CN102953706B - Washable well packer for realizing underground secondary setting - Google Patents
Washable well packer for realizing underground secondary setting Download PDFInfo
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- CN102953706B CN102953706B CN201210529974.XA CN201210529974A CN102953706B CN 102953706 B CN102953706 B CN 102953706B CN 201210529974 A CN201210529974 A CN 201210529974A CN 102953706 B CN102953706 B CN 102953706B
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Abstract
The invention discloses a washable well packer for realizing underground secondary setting and relates to a packer. The packer comprises a well-washing mechanism, a sealing mechanism, a locking mechanism, a setting mechanism and a de-blocking mechanism, wherein the well-washing mechanism comprises an upper joint, a top sleeve, a well-washing valve and a sealing ring I; the sealing mechanism comprises an outer center pipe, three rubber cylinders, two separating rings and a sealing ring; the locking mechanism comprises a slip seat, a valving inner slip and a locking sleeve; the setting mechanism mainly comprises an upper piston, a lower piston, a valve seat and a setting valve; and the de-blocking mechanism is a de-blocking sleeve. Due to the adoption of the setting valve, after the upper piston finishes setting for one time, a valve sleeve travels upwards, a liquid inlet of the valve is opened, when the external liquid pressure reaches set value of a valve switch, liquid flow outside a pipe is filled into a hydraulic cavity of the lower piston through a liquid flow passage, secondary setting is realized, and the defects that the inner pressure and the outer pressure of a pipe post is are unbalanced, a casing pipe is easy to damage in a using process, de-blocking is difficultly operated or de-blocking cannot be operated in the prior art are overcome.
Description
Technical field
Technical scheme of the present invention relates to the packing of well, specifically a kind of well packer capable of flushing well realizing down-hole secondary and set.
Background technology
Occur to prevent sand pipe laying post phenomenon, water injection well packer many employings washing well formula on current oil field, as Y341-114 type water injection packer, but this type of packer to set pressure low, through repeatedly well-flushing operation, easily cause tubing string external and internal pressure unbalance, long term causes packing element to wriggle, seal failure occurs ahead of time, makes the packer lost of life.For solving the problem, there is following several method: 1. increase setting force by mending envelope technique.CN101008311 discloses benefit envelope technique when K type downhole packer does not seal, and its shortcoming is and is fundamentally solve the unbalance situation of tubing string external and internal pressure, and technological operation is numerous and diverse and the effect cycle is not long; 2. hydraulic anchor and hydraulic slip are set on packer construction.Although adopt hydraulic anchor or hydraulic slip to reach the effect of equilibrium pressure, cause packer complicated integral structure, manufacture difficulty, use cost is very high, and easily causes the damage to sleeve pipe.3. by cutting off the packer of pin deblocking.This packer is in use due to the requirement of pressure, and its diameter continues to increase from top to bottom, cost and structural requirement strict.Along with the increasing of influence factor of external environment, the problem of existing well packer in use ubiquity deblocking difficulty or not deblocking.In well workover process, due to packer not deblocking, can only pull out by force during lift pipe string, the phenomenon causing oil pipe to be broken happens occasionally, and cause great down-hole accident thus, workover cost increases greatly.
Summary of the invention
Technical problem to be solved by this invention is: a kind of well packer capable of flushing well realizing down-hole secondary and set, be provided with in setting mechanism and set valve, after upper piston completes and once sets, valve cover is up, open the inlet of valve, when outer hydraulic coupling reaches the setting value of valve switch, manage outer liquid and flow through fluid course injection lower piston hydraulic cavities, realize secondary to set, overcome tubing string external and internal pressure in the well packer of prior art unbalance, packer complicated integral structure, the damage to sleeve pipe and ubiquity deblocking defect that is difficult or not deblocking is easily caused in using.
The present invention solves this technical problem adopted technical scheme: a kind of well packer capable of flushing well realizing down-hole secondary and set, and comprises well-flushing mechanism, sealing mechanism, retaining mechanism, setting mechanism reconciliation sealing mechanism, described well-flushing mechanism comprises top connection, top cover, flushing valve and sealing ring I, top cover is installed at top connection step place, and top connection has liquid injection port I, top cover and top connection form the hydraulic cavities of flushing valve, top connection lower end is threaded with inner central tube, and sealing ring I is placed in the middle side of flushing valve Internal and external cycle, described sealing mechanism comprises exterior central tube, three packing elements, two spacer rings and joint rings, exterior central tube upper end is threaded with top cover, three packing elements are separated by two spacer rings and are arranged on above exterior central tube respectively, on middle side and position, three, below, O RunddichtringO is embedded with in joint ring, sealing ring is arranged on the above-mentioned packing element lower end be arranged on below exterior central tube, and the step block connected by exterior central tube is fixed, described retaining mechanism comprises slip spider, distinguish internal slip and lock sleeve, and slip spider is arranged on inner central tube, and distinguish internal slip is arranged in slip spider, on lock sleeve with the tooth of falling gingival cyst of mucous gland in the newborn, with profile of tooth on distinguish internal slip, can closely fasten, described setting mechanism mainly comprises upper piston, lower piston, valve seat and set valve, set on valve and be provided with inlet, set valve and comprise again valve cover, valve support, valve switch, Compress Spring and two sealing rings II, upper piston is provided with at the step place of connector, corresponding connector herein has liquid injection port II, connector lower ends and valve seat are with being threaded, the top of the connecting thread of connector has liquid injection port III, upper piston connects valve cover by casing coupling, the upper end of lower piston leans the lower end at casing coupling, the lower end of lower piston and valve seat form the hydraulic cavities of lower piston, between valve cover and inner sleeve, valve seat is installed, setting valve is arranged on valve seat, valve seat has aperture and inner sleeve forms fluid course, inner sleeve lower end connects lower contact, valve support installing is in valve seat, valve switch and Compress Spring are placed on valve support respectively, Compress Spring is positioned on valve seat, described solution sealing mechanism is deblocking sleeve, and it is arranged on the upper end of connector.
Above-mentioned a kind of well packer capable of flushing well realizing down-hole secondary and set, described top, middle side and below, the orientation under upper, the neutralization of just corresponding accompanying drawing 2 drawing.
Above-mentioned a kind of well packer capable of flushing well realizing down-hole secondary and set, described deblocking sleeve is the circular sleeve of band inner conical surface.
Above-mentioned a kind of well packer capable of flushing well realizing down-hole secondary and set, wherein involved component are by commercially available or obtain by the fabrication techniques that those skilled in the art grasp, and the installation between all component and method of attachment are all common methods that those skilled in the art grasp.
The invention has the beneficial effects as follows: compared with prior art, the present invention is a kind of to be realized the significant advantage of well packer capable of flushing well that down-hole secondary sets and is:
(1) be provided with in the setting mechanism in the present invention and set valve, after upper piston completes and once sets, valve cover is up, opens the inlet of valve, when outer hydraulic coupling reaches the setting value of valve switch, manage outer liquid and flow through fluid course injection lower piston hydraulic cavities, realize secondary to set, thus fluid pressure inside and outside balance tubing string, and substantially increase and set pressure, sealing effectiveness is good, extends the application life of packer;
(2) secondary setting valve in the present invention set be relative upper piston once set action, novel in structural design, can effectively apply the intrinsic fluid of oil well casing and repeatedly the fluid pressure that accumulates of well-flushing increase and set pressure, prevent the wriggling of tubing string, thus ensure the positiver sealing of packing element.
(3) solution sealing mechanism of the present invention adopts circular sleeve with inner conical surface as solution big envelope, make the compact overall structure of packer, make removing seal for packer action simple and reliable, avoid occurring because of the packer accident that deblocking does not cause oil pipe to break and effectively avoiding the accident breaking tubing string during well workover to occur, workover cost reduces, and has saved man-hour and cost of production.
Accompanying drawing explanation
Below in conjunction with drawings and Examples, the present invention is further described.
Fig. 1 is a kind of formation schematic block diagram realizing the well packer capable of flushing well that down-hole secondary sets of the present invention.
Fig. 2 be the present invention a kind of realize the well packer capable of flushing well that down-hole secondary sets partly cut open structural representation.
Fig. 3 be in ellipse circle in Fig. 1 part partly cut open structural representation.
Fig. 4 is the view that a kind of profile of tooth realizing lock sleeve in the well packer capable of flushing well that down-hole secondary sets and distinguish internal slip of the present invention fastens.
In figure, 1. top connection, 2. top cover, 3. flushing valve, 4. sealing ring I, 5. exterior central tube, 6. packing element, 7. spacer ring, 8. inner central tube, 9. joint ring, 10. slip spider, 11. distinguish internal slips, 12. deblocking sleeves, 13. lock sleeves, 14. upper pistons, 15. connectors, 16. casing couplings, 17. inner sleeves, 18. lower pistons, 19. set valve, 20. valve covers, 21. valve seats, 22. lower contacts, 23. step block, 24. valve supports, 25. valve switches, 26. Compress Springs, 27. liquid injection port I, 28. liquid injection port II, 29. inlets, 30. apertures, 31. fluid courses, 32. sealing rings II, 33. liquid injection port III.
Detailed description of the invention
Embodiment illustrated in fig. 1ly to show, a kind of well packer capable of flushing well realizing down-hole secondary and set of the present invention, comprise well-flushing mechanism, sealing mechanism, retaining mechanism, setting mechanism conciliate sealing mechanism; Described well-flushing mechanism comprises top connection, top cover, sealing ring I and flushing valve, described sealing mechanism comprises exterior central tube, three packing elements, two spacer rings and joint rings, described retaining mechanism comprises slip spider, distinguish internal slip and lock sleeve, described setting mechanism mainly comprises upper piston, lower piston, sets valve and valve seat, set valve and comprise again valve cover, sealing ring II, valve support, valve switch and Compress Spring, described solution sealing mechanism is deblocking sleeve.
Embodiment illustrated in fig. 2 for of the present invention a kind of realize that well packer capable of flushing well that down-hole secondary sets is fixed on the original state in the sleeve pipe of oil well being partly cut open structure, it shows that the arrangement of all parts in this flushing packer and connected mode are: top cover 2 is installed at top connection 1 step place, and top connection 1 has liquid injection port I 27, top cover 2 and top connection 1 form the hydraulic cavities of flushing valve 3, top connection 1 lower end is threaded with inner central tube 8, sealing ring I 4 is placed in the middle side of flushing valve 3 Internal and external cycle, exterior central tube 5 upper end is threaded with top cover 2, three packing elements 6 are separated by two spacer rings 7 and are arranged on above exterior central tube 5 respectively, on middle side and position, three, below, O RunddichtringO is embedded with in joint ring 9, sealing ring 9 is arranged on above-mentioned packing element 6 lower end be arranged on below exterior central tube, the step block 23 connected by exterior central tube 5 is fixed, slip spider 10 is arranged on inner central tube 8, distinguish internal slip 11 is arranged in slip spider 10, on lock sleeve 13 with the tooth of falling gingival cyst of mucous gland in the newborn, with profile of tooth on distinguish internal slip 11, can closely fasten, upper piston 14 is provided with at the step place of connector 15, corresponding connector 15 herein has liquid injection port II 28, connector 15 lower ends and valve seat 21 are with being threaded, liquid injection port III 33 is had above the screw thread of connector 15, upper piston 14 connects valve cover 20 by casing coupling 16, inner sleeve 17 lower end connects lower contact 22, the upper end of lower piston 18 leans on the lower end step of casing coupling 16, the lower end of lower piston 18 and valve seat 21 form the hydraulic cavities of lower piston 18, set on valve 19 and be provided with inlet 29, between valve cover 20 and inner sleeve 17, valve seat 21 is installed, setting valve 19 is arranged on valve seat 21, deblocking sleeve 12 is arranged on the upper end of connector 15.
Embodiment illustrated in fig. 3 is a kind of structure setting valve 19 and installation site thereof realizing the well packer capable of flushing well that down-hole secondary sets of the present invention, it shows to set valve 19 and overlaps except 20 except comprising the valve shown in Fig. 2, also comprise valve support 24, valve switch 25, Compress Spring 26 and two sealing rings II 32, aperture 30 and inner sleeve 17 that valve seat 21 has form fluid course 31, valve support 24 is arranged in valve seat 21, valve switch 25 and Compress Spring 26 are placed on valve support 24 respectively, Compress Spring 26 is positioned on valve seat 21, the two ends of valve seat 21 are embedded with sealing ring II 32, valve seat 21 is threaded with connector 15, the top of the connecting thread of connector 15 has liquid injection port III 33.Shown in this figure is set the state that valve 19 do not open at valve switch 25, sets valve 19 and is installed on valve seat 21.
Embodiment illustrated in fig. 4ly to show, setting in process and washing well process, on lock sleeve 13 with the tooth of falling gingival cyst of mucous gland in the newborn closely fasten with the profile of tooth of distinguish internal slip 11.
Embodiment 1
According to above-mentioned embodiment illustrated in fig. 1, embodiment illustrated in fig. 2 and embodiment illustrated in fig. 3, device becomes a kind of well packer capable of flushing well realizing down-hole secondary and set, and wherein, deblocking sleeve 12 is the circular sleeve of band inner conical surface, and flushing valve 3 adopts steel couple valve.This is a kind of, and to realize the course of work of the well packer capable of flushing well that down-hole secondary sets as follows:
Set process: the present embodiment is realized well packer capable of flushing well that down-hole secondary sets with after entering precalculated position under tubing string, build the pressure in oil pipe, highly pressurised liquid enters in the cavity between flushing valve 3 and top connection 1 via the liquid injection port I 27 in the top connection 1 of this packer, promote flushing valve 3 descending closedown well-flushing passage, continue pressurization, hydraulic pressure acts on upper piston 14 by the liquid injection port II 28 on connector 15, upper piston 14 promotes lock sleeve 13 and joint ring 9 compresses below packing element 6, this thrust continues through spacer ring 7 and acts on middle side and top packing element 6 successively, the diameter of packing element 6 is made to become large, thus packing oil pipe and casing annulus, formed thus and once set, meanwhile, upper piston 14 lower end is overlapped 20 up by the valve that casing coupling 16 connects, open the inlet 29 setting valve 19, when the setting value that the outer fluid pressure of pipe reaches valve switch 25 is the working environment height 0.5MPa than valve switch, valve switch 25 is opened, outer liquid enters fluid course 31 by the aperture 30 on valve seat 21, the liquid liquid injection port III 33 flowed through on connector 15 enters the hydraulic cavities of lower piston 18, hydraulic action is on lower piston 18, power is passed to upper piston 14 by the up promotion casing coupling 16 of lower piston 18, thus increase setting force further, the secondary realizing three packing elements 6 sets.
Washing well process: the current with pressure injecting certain pressure intensity in oil pipe, hydraulic pressure acts on flushing valve 3 via the eyelet in top cover 2, the valve body of promotion flushing valve 3 is up opens well-flushing passage, current flow to the pipe box annular space of this packer bottom via inner central tube 8 and the annular space of exterior central tube 5 and the tank of lock sleeve 13, bottom packer tubing string, enter oil pipe inner chamber again and return well head, reach the effect of anti-flushing well.
Deblocking process: above carry packer tubing string, top connection 1 drives inner central tube 8 to move upward, it is up that connector 15 promotes deblocking sleeve 12, and make top cover 2, exterior central tube 5 and distinguish internal slip 11 keep relative position constant due to the frictional force between three packing elements 6 and tube inner wall, deblocking sleeve 12 just forces distinguish internal slip 11 adduction, thus lock sleeve 13 is separated with distinguish internal slip 11, and three packing elements 6 can rebound successively, restore to the original state, deblocking completes.
Embodiment 2
Except the setting value reaching valve switch 25 when the outer fluid pressure of pipe is that other are all with embodiment 1 than outside during valve switch environment height 0.6MPa.
Embodiment 3
Except the setting value reaching valve switch 25 when the outer fluid pressure of pipe is that other are all with embodiment 1 than outside during valve switch environment height 0.7MPa.
Claims (2)
1. realize the well packer capable of flushing well that down-hole secondary sets, it is characterized in that: comprise well-flushing mechanism, sealing mechanism, retaining mechanism, setting mechanism reconciliation sealing mechanism, described well-flushing mechanism comprises top connection, top cover, flushing valve and sealing ring I, top cover is installed at top connection step place, and top connection has liquid injection port I, top cover and top connection form the hydraulic cavities of flushing valve, top connection lower end is threaded with inner central tube, and sealing ring I is placed in the middle side of flushing valve Internal and external cycle, described sealing mechanism comprises exterior central tube, three packing elements, two spacer rings and joint rings, exterior central tube upper end is threaded with top cover, three packing elements are separated by two spacer rings and are arranged on above exterior central tube respectively, on middle side and position, three, below, O RunddichtringO is embedded with in joint ring, sealing ring is arranged on the above-mentioned packing element lower end be arranged on below exterior central tube, and the step block connected by exterior central tube is fixed, described retaining mechanism comprises slip spider, distinguish internal slip and lock sleeve, and slip spider is arranged on inner central tube, and distinguish internal slip is arranged in slip spider, on lock sleeve with the tooth of falling gingival cyst of mucous gland in the newborn, with profile of tooth on distinguish internal slip, can closely fasten, described setting mechanism mainly comprises upper piston, lower piston, valve seat and set valve, set on valve and be provided with inlet, set valve and comprise again valve cover, valve support, valve switch, Compress Spring and two sealing rings II, upper piston is provided with at the step place of connector, corresponding connector herein has liquid injection port II, connector lower ends and valve seat are with being threaded, the top of the connecting thread of connector has liquid injection port III, upper piston connects valve cover by casing coupling, the upper end of lower piston leans the lower end at casing coupling, the lower end of lower piston and valve seat form the hydraulic cavities of lower piston, between valve cover and inner sleeve, valve seat is installed, setting valve is arranged on valve seat, valve seat has aperture and inner sleeve forms fluid course, inner sleeve lower end connects lower contact, valve support installing is in valve seat, valve switch and Compress Spring are placed on valve support respectively, Compress Spring is positioned on valve seat, described solution sealing mechanism is deblocking sleeve, and it is arranged on the upper end of connector.
2. according to the said a kind of well packer capable of flushing well realizing down-hole secondary and set of claim 1, it is characterized in that: described deblocking sleeve is the circular sleeve of band inner conical surface.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210529974.XA CN102953706B (en) | 2012-12-10 | 2012-12-10 | Washable well packer for realizing underground secondary setting |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210529974.XA CN102953706B (en) | 2012-12-10 | 2012-12-10 | Washable well packer for realizing underground secondary setting |
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| Publication Number | Publication Date |
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| CN102953706A CN102953706A (en) | 2013-03-06 |
| CN102953706B true CN102953706B (en) | 2015-04-08 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201210529974.XA Active CN102953706B (en) | 2012-12-10 | 2012-12-10 | Washable well packer for realizing underground secondary setting |
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Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105221100B (en) * | 2015-09-21 | 2017-07-11 | 西南石油大学 | A kind of non-tubing string motion is repeatable to set deblocking packer |
| CN105781477B (en) * | 2016-03-11 | 2019-04-26 | 新疆华隆油田科技股份有限公司 | The controllable flushing packer of compression bidirectional bearing |
| CN111535775B (en) * | 2020-05-21 | 2022-08-30 | 东营市华科石油科技开发有限责任公司 | Adjustable constant pressure washable well packer |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SU604967A1 (en) * | 1974-10-04 | 1978-04-30 | Полтавское отделение Украинского научно-исследовательского геологоразведочного института | Device for cementing sections of casing columns |
| CN2432333Y (en) * | 2000-06-28 | 2001-05-30 | 曹允良 | Flushing packer |
| CN2515420Y (en) * | 2001-11-13 | 2002-10-09 | 中国石油化工股份有限公司***分公司采油二厂 | Packer |
| CN2685552Y (en) * | 2003-12-01 | 2005-03-16 | 大庆石油管理局 | Static hydraulic washable well packer |
| CN201433735Y (en) * | 2009-04-10 | 2010-03-31 | 崔朝轩 | Packer special for plugging water |
| CN202937222U (en) * | 2012-12-10 | 2013-05-15 | 河北工业大学 | Well-flushing packer capable of achieving downhole secondary setting |
-
2012
- 2012-12-10 CN CN201210529974.XA patent/CN102953706B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SU604967A1 (en) * | 1974-10-04 | 1978-04-30 | Полтавское отделение Украинского научно-исследовательского геологоразведочного института | Device for cementing sections of casing columns |
| CN2432333Y (en) * | 2000-06-28 | 2001-05-30 | 曹允良 | Flushing packer |
| CN2515420Y (en) * | 2001-11-13 | 2002-10-09 | 中国石油化工股份有限公司***分公司采油二厂 | Packer |
| CN2685552Y (en) * | 2003-12-01 | 2005-03-16 | 大庆石油管理局 | Static hydraulic washable well packer |
| CN201433735Y (en) * | 2009-04-10 | 2010-03-31 | 崔朝轩 | Packer special for plugging water |
| CN202937222U (en) * | 2012-12-10 | 2013-05-15 | 河北工业大学 | Well-flushing packer capable of achieving downhole secondary setting |
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| CN102953706A (en) | 2013-03-06 |
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Effective date of registration: 20210129 Address after: 253500 east of middle section of Wuyou street, Lingxian Economic Development Zone, Dezhou City, Shandong Province Patentee after: Dezhou horizon Petroleum Technology Co.,Ltd. Address before: 300401 Hebei University of Technology, 5304 Xiping Road, Beichen District, Tianjin Patentee before: Hebei University of Technology |