CN202047783U

CN202047783U - Open hole packer and hole opening tool mated with same for use

Info

Publication number: CN202047783U
Application number: CN2010206157333U
Authority: CN
Inventors: 陈若铭; 宁世品; 李晓军; 赵继斌
Original assignee: CNPC Xibu Drilling Engineering Co Ltd
Current assignee: CNPC Xibu Drilling Engineering Co Ltd
Priority date: 2010-11-20
Filing date: 2010-11-20
Publication date: 2011-11-23
Anticipated expiration: 2020-11-20

Abstract

The utility model relates to the technical field of packers used in well fixation and completion operation in an oil gas field, and provides an open hole packer and a hole opening tool mated with the open hole packer for use. The open hole packer comprises a base tube, an upper joint, a lower transition connecting sleeve, a lower joint and an opening sleeve, wherein the upper joint is fixedly installed at the upper part of the base tube; the lower transition connecting sleeve is fixedly arranged at the lower part of the base tube; the lower joint is fixedly arranged at the lower part of the lower transition connecting sleeve; a filling hole is arranged in the inner wall of the lower transition connecting sleeve; the opening sleeve is fixedly arranged in an inner cavity of the lower transition connecting sleeve by a spacer sleeve shearing pin; a glue tube sealing and separating device and a pressure building device are arranged outside the base tube between the upper joint and the lower transition connecting sleeve; and a hole opening tool comprises a central tube, a hanging sleeve, a clamping sleeve and a claw sleeve. For the utility model, the structure is reasonable and compact; the hole opening tool can be lifted to drive the opening sleeve to move upwards to open the filling hole, so that the glue tube sealing and separating device is compressed by the pressure building device driven by pressure liquid to seal and separate a stratum; and the utility model is characterized by being safe and reliable, simple to operate, and well adaptive to irregular well walls.

Description

Open hole packer and be mated the drilling tool of use

Technical field

The utility model relates to the packer technology field that the solid completion practice of oil gas field is used, and is a kind of open hole packer and the drilling tool that is mated use.

Background technology

In work progresss such as oilfield well completion, well workover, stimulation work, often need to use packer to sit and hang on the borehole wall and the packing stratum at present, to realize purposes such as layer and section exploitation, control water blocking water, reservoir reconstruction.The existing packer that uses has the following disadvantages in actual use: complex structure, parts are various, processing cost is high, execute-in-place complex process, instrument global reliability are low, to the bad adaptability of the irregular borehole wall.

Summary of the invention

The utility model provides a kind of open hole packer and has been mated the drilling tool of use, overcome the deficiency of above-mentioned prior art, its can effectively solve complex structure that packer that the solid completion practice of existing oil gas field uses exists, not easy to operate, reliability is low, to the problem of the bad adaptability of the irregular borehole wall.

One of the technical solution of the utility model realizes by following measure: a kind of open hole packer comprises that parent tube, top connection, following conversion connect cover, lower contact and open cover; The top of parent tube is installed with top connection, the bottom of parent tube is installed with down conversion and connects cover, the bottom that following conversion connects cover is installed with lower contact, and following conversion connects on the cover inwall pack hole, opens cover and cuts off by interstage sleeve and be fixedly mounted on down conversion and connect in the inner chamber of cover also firmly pack hole of obstruction; Top connection and down conversion connect parent tube outside between the cover be equipped with the packing element packing device and can on push the device that builds the pressure of moulding tube packing device, build the pressure chamber and be connected, the device bottom that builds the pressure with pack hole.

Be further optimization and/or improvements below to one of above-mentioned utility model technical scheme:

Above-mentioned packing element packing device can comprise short circuit, packing element, following short circuit, go up back-up ring and following back-up ring; Last short circuit, packing element and following short circuit from up to down are sleeved on the parent tube successively, and last short circuit is fixedly mounted on the top connection bottom, and following short circuit is fixed together with the device top that builds the pressure; The packing element outer upper is fixed with back-up ring, and the packing element outer lower portion is fixed with down back-up ring, forms between the last back-up ring upper inside wall and the parent tube outside and goes up fixedly annular groove, forms down fixedly annular groove between the following back-up ring lower inner wall and the parent tube outside; Upper press ring is arranged at last short circuit bottom, and upper press ring is sleeved in the fixing annular groove and the lower surface of upper press ring is pressed on the upper surface of packing element, the loam cake screw thread is arranged and be installed with the upper press cover that can fix back-up ring outside the last short circuit of upper press ring top; Following pressure ring is arranged at following short circuit top, press down ring set be contained in down in the fixing annular groove and down the upper surface of pressure ring be pressed on the lower surface of packing element, there is the lower cover screw thread in the following short circuit outside of following pressure ring below and is installed with the lower cover that can fix down back-up ring.

The above-mentioned device that builds the pressure can comprise upper sliding sleeve, low sleeve, go up cover, urceolus and following cover; The upper inside wall that following conversion connects cover has the parent tube screw thread and is fixedly mounted on the parent tube bottom by the parent tube screw thread, connect under the inwall bottom that following conversion connects cover has screw thread and by under connect screw thread and be installed with lower contact, the outer lower portion that following conversion connects cover has the lower cover screw thread and is installed with down cover, the doffing portion of covering is installed with urceolus, urceolus top is installed with cover, the inwall of urceolus and the following chamber that builds the pressure between the outside that connects cover of changing, low sleeve is installed in the chamber that builds the pressure and can moves up and down, low sleeve top is fixed with upper sliding sleeve, the top of upper sliding sleeve is sleeved on cover inside and can moves up and down, and the top of upper sliding sleeve links together with following short circuit; There is interstage sleeve lock pin screw radially in the outside, middle part that following conversion connects cover and interstage sleeve is installed and cuts off, the following conversion that pack hole is positioned at interstage sleeve lock pin screw top connects and puts, the following conversion of corresponding parent tube lower end position connects on the cover inwall positive stop lug boss, the upper surface of positive stop lug boss holds out against on the lower surface of parent tube, the following conversion of positive stop lug boss below connects on the cover inwall the non-return annular slot, there is the interstage sleeve stopper slot position of opening the corresponding interstage sleeve lock pin screw in the cover outside, the inner that interstage sleeve cuts off holds out against on the bottom surface of interstage sleeve stopper slot, the outer upper of opening cover has following lock ring draw-in groove and the under shed ring is installed, and opens on the middle part lateral surface of cover and separates annular groove; Following conversion connects the position that puts homographic solution annular groove top to be had the fixture block hole and fixture block is installed, on the low sleeve of fixture block top the unfreezing through hole is arranged, there is the fastening annular groove position of corresponding fixture block and unfreezing through hole the inner on the low sleeve, the lower end of fastening annular groove is up big and down small taper thruster face, the outer end of fixture block be positioned at the fastening annular groove and make down the conversion connect the cover and low sleeve be fixed together.

Can there be check device above-mentioned parent tube outside, and check device comprises that conversion connects cover, pawl ring and transfer changing-over cover; There is limiting stand at the inner chamber middle part that last conversion connects cover, the upward conversion on limiting stand top connects on the cover inwall to be had the short circuit connecting thread and is fixedly mounted on down the short circuit bottom by the short circuit connecting thread, the upward conversion of limiting stand bottom connects on the cover inwall to be had the ring gear screw thread and is installed with the pawl ring by the ring gear screw thread, ring gear screw thread below go up conversion connect have on the cover inwall in cover connect screw thread and connect screw thread and be installed with transfer changing-over cover by middle cover, on the lower inner wall of transfer changing-over cover the sliding sleeve retaining thread is arranged and is fixed together by sliding sleeve retaining thread and upper sliding sleeve top; Be distributed with on the parent tube of packing element middle part below crown toward the outer side the top fall latch, there is the pawl hole inside of pawl ring and is sleeved on the parent tube outside, and the ring gear latch that matches with latch is arranged on the inwall of pawl hole.

On the middle part inwall of above-mentioned low sleeve following plug ring platform can be arranged, the lower surface of following plug ring platform and following the conversion form plug chamber down between the upper surface that connects cover, following conversion connects the annular space of trapping between the cover outside and the low sleeve inwall, fill in the chamber in forming between the upper surface of following plug ring platform and the lower surface of upper sliding sleeve, the unfreezing through hole is connected with following plug chamber by the annular space of trapping; On the outside, middle part of upper sliding sleeve last plug ring platform can be arranged, form the top plug chamber between the lower surface of last plug ring platform and the upper surface of low sleeve, form chamber, plug top between the upper surface of last plug ring platform and the lower surface of last cover, form between the inwall of last cover and the outside of upper sliding sleeve and go up the cover annular space; The upper outside of low sleeve has fixing pin screw radially and stop bit is installed and cuts off, and there is the sliding sleeve stopper slot position of the corresponding fixing pin screw in the outside, bottom of upper sliding sleeve, and the inner that stop bit cuts off holds out against on the bottom surface of sliding sleeve stopper slot; There is last lock ring draw-in groove in the upper sliding sleeve outside of sliding sleeve stopper slot below and the upper shed ring is installed, and on the low sleeve inwall of last lock ring draw-in groove below the lock ring stopper slot is arranged; Radially liquid hole and axially liquid hole are arranged in the top body of last cover, radially the inner in liquid hole is communicated with last collar Kongxiang, radially the outer end in liquid hole is connected with the lower end in axial liquid hole, axial valve opening is arranged on the upper surface of last cover and ball-and-seat is installed, ball-and-seat comprises bonnet, valve spring and valve ball, axially the bottom of valve opening is connected by the upper end of up big and down small bellmouth with axial liquid hole, axially the upper inside wall of valve opening has screw thread and is installed with bonnet, axial pressure release through hole is arranged in the body of bonnet, valve spring and valve ball are installed in the valve opening, the upper end of valve spring holds out against on the lower surface of bonnet, the lower end of valve spring holds out against on valve ball top, and valve ball is sitting on the bellmouth inwall and keeps sealing.

The lower surface of above-mentioned upper press cover can be pressed on the upper surface of back-up ring, there is the ring of going up draw-in groove at the edge, upper surface of upper press ring, correspondence upward can have the loam cake spacing ring and be clamped in the ring draw-in groove in the position of ring draw-in groove on the lower surface of upper press cover, can there be radially the loam cake screw hole on the top of upper press cover and be installed with the loam cake lock-screw, there is the loam cake lock slots the corresponding radially position of loam cake screw hole, the last short circuit outside, and the inner of loam cake lock-screw holds out against in the loam cake lock slots; The upper surface of lower cover can be pressed on down on the lower surface of back-up ring, there is ring draw-in groove down at the edge, lower surface of following pressure ring, correspondence can have the lower cover spacing ring and be clamped on down in the ring draw-in groove in the position of ring draw-in groove down on the upper surface of lower cover, can there be radially the lower cover screw hole bottom of lower cover and be installed with the lower cover lock-screw, there is the lower cover lock slots the corresponding radially position of lower cover screw hole, the following short circuit outside, and the inner of lower cover lock-screw holds out against in the lower cover lock slots.

The above-mentioned short circuit of going up can pass through last fixed cover, on overlap screw admittedly, upper joint sleeve and last connected set screw are installed in the top connection, last short circuit upper outside has screw thread and is installed with fixed cover, last fixed cover bottom has directly upwards to overlap screw admittedly and be installed with overlaps screw admittedly, last short circuit and last fixed cover overlap screw lock together admittedly by last, last fixed cover upper outside has boss, there is screw thread in the outside, bottom of top connection and is installed with upper joint sleeve, on the lower inner wall of upper joint sleeve Ka Tai is arranged, the upper surface of Ka Tai is pressed on the lower surface of boss and the upper end of fixed cover is held out against on the lower surface of top connection, upwards connected set screw and be installed with the connected set screw of footpath is arranged at the upper joint sleeve bottom, and upper joint sleeve and last fixed cover are by last connected set screw lock together.

Above-mentioned going up on the plug ring platform lateral surface can have top plug platform seal groove and sealing ring is installed, have on the upper inside wall of upper sliding sleeve go up the cover groove and and the parent tube outside between form and go up the collar-shaped cavity, the lower inner wall of upper sliding sleeve forms the cover boss, on overlap and the convex platform seal groove arranged on the boss inwall and sealing ring is installed; Can have on the following plug ring platform inwall and fill in the platform seal groove down and sealing ring is installed, can there be middle seal boss in the low sleeve outside of corresponding plug ring platform position down, middle boss seal groove is arranged on the middle seal boss lateral surface and sealing ring is installed; The opening cover and seal groove can be arranged on the lateral surface on the interstage sleeve and sealing ring is installed of following lock ring draw-in groove bottom, the opening the cover outside and the interstage sleeve lower seal groove cavity can be arranged and sealing ring is installed of interstage sleeve stopper slot below; The following conversion of interstage sleeve lock pin screw below connects the cover outside can the lower sealing ring platform, the following conversion on lower sealing ring platform top connects outside the cover and forms the chamber that builds the pressure between the inwall of urceolus, ring platform seal groove can be arranged on the lower sealing ring platform lateral surface down and sealing ring is installed, following conversion connects overlaps can trap seal groove and sealing ring is installed of lower inner wall and lower contact upper outside contact position.

Two of the technical solution of the utility model realizes by following measure: a kind of drilling tool that is used with open hole packer comprises central tube, articulates cover, clamping cover and pawl cover; The outside, the middle part restraining position ring block platform of central tube, the part that central tube is positioned at the limited ring dais top forms axle journal, the part that central tube is positioned at the limited ring dais below forms down axle journal, articulate the lower surface that is sleeved on the axle journal outside and articulates cover and be pressed on the upper surface of limited ring dais, articulate the outside, cover top and connect the cover boss; There is the interstage sleeve screw thread in the following axle journal outside and is installed with the clamping cover, and the upper surface of clamping cover holds out against on the lower surface of limited ring dais, and the cutting ferrule baffle ring is arranged at the top of clamping cover, forms annular telescopic cavity between the inwall of cutting ferrule baffle ring and the outside, the bottom of limited ring dais; Articulating the outside, cover bottom has the pawl external threading and is installed with the pawl cover, the upper surface of pawl cover holds out against on the lower surface that connects the cover boss, the bottom of pawl cover is sleeved in the annular telescopic cavity and can moves up and down, circumferentially there is the distinguish groove that is no less than three at the middle part of pawl cover, on having, the outer middle side part of pawl cover between adjacent two distinguish grooves carries Ka Tai, on carry Ka Tai upper surface and lower surface be respectively the up-small and down-big top fastening station conical surface and the up big and down small low fastening station conical surface, the loop buffer groove that can hold extrusion pawl cover is arranged at the top of limited ring dais.

Be two further optimization and/or improvements below to above-mentioned utility model technical scheme:

Above-mentioned central tube upper outside can have screw thread and be installed with union, the inside of union have the union chamber and with the intracavity inter-connection of central tube, the upper inside wall in union chamber can have last tube connector screw thread, can there be following tube connector screw thread in the outside, bottom of central tube.

The utility model reasonable and compact in structure, its by on carry drilling tool and drive to open to put and move the open fill hole, pressure fluid is driven build the pressure device compression packing element packing device packing stratum, have safe and reliable, easy and simple to handle, good characteristics the compliance of the irregular borehole wall.

Description of drawings

Accompanying drawing 1 partly cuts open structural representation for the master of open hole packer of the present utility model looks.

Accompanying drawing 2 is the structure for amplifying schematic diagram on accompanying drawing 1 top.

Accompanying drawing 3 is the structure for amplifying schematic diagram at accompanying drawing 1 middle part.

Accompanying drawing 4 is the structure for amplifying schematic diagram of accompanying drawing 1 bottom.

Accompanying drawing 5 is the sectional structure schematic diagram at A-A place in the accompanying drawing 4.

Accompanying drawing 6 is the sectional structure schematic diagram at B-B place in the accompanying drawing 4.

Accompanying drawing 7 partly cuts open structural representation for the master of drilling tool of the present utility model looks.

Accompanying drawing 8 is the sectional structure schematic diagram at C-C place in the accompanying drawing 7.

Coding in the accompanying drawing is respectively: 1 is parent tube, and 2 are top connection, and 3 is that conversion connects cover down, 4 are lower contact, and 5 for opening cover, and 6 is pack hole, 7 for interstage sleeve cuts off, and 8 are the chamber that builds the pressure, and 9 is last short circuit, 10 is packing element, 11 are following short circuit, and 12 is last back-up ring, and 13 are following back-up ring, 14 is upper press cover, 15 is lower cover, and 16 is upper sliding sleeve, and 17 is low sleeve, 18 is last cover, 19 is urceolus, and 20 are following cover, and 21 is the parent tube screw thread, 22 under connect screw thread, 23 is the lower cover screw thread, and 24 is interstage sleeve lock pin screw, and 25 is positive stop lug boss, 26 is non-return ring shape draw-in groove, 27 is the interstage sleeve stopper slot, and 28 is the under shed ring, and 29 for separating annular groove, 30 is fixture block, 31 are the unfreezing through hole, and 32 are the fastening annular groove, and 33 are taper thruster face, 34 connect cover for last conversion, 35 is the pawl ring, and 36 are transfer changing-over cover, and 37 is limiting stand, 38 is the short circuit connecting thread, 39 is the ring gear screw thread, and 40 is that middle cover connects screw thread, and 41 is the sliding sleeve retaining thread, 42 for falling latch, 43 is the pawl hole, and 44 are following plug ring platform, and 45 are plug chamber down, 46 are the annular space of trapping, 47 is middle plug chamber, and 48 is last plug ring platform, and 49 is the top plug chamber, 50 are chamber, plug top, 51 is last cover annular space, and 52 is the fixing pin screw, and 53 cut off for stop bit, 54 is the sliding sleeve stopper slot, 55 for the upper shed ring, and 56 is the lock ring stopper slot, and 57 are liquid hole radially, 58 is axial liquid hole, 59 is axial valve opening, and 60 is bonnet, and 61 is valve spring, 62 is valve ball, 63 are the pressure release through hole, and 64 is last ring draw-in groove, and 65 is the loam cake spacing ring, 66 is the loam cake lock-screw, 67 for encircling draw-in groove down, and 68 is the lower cover spacing ring, and 69 is the lower cover lock-screw, 70 is last fixed cover, 71 are the last screw that overlaps admittedly, and 72 is upper joint sleeve, and 73 is last connected set screw, 74 is top plug platform seal groove, 75 is last cover boss, and 76 is the convex platform seal groove, and 77 for filling in the platform seal groove down, 78 is middle seal boss, 79 is middle boss seal groove, and 80 is seal groove on the interstage sleeve, and 81 is the interstage sleeve lower seal groove cavity, 82 is the lower sealing ring platform, 83 for encircling the platform seal groove down, and 84 for trapping seal groove, and 85 is central tube 85,86 for articulating cover, 87 are the clamping cover, and 88 is the pawl cover, and 89 is limited ring dais, 90 is last axle journal, 91 are following axle journal, and 92 for connecing the cover boss, and 93 is the cutting ferrule baffle ring, 94 is annular telescopic cavity, 95 is the distinguish groove, 96 on carry Ka Tai, 97 is the top fastening station conical surface, 98 is the low fastening station conical surface, 99 is the loop buffer groove, and 100 is union, and 101 is the union chamber, 102 is last tube connector screw thread, and 103 are following tube connector screw thread.

The specific embodiment

The utility model is not subjected to the restriction of following embodiment, can determine concrete embodiment according to the technical solution of the utility model and actual conditions.

In the utility model, for convenience of description, the description of the relative position relation of each parts all is that the Butut mode according to Figure of description is described, as: upper and lower, about etc. the position relation be what to determine according to the Butut direction of Figure of description.

Below in conjunction with embodiment and accompanying drawing the utility model is further described:

Embodiment 1: shown in accompanying drawing 1,2,3,4, this open hole packer comprises parent tube 1, top connection 2, conversion connects cover 3, lower contact 4 and opens cover 5 down; The top of parent tube 1 is installed with top connection 2, the bottom of parent tube 1 is installed with down conversion and connects cover 3, the bottom that following conversion connects cover 3 is installed with lower contact 4, following conversion connects cover has pack hole 6 on 3 inwalls, opens cover 5 and cuts off 7 by interstage sleeve and be fixedly mounted on down conversion and connect in the inner chamber of cover 3 and block firmly pack hole 6; Top connection 2 and down conversion connect parent tube 1 outside between the cover 3 be equipped with the packing element packing device and can on push the device that builds the pressure of moulding tube packing device, build the pressure chamber 8 and be connected, the device bottom that builds the pressure with pack hole 6.Opening cover 5 can cut off interstage sleeve and cut off 7 and open fill hole 6 because of carrying on the drilling tool, pressure fluid in parent tube 1 inner chamber enters the chamber 8 that builds the pressure by pack hole 6, make build the pressure device action and on push away the packing element packing device, extruding packing element packing device makes it expand the packing stratum along diametric(al), has reliable, good to the compliance of the irregular borehole wall characteristics of packing.

Can according to actual needs above-mentioned open hole packer be made further optimization and/or improvements:

Shown in accompanying drawing 2,3, the packing element packing device comprises short circuit 9, packing element 10, following short circuit 11, goes up back-up ring 12 and following back-up ring 13; Last short circuit 9, packing element 10 and following short circuit 11 from up to down are sleeved on the parent tube 1 successively, and last short circuit 9 is fixedly mounted on top connection 2 bottoms, and following short circuit 11 is fixed together with the device top that builds the pressure; Packing element 10 outer upper are fixed with back-up ring 12, and packing element 10 outer lower portion are fixed with down back-up ring 13, form between last back-up ring 12 upper inside wall and parent tube 1 outside and go up fixedly annular groove, form down fixedly annular groove between following back-up ring 13 lower inner wall and parent tube 1 outside; Upper press ring is arranged at last short circuit 9 bottoms, and upper press ring is sleeved in the fixing annular groove and the lower surface of upper press ring is pressed on the upper surface of packing element 10, and there is the loam cake screw thread in last short circuit 9 outsides of upper press ring top and is installed with the upper press cover 14 that can fix back-up ring 12; Following pressure ring is arranged at following short circuit 11 tops, press down ring set be contained in down in the fixing annular groove and down the upper surface of pressure ring be pressed on the lower surface of packing element 10, there is lower cover screw thread 23 in following short circuit 11 outsides of following pressure ring below and is installed with the lower cover 15 that can fix down back-up ring 13.Last back-up ring 12 and following back-up ring 13 are fixed as one with packing element 10, packing element 10 are had the effect of strengthening support.

Shown in accompanying drawing 3,4,5,6, the device that builds the pressure comprises upper sliding sleeve 16, low sleeve 17, goes up cover 18, urceolus 19 and following cover 20; The upper inside wall that following conversion connects cover 3 has parent tube screw thread 21 and is fixedly mounted on parent tube 1 bottom by parent tube screw thread 21, connect under the inwall bottom that following conversion connects cover 3 has screw thread 22 and by under connect screw thread 22 and be installed with lower contact 4, the outer lower portion that following conversion connects cover 3 has lower cover screw thread 23 and is installed with down cover 20, following cover 20 tops are installed with urceolus 19, urceolus 19 tops are installed with cover 18, the inwall of urceolus 19 and the following chamber 8 that builds the pressure between the outside that connects cover 3 of changing, low sleeve 17 is installed in the chamber 8 that builds the pressure and can moves up and down, low sleeve 17 tops are fixed with upper sliding sleeve 16, the top of upper sliding sleeve 16 is sleeved on cover 18 inside and can moves up and down, and the top of upper sliding sleeve 16 links together with following short circuit 11; There is interstage sleeve lock pin screw 24 radially in the outside, middle part that following conversion connects cover 3 and interstage sleeve is installed and cuts off 7, the following conversion that pack hole 6 is positioned at interstage sleeve lock pin screw 24 tops connects on the cover 3, the following conversion of corresponding parent tube 1 lower end position connects on cover 3 inwalls positive stop lug boss 25, the upper surface of positive stop lug boss 25 holds out against on the lower surface of parent tube 1, the following conversion of positive stop lug boss 25 belows connects on cover 3 inwalls non-return annular slot 26, there is interstage sleeve stopper slot 27 position of opening cover 5 outsides corresponding interstage sleeve lock pin screw 24, interstage sleeve cuts off the inner of 7 and holds out against on the bottom surface of interstage sleeve stopper slot 27, opening cover 5 outer upper has following lock ring draw-in groove and under shed ring 28 is installed, and opens to overlap on 5 the middle part lateral surface and separates annular groove 29; There is the fixture block hole position that following conversion connects homographic solution annular groove 29 tops on the cover 3 and fixture block 30 is installed, on the low sleeve 17 of fixture block 30 tops unfreezing through hole 31 is arranged, there is fastening annular groove 32 position of corresponding fixture block 30 and unfreezing through hole 31 the inners on the low sleeve 17, the lower end of fastening annular groove 32 is up big and down small taper thruster face 33, the outer end of fixture block 30 be positioned at fastening annular groove 32 and make down the conversion connect the cover 3 and low sleeve 17 be fixed together.

Shown in accompanying drawing 2,3, there is check device parent tube 1 outside, and check device comprises that conversion connects cover 34, pawl ring 35 and transfer changing-over cover 36; There is limiting stand 37 at the inner chamber middle part that last conversion connects cover 34, the upward conversion on limiting stand 37 tops connects on cover 34 inwalls to be had short circuit connecting thread 38 and is fixedly mounted on down short circuit 11 bottoms by short circuit connecting thread 38, the upward conversion of limiting stand 37 bottoms connects on cover 34 inwalls to be had ring gear screw thread 39 and is installed with pawl ring 35 by ring gear screw thread 39, ring gear screw thread 39 belows go up conversion connect have on cover 34 inwalls in cover connect screw thread 40 and connect screw thread 40 and be installed with transfer changing-over cover 36 by middle cover, sliding sleeve retaining thread 41 arranged on the lower inner wall of transfer changing-over cover 36 and be fixed together by sliding sleeve retaining thread 41 and upper sliding sleeve 16 tops; Be distributed with on the parent tube 1 of packing element 10 middle parts belows crown toward the outer side the top fall latch 42, there is pawl hole 43 inside of pawl ring 35 and is sleeved on parent tube 1 outside, and the ring gear latch that matches with latch 42 is arranged on 43 inwalls of pawl hole.Can prevent packing element 10 because of the elasticity reinstatement by check device, it can only constantly be compressed and diameter becomes big.

Shown in accompanying drawing 3,4, following plug ring platform 44 is arranged on the middle part inwall of low sleeve 17, the lower surface of following plug ring platform 44 and following the conversion are filled in chamber 45 under the formation between the upper surface that connects cover 3, following conversion connects the annular space 46 of trapping between cover 3 outsides and low sleeve 17 inwalls, plug chamber 47 in forming between the lower surface of the upper surface of following plug ring platform 44 and upper sliding sleeve 16, unfreezing through hole 31 is connected with following plug chamber 45 by the annular space 46 of trapping; On the outside, middle part of upper sliding sleeve 16 last plug ring platform 48 is arranged, form top plug chamber 49 between the upper surface of the lower surface of last plug ring platform 48 and low sleeve 17, form chamber 50, plug top between the lower surface of the upper surface of last plug ring platform 48 and last cover 18, form between the outside of the inwall of last cover 18 and upper sliding sleeve 16 and go up cover annular space 51; The upper outside of low sleeve 17 has fixing pin screw 52 radially and stop bit is installed and cuts off 53, and there is sliding sleeve stopper slot 54 position of the corresponding fixing pin screw 52 in the outside, bottom of upper sliding sleeve 16, and stop bit cuts off the inner of 53 and holds out against on the bottom surface of sliding sleeve stopper slot 54; There is last lock ring draw-in groove in the outside of the upper sliding sleeve 16 of sliding sleeve stopper slot 54 belows and upper shed ring 55 is installed, and on low sleeve 17 inwalls of last lock ring draw-in groove below lock ring stopper slot 56 is arranged; Radially liquid hole 57 and axially liquid hole 58 are arranged in the top body of last cover 18, radially the inner in liquid hole 57 is connected with last cover annular space 51, radially the outer end in liquid hole 57 is connected with the lower end in axial liquid hole 58, axial valve opening 59 is arranged on the upper surface of last cover 18 and ball-and-seat is installed, ball-and-seat comprises bonnet 60, valve spring 61 and valve ball 62, axially the bottom of valve opening 59 is connected by the upper end of up big and down small bellmouth with axial liquid hole 58, axially the upper inside wall of valve opening 59 has screw thread and is installed with bonnet 60, axial pressure release through hole 63 is arranged in the body of bonnet 60, valve spring 61 and valve ball 62 are installed in the valve opening, the upper end of valve spring 61 holds out against on the lower surface of bonnet 60, the lower end of valve spring 61 holds out against on valve ball 62 tops, and valve ball 62 is sitting on the bellmouth inwall and keeps sealing.Chamber 50, plug top by last cover annular space 51, radially liquid hole 57, axially liquid hole 58, axially valve opening 59, bellmouth and pressure release through hole 63 are connected with the ball-and-seat outside.By under fill in chamber 45, top plug chamber 49, chamber 50, plug top can be avoided moving past in the journey on low sleeve 17 and the upper sliding sleeve 16 and be stuck, and by ball-and-seat the liquid in the chamber can only unidirectionally be flowed out.

Shown in accompanying drawing 2,3, the lower surface of upper press cover 14 is pressed on the upper surface of back-up ring 12, there is the ring of going up draw-in groove 64 at the edge, upper surface of upper press ring, correspondence upward has loam cake spacing ring 65 and is clamped in the ring draw-in groove 64 in the position of ring draw-in groove 64 on the lower surface of upper press cover 14, there is radially the loam cake screw hole on the top of upper press cover 14 and is installed with loam cake lock-screw 66, last short circuit 9 outside correspondences radially have the loam cake lock slots in the position of loam cake screw hole, and the inner of loam cake lock-screw 66 holds out against in the loam cake lock slots; The upper surface of lower cover 15 is pressed on down on the lower surface of back-up ring 13, there is ring draw-in groove 67 down at the edge, lower surface of following pressure ring, correspondence has lower cover spacing ring 68 and is clamped on down in the ring draw-in groove 67 in the position of ring draw-in groove 67 down on the upper surface of lower cover 15, there is radially the lower cover screw hole bottom of lower cover 15 and is installed with lower cover lock-screw 69, following short circuit 11 outside correspondences radially have the lower cover lock slots in the position of lower cover screw hole, and the inner of lower cover lock-screw 69 holds out against in the lower cover lock slots.

As shown in Figure 2, last short circuit 9 is by last fixed cover 70, on overlap screw 71 admittedly, upper joint sleeve 72 and last connected set screw 73 are fixedly mounted in the top connection 2, last short circuit 9 upper outside have screw thread and are installed with fixed cover 70, last fixed cover 70 bottoms have directly upwards to overlap screw admittedly and be installed with overlaps screw 71 admittedly, last short circuit 9 is locked together by the last screw 71 that overlaps admittedly with last fixed cover 70, last fixed cover 70 upper outside have boss, there is screw thread in the outside, bottom of top connection 2 and is installed with upper joint sleeve 72, on the lower inner wall of upper joint sleeve 72 Ka Tai is arranged, the upper surface of Ka Tai is pressed on the lower surface of boss and the upper end of fixed cover 70 is held out against on the lower surface of top connection 2, upwards connected set screw and be installed with connected set screw 73 of footpath is arranged at upper joint sleeve 72 bottoms, and upper joint sleeve 72 and last fixed cover 70 are locked together by last connected set screw 73.By last fixed cover 70, upward overlap admittedly screw 71, upper joint sleeve 72 and last connected set screw 73 fixing go up short circuits 9 not only install convenient, and firmly reliable.

Shown in accompanying drawing 2,3,4, top plug platform seal groove 74 is arranged on last plug ring platform 48 lateral surfaces and sealing ring is installed, have on the upper inside wall of upper sliding sleeve 16 go up the cover groove and and parent tube 1 outside between form and go up the collar-shaped cavity, the lower inner wall of upper sliding sleeve 16 forms cover boss 75, on overlap and convex platform seal groove 76 arranged on boss 75 inwalls and sealing ring is installed; Have on following plug ring platform 44 inwalls and fill in platform seal groove 77 down and sealing ring is installed, there is middle seal boss 78 in corresponding low sleeve 17 outsides of plug ring platform 44 positions down, middle boss seal groove 79 is arranged and sealing ring is installed on middle seal boss 78 lateral surfaces; The cover of opening of following lock ring draw-in groove bottom has on the interstage sleeve seal groove 80 on 5 lateral surfaces and sealing ring is installed, and there is interstage sleeve lower seal groove cavity 81 in cover 5 outsides of opening of interstage sleeve stopper slot 27 belows and sealing ring is installed; The following conversion of interstage sleeve lock pin screw 24 belows connects cover 3 outsides lower sealing ring platform 82, the following conversion on lower sealing ring platform 82 tops connects and forms the chamber 8 that builds the pressure between the inwall that overlaps 3 outsides and urceolus 19, ring platform seal groove 83 is arranged on lower sealing ring platform 82 lateral surfaces down and sealing ring is installed, following conversion connects overlaps trap seal groove 84 and sealing ring is installed of 3 lower inner wall and lower contact 4 upper outside contact positions.Can make by top plug platform seal groove 74 and keep sealing between the inwall of plug ring platform 48 outsides and urceolus 19, last cover groove and go up cover boss 75 and reduced contact area and frictional force between the outside of upper sliding sleeve 16 inwalls and parent tube 1 can make by convex platform seal groove 76 that maintenance seals between the outside of cover boss 75 outsides and parent tube 1; Can make down and keep sealing between the outside of plug ring platform 44 inwalls and parent tube 1 by filling in platform seal groove 77 down, in seal boss 78 reduced contact area and frictional force between the inwall of low sleeve 17 outsides and urceolus 19, in can making by middle boss seal groove 79 between the inwall of seal boss 78 outsides and urceolus 19 maintenance seal; Make by seal groove on the interstage sleeve 80 and interstage sleeve lower seal groove cavity 81 and to open cover 5 top and the outside, bottom and connect between cover 3 inwalls with conversion down and keep sealing, keep sealing between the inwall bottom that platform seal groove 83 can make lower sealing ring platform 82 outsides and urceolus 19 by encircling down, can make down conversion connect that maintenance seals between cover 3 lower inner wall and lower contact 4 upper outside by the seal groove 84 of trapping.

Embodiment 2: shown in accompanying drawing 7,8, this drilling tool comprises central tube 85, articulate cover 86, clamping cover 87 and pawl cover 88; The outside, the middle part restraining position ring block platform 89 of central tube 85, the part that central tube 85 is positioned at limited ring dais 89 tops forms axle journal 90, the part that central tube 85 is positioned at limited ring dais 89 belows forms down axle journal 91, articulate cover 86 and be sleeved on the outside and lower surface that articulate cover 86 of axle journal 90 and be pressed on the upper surface of limited ring dais 89, articulate cover 86 upper outside and connect and overlap boss 92; There is the interstage sleeve screw thread in following axle journal 91 outsides and is installed with clamping cover 87, the upper surface of clamping cover 87 holds out against on the lower surface of limited ring dais 89, cutting ferrule baffle ring 93 is arranged at the top of clamping cover 87, forms annular telescopic cavity 94 between the outside, bottom of the inwall of cutting ferrule baffle ring 93 and limited ring dais 89; Articulating the outside, cover 86 bottoms has the pawl external threading and is installed with pawl cover 88, the upper surface of pawl cover 88 holds out against on the lower surface that connects cover boss 92, the bottom of pawl cover 88 is sleeved in the annular telescopic cavity 94 and can moves up and down, circumferentially there is the distinguish groove 95 that is no less than three at the middle part of pawl cover 88, on having, pawl cover 88 outer middle side parts between adjacent two distinguish grooves 95 carry card platform 96, on carry card platform 96 upper surface and lower surface be respectively the up-small and down-big top fastening station conical surface 97 and the up big and down small low fastening station conical surface 98, the loop buffer groove 99 that can hold extrusion pawl cover 88 is arranged at the top of limited ring dais 89.On carry card platform 96 and enter and can external diameter be diminished to distinguish groove 95 inboard contractions after running into compression when opening cover 5 inner chamber, it is passed through smoothly, after passing through, can recover external diameter, drive it and move on together thereby be stuck in the lower end of opening cover 5.

Can according to actual needs above-mentioned drilling tool be made further optimization and/or improvements:

As shown in Figure 7, central tube 85 upper outside have screw thread and are installed with union 100, the inside of union 100 have union chamber 101 and with the intracavity inter-connection of central tube 85, the upper inside wall in union chamber 101 has last tube connector screw thread 102, and there is following tube connector screw thread 103 in the outside, bottom of central tube 85.

Above technical characterictic has constituted embodiment of the present utility model, and it has stronger compliance and implementation result, can increase and decrease non-essential technical characterictic according to actual needs, satisfies the demand of different situations.

The course of work of the present utility model is: at first, open hole packer is gone into well with the completion tubular string, during operation, drilling tool is sent to the open hole packer bottom, make pawl overlap 88 outsides on carry card platform 96 and be sleeved on and open in cover 5 the inner chamber, the top fastening station conical surface 97 is positioned at the below, lower surface of opening cover 5, then, on carry drilling tool, opening cover 5 is sitting on the top fastening station conical surface 97, carry drilling tool in the continuation, on carry card platform 96 and drive to open on the cover 5 and move, interstage sleeve cuts off 7 and is cut off, open cover and move on 5 under shed ring 2 is stuck in the non-return annular slot 26, open cover 5 and be fixed on down conversion and connect in the cover 3 top inner chambers, fixture block 30 inwardly is pushed into to open by taper thruster face 33 and overlaps 5 separate in the annular groove 29 simultaneously, pipe internal pressure liquid enters and promotes successively low sleeve 17 from pack hole 6, upper sliding sleeve 16, transfer changing-over cover 36, last conversion connects on cover 34 and the following short circuit 11 and moves, and extruding packing element 10 makes its expansion; At last, last conversion connects to drive on the pawl ring 35 when moving on the cover 34 and moves, and the ring gear latch is stuck in down on the latch 42, stops pawl ring 35 to move down, and has avoided packing element 10 to reply because of elasticity.

Claims

1. an open hole packer is characterized in that comprising that parent tube, top connection, following conversion connect cover, lower contact and open cover; The top of parent tube is installed with top connection, the bottom of parent tube is installed with down conversion and connects cover, the bottom that following conversion connects cover is installed with lower contact, and following conversion connects on the cover inwall pack hole, opens cover and cuts off by interstage sleeve and be fixedly mounted on down conversion and connect in the inner chamber of cover also firmly pack hole of obstruction; Top connection and down conversion connect parent tube outside between the cover be equipped with the packing element packing device and can on push the device that builds the pressure of moulding tube packing device, build the pressure chamber and be connected, the device bottom that builds the pressure with pack hole.

2. open hole packer according to claim 1 is characterized in that the packing element packing device comprises short circuit, packing element, following short circuit, goes up back-up ring and following back-up ring; Last short circuit, packing element and following short circuit from up to down are sleeved on the parent tube successively, and last short circuit is fixedly mounted on the top connection bottom, and following short circuit is fixed together with the device top that builds the pressure; The packing element outer upper is fixed with back-up ring, and the packing element outer lower portion is fixed with down back-up ring, forms between the last back-up ring upper inside wall and the parent tube outside and goes up fixedly annular groove, forms down fixedly annular groove between the following back-up ring lower inner wall and the parent tube outside; Upper press ring is arranged at last short circuit bottom, and upper press ring is sleeved in the fixing annular groove and the lower surface of upper press ring is pressed on the upper surface of packing element, the loam cake screw thread is arranged and be installed with the upper press cover that can fix back-up ring outside the last short circuit of upper press ring top; Following pressure ring is arranged at following short circuit top, press down ring set be contained in down in the fixing annular groove and down the upper surface of pressure ring be pressed on the lower surface of packing element, there is the lower cover screw thread in the following short circuit outside of following pressure ring below and is installed with the lower cover that can fix down back-up ring.

3. open hole packer according to claim 2, the device that it is characterized in that building the pressure comprise upper sliding sleeve, low sleeve, go up cover, urceolus and following cover; The upper inside wall that following conversion connects cover has the parent tube screw thread and is fixedly mounted on the parent tube bottom by the parent tube screw thread, connect under the inwall bottom that following conversion connects cover has screw thread and by under connect screw thread and be installed with lower contact, the outer lower portion that following conversion connects cover has the lower cover screw thread and is installed with down cover, the doffing portion of covering is installed with urceolus, urceolus top is installed with cover, the inwall of urceolus and the following chamber that builds the pressure between the outside that connects cover of changing, low sleeve is installed in the chamber that builds the pressure and can moves up and down, low sleeve top is fixed with upper sliding sleeve, the top of upper sliding sleeve is sleeved on cover inside and can moves up and down, and the top of upper sliding sleeve links together with following short circuit; There is interstage sleeve lock pin screw radially in the outside, middle part that following conversion connects cover and interstage sleeve is installed and cuts off, the following conversion that pack hole is positioned at interstage sleeve lock pin screw top connects and puts, the following conversion of corresponding parent tube lower end position connects on the cover inwall positive stop lug boss, the upper surface of positive stop lug boss holds out against on the lower surface of parent tube, the following conversion of positive stop lug boss below connects on the cover inwall the non-return annular slot, there is the interstage sleeve stopper slot position of opening the corresponding interstage sleeve lock pin screw in the cover outside, the inner that interstage sleeve cuts off holds out against on the bottom surface of interstage sleeve stopper slot, the outer upper of opening cover has following lock ring draw-in groove and the under shed ring is installed, and opens on the middle part lateral surface of cover and separates annular groove; Following conversion connects the position that puts homographic solution annular groove top to be had the fixture block hole and fixture block is installed, on the low sleeve of fixture block top the unfreezing through hole is arranged, there is the fastening annular groove position of corresponding fixture block and unfreezing through hole the inner on the low sleeve, the lower end of fastening annular groove is up big and down small taper thruster face, the outer end of fixture block be positioned at the fastening annular groove and make down the conversion connect the cover and low sleeve be fixed together.

4. open hole packer according to claim 3 is characterized in that there is check device the parent tube outside, and check device comprises that conversion connects cover, pawl ring and transfer changing-over cover; There is limiting stand at the inner chamber middle part that last conversion connects cover, the upward conversion on limiting stand top connects on the cover inwall to be had the short circuit connecting thread and is fixedly mounted on down the short circuit bottom by the short circuit connecting thread, the upward conversion of limiting stand bottom connects on the cover inwall to be had the ring gear screw thread and is installed with the pawl ring by the ring gear screw thread, ring gear screw thread below go up conversion connect have on the cover inwall in cover connect screw thread and connect screw thread and be installed with transfer changing-over cover by middle cover, on the lower inner wall of transfer changing-over cover the sliding sleeve retaining thread is arranged and is fixed together by sliding sleeve retaining thread and upper sliding sleeve top; Be distributed with on the parent tube of packing element middle part below crown toward the outer side the top fall latch, there is the pawl hole inside of pawl ring and is sleeved on the parent tube outside, and the ring gear latch that matches with latch is arranged on the inwall of pawl hole.

5. open hole packer according to claim 4, it is characterized in that on the middle part inwall of low sleeve following plug ring platform being arranged, the lower surface of following plug ring platform and following the conversion form plug chamber down between the upper surface that connects cover, following conversion connects the annular space of trapping between the cover outside and the low sleeve inwall, fill in the chamber in forming between the upper surface of following plug ring platform and the lower surface of upper sliding sleeve, the unfreezing through hole is connected with following plug chamber by the annular space of trapping; On the outside, middle part of upper sliding sleeve last plug ring platform is arranged, form the top plug chamber between the lower surface of last plug ring platform and the upper surface of low sleeve, form chamber, plug top between the upper surface of last plug ring platform and the lower surface of last cover, form between the inwall of last cover and the outside of upper sliding sleeve and go up the cover annular space; The upper outside of low sleeve has fixing pin screw radially and stop bit is installed and cuts off, and there is the sliding sleeve stopper slot position of the corresponding fixing pin screw in the outside, bottom of upper sliding sleeve, and the inner that stop bit cuts off holds out against on the bottom surface of sliding sleeve stopper slot; There is last lock ring draw-in groove in the upper sliding sleeve outside of sliding sleeve stopper slot below and the upper shed ring is installed, and on the low sleeve inwall of last lock ring draw-in groove below the lock ring stopper slot is arranged; Radially liquid hole and axially liquid hole are arranged in the top body of last cover, radially the inner in liquid hole is communicated with last collar Kongxiang, radially the outer end in liquid hole is connected with the lower end in axial liquid hole, axial valve opening is arranged on the upper surface of last cover and ball-and-seat is installed, ball-and-seat comprises bonnet, valve spring and valve ball, axially the bottom of valve opening is connected by the upper end of up big and down small bellmouth with axial liquid hole, axially the upper inside wall of valve opening has screw thread and is installed with bonnet, axial pressure release through hole is arranged in the body of bonnet, valve spring and valve ball are installed in the valve opening, the upper end of valve spring holds out against on the lower surface of bonnet, the lower end of valve spring holds out against on valve ball top, and valve ball is sitting on the bellmouth inwall and keeps sealing.

6. open hole packer according to claim 5, the lower surface that it is characterized in that upper press cover is pressed on the upper surface of back-up ring, there is the ring of going up draw-in groove at the edge, upper surface of upper press ring, correspondence upward has the loam cake spacing ring and is clamped in the ring draw-in groove in the position of ring draw-in groove on the lower surface of upper press cover, there is radially the loam cake screw hole on the top of upper press cover and is installed with the loam cake lock-screw, there is the loam cake lock slots the corresponding radially position of loam cake screw hole, the last short circuit outside, and the inner of loam cake lock-screw holds out against in the loam cake lock slots; The upper surface of lower cover is pressed on down on the lower surface of back-up ring, there is ring draw-in groove down at the edge, lower surface of following pressure ring, correspondence has the lower cover spacing ring and is clamped on down in the ring draw-in groove in the position of ring draw-in groove down on the upper surface of lower cover, there is radially the lower cover screw hole bottom of lower cover and is installed with the lower cover lock-screw, there is the lower cover lock slots the corresponding radially position of lower cover screw hole, the following short circuit outside, and the inner of lower cover lock-screw holds out against in the lower cover lock slots.

7. open hole packer according to claim 6, it is characterized in that short circuit is by last fixed cover, on overlap screw admittedly, upper joint sleeve and last connected set screw are installed in the top connection, last short circuit upper outside has screw thread and is installed with fixed cover, last fixed cover bottom has directly upwards to overlap screw admittedly and be installed with overlaps screw admittedly, last short circuit and last fixed cover overlap screw lock together admittedly by last, last fixed cover upper outside has boss, there is screw thread in the outside, bottom of top connection and is installed with upper joint sleeve, on the lower inner wall of upper joint sleeve Ka Tai is arranged, the upper surface of Ka Tai is pressed on the lower surface of boss and the upper end of fixed cover is held out against on the lower surface of top connection, upwards connected set screw and be installed with the connected set screw of footpath is arranged at the upper joint sleeve bottom, and upper joint sleeve and last fixed cover are by last connected set screw lock together.

8. open hole packer according to claim 7, it is characterized in that top plug platform seal groove being arranged on the plug ring platform lateral surface and sealing ring being installed, have on the upper inside wall of upper sliding sleeve go up the cover groove and and the parent tube outside between form and go up the collar-shaped cavity, the lower inner wall of upper sliding sleeve forms the cover boss, on overlap and the convex platform seal groove arranged on the boss inwall and sealing ring is installed; Have on the following plug ring platform inwall and fill in the platform seal groove down and sealing ring is installed, there is middle seal boss in the low sleeve outside of corresponding plug ring platform position down, middle boss seal groove is arranged on the middle seal boss lateral surface and sealing ring is installed; The cover of opening of following lock ring draw-in groove bottom has on the interstage sleeve seal groove on the lateral surface and sealing ring is installed, and there is the interstage sleeve lower seal groove cavity in the opening cover outside of interstage sleeve stopper slot below and sealing ring is installed; The following conversion of interstage sleeve lock pin screw below connects the cover outside the lower sealing ring platform, the following conversion on lower sealing ring platform top connects outside the cover and forms the chamber that builds the pressure between the inwall of urceolus, ring platform seal groove is arranged on the lower sealing ring platform lateral surface down and sealing ring is installed, following conversion connects overlaps trap seal groove and sealing ring is installed of lower inner wall and lower contact upper outside contact position.

9. drilling tool that is used with claim 1 or 2 or 3 or 4 or 5 or 6 or 7 or 8 described open hole packers is characterized in that comprising central tube, articulates cover, clamping cover and pawl cover; The outside, the middle part restraining position ring block platform of central tube, the part that central tube is positioned at the limited ring dais top forms axle journal, the part that central tube is positioned at the limited ring dais below forms down axle journal, articulate the lower surface that is sleeved on the axle journal outside and articulates cover and be pressed on the upper surface of limited ring dais, articulate the outside, cover top and connect the cover boss; There is the interstage sleeve screw thread in the following axle journal outside and is installed with the clamping cover, and the upper surface of clamping cover holds out against on the lower surface of limited ring dais, and the cutting ferrule baffle ring is arranged at the top of clamping cover, forms annular telescopic cavity between the inwall of cutting ferrule baffle ring and the outside, the bottom of limited ring dais; Articulating the outside, cover bottom has the pawl external threading and is installed with the pawl cover, the upper surface of pawl cover holds out against on the lower surface that connects the cover boss, the bottom of pawl cover is sleeved in the annular telescopic cavity and can moves up and down, circumferentially there is the distinguish groove that is no less than three at the middle part of pawl cover, on having, the outer middle side part of pawl cover between adjacent two distinguish grooves carries Ka Tai, on carry Ka Tai upper surface and lower surface be respectively the up-small and down-big top fastening station conical surface and the up big and down small low fastening station conical surface, the loop buffer groove that can hold extrusion pawl cover is arranged at the top of limited ring dais.

10. drilling tool according to claim 9, it is characterized in that the central tube upper outside has screw thread and is installed with union, the inside of union have the union chamber and with the intracavity inter-connection of central tube, the upper inside wall in union chamber has last tube connector screw thread, and there is following tube connector screw thread in the outside, bottom of central tube.