CN107217997A - Self-styled circulation isolating tool can be closed - Google Patents
Self-styled circulation isolating tool can be closed Download PDFInfo
- Publication number
- CN107217997A CN107217997A CN201710588746.2A CN201710588746A CN107217997A CN 107217997 A CN107217997 A CN 107217997A CN 201710588746 A CN201710588746 A CN 201710588746A CN 107217997 A CN107217997 A CN 107217997A
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- CN
- China
- Prior art keywords
- sand
- self
- styled
- circulating sub
- circulation
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B17/00—Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods; Cables; Casings; Tubings
- E21B17/02—Couplings; joints
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B33/00—Sealing or packing boreholes or wells
- E21B33/10—Sealing or packing boreholes or wells in the borehole
- E21B33/12—Packers; Plugs
- E21B33/1208—Packers; Plugs characterised by the construction of the sealing or packing means
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- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (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)
- Mechanical Engineering (AREA)
- Pipe Accessories (AREA)
Abstract
Self-styled circulation isolating tool can be closed the invention discloses one kind, including positioned at self-styled sand control circulating sub component and packoff nipple component, self-styled sand control circulating sub component and packoff nipple component are connected by being enclosed on the connecting tube of the two outer wall；Top connection connects sand-flushing pipe column to sealing wellhead, is terminated under lower contact above sand-flushing pipe column to sand face.Self-styled sand control circulating sub component is cut off after cutting, and sliding sleeve can axial descending closing circulating sub.The effect of sand control set is to protect circulating sub circulation port.Self-sealing valve can be opened by pressure of spraining, and connect valve upper and lower side pipeline.Packoff nipple component prevents sand washing flow of media with isolating pipe string internal wall laminating, packing sand-flushing pipe column and isolation tubing annulus.Sand washing medium injects from well head, and warp, which can close self-styled circulation isolating tool upper end sand-flushing pipe column, can only enter in sand-flushing pipe column through circulating sub circulation port, finally be sprayed from sand washing head with isolating tubing annulus, medium, and well head is returned out through isolation tubing string and completion tubular column annular space.So as to realize that the sand-flushing pipe column not termination of pumping that makes up a joint continuously is constructed.
Description
Technical field
Self-styled circulation isolating tool can be closed the present invention relates to coal bed gas well sand washing technology, especially one kind.
Background technology
At present, domestic coal bed gas well uses sleeve pipe or sieve tube completion mostly, and coal ash enters with coal bed gas in its recovery process
Enter pit shaft, gradually accumulate, influence gas production is, it is necessary to periodically carry out sand-flushing.Domestic existing sand washing technology mainly has continuously
Oil pipe sand washing technology and conventional oil pipe sand washing technology.
Using coiled tubing sand washing, coordinative composition of equipments cost is high, it is impossible to obtain good economic benefit, and conventional oil pipe is rushed
Sand, sand washing medium is injected by well mouth oil pipe, and making up a joint needs termination of pumping to operate, and sand washing process is discontinuous, and now coal dust falls after rise, is held
Easily there is the risk of sand card.
The content of the invention
The technical problems to be solved by the invention, which are to provide one kind, can close self-styled circulation isolating tool, can be without using
Coiled tubing realizes the technology of continuous sand flushing.
In order to solve the above-mentioned technical problem, the technical solution adopted by the present invention is：One kind can close self-styled circulation packing work
Tool, including self-styled sand control circulating sub component and underlying packoff nipple component above, self-styled sand control circulation are short
Section component and packoff nipple component are connected by being enclosed on the connecting tube of the two outer wall；
Self-styled sand control circulating sub component include top connection, circulating sub, protective case, jump ring, sealing ring, explosion plate valve,
Movable sleeve, sealing ring, cut off, top connection, connecting tube and circulating sub are connected through a screw thread, and will be coordinated by gap and be arranged on
Protective case outside circulating sub is fixed, and movable sleeve is arranged on circulating sub internal upper part, is realized and sealed by two groups of sealing rings, living
Dynamic set initial position is limited by cutting off, and movable sleeve inner upper end, which is formed with, extends out step, and explosion plate valve is arranged on movable set upper side
Extend out in step, realized and sealed by two groups of sealing rings, the top of explosion plate valve is fixed by jump ring；In circulating sub inwall
Bottom is provided with limiting stand, for controlling movable sleeve downward storke after cutting off, in limiting stand and the guarantor positioned at initial position
Equally distributed circulation port along the axial and circumferential directions is designed with circulating sub body between sheath lower end, limiting stand blocks descending
Movable sleeve when, the descending closing circulation port of movable sleeve；
Packoff nipple component include central tube, multiple retainer rings, multiple seals and lower contact, connecting tube, central tube, under
It is threadedly coupled between joint, multiple seals are enclosed on central tube using interference fit, between two neighboring seal, connecting tube
Retainer ring is set respectively between adjacent seals, between lower contact and adjacent seals, and limit is tightened by upper and lower joint
Position；Seal is the internal round platform for carrying through hole, is provided with the minor diameter bottom end of round platform outer wall inside outer step, seal
Through-hole structure be：The circular hole being interference fitted with central tube external diameter, close to round platform major diameter bottom end, circular hole is connected with turn outer
The interior step and horn mouth expanded, the male cone (strobilus masculinus) of round platform is the sealing cone with isolated tube column sealing, and horn mouth provides for seal
Extruding allowance, retainer ring matches with outer step and interior step, and outer step and interior step are used to block retainer ring；
Top connection connects sand-flushing pipe column to sealing wellhead, is terminated under lower contact above sand-flushing pipe column to sand face.
The protective case is coordinated with circulating sub using gap, fit clearance 0.05-0.1mm.
The circulation port aperture of the circulating sub design is 5mm, circumferentially with axially uniform Boulez.
Chamfering is provided with the male cone (strobilus masculinus) contacted with isolation tubing string, is easy to avoid scratch from sealing when tubing string is up and down
Part upper surface.
The seal is made of the high abrasion fluorubber of addition graphite content.
The seal installs 2 altogether.
The beneficial effects of the invention are as follows：Routine oil pipe can be used to realize continuous sand washing technique；Save coiled tubing sand washing into
This.
Brief description of the drawings
Fig. 1 is the structural representation for the self-styled sand control circulating sub component that the present invention can close self-styled circulation isolating tool.
Fig. 2 is the structural representation for the packoff nipple component that the present invention can close self-styled circulation isolating tool.
Fig. 3 is the structural representation of the seal for the packoff nipple component that the present invention can close self-styled circulation isolating tool.
Fig. 4 is structural representation when the present invention can close the work of self-styled circulation isolating tool.
Fig. 5 is structural representation when the present invention can close the closing of self-styled circulation isolating tool.
Embodiment
The present invention is described in further detail with reference to the accompanying drawings and detailed description：
As Figure 1-5, it is of the invention to close self-styled circulation isolating tool, including self-styled sand control circulation above
Pipe nipple component 31 and underlying packoff nipple component 32, self-styled sand control circulating sub component and packoff nipple component 32 pass through
The connecting tube 30 for being enclosed on the two outer wall is connected；
Self-styled sand control circulating sub component 31 includes top connection 1, circulating sub 2, protective case 3, jump ring 4, sealing ring 5, quick-fried
Fragmentation valve 6, movable sleeve 7, sealing ring 8, cut off 9, top connection 1, connecting tube 30 and circulating sub 2 and be connected through a screw thread, and will be logical
Crossing gap coordinates the protective case 3 being arranged on outside circulating sub 2 to fix, and movable sleeve 7 is arranged on the internal upper part of circulating sub 2, passes through
Two groups of sealing rings 8 realize sealing, and the initial position of movable sleeve 7 is limited by cutting off 9, and the inner upper end of movable sleeve 7, which is formed with, extends out step,
Explosion plate valve 6 is extended out in step installed in the upper end of movable sleeve 7, is passed through two groups of sealing rings 5 and is realized sealing, the top of explosion plate valve 6
End is fixed by jump ring 4；The inner wall lower of circulating sub 2 is provided with limiting stand 11, for controlling movable sleeve 7 after cutting off 9
Downward storke, is designed with along axle on limiting stand 11 and the body of circulating sub 2 between the lower end of protective case 3 of initial position
To with circumferential equally distributed circulation port 2-1, when limiting stand 11 blocks descending movable sleeve 7, the descending closing circulation port of movable sleeve 7
2-1；
Packoff nipple component 32 includes central tube 22, multiple retainer rings, multiple seals 24 and lower contact 28, connecting tube
30th, it is threadedly coupled between central tube 22, lower contact 28, multiple seals 24 are enclosed on central tube 22 using interference fit, adjacent
Set respectively between two seals 24, between connecting tube 30 and adjacent seals 24, between lower contact 28 and adjacent seals 24
Retainer ring is put, and is tightened by upper and lower joint spacing；Seal 24 is the internal round platform for carrying through hole, in the small of round platform outer wall
The through-hole structure that diameter base end is provided with inside outer step 24-5, seal 24 is：It is interference fitted with the external diameter of central tube 22
Circular hole 24-6, close to round platform major diameter bottom end, circular hole 24-6 is connected with the interior step 24-4 and horn mouth 24-2 extended out in turn,
The male cone (strobilus masculinus) 24-3 of round platform is that horn mouth 24-2 provide extruding allowance for seal with isolating the sealed sealing cone of tubing string 29,
Retainer ring matches with outer step 24-5 and interior step 24-4, and outer step 24-5 and interior step 24-4 are used to block retainer ring；
Top connection 1 connects sand-flushing pipe column to sealing wellhead, 28 times termination sand-flushing pipe columns of lower contact to sand faces top.
The protective case 3 is coordinated with circulating sub 2 using gap, fit clearance 0.05-0.1mm.
The circulation port 2-1 apertures that the circulating sub 2 is designed are 5mm, circumferentially with axially uniform Boulez.
Chamfering 24-1 is provided with the male cone (strobilus masculinus) 24-3 contacted with isolation tubing string 29, is easy to keep away when tubing string is up and down
Exempt from scratch seal upper surface.
The seal 24 is made of the high abrasion fluorubber of addition graphite content.
The seal 24 installs 2 altogether.
After self-styled sand control circulating sub component 31 is connected with sand-flushing pipe column, due to the plugging action of its explosion plate valve 6, sand washing
Medium can not be injected by well head sand-flushing pipe column, can only be injected from annular space, then enter bottom sand clean out pipe from the instrument circulation port
Post, realizes sand washing.So as to realize that the not termination of pumping that makes up a joint of sand washing process is worked continuously.Need directly to irrigate from well head top oil pipe
During sand washing, circulation port 2-1 can be closed, pressure of spraining, which punctures the valve block of explosion plate valve 6, connects lower tubular column.Can be from well head top oil
Pipe directly perfusion sand washing cuts off 9 closing circulation port 2-1, it is necessary to which compression shear of spraining is disconnected, and the pressure that continues to sprain punctures above and below the valve block of explosion plate valve 6 makes
Tubing string is connected.
After packoff nipple component 32 is connected with sand-flushing pipe column, because its seal 24 male cone (strobilus masculinus) 24-1 is with isolating in tubing string 29
Surface gluing, sealing, fluid cannot pass through sand-flushing pipe column and be flowed with isolating above and below the annular space between tubing string 29.Seal 24 is used
The high abrasion fluorubber of addition graphite content is made, with heat resistant and wear resistant effect.Seal 24 is designed with outer step 24-5, interior
Step 24-4, horn mouth 24-2, male cone (strobilus masculinus) 24-3.Outer step 24-5, interior step 24-4 are used for matching somebody with somebody for retainer ring 23,25,26,27
Close, male cone (strobilus masculinus) 24-3 is with isolating the sealed sealing cone of tubing string 29.The horn mouth 24-2 seal that is designed as is provided more than extruding
Amount.Chamfering 24-1 is easy to avoid scratch seal upper surface when tubing string is up and down between male cone (strobilus masculinus) 24-3 and upper surface.The work
After tool is connected with sand-flushing pipe column, due to the sealing function of its seal, fluid cannot pass through sand-flushing pipe column with isolating between tubing string
Annular space above and below flow.
During the two synergy, top connection 1 connects sand-flushing pipe column to sealing wellhead, 28 times termination sand-flushing pipe columns of lower contact to sand
Above face.First tripping in isolation tubing string 29 and sit hangs over well head, then tripping in sand-flushing pipe column and can close it is self-styled circulation packing
Instrument is connected on sand-flushing pipe column, self-styled circulating sub component, the packoff nipple component designed by it, realizes sand washing medium not
Injected, and injected by sand clean out pipe with isolating the outer annular space of tubing string 29 by well mouth oil pipe, without termination of pumping when making up a joint, realized continuous
The function of sand washing.
Sand washing medium injects from well head, and warp can close self-styled circulation isolating tool upper end sand-flushing pipe column and the isolated tube band of column
Sky, due to the effect of packoff nipple component, medium can only enter in sand-flushing pipe column through circulating sub circulation port, due to explosion plate valve
Packing effect, make sand washing medium descending, finally from sand washing head spray, through isolate tubing string 29 returned with the annular space of completion tubular column 35
Go out well head.So as to realize that the sand-flushing pipe column not termination of pumping that makes up a joint continuously is constructed.As sand-flushing pipe column is constantly descending, when packoff nipple group
When exceeding deep under isolation tubing string deeply under part, seal failure.Therefore, sealing is lost when packoff nipple component soon departs from isolation tubing string
During effect, close it is self-styled circulation shorted component circulation port, open circulating sub Self-sealing valve, then access again a set of sand flushing device after
Continuous construction, until sand washing terminates.
In summary, present disclosure is not limited in the above embodiments, and the knowledgeable people in same area can
Can propose other embodiments easily within the technological guidance's thought of the present invention, but this embodiment is included in this hair
Within the scope of bright.
Claims (6)
1. one kind can close self-styled circulation isolating tool, it is characterised in that including self-styled sand control circulating sub group above
Part (31) and underlying packoff nipple component (32), self-styled sand control circulating sub component and packoff nipple component (32) pass through
The connecting tube (30) for being enclosed on the two outer wall is connected；
Self-styled sand control circulating sub component (31) includes top connection (1), circulating sub (2), protective case (3), jump ring (4), sealing
Circle (5), explosion plate valve (6), movable sleeve (7), sealing ring (8), cut off (9), top connection (1), connecting tube (30) and circulating sub
(2) it is connected through a screw thread, and will coordinates fixed installed in the outside protective case (3) of circulating sub (2) by gap, movable sleeve
(7) circulating sub (2) internal upper part is arranged on, is realized and sealed by two groups of sealing rings (8), movable sleeve (7) initial position is by cutting off
(9) limit, movable sleeve (7) inner upper end, which is formed with, extends out step, explosion plate valve (6) is arranged on extending out for movable sleeve (7) upper end
In step, realized and sealed by two groups of sealing rings (5), the top of explosion plate valve (6) is fixed by jump ring (4)；In circulating sub
(2) inner wall lower is provided with limiting stand (11), movable sleeve (7) downward storke is controlled afterwards for cutting off (9), in limiting stand
(11) and on circulating sub (2) body between protective case (3) lower end of initial position it is designed with equal along the axial and circumferential directions
The circulation port (2-1) of even distribution, when limiting stand (11) blocks descending movable sleeve (7), the descending closing circulation port of movable sleeve (7)
(2-1)；
Packoff nipple component (32) includes central tube (22), multiple retainer rings, multiple seals (24) and lower contact (28), connection
Manage and be threadedly coupled between (30), central tube (22), lower contact (28), multiple seals (24) are enclosed on central tube using interference fit
(22) on, between two neighboring seal (24), between connecting tube (30) and adjacent seals (24), lower contact (28) with it is adjacent
Retainer ring is set respectively between seal (24), and tightened by upper and lower joint spacing；Seal (24) carries through hole to be internal
Round platform, the minor diameter bottom end of round platform outer wall is provided with outer step (24-5), the internal through-hole structure of seal (24) is：
The circular hole (24-6) being interference fitted with central tube (22) external diameter, close to round platform major diameter bottom end, circular hole (24-6) is sequentially connected
There is an interior step (24-4) and horn mouth (24-2) extended out, the male cone (strobilus masculinus) (24-3) of round platform is and isolate tubing string (29) sealed close
The conical surface is sealed, horn mouth (24-2) provides extruding allowance, retainer ring and outer step (24-5) and interior step (24-4) phase for seal
Matching, outer step (24-5) and interior step (24-4) are used to block retainer ring；
Top connection (1) connects sand-flushing pipe column to sealing wellhead, is terminated under lower contact (28) above sand-flushing pipe column to sand face.
2. self-styled circulation isolating tool can be closed according to claim 1, it is characterised in that the protective case (3) and circulation
Pipe nipple (2) is coordinated using gap, fit clearance 0.05-0.1mm.
3. self-styled circulation isolating tool can be closed according to claim 1, it is characterised in that circulating sub (2) design
Circulation port (2-1) aperture be 5mm, circumferentially with axially uniform Boulez.
4. self-styled circulation isolating tool can be closed according to claim 1, it is characterised in that described to be connect with isolating tubing string (29)
Chamfering (24-1) is provided with tactile male cone (strobilus masculinus) (24-3), is easy to avoid scratch seal upper surface when tubing string is up and down.
5. self-styled circulation isolating tool can be closed according to claim 1, it is characterised in that the seal (24), which uses, to be added
Plus the high abrasion fluorubber of graphite content is made.
6. self-styled circulation isolating tool can be closed according to claim 1, it is characterised in that the seal (24) is installed altogether
2.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710588746.2A CN107217997B (en) | 2017-07-18 | 2017-07-18 | Self-styled circulation isolating tool can be closed |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710588746.2A CN107217997B (en) | 2017-07-18 | 2017-07-18 | Self-styled circulation isolating tool can be closed |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107217997A true CN107217997A (en) | 2017-09-29 |
| CN107217997B CN107217997B (en) | 2019-01-22 |
Family
ID=59952698
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710588746.2A Active CN107217997B (en) | 2017-07-18 | 2017-07-18 | Self-styled circulation isolating tool can be closed |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107217997B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114320195A (en) * | 2022-01-07 | 2022-04-12 | 西安石油大学 | Reversing connector for continuous sand washing and well washing |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4744420A (en) * | 1987-07-22 | 1988-05-17 | Atlantic Richfield Company | Wellbore cleanout apparatus and method |
| CN2586812Y (en) * | 2002-11-07 | 2003-11-19 | 辽河石油勘探局工程技术研究院 | Continuous sand flushing tool |
| CN2898267Y (en) * | 2006-06-04 | 2007-05-09 | 冯力 | Positive sand washer |
| CN201068748Y (en) * | 2007-10-17 | 2008-06-04 | 大庆油田有限责任公司 | Horizontal well continue sand-flushing device |
| CN201567983U (en) * | 2009-12-09 | 2010-09-01 | 中国石油天然气股份有限公司 | Coal-bed gas well bridge type pollution-free continuous coal ash washing process pipe column |
-
2017
- 2017-07-18 CN CN201710588746.2A patent/CN107217997B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4744420A (en) * | 1987-07-22 | 1988-05-17 | Atlantic Richfield Company | Wellbore cleanout apparatus and method |
| CN2586812Y (en) * | 2002-11-07 | 2003-11-19 | 辽河石油勘探局工程技术研究院 | Continuous sand flushing tool |
| CN2898267Y (en) * | 2006-06-04 | 2007-05-09 | 冯力 | Positive sand washer |
| CN201068748Y (en) * | 2007-10-17 | 2008-06-04 | 大庆油田有限责任公司 | Horizontal well continue sand-flushing device |
| CN201567983U (en) * | 2009-12-09 | 2010-09-01 | 中国石油天然气股份有限公司 | Coal-bed gas well bridge type pollution-free continuous coal ash washing process pipe column |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114320195A (en) * | 2022-01-07 | 2022-04-12 | 西安石油大学 | Reversing connector for continuous sand washing and well washing |
| CN114320195B (en) * | 2022-01-07 | 2023-08-22 | 西安石油大学 | A reversing joint for continuous sand flushing and well flushing |
Also Published As
| Publication number | Publication date |
|---|---|
| CN107217997B (en) | 2019-01-22 |
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Effective date of registration: 20210910 Address after: 100007 No. 9 North Main Street, Dongcheng District, Beijing, Dongzhimen Patentee after: CHINA NATIONAL PETROLEUM Corp. Patentee after: CNPC Bohai Drilling Engineering Co.,Ltd. Address before: China Petroleum Tianjin building Bohai Drilling Engineering Co., Ltd., No. 83, Second Street, economic and Technological Development Zone, Binhai New Area, Tianjin, 300457 Patentee before: CNPC Bohai Drilling Engineering Co.,Ltd. |
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