CN107288572A - Blind hole type circulates isolating tool - Google Patents
Blind hole type circulates isolating tool Download PDFInfo
- Publication number
- CN107288572A CN107288572A CN201710584800.6A CN201710584800A CN107288572A CN 107288572 A CN107288572 A CN 107288572A CN 201710584800 A CN201710584800 A CN 201710584800A CN 107288572 A CN107288572 A CN 107288572A
- Authority
- CN
- China
- Prior art keywords
- blind hole
- sand
- hole type
- connecting tube
- circulating sub
- 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.)
- Granted
Links
- 238000011010 flushing procedure Methods 0.000 claims abstract description 28
- 239000004576 sand Substances 0.000 claims abstract description 25
- 210000002445 nipple Anatomy 0.000 claims abstract description 20
- 238000007789 sealing Methods 0.000 claims abstract description 18
- 238000002955 isolation Methods 0.000 claims description 6
- 230000001681 protective effect Effects 0.000 claims description 5
- 238000005299 abrasion Methods 0.000 claims description 4
- 239000000203 mixture Substances 0.000 claims description 2
- 238000004080 punching Methods 0.000 claims 1
- 239000004575 stone Substances 0.000 claims 1
- 238000005406 washing Methods 0.000 abstract description 16
- 238000005086 pumping Methods 0.000 abstract description 4
- 230000000694 effects Effects 0.000 abstract description 3
- 238000012856 packing Methods 0.000 abstract description 2
- 238000005516 engineering process Methods 0.000 description 6
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 3
- 239000003245 coal Substances 0.000 description 3
- 229910002804 graphite Inorganic materials 0.000 description 3
- 239000010439 graphite Substances 0.000 description 3
- 239000012530 fluid Substances 0.000 description 2
- 238000004026 adhesive bonding Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000010883 coal ash Substances 0.000 description 1
- 239000002817 coal dust Substances 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
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
- 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
-
- 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
- E21B21/00—Methods or apparatus for flushing boreholes, e.g. by use of exhaust air from motor
-
- 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
- E21B37/00—Methods or apparatus for cleaning boreholes or wells
Landscapes
- 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)
- Earth Drilling (AREA)
Abstract
Isolating tool, including blind hole type circulating sub component and underlying packoff nipple component above are circulated the invention discloses a kind of blind hole type, blind hole type circulating sub component and packoff nipple component are connected by being enclosed on the connecting tube of the two outer wall；Upper connecting tube connects sand-flushing pipe column to sealing wellhead, is terminated under lower contact above sand-flushing pipe column to sand face.Sand washing medium injects from well head, through blind hole type circulation isolating tool upper end sand-flushing pipe column with isolating tubing annulus, due to the effect of packoff nipple component, medium can only enter in sand-flushing pipe column through blind hole type circulating sub component circulation port, because the packing of blind plate is acted on, make sand washing medium descending, finally sprayed from sand washing head, well head is returned out through isolating 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
The present invention relates to coal bed gas well sand washing technology, especially a kind of blind hole type circulation isolating tool.
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 are to provide a kind of blind hole type circulation isolating tool, can be without using continuous
Oil pipe 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：A kind of blind hole type circulates isolating tool, bag
Include blind hole type circulating sub component and underlying packoff nipple component above, blind hole type circulating sub component and close
Envelope pipe nipple component is connected by being enclosed on the connecting tube of the two outer wall；
Blind hole type circulating sub component includes upper connecting tube, jump ring, blind plate, sealing ring, connector, circulating sub, protection
The upper end of set, upper connecting tube and circulating sub is formed integrally by being enclosed on the connector on the outside of both through threaded connection, connecting tube
The lower end of circulating sub is threadedly attached in, protective case is designed as slot structure, is coordinated using gap and be arranged on circulating sub
Outside, and by connector and connecting tube fix；Limited step is provided with upper connecting tube, blind plate is by being threadably mounted at limiting stand
Rank top, is realized using one group of sealing ring and sealed, and is provided with the top of blind plate on the jump ring of fixed blind plate, circulating sub and is designed with edge
The equally distributed circulation port of axial and circumferential；
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；
Upper connecting tube connects sand-flushing pipe column to sealing wellhead, is terminated under lower contact above sand-flushing pipe column to sand face.
The blind plate top design has one group of mounting hole, convenient to install.
Circulation port is uniformly distributed along the axial and circumferential directions, a hole of staggering between adjacent two row.
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.
Isolate tubing string lower depth will with it is deep supporting under sand-flushing pipe column, it is ensured that packoff nipple component insulate all the time isolation tubing string with
Annular space between sand-flushing pipe column.
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 of the blind hole type circulating sub component of blind hole type circulation isolating tool of the present invention.
Fig. 2 is the structural representation of the packoff nipple component of blind hole type circulation isolating tool of the present invention.
Fig. 3 is the structural representation of the packoff nipple component seal of blind hole type circulation isolating tool of the present invention.
Fig. 4 is the structural representation that blind hole type of the present invention circulates isolating tool.
Embodiment
The present invention is described in further detail with reference to the accompanying drawings and detailed description：
As Figure 1-4, blind hole type of the invention circulation isolating tool, including blind hole type circulating sub group above
Part 31 and underlying packoff nipple component 32, blind hole type circulating sub component 31 and packoff nipple component 32 are by being enclosed on two
The connecting tube 30 of person's outer wall is connected；
Blind hole type circulating sub component 31 is short including upper connecting tube 1, jump ring 2, blind plate 3, sealing ring 4, connector 5, circulation
The upper end of section 6, protective case 7, upper connecting tube 1 and circulating sub 6 is formed by being enclosed on the connector 5 on the outside of both through threaded connection
One, connecting tube 30 is threadedly attached in the lower end of circulating sub 6, and protective case 7 is designed as slot structure 7-1, using gap
Coordinate and be arranged on outside circulating sub 6, and fixed by connector 5 and connecting tube 30；Limited step is provided with upper connecting tube 1,
Blind plate 3 is realized using one group of sealing ring 4 and sealed, fixation is provided with the top of blind plate 3 blind by being threadably mounted at limited step top
Equally distributed circulation port 6-1 along the axial and circumferential directions is designed with the jump ring 2 of plate, circulating sub 6；
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；
Upper connecting tube 1 connects sand-flushing pipe column to sealing wellhead, 28 times termination sand-flushing pipe columns of lower contact to sand faces top.
The top design of blind plate 3 has one group of mounting hole 3-1, convenient to install.
Circulation port 6-1 is uniformly distributed along the axial and circumferential directions, a hole of staggering between adjacent two row.
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.
The lower depth for isolating tubing string 29 is supporting with depth under sand-flushing pipe column, it is ensured that packoff nipple component 32 insulates isolated tube all the time
Annular space between post 29 and sand-flushing pipe column.
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.
First tripping in isolation tubing string and sit hangs over well head, then tripping in sand-flushing pipe column and by blind hole type circulation isolating tool connect
It is connected on sand-flushing pipe column, blind hole type circulating sub component, the packoff nipple component designed by it realizes that sand washing medium does not pass through
Well mouth oil pipe injects, and, without termination of pumping when making up a joint, realizes continuous sand flushing with isolating the sky injection of tubing string outer shroud by sand clean out pipe
Function.
Sand washing medium is injected from well head, and isolating tool upper end sand-flushing pipe column is circulated with isolating the annular space of tubing string 29 through blind hole type,
Due to the effect of packoff nipple component 32, medium can only enter in sand-flushing pipe column through blind hole type circulating sub component circulation port, by
Acted in the packing of blind plate, make sand washing medium descending, finally sprayed from sand washing head, through isolating tubing string 29 and completion tubular column 35
Annular space returns 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.
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 (7)
1. a kind of blind hole type circulates isolating tool, it is characterised in that including blind hole type circulating sub component (31) above
With underlying packoff nipple component (32), blind hole type circulating sub component (31) and packoff nipple component (32) are by being enclosed on
The connecting tube (30) of the two outer wall is connected；
Blind hole type circulating sub component (31) includes upper connecting tube (1), jump ring (2), blind plate (3), sealing ring (4), connector
(5) upper end of, circulating sub (6), protective case (7), upper connecting tube (1) and circulating sub (6) passes through the company that is enclosed on the outside of both
Joint (5) forms one through threaded connection, and connecting tube (30) is threadedly attached in the lower end of circulating sub (6), protective case (7)
Slot structure (7-1) is designed as, is coordinated using gap and is arranged on circulating sub (6) outside, and pass through connector (5) and connecting tube
(30) it is fixed；Limited step is provided with upper connecting tube (1), blind plate (3) is by being threadably mounted at limited step top, using one
Group sealing ring (4) realizes the jump ring (2) that fixed blind plate is provided with the top of sealing, blind plate (3), and circulating sub is designed with edge on (6)
The equally distributed circulation port of axial and circumferential (6-1)；
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；
Upper connecting tube (1) connects sand-flushing pipe column to sealing wellhead, is terminated under lower contact (28) above sand-flushing pipe column to sand face.
2. blind hole type circulates isolating tool according to claim 1, it is characterised in that blind plate (3) top design has one
Group mounting hole (3-1), it is convenient to install.
3. blind hole type circulates isolating tool according to claim 1, it is characterised in that circulation port (6-1) is along the axial and circumferential directions
It is uniformly distributed, a hole of staggering between adjacent two row.
4. blind hole type circulation isolating tool according to claim 1, it is characterised in that described to be contacted with isolating tubing string (29)
Chamfering (24-1) is provided with male cone (strobilus masculinus) (24-3), is easy to avoid scratch seal upper surface when tubing string is up and down.
5. blind hole type circulates isolating tool according to claim 1, it is characterised in that the seal (24) is using addition stone
The high abrasion fluorubber of black composition is made.
6. blind hole type circulates isolating tool according to claim 1, it is characterised in that the seal (24) installs 2 altogether.
7. blind hole type circulates isolating tool according to claim 1, it is characterised in that the lower depth of isolation tubing string (29) will be with punching
It is deep supporting under sandpipe post, it is ensured that packoff nipple component (32) insulates isolation tubing string (29) annular space between sand-flushing pipe column all the time.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710584800.6A CN107288572B (en) | 2017-07-18 | 2017-07-18 | Blind hole type recycles isolating tool |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710584800.6A CN107288572B (en) | 2017-07-18 | 2017-07-18 | Blind hole type recycles isolating tool |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107288572A true CN107288572A (en) | 2017-10-24 |
| CN107288572B CN107288572B (en) | 2019-04-12 |
Family
ID=60100952
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710584800.6A Active CN107288572B (en) | 2017-07-18 | 2017-07-18 | Blind hole type recycles isolating tool |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107288572B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109869113A (en) * | 2017-12-01 | 2019-06-11 | 中石化石油工程技术服务有限公司 | A kind of packing formula stage cementing device |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3760878A (en) * | 1972-03-16 | 1973-09-25 | Amoco Prod Co | Perforations washing tool |
| US4211280A (en) * | 1978-09-29 | 1980-07-08 | Yeates Robert D | Downhole surge tools, method and apparatus |
| WO1994013929A1 (en) * | 1992-12-09 | 1994-06-23 | Baker Hughes Incorporated | Method and apparatus for cleaning wellbore perforations |
| CN2495803Y (en) * | 2001-06-25 | 2002-06-19 | 尹旭东 | Sealing type well flushing able packer |
| CN2687325Y (en) * | 2003-12-24 | 2005-03-23 | 尹婷 | Integrated underground tool string |
| CN101498204A (en) * | 2009-02-25 | 2009-08-05 | 大庆油田有限责任公司 | Balance type step-by-step releasable flushing packer |
| CN201705276U (en) * | 2010-06-11 | 2011-01-12 | 大港油田集团有限责任公司 | Well completion and flow string of horizontal well |
| CN106150428A (en) * | 2015-03-27 | 2016-11-23 | 中国石油化工股份有限公司 | Split type exempting from bores plug completion tubular column and completion method thereof |
-
2017
- 2017-07-18 CN CN201710584800.6A patent/CN107288572B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3760878A (en) * | 1972-03-16 | 1973-09-25 | Amoco Prod Co | Perforations washing tool |
| US4211280A (en) * | 1978-09-29 | 1980-07-08 | Yeates Robert D | Downhole surge tools, method and apparatus |
| WO1994013929A1 (en) * | 1992-12-09 | 1994-06-23 | Baker Hughes Incorporated | Method and apparatus for cleaning wellbore perforations |
| CN2495803Y (en) * | 2001-06-25 | 2002-06-19 | 尹旭东 | Sealing type well flushing able packer |
| CN2687325Y (en) * | 2003-12-24 | 2005-03-23 | 尹婷 | Integrated underground tool string |
| CN101498204A (en) * | 2009-02-25 | 2009-08-05 | 大庆油田有限责任公司 | Balance type step-by-step releasable flushing packer |
| CN201705276U (en) * | 2010-06-11 | 2011-01-12 | 大港油田集团有限责任公司 | Well completion and flow string of horizontal well |
| CN106150428A (en) * | 2015-03-27 | 2016-11-23 | 中国石油化工股份有限公司 | Split type exempting from bores plug completion tubular column and completion method thereof |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109869113A (en) * | 2017-12-01 | 2019-06-11 | 中石化石油工程技术服务有限公司 | A kind of packing formula stage cementing device |
Also Published As
| Publication number | Publication date |
|---|---|
| CN107288572B (en) | 2019-04-12 |
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Effective date of registration: 20210926 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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