Integrated expansion packer capable of preventing midway setting

Abstract

The utility model belongs to the technical field of oil extraction of oil and gas fields, and particularly relates to an integrated expansion packer capable of preventing midway setting, which comprises a body structure and a sliding sleeve structure, the body structure comprises an upper joint, an injection body, an expansion sealing structure and a lower joint, and the expansion sealing structure comprises a sealing rubber sleeve, a mandrel and a liquid inlet channel; the sliding sleeve structure comprises an inner sliding sleeve installed in the body structure in a sliding mode and a starting steel ball thrown in the inner sliding sleeve, the inner sliding sleeve and the upper connector are mutually fixed through a starting pin, a liquid inlet of the liquid inlet channel can be sealed, and the inner sliding sleeve, the injection body and the mandrel are mutually sealed through first sealing rings. After the sliding sleeve structure moves downwards through pressurization, the liquid inlet of the liquid inlet channel is opened, and the sealing rubber barrel expands under pressurization. The body structure of the packer adopts a high-strength framework, so that the packer is high in pressure bearing capacity, reliable in performance, large in expansion ratio of the sealing rubber sleeve, long in sealing surface of the rubber sleeve, good in packing effect, good in adaptability to well diameters, compact in overall structure, short and small, and convenient to construct.

Description

Technical Field

[0001] The utility model belongs to the technical fields of oil and gas field oil production, gas production, well completion stimulation and workover, and particularly relates to an integrated expansion packer for preventing premature setting. Background Art

[0002] An expansion packer is an expansion type fracturing packer with an expandable rubber cylinder as a sealing element and using hydraulic pressure difference for setting, which is specifically used for interlayer sealing in staged fracturing or construction such as sandblasting perforation. It is matched with corresponding downhole tools to form a staged fracturing construction technology string to complete the operations of dragging and multi-stage layered fracturing. However, the existing expansion packers often have defects such as large structural volume, easy premature setting, and poor sealing effect. Based on the above problems, it is of great practical significance to design an integrated expansion packer for preventing premature setting with a compact and short overall structure, convenient for construction and easy control of setting and releasing. Summary of the Utility Model

[0003] The utility model provides an integrated expansion packer for preventing premature setting to solve the above problems existing in the prior art.

[0004] The technical solution adopted by the utility model to solve this problem is as follows:

[0005] An integrated expansion packer for preventing premature setting, comprising:

[0006] A body structure, which includes an upper joint, a jet body, an expansion sealing structure and a lower joint connected in sequence, and the expansion sealing structure includes a sealing rubber cylinder, a mandrel arranged inside the sealing rubber cylinder, and a liquid inlet channel formed between the two;

[0007] A sliding sleeve structure, which includes an inner sliding sleeve slidably inserted into the body structure and a starting steel ball placed inside the head end of the inner sliding sleeve to close the inner sliding sleeve. The head side of the inner sliding sleeve is fixedly connected to the upper joint through a starting pin, and the tail side can close the liquid inlet of the liquid inlet channel. The inner sliding sleeve is respectively sealed with the jet body and the mandrel through a first sealing ring;

[0008] When the sliding sleeve structure descends under pressure, the liquid inlet of the liquid inlet channel is opened, and the sealing rubber cylinder expands under pressure.

[0009] In the above technical solution, the upper joint, the jet body, the mandrel and the lower joint are arranged in sequence along the head and tail extension direction of the body structure and are internally through.

[0010] In the above technical solution, the head end of the upper joint is embedded and engaged with the jet body, and the two are sealed with each other through a second sealing ring.

[0011] In the above technical solution, a backstop platform for preventing the inner sliding sleeve from moving upward is provided on the inner wall of the upper joint.

[0012] In the above technical solution, a sealing bevel is provided on the inner wall at the head end of the inner sliding sleeve.

[0013] In the above technical solution, a positioning sleeve is provided on the outside of the injection body, and the positioning sleeve is fixed to the injection body through a fixing key.

[0014] In the above technical solution, the injection body is respectively embedded and engaged with the mandrel and the sealing rubber barrel. The inner diameter sizes of the injection body and the mandrel are the same. An inlet of the liquid inlet channel is formed between the injection body and the mandrel, and the inlet is communicated with the liquid inlet channel between the mandrel and the sealing rubber barrel.

[0015] In the above technical solution, the sealing rubber barrel is sleeved on the outside of the mandrel, and the head and tail ends of the mandrel respectively extend out of the sealing rubber barrel.

[0016] In the above technical solution, when the inner sliding sleeve moves downward and cooperates with the mandrel to form a downward sealing structure, the downward sealing structure includes:

[0017] A sliding sleeve sealing bevel, which is formed on the outer wall at the tail end of the inner sliding sleeve;

[0018] A mandrel sealing bevel, which is formed on the inner wall at the tail side of the mandrel and is used to receive and seal the inner sliding sleeve. When the inner sliding sleeve moves downward, the sliding sleeve sealing bevel and the mandrel sealing bevel are closely attached.

[0019] In the above technical solution, a floating joint is further sleeved on one side of the sealing rubber barrel close to the lower joint. The lower joint is respectively embedded and engaged with the mandrel and the floating joint. The lower joint and the mandrel are sealed with each other through a third sealing ring, and the lower joint and the floating joint are sealed with each other through a fourth sealing ring.

[0020] The advantages and positive effects of the present utility model are:

[0021] 1. In the present utility model, the body structure of the packer adopts a high-strength skeleton, has high pressure resistance and reliable performance. Among them, the sealing rubber barrel has a large expansion ratio, a long sealing surface of the rubber barrel, good sealing effect, good adaptability to the well diameter, and the overall structure of the packer is compact and short, which is convenient for construction.

[0022] 2. In the present utility model, when the sliding sleeve structure moves downward under pressure, the inlet of the liquid inlet channel is opened, and the sealing rubber barrel expands under hydraulic pressure. Hydraulic setting is adopted, and the pipe string is depressurized to release the seal. The control is convenient, and it can be repeatedly expanded and released.

[0023] 3. In the present utility model, the liquid inlet passage adopts a slotted structure to prevent fracturing sand and other impurities from entering the sealing rubber barrel during the setting and construction of the packer, damaging the sealing rubber barrel, and improving the service life and safety of the rubber barrel.

[0024] 4. In the present utility model, a limit key is installed inside the floating joint of the packer, and the lower joint has a keyway. When the setting size of the packer reaches the designed outer diameter, the floating joint stops moving, avoiding excessive stress on the sealing rubber barrel and damage, and realizing the limitation of the setting stroke of the rubber barrel. Brief Description of the Drawings

[0025] The technical solution of the present utility model will be further described in detail below in conjunction with the drawings and embodiments. However, it should be noted that these drawings are only designed for explanatory purposes and therefore do not limit the scope of the present utility model. In addition, unless otherwise specified, these drawings are only intended to conceptually illustrate the structural configurations described herein and are not necessarily drawn to scale.

[0026] Figure 1 is a half-sectional structural schematic diagram of Embodiment 1;

[0027] Figure 2 is Figure 1 the enlarged schematic diagram of Part A in

[0028] Figure 3 is a half-sectional structural schematic diagram of the body structure in Embodiment 1;

[0029] Figure 4 is a sectional structural schematic diagram of the sliding sleeve structure;

[0030] Figure 5 is a half-sectional structural schematic diagram of Embodiment 2.

[0031] In the figures: 1 - upper joint, 2 - jet body, 3 - positioning sleeve, 4 - starting steel ball, 5 - starting pin, 6 - inner sliding sleeve, 7 - mandrel, 8 - floating joint, 9 - lower joint, 10 - sealing rubber barrel, 11 - second sealing ring, 12 - first sealing ring, 13 - third sealing ring, 14 - fourth sealing ring, 15 - limit key, 16 - anti-backflow platform, 17 - fixed key, 18 - sealing inclined surface, 19 - liquid inlet, 20 - sliding sleeve sealing inclined surface, 21 - mandrel sealing inclined surface. Detailed Embodiment

[0032] First of all, it should be noted that the following will specifically illustrate the specific structure, characteristics, advantages, etc. of the present utility model by way of examples. However, all descriptions are only for illustration purposes and should not be construed as forming any limitation to the present utility model. In addition, any single technical feature described or implied in each of the embodiments mentioned herein, or any single technical feature shown or implied in each of the drawings, can still be arbitrarily combined or deleted between these technical features (or their equivalents), so as to obtain more other embodiments of the present utility model that may not be directly mentioned herein. Additionally, for the sake of simplifying the drawings, the same or similar technical features may only be marked at one place in the same drawing.

[0033] In the present utility model, unless otherwise clearly defined and limited, terms such as "installation", "setting", "connection", "fixation", "swivel connection", etc. shall be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements or the interaction relationship between two elements. Unless otherwise clearly defined, for those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances. The present utility model will be specifically described below with reference to the drawings. Embodiment 1

[0034] An integrated expansion packer for preventing premature setting, comprising a body structure and a sliding sleeve structure, wherein:

[0035] The body structure includes an upper joint 1, a jet body 2, an expansion sealing structure, and a lower joint 9 connected in sequence. The expansion sealing structure includes a sealing rubber cylinder 10, a mandrel 7 disposed inside the sealing rubber cylinder 10, and a liquid inlet channel formed therebetween.

[0036] The sliding sleeve structure includes an inner sliding sleeve 6 slidably inserted into the body structure and a starting steel ball 4 placed within the head end of the inner sliding sleeve 6 for closing the inner sliding sleeve 6. The head side of the inner sliding sleeve 6 is fixed to the upper joint 1 through a starting pin 5, and the tail side can close the liquid inlet of the liquid inlet channel. The inner sliding sleeve 6 is respectively sealed with the jet body 2 and the mandrel 7 through a first sealing ring 12.

[0037] When the sliding sleeve structure descends under pressure, the liquid inlet of the liquid inlet channel is opened, and the sealing rubber cylinder 10 expands under pressure.

[0038] In this embodiment, the main body structure adopts a high-strength skeleton with high pressure bearing and reliable performance. The sealing rubber tube has a large expansion ratio, a long sealing surface, a good sealing effect, and good adaptability to the well diameter. The injection body and the sliding sleeve structure form a spray gun, which tightly combines the spray gun and the packer into one, and the structure is more compact and short, which is convenient for construction.

[0039] Before the ball is dropped and the pressure is applied, the liquid inlet channel of the sealing rubber tube is kept closed under the action of the inner sleeve, so that the liquid cannot enter the inner cavity of the packer. The liquid inlet channel can be opened only after the protective sleeve, that is, the inner sleeve, is removed. That is, when the sleeve structure is pressurized and moved downward, the liquid inlet of the liquid inlet channel is opened, and the sealing rubber tube 10 expands and swells under hydraulic pressure, adopts hydraulic setting, and the pipe column is depressurized and unsealed, which is easy to control and can be repeatedly expanded and unsealed. As the construction pressure in the oil pipe increases, the sealing rubber tube fits more closely with the well wall, and the pressure difference bearing effect is better. The rubber of the sealing rubber tube used above is processed by a unique process, and the high-temperature sealing is reliable.

[0040] Furthermore, in this embodiment, it can also be considered that the upper joint 1, the injection body 2, the core shaft 7 and the lower joint 9 are arranged in sequence along the head and tail extension direction of the body structure and are internally connected.

[0041] Furthermore, in this embodiment, it can also be considered that the upper joint 1 and the head end of the injection body 2 are embedded in and engaged with each other, and the two are sealed with each other through a second sealing ring 11.

[0042] Furthermore, in this embodiment, it can also be considered that the inner wall of the upper joint 1 is provided with a non-return platform 16 for preventing the inner sliding sleeve 6 from moving upward, so that the inner sliding sleeve can only move in one direction.

[0043] Furthermore, in this embodiment, it can also be considered that a sealing slope 18 is provided on the inner wall of the head end of the inner sleeve 6, and when the ball is thrown, the starting steel ball cooperates with the sealing slope to achieve the sealing of the inner sleeve.

[0044] Furthermore, in the present embodiment, a positioning sleeve 3 is provided on the outside of the injection body 2, and the positioning sleeve 3 is fixed to the injection body 2 by a fixing key 17. The injection body is protected by cemented carbide to prevent damage to the body caused by splashing back of fracturing sand during injection. At the same time, the design of the positioning sleeve enables the inner sliding sleeve to precisely match the nozzle.

[0045] Furthermore, it can also be considered in this embodiment that the injection body 2 is respectively embedded and engaged with the mandrel 7 and the sealant cartridge 10. The inner diameter dimensions of the injection body 2 and the mandrel 7 are the same. An inlet 19 of the liquid inlet passage is formed between the injection body 2 and the mandrel 7. The inlet 19 is communicated with the liquid inlet passage between the mandrel 7 and the sealant cartridge 10. The liquid can be conveyed to the liquid inlet passage of the sealant cartridge through the liquid inlet passage between the mandrel and the sealant cartridge, thereby realizing the swelling of the sealant cartridge.

[0046] Furthermore, it can also be considered in this embodiment that the liquid inlet passage adopts a slotted structure to prevent proppant and other impurities from entering the sealant cartridge during the setting and construction of the packer, damaging the sealant cartridge, and improving the service life and safety of the cartridge.

[0047] Furthermore, it can also be considered in this embodiment that the sealant cartridge 10 is sleeved outside the mandrel 7, and both the head and tail ends of the mandrel 7 extend beyond the sealant cartridge 10.

[0048] Furthermore, it can also be considered in this embodiment that when the inner sliding sleeve 6 moves downward and cooperates with the mandrel 7 to form a downward sealing structure, the downward sealing structure includes:

[0049] A sliding sleeve sealing inclined surface 20, which is formed on the outer wall of the tail end of the inner sliding sleeve 6;

[0050] A mandrel sealing inclined surface 21, which is formed on the inner wall of the tail side of the mandrel 7 and is used to receive and seal the inner sliding sleeve 6. When the inner sliding sleeve 6 moves downward, the sliding sleeve sealing inclined surface 20 is closely attached to the mandrel sealing inclined surface 21, which on the one hand prevents the inner sliding sleeve from continuing to move downward, and on the other hand plays a sealing role.

[0051] Furthermore, it can also be considered in this embodiment that a floating joint 8 is also sleeved on one side of the sealant cartridge 10 close to the lower joint 9. The lower joint 9 is respectively embedded and engaged with the mandrel 7 and the floating joint 8. The lower joint 9 and the mandrel 7 are sealed with each other through a third sealing ring 13, and the lower joint 9 and the floating joint 8 are sealed with each other through a fourth sealing ring 14. Embodiment 2

[0052] Embodiment 2 of the present utility model is further improved on the basis of Embodiment 1 in order to fully exert the technical advantages of the present invention. The following is an illustrative description of this.

[0053] For example: A limit key 15 is also provided between the lower joint 9 and the floating joint 8. A limit key is installed inside the floating joint of the packer, and the lower joint has a keyway. When the setting size of the packer reaches the designed outer diameter, the floating joint no longer moves, avoiding excessive force on the sealant cartridge and damage, and realizing the limitation of the setting stroke of the cartridge.

[0054] Working principle: The packer is lowered into the downhole construction position along with the work string. The corresponding starting steel ball is dropped. After the starting steel ball reaches the position, liquid (fracturing fluid, acid fluid or clear water) is pumped into the tubing. When the pressure reaches the designed pressure, the shear pin is sheared off, and the inner sliding sleeve moves downward and seats on the sealing inclined surface at the lower part of the packer mandrel. At this time, the liquid inlet channel of the sealing rubber barrel is opened, and the sealing rubber barrel expands under the action of hydraulic pressure and contacts the casing wall or the open-hole rock. As the pressure increases, the purpose of sealing the upper and lower parts of the wellbore is achieved. At the same time, the injection hole liquid is opened, and the fracturing fluid and proppant are sprayed from the cemented carbide nozzle to shoot open the casing and the formation. After the construction is completed, the tubing string is depressurized after the pump is stopped, and the packer is automatically released.

[0055] The above embodiments have described the present invention in detail, but the described content is only the preferred embodiment of the present invention and cannot be considered as limiting the scope of implementation of the present invention. Any equivalent changes and improvements made within the scope of the application of the present invention shall still fall within the scope covered by the patent of the present invention.

Claims

1. An integrated expansion packer for preventing mid-course setting, characterized in that: include: The body structure comprises an upper joint, a spray body, an expansion sealing structure and a lower joint which are connected in sequence, wherein the expansion sealing structure comprises a sealing rubber tube, a core shaft arranged inside the sealing rubber tube and a liquid inlet channel formed therebetween; The sliding sleeve structure includes an inner sliding sleeve slidably inserted into the body structure and a starting steel ball put into the head end of the inner sliding sleeve for sealing the inner sliding sleeve. The head side of the inner sliding sleeve is fixed to the upper joint by a starting pin, and the tail side can seal the liquid inlet of the liquid inlet channel. The inner sliding sleeve is sealed with the injection body and the core shaft respectively by a first sealing ring; When the sliding sleeve structure moves downward under pressure, the liquid inlet of the liquid inlet channel is opened, and the sealing rubber cylinder expands under pressure.

2. The integrated expansion packer for preventing mid-course setting according to claim 1, characterized in that: The upper joint, the injection body, the core shaft and the lower joint are arranged in sequence along the head and tail extension direction of the body structure and are connected internally.

3. The integrated expansion packer for preventing mid-course setting according to claim 1, characterized in that: The upper joint and the head end of the spray body are embedded in and engaged with each other, and are sealed with each other through a second sealing ring.

4. The integrated expansion packer for preventing mid-course setting according to claim 1, characterized in that: The inner wall of the upper joint is provided with a non-return platform for preventing the inner sliding sleeve from moving upward.

5. The integrated expansion packer for preventing mid-course setting according to claim 1, characterized in that: A sealing slope is arranged on the inner wall of the head end of the inner sliding sleeve.

6. The integrated expansion packer for preventing mid-course setting according to claim 1, characterized in that: A positioning sleeve is arranged on the outer side of the injection body, and the positioning sleeve is fixed to the injection body through a fixing key.

7. The integrated expansion packer for preventing mid-course setting according to claim 1, characterized in that: The injection body, the core shaft and the sealing rubber tube are respectively embedded and engaged with each other. The injection body and the core shaft have the same inner diameter. A liquid inlet of the liquid inlet channel is formed between the injection body and the core shaft. The liquid inlet is connected to the liquid inlet channel between the core shaft and the sealing rubber tube.

8. The integrated expansion packer for preventing mid-course setting according to claim 7, characterized in that: The sealing rubber tube is sleeved on the outer side of the core shaft, and the head and tail ends of the core shaft extend out of the sealing rubber tube respectively.

9. The integrated expansion packer for preventing mid-course setting according to claim 1, characterized in that: When the inner sleeve moves downward, it cooperates with the core shaft to form a downward sealing structure, and the downward sealing structure includes: A sleeve sealing bevel, which is formed on the outer wall of the rear end of the inner sleeve; The core shaft sealing bevel is formed on the inner wall of the rear side of the core shaft and is used to receive and seal the inner sleeve. When the inner sleeve moves downward, the sleeve sealing bevel fits tightly with the core shaft sealing bevel.

10. The integrated expandable packer for preventing mid-course setting according to claim 1, characterized in that: A floating joint is also mounted on one side of the sealing rubber cylinder close to the lower joint. The lower joint, the core shaft and the floating joint are respectively embedded and engaged with each other. The lower joint and the core shaft are sealed with a third sealing ring, and the lower joint and the floating joint are sealed with a fourth sealing ring.

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