CN103485746B - A kind of packer for horizontal well volume fracturing - Google Patents
A kind of packer for horizontal well volume fracturing Download PDFInfo
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- CN103485746B CN103485746B CN201310472098.6A CN201310472098A CN103485746B CN 103485746 B CN103485746 B CN 103485746B CN 201310472098 A CN201310472098 A CN 201310472098A CN 103485746 B CN103485746 B CN 103485746B
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- mandrel
- packer
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- overcoat
- seat
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- 239000004576 sand Substances 0.000 claims abstract description 16
- 238000012856 packing Methods 0.000 claims abstract description 11
- 230000006835 compression Effects 0.000 claims abstract description 10
- 238000007906 compression Methods 0.000 claims abstract description 10
- 229910000831 Steel Inorganic materials 0.000 claims description 25
- 239000010959 steel Substances 0.000 claims description 25
- 238000007789 sealing Methods 0.000 claims description 18
- 238000004026 adhesive bonding Methods 0.000 claims description 3
- 238000000034 method Methods 0.000 abstract description 5
- 238000002347 injection Methods 0.000 abstract description 4
- 239000007924 injection Substances 0.000 abstract description 4
- 239000007788 liquid Substances 0.000 description 17
- 238000010276 construction Methods 0.000 description 4
- 238000006073 displacement reaction Methods 0.000 description 4
- 238000001802 infusion Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 230000007547 defect Effects 0.000 description 1
- 239000003129 oil well Substances 0.000 description 1
- 230000035515 penetration Effects 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
- 238000002407 reforming Methods 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
Landscapes
- Consolidation Of Soil By Introduction Of Solidifying Substances Into Soil (AREA)
Abstract
The invention provides a kind of packer for horizontal well volume fracturing, this packer is column compression packer, comprises ball-and-seat, reacting cycle passage, packing element and mechanical anchor mechanism.Upper ball-and-seat mechanism coordinates reacting cycle passage, meet in oil pipe and the huge discharge injection simultaneously of oil pipe annular space, or only oil pipe annular space huge discharge injects, and meets operational discharge capacity at 10m
3the demand of/more than min.Simultaneously, balanced controls make packer also can carry out the operation of huge discharge reacting cycle under unset state, the sand grains of packer inside is taken away by backwash liquor stream in backwash process, effectively reduces the sand card risk of whole packer inside, is also conducive to the quick deblocking of packer simultaneously.
Description
Technical field
The present invention relates to ultra-low penetration oilfield reservoir reforming equipment field, particularly a kind of packer for horizontal well volume fracturing.
Background technology
The feature of the volume fracturing technology of oil well horizontal well is large liquid measure, huge discharge, large sand amount, and operational discharge capacity is all at 10m
3/ more than min, does not reach design displacement requirements by infusion in oil pipe at all, needs to inject with oil jacket annular space in oil pipe simultaneously, or light sleeve pipe injects.The packer tool being applied to volume fracturing technique at present does not also have comparatively ripe product, can not realize huge discharge infusion.
Summary of the invention
The packer adopted in order to the volume fracturing technique solving horizontal well in prior art can not realize the defect of huge discharge infusion, the invention provides a kind of packer for horizontal well volume fracturing, this packer and hydrajet tool are joined and can be realized hydraulic jet perforation, with the huge discharge injection simultaneously of oil jacket annular space in oil pipe, or only oil jacket annular space huge discharge injects, and meets operational discharge capacity at 10m
3the demand of/more than min.
The present invention is achieved through the following technical solutions:
A kind of packer for horizontal well volume fracturing, this packer is column compression packer, comprise ball-and-seat, reacting cycle passage, packing element and mechanical anchor mechanism, wherein, upper ball-and-seat comprises top connection, mandrel and steel ball, and top connection is connected from outside with mandrel thread, the internal diameter of mandrel bottom is less than upper inner diameter, steel ball one is placed in mandrel, and steel ball one diameter is greater than mandrel lower inner diameter, is less than mandrel upper inner diameter; Be provided with overcoat outside mandrel, the central tube of overcoat tail end from outside with mechanical anchor mechanism is threaded, and overcoat top is connected from inner side with buckle lower thread, and buckle top and mandrel are fitted, and leave space between overcoat and mandrel; Mandrel and overcoat intersection are radially arranged with four through holes, and the through hole on overcoat and mandrel forms reacting cycle passage; Described packing element is positioned at the sunk part near mechanical anchor structure outside overcoat.
Further, packer also comprises balanced controls, and described balanced controls are positioned at mandrel tail end, and with overcoat gluing, sealing, comprise combination sealing group and lower ball-and-seat, combination sealing group is embedded between mandrel and overcoat, and lower single current valve is positioned at inside mandrel, comprises steel ball two and ball seat, ball seat is embedded in inside mandrel, ball seat internal diameter is in middle part to after-contraction, and steel ball two diameter is less than the anterior internal diameter of ball seat, is greater than ball seat rear portion internal diameter; Mandrel afterbody is threaded with buckle two, and buckle two is in the outer side compression combination sealing group of mandrel, and side compression places an order the ball seat of stream valve system in mandrel.
Further, the mandrel end card of upper ball-and-seat mechanism inside top connection has baffle plate one, and the ball seat end card of lower single current valve system inside mandrel has baffle plate two, and described baffle plate one and baffle plate two are equipped with through hole in the axial direction.
Further, mechanical anchor mechanism is rail mounted anchor mechanism, and comprise central tube, positioning joint and sand control structure, positioning joint is enclosed within outside central tube, and sand control structure is the radially symmetrically arranged multiple spline of medial surface of positioning joint tail end.
Upper ball-and-seat mechanism of the present invention coordinates reacting cycle passage, meet in oil pipe and the huge discharge injection simultaneously of oil pipe annular space, or only oil pipe annular space huge discharge injects, and meets operational discharge capacity at 10m
3the demand of/more than min.Simultaneously, balanced controls make packer also can carry out the operation of huge discharge reacting cycle under unset state, the sand grains of packer inside is taken away by backwash liquor stream in backwash process, effectively reduces the sand card risk of whole packer inside, is also conducive to the quick deblocking of packer simultaneously.
Accompanying drawing explanation
Fig. 1 is the structural representation of place of the present invention tubing string;
Fig. 2 is structural representation of the present invention;
Fig. 3 is the partial enlarged drawing of balanced controls of the present invention;
Fig. 4 is the reacting cycle schematic diagram under the present invention sets state;
Fig. 5 is the reacting cycle schematic diagram under unset state of the present invention;
Fig. 6 is the structural representation of mechanical anchor mechanism of the present invention;
Fig. 7 is the A-A sectional view of Fig. 5.
Wherein, 1: top connection; 2: baffle plate one; 3: steel ball one; 4: buckle one; 5: mandrel; 6: overcoat; 7: combination sealing group; 8: baffle plate two; 9: steel ball two; 10: ball seat; 11: packing element; 12: central tube; 13: pin; 14: positioning joint; 15: buckle two; 16: spline; 17: reacting cycle passage; 18: balanced controls; 19: mechanical anchor mechanism; 21: oil pipe; 22: oil pipe annular space; 23: hydrajet tool; 24: packer; 25: other aids; I: reacting cycle liquid flow path direction.
Detailed description of the invention
Below in conjunction with drawings and Examples, the invention will be further described.
As shown in Figure 1, packer 24 of the present invention combines with hydrajet tool 23, utilize in hydraulic jet perforation, oil pipe 21 and oil pipe annular space 22 injects simultaneously, or only oil pipe annular space 22 inject, small displacement companion note in oil pipe 21, by packer 24 packing construction layer, coordinate other aids 25, as fracturing valve instrument etc., carry out from bottom to top the huge discharge volume fracturing construction of successively layering.
Embodiment 1
The invention provides a kind of packer for horizontal well volume fracturing, with reference to shown in Fig. 2, this packer 24 is column compression packer, comprise ball-and-seat, reacting cycle passage 17, packing element 11 and mechanical anchor mechanism 19, wherein, upper ball-and-seat comprises top connection 1, mandrel 5 and steel ball 1, top connection 1 is threaded from outside with mandrel 5, the internal diameter of mandrel 5 bottom is less than upper inner diameter, steel ball 1 is placed in mandrel 5, steel ball 1 diameter is greater than mandrel 5 lower inner diameter, is less than mandrel 5 upper inner diameter, and steel ball 1 is stuck in mandrel 5.Upper ball-and-seat mechanism can stop the top liquid of ball-and-seat mechanism to flow to current downflow, guarantees that perforating job is normally carried out; Meanwhile, in permission, the bottom liquid of ball-and-seat mechanism flows to and pushes steel ball 1 open, enters tubing string inside.Described tubing string refers to the column structure that pit shaft inner oil tube 21 and tool string are formed jointly.
Overcoat 6 is provided with outside mandrel 5, overcoat 6 tail end is threaded from outside with the central tube 12 of mechanical anchor mechanism 19, overcoat 6 top is connected from inner side with buckle 1 lower thread, buckle 1 top and mandrel 5 are fitted, for limiting moving radially of mandrel 5, when ensureing that mandrel 5 moves vertically, overcoat can not be deviate from.
Mandrel 5 and overcoat 6 intersection are radially arranged with four through holes, leave space between overcoat 6 and mandrel 5, and overcoat 6 forms reacting cycle passage 17 with the through hole on mandrel 5.The reacting cycle passage 17 of large area of passage, coordinates the space between overcoat 6 and mandrel 5, ensures reacting cycle operation by relatively rotating the impact with axial displacement between overcoat 6 and mandrel 5.
As shown in Figure 4, I is the direction of reacting cycle liquid stream.When packer 24 is in setting state, liquid in oil pipe annular space 22 flows through the reacting cycle passage 17 on overcoat 6 and mandrel 5, the steel ball 1 pushing ball-and-seat from bottom to top open enters in tubing string, and returned out by well head, achieve the operation of huge discharge reacting cycle, fraction liquid stream can enter tubing string inside through the nozzle of hydrajet tool 23.
Described packing element 11 is positioned near the sunk part of mechanical anchor structure 19 outside overcoat 6, and packing element 11 is squeezed and protrudes overcoat 6 medial plane, shutoff oil pipe annular space 22, coordinate with mechanical anchor mechanism 19 carry out setting.
Embodiment 2
As the improvement to packer described in embodiment 1, as shown in Figure 1, Figure 3, balanced controls 18 are also comprised, these balanced controls 18 are positioned at mandrel 5 tail end, and with overcoat 6 gluing, sealing, comprise combination sealing group 7 and lower ball-and-seat, combination sealing group 7 is embedded between mandrel 5 and overcoat 6, can realize sealing.Lower single current valve is positioned at inside mandrel 5, comprises steel ball 29 and ball seat 10, and ball seat 10 is embedded in inside mandrel 5, ball seat 10 internal diameter is in middle part to after-contraction, steel ball 29 diameter is less than the anterior internal diameter of ball seat 10, is greater than ball seat 10 rear portion internal diameter, steel ball 29 is stuck in ball seat 10.Lower single current valve system can stop liquid in tubing string to flow to the lower inventionannulus flow of packer 24, now can carry out in oil pipe 21 and oil pipe annular space 22 huge discharge injection pressing crack construction, allow liquid stream upwards to flow from lower annular space.Mandrel 5 afterbody is threaded with buckle 2 15, buckle 2 15 in mandrel 5 outer side compression combination sealing group 7, and in mandrel 5 side compression place an order stream valve system ball seat 10.This buckle 2 15 together can move vertically with mandrel 5, compress combination sealing group 7 on the one hand, ensure that in mandrel 5 moving process, combination sealing group 7 can not be deviate from outside mandrel 5, compress lower single current valve system on the other hand, lower single current valve system also together can be moved with mandrel 5 vertically.
Described upper annular space is the cavity between upper ball-and-seat mechanism and lower single current valve system, and lower annular space is the cavity of below lower single current valve system.Balanced controls 18 can balance annular pressure and lower annular pressure on packer 24.Pressing crack construction terminates, and after open flow, recoil terminate, when upper annular pressure is higher than lower annular pressure, as shown in Figure 5, upper lifting pipe post, carries out deblocking to packer 24.Upper lifting force is passed to mandrel 5 through tubing string, top connection 1, axial relative displacement is produced with overcoat 6 by mandrel 5 is carried, combination sealing group 7 is pulled out the inner sealing surface of overcoat 6, the inner side that the high pressure of upper annulus can be passed through overcoat 6 enters lower center tube 12, finally enter lower annular space, realize upper and lower annular pressure balance.Instantly when annular pressure is higher than upper annular pressure, the high pressure liquid stream of lower annular space pushes steel ball 29 open through central tube 12, enters mandrel 5 inner, enters into annular space on packer 24, realizes upper and lower annular pressure balance.In addition, balanced controls 18 are also conducive to the quick deblocking of packer 24.After packer 24 is setting, upper lifting pipe post, pulls out mandrel 5, because upper and lower annular pressure balances, packing element 11 is retracted, and replys reset condition, realizes the quick deblocking of packer 24.
Simultaneously, reacting cycle liquid flow path direction as shown in Fig. 5 I, when balanced controls 18 coordinate upper ball-and-seat mechanism to make packer 24 be in unset state, the reacting cycle liquid reacting cycle passage 17 flowed through on overcoat 6 enters the lower annular space of packer 24, the steel ball 1 of the steel ball 29 and upper ball-and-seat mechanism of pushing lower single current valve system successively open enters in tubing string, and returned out by well head, achieve the operation of huge discharge reacting cycle.
Embodiment 3
As the improvement of embodiment 2, the mandrel 5 end card of upper ball-and-seat mechanism inside top connection 1 has baffle plate 1, and the ball seat 10 end card of lower single current valve system inside mandrel 5 has baffle plate 28, and described baffle plate 1 and baffle plate 28 are equipped with through hole in the axial direction.This through hole ensures that liquid stream can pass through, and steel ball, then by baffle, together can not flow into tubing string because of being pushed open by liquid stream with liquid stream.
Embodiment 4
As the improvement of above-described embodiment, as shown in Figure 6, Figure 7, mechanical anchor mechanism 19 is rail mounted anchor mechanism, comprise central tube 12, positioning joint 14 and sand control structure, positioning joint 14 is enclosed within outside central tube 12, and sand control structure is the radially symmetrically arranged multiple spline 16 of the medial surface of positioning joint 14 tail end.Described mechanical anchor mechanism 19 has downward grappling function, setting for packer 24, the downward hydraulic action that in prevention, the high pressure of annular space produces packer 24.Central tube 12 lateral surface near pin 13 is provided with multiple track groove, for switching tracks of pin 13.Spline 16 on positioning joint 14 medial surface is for sand control, and when there being sand grains in spline 16, the grains of sand flow through spline 16 with liquid and flow out, and avoid the grains of sand to affect pin switching track groove, are conducive to anchor mechanism and repeatedly work.
Upper ball-and-seat mechanism of the present invention coordinates reacting cycle passage, and the needs utilizing the reacting cycle operation of liquid stream to realize oil pipe to inject with huge discharge while of oil pipe annular space, meet operational discharge capacity at 10m
3the demand of/more than min.Meanwhile, the balanced controls of packer ensure that on the one hand packer set with unset state under all can carry out the operation of huge discharge reacting cycle, effectively can reduce the sand card risk of whole packer inside; The pressure differential of the upper and lower annular space of balance packer, is also conducive to quick deblocking on the other hand.
The parts that the present embodiment does not describe in detail and structure belong to the well-known components of the industry and common structure or conventional means, do not describe one by one here.
Claims (3)
1. the packer for horizontal well volume fracturing, described packer is column compression packer, it is characterized in that, comprise ball-and-seat, reacting cycle passage, packing element and mechanical anchor mechanism, wherein, upper ball-and-seat comprises top connection, mandrel and steel ball, top connection is connected from outside with mandrel thread, and the internal diameter of mandrel bottom is less than upper inner diameter, and steel ball one is placed in mandrel, steel ball one diameter is greater than mandrel lower inner diameter, is less than mandrel upper inner diameter; Be provided with overcoat outside mandrel, the central tube of overcoat tail end from outside with mechanical anchor mechanism is threaded, and overcoat top is connected from inner side with buckle lower thread, and buckle top and mandrel are fitted; Mandrel and overcoat intersection are radially arranged with four through holes, leave space between overcoat and mandrel, and the through hole on overcoat and mandrel forms reacting cycle passage; Described packing element is positioned at the sunk part near mechanical anchor structure outside overcoat;
Described packer also comprises balanced controls, described balanced controls are positioned at mandrel tail end, and with overcoat gluing, sealing, comprise combination sealing group and lower ball-and-seat, combination sealing group is embedded between mandrel and overcoat, lower single current valve is positioned at inside mandrel, comprise steel ball two and ball seat, inside the embedding mandrel of ball seat, ball seat internal diameter is in middle part to after-contraction, steel ball two diameter is less than the anterior internal diameter of ball seat, is greater than ball seat rear portion internal diameter; Mandrel afterbody is threaded with buckle two, and buckle two is in the outer side compression combination sealing group of mandrel, and side compression places an order the ball seat of stream valve system in mandrel.
2. packer according to claim 1, it is characterized in that, the mandrel end card of described upper ball-and-seat mechanism inside top connection has baffle plate, and the ball seat end card of lower single current valve system inside mandrel has lower baffle plate, and described baffle plate and lower baffle plate are equipped with through hole in the axial direction.
3. packer according to claim 1, it is characterized in that, described mechanical anchor mechanism is rail mounted anchor mechanism, comprise central tube, positioning joint and sand control structure, positioning joint is enclosed within outside central tube, and described sand control structure is the radially symmetrically arranged multiple spline of medial surface of positioning joint tail end.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310472098.6A CN103485746B (en) | 2013-10-11 | 2013-10-11 | A kind of packer for horizontal well volume fracturing |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310472098.6A CN103485746B (en) | 2013-10-11 | 2013-10-11 | A kind of packer for horizontal well volume fracturing |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN103485746A CN103485746A (en) | 2014-01-01 |
| CN103485746B true CN103485746B (en) | 2015-12-16 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201310472098.6A Active CN103485746B (en) | 2013-10-11 | 2013-10-11 | A kind of packer for horizontal well volume fracturing |
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| CN (1) | CN103485746B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN104863550B (en) * | 2014-02-26 | 2019-09-13 | 中海石油(中国)有限公司上海分公司 | Combined technology of hydraulic sand blasting perforation and APR test |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1505443A (en) * | 1975-11-24 | 1978-03-30 | Otis Eng Corp | Method and apparatus for controlling a well during drilling operations |
| CN101319602A (en) * | 2008-07-23 | 2008-12-10 | 大庆油田有限责任公司 | Single card oil layer blasting hole plugging column |
| CN201574721U (en) * | 2009-12-18 | 2010-09-08 | 沈阳大华测控技术有限公司 | Horizontal well and vertical well fracture packer |
| CN103184867A (en) * | 2013-02-28 | 2013-07-03 | 中国石油集团川庆钻探工程有限公司 | Packer jetting tool ground simulation method suitable for multistage hydraulic jetting fracturing |
| CN103184856A (en) * | 2013-02-28 | 2013-07-03 | 中国石油天然气集团公司 | Hydraulic jet packer applicable to multilevel hydraulic jet fracturing |
| CN203640675U (en) * | 2013-10-11 | 2014-06-11 | 中国石油集团川庆钻探工程有限公司长庆井下技术作业公司 | Packer device used for volume fracturing of horizontal wall |
-
2013
- 2013-10-11 CN CN201310472098.6A patent/CN103485746B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1505443A (en) * | 1975-11-24 | 1978-03-30 | Otis Eng Corp | Method and apparatus for controlling a well during drilling operations |
| CN101319602A (en) * | 2008-07-23 | 2008-12-10 | 大庆油田有限责任公司 | Single card oil layer blasting hole plugging column |
| CN201574721U (en) * | 2009-12-18 | 2010-09-08 | 沈阳大华测控技术有限公司 | Horizontal well and vertical well fracture packer |
| CN103184867A (en) * | 2013-02-28 | 2013-07-03 | 中国石油集团川庆钻探工程有限公司 | Packer jetting tool ground simulation method suitable for multistage hydraulic jetting fracturing |
| CN103184856A (en) * | 2013-02-28 | 2013-07-03 | 中国石油天然气集团公司 | Hydraulic jet packer applicable to multilevel hydraulic jet fracturing |
| CN203640675U (en) * | 2013-10-11 | 2014-06-11 | 中国石油集团川庆钻探工程有限公司长庆井下技术作业公司 | Packer device used for volume fracturing of horizontal wall |
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| CN103485746A (en) | 2014-01-01 |
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Effective date of registration: 20201021 Address after: 100007 Dongcheng District, Dongzhimen, China, North Street, No. 9 Oil Mansion, No. Patentee after: CHINA NATIONAL PETROLEUM Corp. Patentee after: CNPC CHUANQING DRILLING ENGINEERING Co.,Ltd. Address before: 710018 Shaanxi province Xi'an Weiyang Changqing Changqing prosperous Park District Building Room 1207 Patentee before: CHINA NATIONAL PETROLEUM CORPORATION CHUANQING DRILLING ENGINEERING COMPANY LIMITED CHANGQING DOWNHOLE TECHNOLOGY Co. |
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