapered surface toward the inner side of the slip seat, and the other end surface has a slope surface facing the outer side of the slip seat. The slip 11 is an annular member having an inner tapered surface at one end, the outer cylindrical surface of the annular member being provided with a serrated surface for engaging the sleeve, and the other end surface of the slip 11 for inserting one end of the toe cap 12. The slip seat 9 is connected to the center tube 7 by the slip holder 10, and the other end face of the slip seat 9 is fitted to the tapered end surface of the slip 11.

Optionally, the bridge plug assembly provided in the above embodiment includes a rubber cylinder, and the number of the rubber cylinders is not unique, and the rubber cartridge can be divided into different structures and shapes according to the different functions at the time of setting. cylinder.

Alternatively, a main cartridge 6 and a sub-cartridge 5 may be provided to mount the sub-cartridge 5 on the lower end port of the main cartridge 6. Further, two sub-cartridges 5 may be disposed, which are respectively sleeved at both ends of the main rubber cylinder 6. The rubber cartridge provided in this embodiment comprises a main rubber cylinder 6 and two sub-plastic cartridges 5; the main rubber cylinder 6 and the sub-plastic cartridge 5 are sleeved on the outer side of the central tube 7, and the sub-cartridge 5 is a tapered sleeve. The tapered inner side wall of the sub-cylinder 5 is attached to the tapered outer side wall of the port of the main rubber tube 6, and the tapered outer wall of the sub-cylinder 5 is attached to the inner tapered surface of the end surface of the end ring 4.

The overall connection and arrangement of the above-mentioned bridge plug assembly structure is as follows: one end of the upper joint 1 is closely fitted with the outer tapered surface of the end ring 4, and the movement of the end ring 4 is restricted in the axial direction, and the other end of the end ring 4 is inside. The tapered surface is in close contact with the outer tapered surface of the wristband 8. The inner tapered surface of the wristband 8 closely fits the outer tapered surface of the secondary rubber cylinder 5, and the inner tapered surface of the secondary rubber cylinder 5 closely fits the outer tapered surface of the main rubber cylinder 6. . The end ring 4, the wristband 8, the sub-cartridge 5 and the main rubber cylinder 6 in turn limit the movement of the latter in the axial direction. At the other end of the main rubber cylinder 6, the sub-cartridge 5, the wristband 8, and the end ring 4 are sequentially connected in the same manner. The outer tapered surface of the end ring 4 is in contact with the inner tapered surface of the slip seat 9. The threaded hole in the slip seat 9 is facing the shearing groove of the center rod 7, The slip seat 9 is fixed on the central tube 7 by a plurality of slip bearing nails 10. The outer tapered surface of the other end of the slip seat 9 is closely engaged with the tapered surface of the slip 11 , and the slip 11 is not inserted into one end of the tapered surface. One end of the toe cap 12 is brought into contact with it.

Optionally, the bridge plug further includes an inverted ring 3, and the inverted ring 3 is sleeved between the inner wall of the upper joint 1 and the outer wall of the central tube 7. At a position where the upper joint 1 is connected to the center pipe 7, a structure for connecting the inverted ring gear 3 is provided correspondingly.

Specifically, at the joint, the inner wall of the upper joint 1 is provided with an inner zigzag thread, and the outer wall of the center pipe 7 is provided with an outer serrated thread. An outer serration thread matching the inner serrated thread of the upper joint 1 is disposed on the outer cylindrical surface of the inverted toothed ring 3, and an outer serrated thread of the central tube 7 is provided on the inner cylindrical surface of the inverted toothed ring 3 Internal serrated thread. The upper joint 1, the inverted ring gear 3 and the central tube 7 are screwed and fixed relatively to prevent unsealing of the rubber cylinder and the slip.

In order to ensure the setting effect, the inner and outer sides of the inverted toothed ring 3 are provided with zigzag threads, and the internal threads of the inverted toothed ring 3 are opposite to the serrations of the external threads on the central tube 7, and the external thread of the inverted toothed ring 3 and the upper joint The serrations of the internal threads of 1 are opposite. The upper joint 1 and the inverted toothed ring 3 are moved together along the serrations on the center tube 7 when set. When the cartridge and the slip 11 are seated, the upper joint 1 and the inverted ring 3 are moved into position. Because the internal thread of the inverted toothed ring 3 and the serration of the external thread of the central tube 7 mesh with each other, the inverted toothed ring 3 can no longer move upwards and return to the original position; similarly, the upper joint 1 is not moved to the original position. The position, therefore, ensures that the cartridge will not be unsealed.

Alternatively, the above three can also be fixed by other thread forms.

Optionally, in order to ensure the setting of the rubber cylinder, the auxiliary rubber cylinders 5 are disposed on the two end faces of the main rubber cylinder 6, and the number of the secondary rubber cylinders 5 is at least two, respectively placed in the main rubber cylinders 6 On both sides.

Optionally, in order to prevent the bridge plug from being used for drilling or removal, the upper joint 1, the end ring 4, the slip seat 9, the slip 11 and the toe cap 12 in the bridge plug are assembled by metal parts. Metal parts are easy to drill and provide convenience for the drilling process.

Optionally, the slips 11 are integral slips, and the outer surface thereof is provided with a uniformly distributed stress concentration groove. The direction of the stress concentration grooves is arranged along the axial direction of the slips 11 , and the slips 11 are in contact with the lead-in heads 12 . The end surface is provided with a radial opening groove, and the above-mentioned stress concentration groove and the opening groove are arranged to facilitate uniform cracking of the slip.

In the present invention, a metal center tube is used as the center tube 7 of the bridge plug, because the strength of the metal center tube is superior to that of the ordinary composite material center tube, and the strength of the center tube 7 is directly in the setting process. Affecting the setting effect, further, because the strength is ensured, the wall thickness of the central tube 7 can be reduced, the inner and outer diameters of the central tube 7 can be increased, and the inner diameter of the central tube 7 can be increased to make the bridge plug The inner diameter becomes larger. In the subsequent use, the larger inner diameter of the bridge plug can satisfy the oil and gas transmission between the oil layers, and the bridge plug is not required to be removed by the drilling method, thereby avoiding the difficulty caused by the drilling step.

In the present invention, the central pipe 7 of the large-diameter bridge plug has high strength, and the wall of the central pipe 7 can be thinned and the inner diameter becomes larger. Since the inner diameter of the bridge plug is determined by the inner diameter of the central pipe 7, the bridge with a larger inner diameter is In operation, the need to drill the bridge plug can meet the requirements of oil and gas transmission, eliminating the prior art process of drilling and grinding the bridge plug, and avoiding the complicated process of drilling and grinding.

In addition to the bridge plug provided by the above embodiments, the present invention also provides a method for setting a large-diameter bridge plug. Please refer to FIG. 2 and FIG. 5. FIG. 2 is a specific embodiment of a large-diameter bridge plug according to the present invention. A schematic diagram of a structure after loading a soluble ball; FIG. 5 is a flow chart of a method for setting a large-diameter bridge plug according to the present invention. The method includes the following steps:

Step s101: Fix the pull rod 16 of the setting tool and the toe cap 12, align the pushing tube 15 in the setting tool with the bridge plug, and the end surface thereof is in contact with the joint 1 on the bridge plug, and the toe cap is guided by the rod 16 The position of the center tube 7 is fixed to 12, and the connection of the tie rod 16 to the bridge plug is realized.

Step s102: Lower the bridge plug to a predetermined position in the casing through a cable or a coiled tubing.

Step s103: start the setting tool, push the cylinder 15 to press the end face of the joint 1, the upper joint 1 squeezes the bridge plug assembly, seals the annulus of the bridge plug and the casing, and anchors the bridge plug, disconnects the tie rod 16 and The fixed connection of the toe cap 12 separates the setting tool from the bridge plug.

Step s104: Put the setting tool separated from the bridge plug on the ground, place the soluble ball 14 on the soluble ball seat on one end of the upper joint 1, and complete the setting; perform the fracturing construction, and after the fracturing, the soluble ball 14 Dissolution is carried out under the action of formation fluid.

Specifically, according to the specific structure and form of the above-mentioned bridge plug, the specific process and function of the setting method of the bridge plug are as follows:

The throwing nail 13 is screwed into the toe cap 12 and screwed into the corresponding hole in the tie rod 16 of the setting tool, and the pushing cylinder 15 of the setting tool is aligned with the bridge plug to push the end surface of the cylinder 15 In contact with the end surface of the upper joint 1, the position of the toe cap 12 and the center tube 7 is fixed by the tie rod 16 to achieve connection with the setting tool.

Place the bridge plug in the sleeve at the predetermined position, with the end of the bridge plug with the toe cap 12 facing To the inside of the setting position.

When the pusher 15 of the setting tool is actuated, the shoe head 12 and the center rod 7 of the bridge plug are fixed by the hand shearing nail 13; the end face of the joint 1 is pressed, the pressing force is cut to cut the nail 12, and the pushing cylinder 15 continues to be squeezed. The joint 1 is pressed, and the upper joint 1 drives the inverted ring gear 3 to move downward, and the end ring 4, the wristband 8, the sub-cartridge 5, the main rubber cylinder 6, and the slip seat 9 are successively pressed.

The main rubber tube 6 and the sub-cylinder 5 are radially expanded after being squeezed, and are closely attached to the inner wall of the sleeve, and the bridge plug is closed. After the kava seat 9 is subjected to the downward pressing force, the slip bearing nail 10 is cut, and then the slip 11 is pressed, and the slip 11 is crushed and then cracked, embedded in the sleeve, and anchored to the bridge plug. At the same time, the downward pressing force of the push cylinder 15 is transmitted to the throwing nail 13 in the shoe head 12. After the main rubber tube 6 and the slip 11 are completely set, the throwing nail 13 is pulled off by the setting tool tie rod 16 to realize the separation of the setting tool from the bridge plug.

After the bridge plug is seated, the setting tool is proposed to put a dissolvable ball 14 into the well, and the dissolving ball 14 sits in the ball seat at the upper end of the center rod 7 and begins to fracturing.

After the completion of the fracturing, the dissolvable ball 14 dissolves under the action of the fracturing backflow liquid for a certain period of time, leaving the inner diameter of the center rod 7 as a production passage.

In the present invention, a metal center tube is used as the center tube 7 of the bridge plug. Due to the high strength of the metal material, the center tube 7 can be a central tube 7 having a thinner tube wall and a larger inner diameter, and the strength of the center tube 7 can still be ensured. During the setting process, the central tube 7 has high strength and the setting process is simple and safe. In the subsequent use, since the inner diameter of the metal tube 7 is large, the oil and gas transmission between the oil layers can be satisfied, and the drilling step is avoided. The difficulties brought.

The above is a detailed description of a large-diameter bridge plug and its setting method provided by the present invention. The principles and embodiments of the present invention have been described herein with reference to specific examples, and the description of the above embodiments is only to assist in understanding the method of the present invention and its core idea. It should be noted that those skilled in the art can make various modifications and changes to the present invention without departing from the spirit and scope of the invention.

Claims

A large-diameter bridge plug, characterized by comprising an upper joint (1), a central tube (7), a leading shoe (12) and a bridge plug assembly;

The upper joint (1) is a ring member, and is fixedly sleeved on an outer side of one end of the center tube (7);

The central tube (7) is a metal center tube, and a center of the center tube (7) near the upper joint (1) is provided with a soluble ball seat, and the center tube (7) is a drillable metal piece;

The shoe head (12) is a ring member fixedly sleeved on the outer side of the other end of the center tube (7), and the shoe head (12) is provided with a tie rod for being fitted in the bridge plug ( 16) a fixedly connected device;

The bridge plug assembly is sleeved on the outside of the middle section of the center tube (7) and is located between the upper joint (1) and the leader (12).
The large-diameter bridge plug according to claim 1, wherein the bridge plug assembly comprises an end ring (4), a wristband (8), a slip (11), a slip seat (9) and a rubber cylinder , each of which is sleeved on the outer side of the central tube (7); one of the wrist ends (8) is disposed on each of the tapered end faces of the rubber cylinder; the wristband (8) is a sleeve with a taper The tapered end surface of the wristband (8) is attached to the tapered end surface of the rubber cylinder, and the wristband (8) is a plastic wristband; the outer sides of the tapered end faces of the two wristbands (8) One end ring (4) is sleeved respectively, wherein the other end of one of the end rings (4) is fitted to the tapered end surface of the upper joint (1), and the other end of the end ring (4) is another One end is fitted to the tapered end surface of the slip seat (9), and the slip seat (9) is connected with the center tube (7) through a slip holder (10); the slip seat ( The other end face of 9) is fitted to the tapered end surface of the slip (11), and one end of the non-conical surface of the slip (11) is in contact with one end of the lead shoe (12).
The large-diameter bridge plug according to claim 2, wherein the rubber cylinder comprises a main rubber cylinder (6) and a secondary rubber cylinder (5); the main rubber cylinder (6) and the secondary rubber cylinder ( 5) is sleeved on the outer side of the central tube (7), the secondary rubber tube (5) is a tapered sleeve, and the tapered inner side wall of the secondary rubber tube (5) is attached to the main On the outer side wall of the lower end port of the rubber cylinder (6), the tapered outer wall of the sub-cylinder (5) is fitted on the tapered end surface of the wrist guard (8).
The large-diameter bridge plug according to claim 3, further comprising an inverted toothed ring (3) sleeved on the inner wall of the upper joint (1) and the center tube ( 7) between the outer walls, the inner zigzag thread on the inner wall of the upper joint (1) and the outer serrated thread of the inverted tooth ring (3) The inner serration thread of the inverted ring (3) is threaded with the outer serration of the central tube (7).
The large-diameter bridge plug according to claim 4, wherein the secondary rubber cylinder (5) is disposed on both end faces of the main rubber cylinder (6), and the secondary rubber cylinder (5) The number is at least two.
The large-diameter bridge plug according to claim 5, wherein the upper joint (1) is fixed to the center tube (7) by an upper joint shearing pin (2), and the upper joint shearing nail (2) Arranged in the radial direction of the central tube (7), the upper end of the upper joint (1) is provided with a claw structure for connecting other bridge plug lower joints, and the lead-in toe (12) is cut by hand ( 13) fixed to the pull rod (16).
The large-diameter bridge plug according to claim 6, characterized in that the upper joint (1), the end ring (4), the slip seat (9), the slip (11) and the The toe caps (12) are all drillable metal parts.
The large-diameter bridge plug according to claim 7, wherein the slip (11) is an integral slip, and an outer surface of the slip is provided with a uniformly distributed stress concentration groove, and the direction of the stress concentration groove The axial direction of the slip (11), the end surface of the slip (11) contacting the booting head (12) is provided with a radial opening groove; the slip (11) is inserted into the boot shoe A slot in one end of the head (12) is coupled to the lead shoe (12).
A large-diameter bridge plug setting method for plugging oil and gas wells, characterized in that the method comprises:

Fixing the pull rod (16) of the setting tool with the lead shoe (12), aligning the push tube (15) in the setting tool with the bridge plug, the end surface thereof and the upper portion of the bridge plug The joint (1) is in contact with each other, and the position of the shoe head (12) and the center tube (7) is fixed by the pull rod (16) to realize the connection of the tie rod (16) with the bridge plug;

Lowering the bridge plug to a predetermined position in the casing by a cable or coiled tubing;

Actuating the setting tool, the pushing cylinder (15) pressing the end face of the upper joint (1), the upper joint (1) pressing the bridge plug assembly, sealing the bridge plug and the An annular space of the sleeve and anchoring the bridge plug, disconnecting the fixed connection of the tie rod (16) with the lead shoe (12) to separate the setting tool from the bridge plug;

Lifting the setting tool separated from the bridge plug to the ground, placing the soluble ball (14) onto the soluble ball seat at one end of the upper joint (1), completing the setting, and performing fracturing construction; Crack construction Thereafter, the soluble spheres (14) are dissolved by the formation fluid.