CN202338317U - Tie-back inserting and sealing device for fracturing - Google Patents
Tie-back inserting and sealing device for fracturing Download PDFInfo
- Publication number
- CN202338317U CN202338317U CN 201120426426 CN201120426426U CN202338317U CN 202338317 U CN202338317 U CN 202338317U CN 201120426426 CN201120426426 CN 201120426426 CN 201120426426 U CN201120426426 U CN 201120426426U CN 202338317 U CN202338317 U CN 202338317U
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- inwall
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Abstract
The utility model relates to a tie-back inserting and sealing device for fracturing, which is mainly used for improving horizontal well fracturing in the development process of an oil-gas field. The tie-back inserting and sealing device comprises an upper joint, a connecting drum, an upper back cap, a wiper block, a spring group, a lower back cap, a core pipe, a sliding piston, a sealing rubber drum, a pressing ring, an upper connecting sleeve, a supporting sleeve, a lower connecting sleeve and a guide cone body. The tie-back inserting and sealing device has the advantages that since a spring-adjusting type righting mechanism is used, the smooth tie backing in an inclined-shaft section is ensured; since the sealing rubber drum is compressed by adopting the sliding piston, the effect that the higher the pressure in a string, the better the sealing property is realized; in addition, the connecting sleeves also can be connected to lengthen a sealing section, so that the sealing reliability of the tie-back device is ensured, and the problems such as sealing failure in the horizontal-well staged fracturing are solved.
Description
Technical field
The utility model relates to a kind of pressure break and inserts sealing device with tieback, is mainly used in the fractured horizontal well reforming technology in the oilfield exploitation procedure, belongs to the wellbore operations instrument that the oil gas well development is used.
Background technology
Present employed tieback assembly mainly is to use to the tieback well cementation of straight well, can not satisfy the needs of fractured horizontal well technology, aspect setting upright; The righting mechanism of present tieback assembly generally adopts fixedly wiper block design, and this kind set upright mode does not have retractility, uses and is limited to; A kind of tieback of model inserts sealing device can only adapt to a kind of sleeve pipe of model wall thickness, and can not satisfy the hole deviation requirement, in addition; At seal aspect, sealing mechanism mainly adopts rubber sealing, in case cushion rubber is hurt by pipe in the tieback insertion process; The device sealing will be lost efficacy, even smooth tieback does not cooperate requirement if sealing mechanism arrives with the tieback tube; Also be difficult to the sealing effectiveness realized, aspect the controllability of former sealing mechanism, owing to adopt rubber sealing; Making a kind of tieback insert sealing can only be used by tieback tube corresponding with it, in case in construction, tieback technology is had other requirement; When the central tube of cushion rubber is laid in replacing, will be difficult in time satisfy on-the-spot fractured horizontal well production demand.
The utility model content
The purpose of the utility model is to provide a kind of pressure break to insert sealing device with tieback; Use spring adjustable type righting mechanism, guarantee that tieback inserts sealing device and realizes smooth tieback at lower curved section, in addition; When pressing crack construction; Tieback inserts sealing can bear the tubing string inner high voltage, adopts sliding plunger compression seal packing element, and sealing can realize the tubing string internal pressure good more effect of high leakproofness more; Guarantee the reliability of this tieback assembly sealing, prevent in the horizontal well in segments pressure break, to occur problems such as seal failure.Satisfy in the horizontal well in segments pressing crack construction coupling requirement to sealing and pipe tieback tube, adaptation level well pressure break production demand, the tieback constructing operation makes things convenient for, and the sealing mechanism good sealing effect.
The utility model adopts following technical scheme; Be that a kind of pressure break is inserted sealing device with tieback; By top connection, connecting cylinder, on carry on the back cap, wiper block, groups of springs, lower back cap, core barrel, sliding plunger, cartridge, pressure ring, upper joint sleeve, support set, lower joint sleeve and guiding cone and constitute; The lower ending opening that it is characterized in that top connection is connected with the outer wall thread of connecting cylinder epimere; The outer wall of connecting cylinder hypomere is connected with the inner thread of core barrel upper end; The lower thread of core barrel connects the outer wall on the top of upper joint sleeve, and upper joint sleeve bottom outer wall and lower joint sleeve external wall of upper portion are linked together by the inner thread of support set, and the outside hole enlargement attenuate of the inwall of core barrel lower end forms the thin segment of core barrel lower end; The guiding cone is threaded on the outer wall of lower joint sleeve bottom; The outside hole enlargement attenuate of the inwall at port place of guiding cone forms the thin segment of guiding cone, and the outer wall central authorities of upper and lower adapter sleeve respectively are provided with the stripper loop of a protrusion, and the outside hole enlargement attenuate of inwall that the top of support set, bottom are two sections forms the last thin segment and the following thin segment of support set; The top of the outer wall of core barrel and middle part are provided with the step convexity; Evenly have 2～8 grooves as spring groove along core barrel outer wall circumference between the two step convexities, groups of springs is installed in the spring groove, and wiper block is the strip and block of evagination; Groups of springs is supported on inwall one side of wiper block evagination in spring groove; The upper end of wiper block is pushed down by the lower end inwall that last back of the body cap leans out, and the lower end of wiper block is pushed down by the upper end inwall that the lower back cap leans out, on carry on the back cap thread and be installed on the protruding outer wall of the top stage of core barrel outer wall; The lower back cap thread is installed on the protruding outer wall of the middle bench of core barrel outer wall; Wiper block is fixed by upper and lower back of the body cap, and wiper block is radially spacing by the inwall that upper and lower back of the body cap leans out at the core barrel outer wall, in the inboard gap of the thin segment of upper joint sleeve outer wall and core barrel lower end, in the gap of upper joint sleeve outer wall and the epimere thin segment inwall of support set, in the gap of lower joint sleeve outer wall and the hypomere thin segment inwall of support set and in the thin segment inwall gap of lower joint sleeve outer wall and the guiding cone of guiding cone upper end, all seals the installation sliding plunger; Cartridge is sleeved on a side of each sliding plunger, and the stripper loop one side compression cartridge of on upper and lower adapter sleeve outer wall, protruding through pressure ring.
The pressure break of the utility model is inserted sealing device with tieback; In top connection lower inner wall and connector external wall of upper portion threaded connection place sealing ring is housed; At connector bottom outer wall and core barrel external wall of upper portion threaded connection place sealing ring is housed, sealing ring all is housed in the contact position of sliding plunger and upper and lower adapter sleeve outer wall contact position and sliding plunger and above-mentioned each thin segment inwall.
The pressure break of the utility model is inserted sealing device with tieback, and its spring groove is 2～8 rectangular recess that core barrel axially evenly has in the circumference upper edge of core barrel outer wall; Groups of springs is installed in the spring groove, and a groups of springs is made up of 3～10 springs, and a groups of springs supports same wiper block.
The pressure ring of the utility model is ring-like lid shape, and the medial surface of pressure ring compresses cartridge during installation, and the side of the stripper loop that protrudes on the outer back side of pressure ring and the adapter sleeve outer wall offsets.
The top connection of the utility model is connected through connector with core barrel; Last back of the body cap links to each other with core barrel through screw thread respectively with the lower back cap; Go up the effect that back of the body cap and lower back cap play the control wiper block simultaneously; Wiper block makes it be in softened state through spring; Core barrel, adapter sleeve, support set all link to each other through screw thread with the guiding cone, form same section sealing mechanism by same group of sliding plunger, cartridge, pressure ring and sealing ring being in contact with one another on the adapter sleeve outer wall, and the adapter sleeve outer wall is provided with the plurality of sections sealing mechanism.
The pressure break of the utility model is inserted sealing device with tieback; Can insert the tube length degree according to the tieback sealing and require lengthening seal section length; Guarantee the reliability of seal section, as long as just can realize increasing the more requirement of multistage sealing mechanism through the quantity that increases adapter sleeve and support set.
The operating principle of the utility model; This pressure break is inserted sealing device in being lowered to process with tieback, and the active force through spring props up the wiper block inwall, and wiper block is contacted with casing wall all the time; Guaranteed that tieback of the present invention inserts sealing device and in returning slotting process, is in the smooth tieback that center condition realizes this device; Adopt spring to regulate the design of wiper block simultaneously, can make wiper block contact with casing wall all the time according to the size compression spring of casing inner diameter; The tieback of realizing a kind of model inserts the sleeve pipe that sealing adapts to the various wall thickness of model of the same race, and the tieback that this kind righting mechanism is more suitable for horizontal well and extended reach well inserts use; After the tieback construction finishes, when carrying out pressing crack construction, will bear high pressure in the tubing string; The tubing string internal pressure is transmitted to and makes its compression seal packing element on the sliding plunger; Sealing mechanism is realized sealing, and the sealing effectiveness of high more each section hermetically-sealed construction of tubing string internal pressure is good more, has guaranteed reliability of the present invention.
The utility model is simple in structure, safe and reliable, is applicable to the staged fracturing construction technology of horizontal well.
Description of drawings
Figure is the pressure break of the utility model is inserted sealing device with tieback a structure chart;
Among the figure: top connection 1, connector 2, on carry on the back cap 3, wiper block 4, groups of springs 5, lower back cap 6, core barrel 7, sliding plunger 8, cartridge 9, pressure ring 10, upper joint sleeve 11, sealing ring 12, support set 13, lower joint sleeve 14, guiding cone 15, stripper loop 16.
The specific embodiment
Embodiment one; Below in conjunction with accompanying drawing; Structure to the utility model further specifies; As shown in the figure; This pressure break is inserted sealing device with tieback; By top connection 1, connecting cylinder 2, on carry on the back cap 3, wiper block 4, groups of springs 5, lower back cap 6, core barrel 7, sliding plunger 8, cartridge 9, pressure ring 10, upper joint sleeve 11, support set 13, lower joint sleeve 14 and guiding cone 15 and constitute; The lower ending opening that it is characterized in that top connection 1 is connected with the outer wall thread of connecting cylinder 2 epimeres, and the outer wall of connecting cylinder 2 hypomeres is connected with the inner thread of core barrel 7 upper ends, the be threaded outer wall on top of upper joint sleeve 11 of the lower inner wall of core barrel 7; Upper joint sleeve 11 bottom outer walls and lower joint sleeve 14 external wall of upper portion are linked together by the inner thread of support set 13; The outside hole enlargement attenuate of the inwall of core barrel 7 lower ends forms the thin segment of core barrel 7 lower ends, and guiding cone 15 is threaded on the outer wall of lower joint sleeve 14 bottoms, and the outside hole enlargement attenuate of inwall at the port place of guiding cone 15 forms the thin segment of guiding cone 14; The outer wall central authorities of upper and lower adapter sleeve 11,14 respectively are provided with the stripper loop 16 of a protrusion; The outside hole enlargement attenuate of the inwall that the top of support set 13, bottom are two sections forms the last thin segment and the following thin segment of support set 13, and the top of the outer wall of core barrel 7 and middle part are provided with the step convexity, axially evenly has the spring groove of groove conduct between the two step convexities along core barrel 7 outer wall circumference upper edge core barrels; Groups of springs 5 is installed in the spring groove; Wiper block 4 is the strip and block of evagination, and groups of springs 5 is supported on inwall one side of wiper block 4 evaginations in spring groove, and wiper block 4 is fixed by upper and lower back of the body cap 3,6; The upper end of wiper block 4 is pushed down by the lower end inwall that last back of the body cap 3 leans out; The lower end of wiper block 4 is pushed down by the upper end inwall that lower back cap 6 leans out, on carry on the back cap 3 screw threads and be installed on the protruding outer wall of the top stage of core barrel 7 outer walls, lower back cap 6 screw threads are installed on the protruding outer wall of the middle bench of core barrel 7 outer walls; Wiper block 4 is radially spacing by the inwall that upper and lower back of the body cap 3,6 leans out at core barrel 7 outer walls; In the inboard gap of the thin segment of upper joint sleeve 11 outer walls and core barrel 7 lower ends, in the gap of upper joint sleeve 11 outer walls and the epimere thin segment inwall of support set 13, in the gap of lower joint sleeve 14 outer walls and the hypomere thin segment inwall of support set 13 and in the thin segment inwall gap of lower joint sleeve 14 outer walls and the guiding cone of guiding cone 15 upper ends, all seal installation sliding plunger 8, cartridge 9 is sleeved on a side of each sliding plunger, a side of the stripper loop 16 that pressure ring 10 protrudes on the outer wall of upper and lower adapter sleeve 11,14 and compress cartridge 9.
Above-mentioned pressure break is inserted sealing device with tieback; In top connection lower inner wall and connector external wall of upper portion threaded connection place sealing ring 12 is housed; At connector bottom outer wall and core barrel external wall of upper portion threaded connection place sealing ring 12 is housed, with the contact position of the thin segment inwall of core barrel 7, support set 13, guiding cone 15 sealing ring 12 is housed all at sliding plunger 8 and upper and lower adapter sleeve 11,14 outer wall contact positions and sliding plunger 8.
Above-mentioned pressure break is inserted sealing device with tieback, and its spring groove is for core barrel axially evenly has five rectangular recess in the circumference upper edge of core barrel 7 outer walls; A groups of springs 5 is made up of four springs, and a groups of springs supports same wiper block.
Above-mentioned pressure break is inserted sealing device with tieback, and its pressure ring 10 is ring-like lid shape, and the medial surface of pressure ring 10 compresses cartridge 9 during installation, and the side of the stripper loop 16 that protrudes on the outer back side of pressure ring 10 and the adapter sleeve outer wall offsets.
Embodiment two; This pressure break is inserted sealing device with tieback, has only the adapter sleeve of connection in core barrel 7 bottoms, does not need support set in the device overall structure; Guiding cone upper end directly is connected the bottom of adapter sleeve; So only be with an adapter sleeve, two cover sealing mechanisms can only be installed on its adapter sleeve outer wall, sealing effectiveness is relatively poor.Be only applicable to the less demanding operation of pressure.
Embodiment three; This pressure break is inserted sealing device with tieback, connects three adapter sleeve monomers in core barrel 7 bottoms, promptly on the architecture basics of embodiment one; As long as increase a cover support set and a cover adapter sleeve monomer; Add the lower joint sleeve bottom that hangs over embodiment one, the bottom connects the guiding cone again, can constitute with the pressure break of six sections sealing mechanisms of three adapter sleeves and insert sealing device with tieback.
As a same reason, also can connect more a plurality of adapter sleeves, the lengthening seal section.
The content of above-mentioned utility model and the technology contents of being contained thereof all constitute the ingredient of the utility model.This pressure break is inserted sealing device with tieback, and design spring adjustable type righting mechanism can guarantee that the tieback insertion is sealed in lower curved section and realizes smooth tieback; During pressing crack construction, tieback inserts sealing can bear the tubing string inner high voltage, adopts sliding plunger compression seal packing element sealing mechanism, can realize the tubing string internal pressure good more effect of high leakproofness more, guarantees the reliability of this tieback assembly sealing.
Claims (4)
1. a pressure break is inserted sealing device with tieback; By top connection (1), connecting cylinder (2), on carry on the back cap (3), wiper block (4), groups of springs (5), lower back cap (6), core barrel (7), sliding plunger (8), cartridge (9), pressure ring (10), upper joint sleeve (11), support set (13), lower joint sleeve (14) and guiding cone (15) and constitute; The lower ending opening that it is characterized in that top connection (1) is connected with the outer wall thread of connecting cylinder (2) epimere; The outer wall of connecting cylinder (2) hypomere is connected with the inner thread of core barrel (7) upper end; The be threaded outer wall on top of upper joint sleeve (11) of the lower inner wall of core barrel (7); Upper joint sleeve (11) bottom outer wall and lower joint sleeve (14) external wall of upper portion are linked together by the inner thread of support set (13); The outside hole enlargement attenuate of the inwall of core barrel (7) lower end forms the thin segment of core barrel (7) lower end; Guiding cone (15) is threaded on the outer wall of lower joint sleeve (14) bottom; The outside hole enlargement attenuate of the inwall at the port place of guiding cone (15) forms the thin segment of guiding cone (14); The outer wall central authorities of upper and lower adapter sleeve (11), (14) respectively are provided with the stripper loop (16) of a protrusion; The outside hole enlargement attenuate of the inwall that the top of support set (13), bottom are two sections forms the last thin segment and the following thin segment of support set (13), and the top and the middle part of the outer wall of core barrel (7) are provided with the step convexity, and core barrel axially evenly has the spring groove of groove conduct along core barrel (7) outer wall circumference upper edge between the two step convexities; Groups of springs (5) is installed in the spring groove; Wiper block (4) is the strip and block of evagination, and groups of springs (5) is supported on inwall one side of wiper block (4) evagination in spring groove, and wiper block (4) is fixing by upper and lower back of the body cap (3,6); The upper end of wiper block (4) is pushed down by the lower end inwall that last back of the body cap (3) leans out; The lower end of wiper block (4) is pushed down by the upper end inwall that lower back cap (6) leans out, on carry on the back cap (3) screw thread and be installed on the protruding outer wall of the top stage of core barrel (7) outer wall, lower back cap (6) screw thread is installed on the protruding outer wall of the middle bench of core barrel (7) outer wall; Wiper block (4) is radially spacing by the inwall that upper and lower back of the body cap (3,6) leans out at core barrel (7) outer wall; In the inboard gap of the thin segment of upper joint sleeve (11) outer wall and core barrel (7) lower end, in the gap of upper joint sleeve (11) outer wall and the epimere thin segment inwall of support set (13), in the gap of lower joint sleeve (14) outer wall and the hypomere thin segment inwall of support set (13) with lower joint sleeve (14) outer wall and guiding cone (15) on the thin segment inwall gap of guiding cone in all seal installation sliding plunger (8), cartridge (9) is sleeved on a side of each sliding plunger (8), a side of the stripper loop (16) that pressure ring (10) protrudes on the outer wall of upper and lower adapter sleeve (11,14) and compress cartridge (9).
2. pressure break as claimed in claim 1 is inserted sealing device with tieback; It is characterized in that sealing ring (12) being housed in top connection (1) lower inner wall and connector (2) external wall of upper portion threaded connection place; At connector (2) bottom outer wall and core barrel (7) external wall of upper portion threaded connection place sealing ring (12) is housed, with the contact position of the thin segment inwall of core barrel (7), support set (13), guiding cone (15) sealing ring (12) is housed all at sliding plunger (8) and upper and lower adapter sleeve (11,14) outer wall contact position and sliding plunger (8).
3. pressure break as claimed in claim 1 is inserted sealing device with tieback, it is characterized in that described spring groove axially evenly has five rectangular recess for the circumference upper edge core barrel at core barrel (7) outer wall; A groups of springs (5) is made up of four springs, and a groups of springs (5) supports same wiper block.
4. pressure break as claimed in claim 1 is inserted sealing device with tieback; It is characterized in that described pressure ring (10) is ring-like lid shape; The medial surface of pressure ring (10) compresses cartridge (9), and the side of the stripper loop (16) that protrudes on the outer back side of pressure ring (10) and the adapter sleeve outer wall offsets.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201120426426 CN202338317U (en) | 2011-11-02 | 2011-11-02 | Tie-back inserting and sealing device for fracturing |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201120426426 CN202338317U (en) | 2011-11-02 | 2011-11-02 | Tie-back inserting and sealing device for fracturing |
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| Publication Number | Publication Date |
|---|---|
| CN202338317U true CN202338317U (en) | 2012-07-18 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 201120426426 Expired - Lifetime CN202338317U (en) | 2011-11-02 | 2011-11-02 | Tie-back inserting and sealing device for fracturing |
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| CN (1) | CN202338317U (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102418492A (en) * | 2011-11-02 | 2012-04-18 | 中国石油集团渤海钻探工程有限公司 | Tie-back plug-in sealing device for horizontal well fracturing |
| CN103806888A (en) * | 2012-11-12 | 2014-05-21 | 中国石油天然气股份有限公司 | Downhole infinite level digital control fracture sliding sleeve |
| CN105064948A (en) * | 2015-07-17 | 2015-11-18 | 中国石油集团西部钻探工程有限公司 | Back-inserting cementing sealing device and back-inserting cementing method |
| CN111220478A (en) * | 2020-01-20 | 2020-06-02 | 中南大学 | High-temperature high-pressure supercritical carbon dioxide rock core cracking test device |
-
2011
- 2011-11-02 CN CN 201120426426 patent/CN202338317U/en not_active Expired - Lifetime
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102418492A (en) * | 2011-11-02 | 2012-04-18 | 中国石油集团渤海钻探工程有限公司 | Tie-back plug-in sealing device for horizontal well fracturing |
| CN103806888A (en) * | 2012-11-12 | 2014-05-21 | 中国石油天然气股份有限公司 | Downhole infinite level digital control fracture sliding sleeve |
| CN103806888B (en) * | 2012-11-12 | 2016-05-11 | 中国石油天然气股份有限公司 | Down-hole infinite series control fracturing sliding bush |
| CN105064948A (en) * | 2015-07-17 | 2015-11-18 | 中国石油集团西部钻探工程有限公司 | Back-inserting cementing sealing device and back-inserting cementing method |
| CN105064948B (en) * | 2015-07-17 | 2018-09-07 | 中国石油集团西部钻探工程有限公司 | It returns slotting well cementing sealer and returns slotting cementing method |
| CN111220478A (en) * | 2020-01-20 | 2020-06-02 | 中南大学 | High-temperature high-pressure supercritical carbon dioxide rock core cracking test device |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20210622 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: 300457 science and Technology Development Department of Bohai Drilling Engineering Co., Ltd., No. 106, Huanghai Road, Tianjin Development Zone Patentee before: CNPC Bohai Drilling Engineering Co.,Ltd. |
|
| TR01 | Transfer of patent right | ||
| CX01 | Expiry of patent term |
Granted publication date: 20120718 |
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| CX01 | Expiry of patent term |