CN112412387B - Reusable gas drilling two-plugging one-injection integrated hydraulic packer - Google Patents

Reusable gas drilling two-plugging one-injection integrated hydraulic packer Download PDF

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Publication number
CN112412387B
CN112412387B CN202011318644.7A CN202011318644A CN112412387B CN 112412387 B CN112412387 B CN 112412387B CN 202011318644 A CN202011318644 A CN 202011318644A CN 112412387 B CN112412387 B CN 112412387B
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pipe
sealing
water injection
gas drilling
injection pipe
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CN202011318644.7A
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CN112412387A (en
Inventor
程健维
王钰
吴宇辰
吴雨航
梅境
田松杰
罗望
关品品
郑欣睿
张蕊
王最
宋宛亭
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Hainan Chaowen Qixue Intellectual Property Co ltd
Shandong Jinfengyuan Technical Service Co ltd
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China University of Mining and Technology CUMT
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    • EFIXED CONSTRUCTIONS
    • E21EARTH OR ROCK DRILLING; MINING
    • E21BEARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B33/00Sealing or packing boreholes or wells
    • E21B33/10Sealing or packing boreholes or wells in the borehole
    • E21B33/12Packers; Plugs
    • E21B33/126Packers; Plugs with fluid-pressure-operated elastic cup or skirt
    • EFIXED CONSTRUCTIONS
    • E21EARTH OR ROCK DRILLING; MINING
    • E21BEARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B33/00Sealing or packing boreholes or wells
    • E21B33/10Sealing or packing boreholes or wells in the borehole
    • E21B33/13Methods or devices for cementing, for plugging holes, crevices or the like

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  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Geology (AREA)
  • Mining & Mineral Resources (AREA)
  • Physics & Mathematics (AREA)
  • Environmental & Geological Engineering (AREA)
  • Fluid Mechanics (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Pipe Accessories (AREA)

Abstract

The invention discloses a reusable two-plug one-injection integrated hydraulic packer for gas drilling, which comprises a hard support rod sleeved outside a gas pipe, wherein the tail end of the hard support rod is sleeved with a sealing bag, a water injection pipe and an injection pipe are arranged in the hard support rod, the tail end of the injection pipe is communicated with an inner cavity of the gas drilling through a non-coagulating slurry injection port, the tail end of the water injection pipe is communicated with the sealing bag through a liquid inlet of a bag at the bottom of a hole, the front end of the hard support rod is sleeved with a plurality of sealing rubbers, two sides of each sealing rubber are correspondingly provided with annular bodies, the two annular bodies at the outermost side are connected with a hydraulic cylinder, a system limiting valve for plugging the water injection pipe is arranged on the water injection pipe, a reset spring is correspondingly arranged inside each sealing rubber, double sealing can be realized, the sealing effect is better, and the packer can be used repeatedly after pressure relief, solves the problems of insufficient expansion and difficult recovery of the original capsular bag.

Description

Reusable gas drilling two-plugging one-injection integrated hydraulic packer
Technical Field
The invention relates to gas extraction drilling hole plugging equipment, in particular to a reusable gas drilling hole two-plugging one-injection integrated hydraulic packer.
Background
The traditional hole sealing method adopts a gas sealing concept, namely gas is sealed by solid, so that the problem of plugging of a new crack is difficult to solve, and the problem that the new crack is difficult to plug in the gas extraction process is effectively solved by using non-solidified green slurry of the gas sealing concept to realize dynamic plugging of the gas extraction drill crack, so that the gas extraction effect can be obviously improved. However, the new plugging method has the problems of imperfect plugging system and lack of matched equipment and experience in use. The existing widely applied 'two-plug one-injection' equipment has the defects of high failure rate and no reusability; although reusable hole sealing equipment is developed, a simple water injection expansion bag method is mostly used, and the problems of insufficient expansion and difficult recovery exist in practical application.
Disclosure of Invention
Aiming at the technical defects, the invention aims to provide a reusable gas drilling two-plugging one-injection integrated hydraulic packer.
In order to solve the technical problems, the invention adopts the following technical scheme:
the invention provides a reusable two-plug one-injection integrated hydraulic packer for gas drilling, which comprises a hard support rod sleeved outside a gas pipe, wherein a sealing bag is sleeved at the tail end of the hard support rod, hard plugs sleeved outside the hard support rod and the gas pipe and used for axially fixing the sealing bag are arranged at two ends of the sealing bag, a water injection pipe and a grouting pipe are arranged in the hard support rod, the tail end of the grouting pipe is communicated with an inner cavity of the gas drilling through a non-setting slurry grouting port, the tail end of the water injection pipe is communicated with the sealing bag through a liquid inlet of a bag at the bottom of a hole, a plurality of sealing rubbers are sleeved at the front end of the hard support rod, annular bodies are correspondingly arranged at two sides of each sealing rubber, the two annular bodies at the outermost side are connected with a hydraulic cylinder, the liquid inlet of the hydraulic cylinder is communicated with the water injection pipe, and a system limiting valve used for plugging the water injection pipe is arranged on the water injection pipe, and a return spring is correspondingly arranged in the sealing rubber.
Preferably, the end of the gas pipe is formed with a perforated pipe for better gas collection.
Preferably, the tip of water injection pipe is formed with the water filling port, the limit valve of system is close to water filling port end setting, through the water filling port to the water injection pipe water injection, and the shutoff water injection pipe that the limit valve of system can be better in order to realize the seat of equipment to seal in the feeder, and can carry out the pressure release when the deblocking.
Preferably, the tip of slip casting pipe is provided with the tee bend, the front end of the straight tube section of tee bend and the slip casting pipe intercommunication of front side, the rear end of straight tube section and the slip casting pipe intercommunication of rear side, the slip casting pipe tip of front side is formed with the slip casting mouth, tee bend top tube section intercommunication has the manometer, and the manometer that sets up that tee bend structure can be better, through the observation slip casting pressure that the manometer can be better, the slip casting mouth adopts the screw plug sealed, closes when not needing the slip casting, when needing the slip casting, opens the end cap, utilize automatic slip casting to mend the thick liquid equipment injection thick liquid can.
Preferably, the return spring is arranged axially, and the sealing rubber is rebounded to the original position through the return spring.
Preferably, the hydraulic cylinders are arranged oppositely and used for extruding the sealing rubber, so that the sealing rubber is conveniently extruded and expanded to be sealed.
Preferably, the head-on of the system limiting valve is of a slope type, the system limiting valve can be opened by adopting a slender rod-shaped object, and pressure relief is easy to carry out for reuse after extraction is completed.
The invention has the beneficial effects that: the invention has simple structure, can realize double sealing, has better sealing effect, can be repeatedly used after pressure relief, solves the problems of insufficient expansion of the original bag and difficult recovery, is a brand new exploration for reusable equipment in the system, and when in specific use, the integrated sealing bag is put at a proper position of a drill hole to connect high-pressure water to a water filling port, the water firstly expands the sealing bag through a liquid inlet of the bag at the bottom of the hole to finish the prior plugging of the bag at the bottom, and the water pressure does not reach the working water pressure of a hydraulic sealing mechanism at the port; through the change of the liquid pressure in the device, after the bottom bag completes the fixed and stable primary plugging, immediately the water pressure in the device gradually increases to the movement water pressure threshold of the orifice hydraulic sealing mechanism, the piston of the hydraulic cylinder (6) is pushed, meanwhile, the sealing rubber (7) is bidirectionally extruded until the sealing rubber (7) expands and is tightly clamped on the hole wall of the gas drilling hole, and the second re-plugging is started; through the change of the liquid pressure in the device, after the plugging is initially finished, the water pressure is gradually increased, finally, the limiting valve of the system is pushed under the action of the water pressure to plug the water injection pipe, the plugging process is finished, the prepared non-setting slurry is injected through a slurry injection port during the slurry injection, after the proper pressure is reached, the tee joint is screwed down, the slurry injection work is finished, and the slurry is supplemented by using automatic slurry injection and supplement equipment when the slurry is required to be supplemented; during the deblocking, the use instrument is artifical with the spacing valve of system and is recovered, and the pressure release drains, and the inside reset spring effect of sealing rubber (7) makes sealing rubber (7) kick-back to original position, extracts the bag at last and can carry out next hole sealing operation.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
FIG. 1 is a schematic view of the overall structure of the present invention;
FIG. 2 is a schematic structural view of a setting mechanism of the present invention;
FIG. 3 is a schematic view of the setting state of the present invention;
FIG. 4 is a schematic structural view of a setting mechanism in a setting state according to the present invention;
FIG. 5 is a schematic representation of the relationship of expansion volume and engagement force of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The embodiment provides a reusable two-plug one-injection integrated hydraulic packer for gas drilling, which comprises a hard support rod sleeved outside a gas pipe 1, wherein a sealing bag 11 is sleeved at the tail end of the hard support rod, hard plugs 12 sleeved outside the hard support rod and the gas pipe 1 and used for axially fixing the sealing bag 11 are arranged at two ends of the sealing bag 11, a water injection pipe and a grouting pipe are arranged in the hard support rod, the tail end of the grouting pipe is communicated with an inner cavity of the gas drilling through a non-coagulating slurry grouting port 9, the tail end of the water injection pipe is communicated with the sealing bag 11 through a hole bottom bag liquid inlet 10, a plurality of sealing rubbers 7 are sleeved at the front end of the hard support rod, annular bodies are correspondingly arranged on two sides of each sealing rubber 7, two outermost sides of each sealing rubber 7 are connected with an annular body 6, and a liquid inlet of each hydraulic cylinder 6 is communicated with the water injection pipe, be provided with the system limiting valve 5 that is used for the shutoff water injection pipe on the water injection pipe, the inside correspondence of sealing rubber 7 is provided with reset spring 8, the tip of slip casting pipe is provided with tee bend 4. The tail end of the gas pipe 1 is provided with a perforated pipe 13, so that gas can be collected better. The tip of water injection pipe is formed with water filling port 2, system limit valve 5 is close to 2 end settings of water filling port, through 2 water injection to the water injection pipe water injection of water filling port, and the seat that pressure in order to realize equipment in the donator seals, shutoff water injection pipe that system limit valve 5 can be better, and can carry out the pressure release when the deblocking. The tip of slip casting pipe is provided with tee bend 4, the front end of tee bend 4 straight tube section and the slip casting pipe intercommunication of front side, the rear end of straight tube section and the slip casting pipe intercommunication of rear side, the slip casting pipe tip of front side is formed with slip casting mouth 3, tee bend 4's last tube section intercommunication has the manometer, and tee bend structure's setting can be better sets up the manometer, through the observation slip casting pressure that the manometer can be better, and slip casting mouth 3 adopts the screw plug sealed, closes when not needing the slip casting, when needing the slip casting, opens the end cap, and it can to utilize automatic slip casting to mend the thick liquid injection of thick liquid equipment. The reset spring 8 is arranged in the axial direction, and after pressure relief is carried out, the sealing rubber 7 is rebounded to the original position through the reset spring. The hydraulic cylinder 6 is arranged in opposite direction and used for extruding the sealing rubber 7, so that the sealing rubber 7 is conveniently extruded, and the sealing rubber 7 is expanded to be sealed. The head-on of the system limiting valve 5 is in a slope type, the system limiting valve 5 can be opened by adopting a slender rod-shaped object, and pressure relief is easy to carry out and reuse after extraction is finished.
When the device is used, as shown in figure 1, after the gas drilling hole is formed, the integrated sealing bag is put to a proper drilling position according to the original process, high-pressure water is connected to the water injection port 2, the water firstly expands the sealing bag 11 through the liquid inlet 10 of the bag at the bottom of the hole to complete the advanced plugging of the bag at the bottom, and the water pressure does not reach the working water pressure of the hole opening setting mechanism; as shown in fig. 2 and 4, the water pressure in the device is gradually increased, and then the water pressure in the device is gradually increased to the movement water pressure threshold of the orifice hydraulic sealing mechanism, the piston of the hydraulic cylinder 6 is pushed, and meanwhile, the sealing rubber 7 is bidirectionally extruded until the sealing rubber 7 is expanded and tightly clamped on the hole wall of the gas drilling hole, and the second re-plugging is opened; finally, pushing a system limiting valve 5 to plug the water injection pipe under the action of water pressure to finish the plugging process; as shown in fig. 3 and 4, during grouting, the prepared non-setting slurry is injected through the grouting port 3, discharged into a cavity between the equipment and the inner wall of the gas drill hole from the non-setting slurry grouting port, and the grouting pressure is observed on the tee joint 4, and when the proper pressure is reached, the plug on the tee joint 4 is closed, so that the grouting work is completed. When the automatic grouting and slurry supplementing equipment is used for slurry supplementing, the plug on the tee joint 4 is unscrewed, and slurry is injected; during the deblocking, the use instrument restores system limiting valve 5 manual, and the pressure release is drained, and the inside recovery spring 8 effect of sealing rubber 7 makes sealing rubber 7 get back to original position, extracts the bag at last and can carry out next hole sealing operation.
As shown in fig. 5, the relationship between the expansion volume of the hole packer and the engagement force is obtained through a simulation experiment, and since the engagement force between the expansion rubber layer and the hole wall cannot be directly measured, but the engagement force is in direct proportion to the friction force between the expansion rubber layer and the hole wall, the engagement force formula can be obtained through measuring the friction force: f = uN; n is the engagement force, f is the friction force, and u is the coefficient of friction.
The invention has simple structure, can realize double sealing, has better sealing effect, can be repeatedly used after pressure relief, solves the problems of insufficient expansion and difficult recovery of the original bag, and is a brand new exploration for reusable equipment in the system.
It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.

Claims (7)

1. The utility model provides a two stifled one notes integral type hydraulic pressure packers of gas drilling that can multiplex, its characterized in that: the gas pipe sealing device comprises a hard supporting rod sleeved outside a gas pipe (1), wherein a sealing bag (11) is sleeved at the tail end of the hard supporting rod, hard plugs (12) sleeved outside the hard supporting rod and the gas pipe (1) and used for axially fixing the sealing bag (11) are arranged at two ends of the sealing bag (11), a water injection pipe and a grouting pipe are arranged in the hard supporting rod, the tail end of the grouting pipe is communicated with an inner cavity of a gas drilling hole through a non-coagulation liquid injection port (9), the tail end of the water injection pipe is communicated with the sealing bag (11) through a hole bottom bag liquid inlet (10), a plurality of sealing rubbers (7) are sleeved at the front end of the hard supporting rod, annular bodies are correspondingly arranged on two sides of each sealing rubber (7), the two annular bodies on the outermost side are connected with a hydraulic cylinder (6), and the liquid inlets of the hydraulic cylinders (6) are communicated with the water injection pipe, the water injection pipe is provided with a system limiting valve (5) for plugging the water injection pipe, and the inside of the sealing rubber (7) is correspondingly provided with a return spring (8).
2. The reusable gas drilling two-plug one-injection integrated hydraulic packer as claimed in claim 1, characterized in that: the tail end of the gas pipe (1) is provided with a floral tube (13).
3. The reusable gas drilling two-plug one-injection integrated hydraulic packer as claimed in claim 1, characterized in that: the tip of water injection pipe is formed with water filling port (2), system limiting valve (5) are close to water filling port (2) end setting.
4. The reusable gas drilling two-plug one-injection integrated hydraulic packer as claimed in claim 1, characterized in that: the end part of the grouting pipe is provided with a tee joint (4), the front end of a straight pipe section of the tee joint (4) is communicated with the grouting pipe on the front side, the rear end of the straight pipe section is communicated with the grouting pipe on the rear side, a grouting opening (3) is formed in the end part of the grouting pipe on the front side, and an upper pipe section of the tee joint (4) is communicated with a pressure gauge.
5. The reusable gas drilling two-plug one-injection integrated hydraulic packer as claimed in claim 1, characterized in that: the reset spring (8) is axially arranged.
6. The reusable gas drilling two-plug one-injection integrated hydraulic packer as claimed in claim 1, characterized in that: the hydraulic cylinders (6) are arranged oppositely and used for extruding the sealing rubber (7).
7. The reusable gas drilling two-plug one-injection integrated hydraulic packer as claimed in claim 1, characterized in that: the head-on of the system limiting valve (5) is in a slope type.
CN202011318644.7A 2020-11-23 2020-11-23 Reusable gas drilling two-plugging one-injection integrated hydraulic packer Active CN112412387B (en)

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Publication number Priority date Publication date Assignee Title
CN113153213B (en) * 2021-05-13 2022-06-10 重庆工程职业技术学院 Gas collection hole plugging device and plugging method thereof
CN113431517A (en) * 2021-06-23 2021-09-24 华能灵台邵寨煤业有限责任公司 Quick plugging device suitable for multi-aperture cyclic multiplexing orifice
CN115790987B (en) * 2023-02-09 2023-06-16 成都凯天电子股份有限公司 Pressure test plug for open end of conduit

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US7334634B1 (en) * 2004-02-02 2008-02-26 Leo William Abel High pressure adaptor assembly for use on blow out preventors
US7197923B1 (en) * 2005-11-07 2007-04-03 Halliburton Energy Services, Inc. Single phase fluid sampler systems and associated methods
CN102996159B (en) * 2012-12-03 2015-04-29 中国矿业大学 Multiphase medium plugging device and method for gas extraction drill hole
CN103711515A (en) * 2013-12-31 2014-04-09 河南能源化工集团研究院有限公司 Reusable multistage gasbag mucus gas extraction drilling and hole sealing device
CN105114030B (en) * 2015-08-20 2018-05-08 中国矿业大学 A kind of non-condensable constant pressure slurries method for sealing of mash gas pumping drilling
CN106223997B (en) * 2016-09-21 2018-05-01 中国矿业大学 A kind of projecting coal bed drilling of high methane and waterpower blanking blowout prevention outburst prevention device and method
CN110608012B (en) * 2019-08-30 2021-11-12 贵州大学 Gas hole packer with pressure relief function
CN110685638A (en) * 2019-11-07 2020-01-14 周春雷 New two-plug one-injection hole packer

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Effective date of registration: 20240222

Address after: Room 127-3, 1st Floor, Haikou Pharmaceutical Valley Biomedical Innovation Complex, No. 288 Nanhai Avenue, Xiuying Street, Xiuying District, Haikou City, Hainan Province, 570100

Patentee after: Hainan Chaowen Qixue Intellectual Property Co.,Ltd.

Country or region after: China

Address before: Room 2313, Building 3, Lemeng Center Mansion, approximately 50 meters west of the intersection of Jingshi Road and Lashan Hedong Road, Huaiyin District, Jinan City, Shandong Province, 250000

Patentee before: Shandong Jinfengyuan Technical Service Co.,Ltd.

Country or region before: China

Effective date of registration: 20240220

Address after: Room 2313, Building 3, Lemeng Center Mansion, approximately 50 meters west of the intersection of Jingshi Road and Lashan Hedong Road, Huaiyin District, Jinan City, Shandong Province, 250000

Patentee after: Shandong Jinfengyuan Technical Service Co.,Ltd.

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Address before: 221116 No. 1 Tongshan University Road, Xuzhou City, Jiangsu Province

Patentee before: CHINA University OF MINING AND TECHNOLOGY

Country or region before: China