CN101748984B - Automatically controlled well blowout preventer mounted in drilling column - Google Patents

Automatically controlled well blowout preventer mounted in drilling column Download PDF

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Publication number
CN101748984B
CN101748984B CN200910263415A CN200910263415A CN101748984B CN 101748984 B CN101748984 B CN 101748984B CN 200910263415 A CN200910263415 A CN 200910263415A CN 200910263415 A CN200910263415 A CN 200910263415A CN 101748984 B CN101748984 B CN 101748984B
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China
Prior art keywords
ring
slide valve
central tube
well
seat
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Expired - Fee Related
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CN200910263415A
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Chinese (zh)
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CN101748984A (en
Inventor
杨启明
刘清友
杨旭文
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Southwest Petroleum University
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Southwest Petroleum University
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Abstract

The invention relates to a well blowout preventer mounted in a drilling column and automatically controlled in a well, which is capable of automatically closing the well during the well kick or the well blowout of oil-gas fields in the process of drilling the well. The invention is capable of automatically controlling the well blowout and also unlocking the blowout preventer in time so as to ensure the continuousness, safety and reliability in the process of drilling the well. The technical scheme is: a drilling tool slide valve assembly comprises a slide valve joint, a slide valve body and a slide valve seat, one end is connected to the drilling column and the other end is connected with a well blowout preventer main body. One end of the collar of the well blowout preventer main body is connected with the slide valve joint and a central tube, the collar thereon is provided with two stepped annular grooves, a clamp spring is mounted on a piston and in contact with the inner wall of the collar, a clamp pin and a clamp pin spring are mounted in the flute of the central tube, a slip ring sealing ring is mounted in the flute of the inner wall of a slip ring, a protrusion-preventing ring is mounted at the junction of a rubber barrel and the slip ring, one end of a support ring is connected with the valve body, the other end thereof is connected with the rubber barrel and the protrusion-preventing ring to form a blowout-preventing sealing device. The invention has simple structure, reliably works, is capable of effectively preventing the well blowout, and improves technical benefit and economical benefit.

Description

Be loaded on the inherent down-hole of the drill string downhole blow-out preventer of control automatically
Technical field
The present invention relates to a kind of oil gas field that is used for when drilling process because of the down-hole well kick or blowout takes place, can accomplish the downhole blow-out preventer that the inherent down-hole of drill string is controlled automatically that is loaded on of the inside and outside pass well operations of drill string automatically.
Background technology
At present used preventer is installed on well head more in the oilfield drilling process, when violent well kick phenomenon takes place in aboveground discovery down-hole operating personnel, opens the control system and accomplishes wellhead blowout preventor and close well operations, takes place to prevent gas blowout accident.The action of this type preventer, necessary experience and the sense of responsibility that relies on operating personnel possibly prevent that just gas blowout accident from taking place.If operating personnel lack experience or the carelessness when working, fail in time to find well kick or blowout sign, serious accident will take place.Then only can accomplish the blowout prevention in the drill string and can not realize the blowout prevention of full well at the storm valve of usefulness, when therefore abnormal conditions occurring, be difficult to realize whole operations of down-hole blowout prevention in the down-hole.In addition, need the regular hour because the information of down-hole generation anomaly passes to well head through medium, this moment, down-hole annular possibly lack because of well kick produces local mud, strengthen the pressure reduction of down-hole annular, thereby had aggravated the difficulty of control blowout.
Research shows that the downhole blow-out preventer that will have automaton is installed on the drill string, moves with drill string, when violent well kick anomaly takes place in the down-hole, just can guarantee in time to shunt in a well in the down-hole, prevents the generation of gas blowout accident.When needs unlatching downhole blow-out preventer carries out normal drillng operation, through aboveground perfusion mud, just can make the preventer deblocking, and need not mention drill string, change the operation of preventer, can improve drilling efficiency greatly.
Summary of the invention
The objective of the invention is: in order to overcome the shortcoming that existing wellhead blowout preventor exists; After controlling blowout automatically; Can in time make the preventer release again, guarantee drilling process continuously, safely, reliably, the spy provides a kind of inherent down-hole of drill string downhole blow-out preventer of control automatically that is loaded on.
In order to achieve the above object, the present invention solves the technical scheme that this technical problem adopts and is: a kind of inherent down-hole of drill string downhole blow-out preventer of control automatically that is loaded on, form by drilling tool Scotch yoke and downhole blow-out preventer main body.Its architectural feature is: Scotch yoke is made up of guiding valve joint, slide valve and slide valve seat, and an end is connected on the drill string, and the other end is connected with the downhole blow-out preventer main body; The two ends of guiding valve joint are processed with tubing round thread, and there is the two-stage shaft shoulder guiding valve joint inside, make the initial installing and locating of slide valve and slide valve seat; Slide valve top is that a centre is the taper circular arc body structure of circular arc property for the taper top and the bottom, and the slide valve bottom is made up of one group of wiper block with pawl type structure, is installed on the one-level shaft shoulder in the guiding valve joint; Slide valve seat is equipped with 2~8 rubber-like elements by an annular and its periphery to be formed, and is processed with a bellmouth on the annular, its taper hole big or small with slide valve on the taper circular arc body match; The downhole blow-out preventer main body is made up of box cupling, jump ring, bayonet lock, slip ring, protrusion-dispelling ring, piston, support ring, central tube, packing element; Box cupling one end is processed with screw thread; Be connected with the central tube of guiding valve joint, on box cupling, be processed with two stepped cannelures with the preventer main body; Jump ring is installed on the piston of preventer main body, closely contacts with the box cupling inwall, and the jump ring sealing ring contacts with the box cupling sealing; Bayonet lock and bayonet lock spring are installed in the groove of preventer central tube; Slip ring, slip-ring sealed ring, protrusion-dispelling ring, support ring have constituted the blowout prevention sealing device of preventer with packing element; Slip-ring sealed ring is installed on the groove of slip ring inwall; The protrusion-dispelling ring is installed in the junction of packing element and slip ring; Support ring one end has screw thread to be connected with valve body, and the other end and packing element and protrusion-dispelling ring connect and compose the main body of blowout prevention sealing device; Central tube is the interior pipe of downhole blow-out preventer; Two ends are processed with screw thread and are connected respectively with valve body with box cupling; One ring-shaped step and two through holes are arranged in the central tube; One of them through hole communicates with piston, and another through hole communicates with packing element, and in the through hole that packing element communicates orifice plate, ball-and-seat back-moving spring and ball-and-seat is installed; Ball-and-seat top is taper, and the bottom is a cylindricality, and the bellmouth that has on upper taper and the orifice plate closely is connected; Groove on the central tube is equipped with bayonet lock and bayonet lock spring; Also be processed with 3 circular ring slots on the central tube sealing ring that seals usefulness with adjacent parts is installed; Piston one end outer wall has two cannelures that jump ring and jump ring sealing ring are installed, and this end inwall has an elongate recesses, has an aperture on the piston; The valve body two ends are processed with screw thread; One end external screw thread is connected with support ring, and internal thread is connected with central tube, has a shoulder hole on the valve body; Interior deblocking spring, the support of deblocking spring and the deblocking piston installed, valve body other end screw thread is connected with short circuit and forms the downhole blow-out preventer main body; Short circuit one end is connected with valve body, and the other end is connected with drill string.
The present invention compared with prior art, the beneficial effect that has is: (1) is simple in structure, reliable operation; (2) can prevent blowout in the down-hole automatically effectively; (3) can be installed on different well depth occasions, do with driller; (4) blowout prevention in the time of can realizing well kick can be passed through aboveground deblocking again, repeatedly uses and needn't make a trip, and has practiced thrift operating cost, has improved the comprehensive technology economic benefit.
Description of drawings
Fig. 1 is the structural assembly sketch map of the downhole blow-out preventer of automatic control of the present invention.
Fig. 2 is the structural representation of the slide valve seat 6 of this downhole blow-out preventer.
Fig. 3 is the structural representation of the slide valve 7 of this downhole blow-out preventer.
Fig. 4 initially is installed on the structural representation in the guiding valve joint 1 for slide valve seat 6 and slide valve 7.
Fig. 5 is the structural representation of the ball-and-seat assembly of this downhole blow-out preventer.
Among the figure: 1, guiding valve joint; 2, box cupling; 3, central tube sealing ring; 4, jump ring; 5, piston packing; 6, slide valve seat; 7, slide valve; 8, bayonet lock; 9, bayonet lock spring, 10, slip ring; 11, protrusion-dispelling ring; 12, piston; 13, central tube sealing ring; 14, ball-and-seat; 15, orifice plate; 16, central tube; 17, packing element; 18, support ring; 19, valve body; 20, deblocking spring; 21, jump ring; 22, the deblocking spring supports; 23, deblocking piston; 24, short circuit; 25, ball-and-seat back-moving spring; 26, slip-ring sealed ring.
The specific embodiment
Below in conjunction with accompanying drawing and embodiment the present invention is described further.
Downhole blow-out preventer is made up of drilling tool Scotch yoke and downhole blow-out preventer main body, and is as shown in Figure 1.Wherein the drilling tool Scotch yoke is made up of guiding valve joint 1, slide valve seat 6, slide valve 7, is processed with the two-stage shaft shoulder on the guiding valve joint 1, a down stroke that is used for slide valve 7 location and restriction slide valve 7.One slide valve seat 6 is installed when being used for initially connecting, is processed with bellmouth on the slide valve seat 6 top annulars, the rubber-like element of some is housed, be beneficial to closely contact with the drill string inwall at its periphery, as shown in Figure 2.Slide valve 7 tops are taper cylinders that are made up of multi-section circular arc and straight line; Be beneficial to when well kick, get into slide valve seat 6, seal with slide valve seat 6 tight contacts in the formation drill string, and the promotion slide valve seat move upward until the ring-shaped step of central tube under differential pressure action; Be beneficial to central tube and form pressure reduction up and down; Impel mud to get into packing element from first through hole on the central tube, make it the outer annular space of Expansion sealing drill string, slide valve 7 bottoms are made up of one group of wiper block with pawl type structure; To remain on the linear slide of guiding valve inner nosepiece wall and downhole blow-out preventer central tube inwall, as shown in Figure 3.The structure that slide valve seat and slide valve initially are installed in the guiding valve joint is as shown in Figure 4.
The downhole blow-out preventer main body is made up of box cupling 2, central tube sealing ring 3, jump ring 4, sealing ring 5, bayonet lock 8, bayonet lock spring 9, slip ring 10, protrusion-dispelling ring 11, piston 12, sealing ring 13, ball-and-seat 14, orifice plate 15, central tube 16, packing element 17, support ring 18, valve body 19, release spring 20, jump ring 21, release spring support 22, release piston 23, short circuit 24, ball-and-seat back-moving spring 25 and slip-ring sealed ring 26.Box cupling 2 and short circuit 24 have constituted the main body of downhole blow-out preventer with above-mentioned part, its role is to guarantee the correct connection of this each part of main body; Central tube sealing ring 3, piston packing 5 and 13 sealings and each adjacent position of central tube of central tube sealing ring; Jump ring 4 control pistons 12 begin action under the level pressure difference; Bayonet lock 8, the location when bayonet lock spring 9 assurance preventer release back pistons 12 return; Slip ring 10; Slip-ring sealed ring 26, protrusion-dispelling ring 11; Packing element 17, support ring 18 and the valve body 19 common sealings of forming downhole blow-out preventers to mineshaft annulus can servo-actuateds when wherein slip ring 10 guarantees that packing elements 17 expand; When slip-ring sealed ring 26 guarantees the slip rings motion and the positiver sealing of piston 12; The edge that the installation and the location of support ring 18 and valve body 19 assurance packing elements 17, protrusion-dispelling ring 11 have protection packing element 17 is unlikely to because of being out of shape the outstanding abnormal damage that causes, and 17 of packing elements are the main seals of annular space outside the sealed well lower drill when expanding; The ball-and-seat assembly that is installed in another through hole on the central tube is made up of ball-and-seat 14, orifice plate 15 and ball-and-seat back-moving spring 25, and orifice plate 15 plays and is unlikely to protrude in the central tube outer wall when the correct installation that guarantees ball-and-seat 14 and restriction ball-and-seat 14 move; Ball-and-seat back-moving spring 25 guarantees ball-and-seat resetting after discharging the mud release, and when ball-and-seat is not worked, forms the sealing to the central tube outer wall with orifice plate; Central tube 16 is interior pipes of downhole blow-out preventer, also is to guarantee bayonet lock 8, and bayonet lock spring 9, slide valve seat 6, central tube sealing ring 3 and 13, ball-and-seat 14, ball-and-seat back-moving spring 25 and orifice plate 15 have the pipe of definite position; The release spring of installing on the valve body 19 20, jump ring 21, release spring support 22 with common the unlock parts of position of downhole blow-out preventers of forming of release piston 23; 21 of jump rings have guaranteed the correct installation site and the movement travel that has limited release spring 20 of release spring 20.
Its operating principle is following: when the well kick anomaly took place in the down-hole, because the acute variation of down-hole pressure and flow, at first the slide valve 7 of drive installation in guiding valve joint 1 moved downward along central tube 16; Get into slide valve seat 6,, seal up down-hole annular in the drill string until closely contacting with slide valve seat 6; The interior pressure reduction up and down of drill string promotion slide valve seat 6 moves forward to central tube step place with slide valve 7 to be stopped, at this moment, because interior sealing of drill string causes building the pressure; When pressure was elevated to a certain value, this High Pressure Difference drove down-hole slurry and gets into from first aperture on the central tube 16, and drive installation piston 12 on it moves downward certain distance; Seal up ball-and-seat 14 on the one hand, promote release spring support 22 simultaneously and move downward, compression release spring 20; Promote the release piston motion, can not move again until reaching desired location, at this moment; Owing to sealed in the drill string, cause from the gap of 17 of piston 12 and packing elements, getting into preventer packing element 17 because of well kick makes the mud pressure that promotes piston 12 motions continue to increase the aperture of opening from piston 12, force packing element 17 expansions; And then seal up the outer down-hole annular of drill string; Realized sealing up simultaneously the purpose of the inside and outside annular space in down-hole, stoped the generation of the gas blowout accident that possibly cause from the down-hole, guaranteed the safety in production of drilling process effectively because of well kick.
When from the aboveground kill-job of taking measures, stoped further developing of well kick, because of the pressure of kill mud in the drill string greater than down-hole pressure; 7 times horizontal resets of slide valve, the drill string internal pressure tends to balance, at this moment; Compressed release spring 20 drives release spring support 22 and moves downward because of no pressure reduction elastic return, promotes piston 12 and moves upward; Until through the ball-and-seat position, the ball-and-seat deblocking, at this moment; Because packing element 17 inwardly moves with the ball-and-seat back-moving spring 25 that central tube 16 formed pressure reduction compress under the ball-and-seats 14, the high-pressure slurries in the packing element 17 flow out through the hole that central tube leaves from ball-and-seat 14, and packing element 17 resets; The downhole blow-out preventer deblocking, because packing element 17 and 16 pressure balances of central tube at this moment, ball-and-seat back-moving spring 25 resets; Ball-and-seat 14 motions are gone in the bellmouth of orifice plate 15, have guaranteed the sealing of ball-and-seat 14 with central tube 16 outer walls, and are as shown in Figure 5.This preventer can be realized the action of blowout prevention and deblocking in the down-hole, accomplish an operation cycle after, drilling well work can be proceeded, and needn't promote drill string, works after changing preventer again.This can improve drilling efficiency, and the possibility that has just stoped blowout to take place effectively from the down-hole.
The present invention can realize preventing blowout under the working environment of drilling well and well workover.

Claims (3)

1. one kind is loaded on the inherent down-hole of the drill string downhole blow-out preventer of control automatically; Form by drilling tool Scotch yoke and downhole blow-out preventer main body; It is characterized in that: drilling tool Scotch yoke one end is connected on the drill string; The other end is connected with the downhole blow-out preventer main body, and it is made up of guiding valve joint (1), slide valve seat (6) and slide valve (7); There is tubing round thread at the two ends of guiding valve joint (1); There is the two-stage shaft shoulder guiding valve joint (1) inside; Beginning installing and locating for slide valve (7) and slide valve seat (6); Slide valve (7) is installed on the one-level shaft shoulder in the guiding valve joint (1), is processed with bellmouth on the annular of slide valve seat (6), and its taper hole size cooperates with the taper circular arc body of slide valve (7); The downhole blow-out preventer main body is made up of box cupling (2), jump ring (4), bayonet lock (8), slip ring (10), protrusion-dispelling ring (11), piston (12), central tube (16), support ring (18), packing element (17); Box cupling (2) one ends are processed with screw thread, are connected with central tube (16) with guiding valve joint (1), and box cupling (2) is provided with two stepped cannelures; Jump ring (4) is installed in piston (12) and upward closely contacts with box cupling (2) inwall, and jump ring sealing ring (5) contacts with the box cupling sealing; Bayonet lock (8) is installed in the groove of central tube (16) with bayonet lock spring (9); Slip-ring sealed ring (26) is installed on the groove of slip ring (10) inwall; Protrusion-dispelling ring (11) is installed in the junction of packing element (17) and slip ring (10); Support ring (18) one ends have screw thread to be connected with valve body (19), and the other end and packing element (17) and protrusion-dispelling ring (11) connect and compose the blowout prevention seal body; Central tube (16) two ends have screw thread to be connected respectively with valve body (19) with box cupling (2); One annular shoulder and two through holes are arranged in the central tube (16); One of them through hole communicates with packing element (17), and orifice plate (15), ball-and-seat back-moving spring (25) and ball-and-seat (14) are installed in another through hole; Groove on the central tube (16) is equipped with bayonet lock (8) and bayonet lock spring (9), also is processed with 3 circular ring slots on the central tube sealing ring (3,13,26) is installed; Piston (12) one end outer walls have two cannelures that jump ring (4) and jump ring sealing ring (21) are installed, and this end inwall has an elongate recesses, has an aperture on the piston (12); Valve body (19) two ends are processed with screw thread; The external screw thread of one end is connected with support ring (18), and internal thread is connected with central tube (16), and valve body has a shoulder hole on (19); Interior deblocking spring (20), the support of deblocking spring (22) and the deblocking piston (23) installed; The other end screw thread of valve body (19) is connected with short circuit (24), and short circuit (24) one ends are connected with valve body (19), and the other end is connected with drill string.
2. downhole blow-out preventer according to claim 1 is characterized in that: for taper, top and the bottom are the circular arc bodily form, slide valve (7) bottom is made up of one group of wiper block with pawl type structure in the middle of slide valve (7) top; Slide valve seat (6) is formed by an annulus with at 2~8 rubber-like elements that its periphery is equipped with.
3. downhole blow-out preventer according to claim 1 is characterized in that: ball-and-seat (14) top is that taper, bottom are cylindricality, and the bellmouth that has on upper taper and the orifice plate (15) closely contacts.
CN200910263415A 2009-12-13 2009-12-13 Automatically controlled well blowout preventer mounted in drilling column Expired - Fee Related CN101748984B (en)

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CN102235158B (en) * 2011-05-26 2015-05-20 西南石油大学 Underground annular blowout preventer and assembly process thereof
CN102747981A (en) * 2012-07-25 2012-10-24 曹双勇 Self-filling type pumping assembly
CN102817575B (en) * 2012-09-05 2015-03-25 西南石油大学 Downhole blow-out preventer with automatic controlling and anchoring function
CN104775785B (en) * 2015-04-24 2017-03-29 西南石油大学 A kind of downhole blow-out preventer
CN107178336A (en) * 2017-06-05 2017-09-19 西南石油大学 A kind of outburst prevention device of packing element
CN111441739B (en) * 2020-04-30 2024-06-14 大庆宏升石油机械设备制造有限公司 Mechanical compression type tubular column switch type packer
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Publication number Priority date Publication date Assignee Title
US4478279A (en) * 1982-10-12 1984-10-23 Hydril Company Retrievable inside blowout preventer valve apparatus
CN2784580Y (en) * 2004-12-21 2006-05-31 中国石化胜利油田有限公司采油工艺研究院 Hydraulic locking packer
CN201013297Y (en) * 2007-01-22 2008-01-30 唐永强 Pump recovery well mis-pressing underbalanced pump operation environment protection spraying-proof apparatus
CN201225128Y (en) * 2008-06-04 2009-04-22 中国石油天然气股份有限公司 Novel internal blowout prevention tool
CN101514618A (en) * 2009-03-27 2009-08-26 徐红军 Casing packer

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4478279A (en) * 1982-10-12 1984-10-23 Hydril Company Retrievable inside blowout preventer valve apparatus
CN2784580Y (en) * 2004-12-21 2006-05-31 中国石化胜利油田有限公司采油工艺研究院 Hydraulic locking packer
CN201013297Y (en) * 2007-01-22 2008-01-30 唐永强 Pump recovery well mis-pressing underbalanced pump operation environment protection spraying-proof apparatus
CN201225128Y (en) * 2008-06-04 2009-04-22 中国石油天然气股份有限公司 Novel internal blowout prevention tool
CN101514618A (en) * 2009-03-27 2009-08-26 徐红军 Casing packer

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