CN105863594A - High temperature and high pressure step-by-step packing and unpacking multi-stage fracturing tubular column and application method thereof - Google Patents

Abstract

The invention provides a high temperature and high pressure step-by-step packing and unpacking multi-stage fracturing tubular column and an application method thereof. According to the fracturing tubular column, in the fracturing construction process, controllable packers and sand blasters which correspond to a target construction stage position and are used in a matched mode can be opened when ball fracturing is conducted only once, and the fracturing construction process can be simpler and more convenient; step-by-step packing of a packer at the fracturing construction stage position, non-packing of a packer at the non-construction stage position and step-by-step unpacking of a packer at the constructed stage position can be achieved, sealing performance of the packer at each stage can be effectively checked, times of repeated packing and unpacking of the packers is reduced, sealing efficiency of all the packers of the tubular column is improved, and after fracturing construction is ended, the tubular column is easy to pull out.

Description

A kind of HTHP stepped setting deblocking multistage fracturing tubing string and using method thereof

Technical field

The present invention relates to a kind of HTHP stepped setting deblocking multistage fracturing tubing string and using method thereof, be mainly used in high temperature High-pressure oil-gas well staged fracturing is constructed, and belongs to completion practice construction tool.

Background technology

In recent years, oil-gas field fracturing technology has reached its maturity, and packer mechanical delamination fracturing technique has become as raising oil The agent technology of gas field well yield, but in substantial amounts of on-the-spot pressing crack construction process, there are some problems；

1. conventional multilayer partial pressure tubular column uses multiple packers to match with multiple sand blast sliding sleeves, when a certain layer of pressing crack construction, All of packer all sets, it is impossible to effectively verifies the sealing property of every one-level packer, is easily caused and alters layer, impact Pressing crack construction effect；

2. high temperature, high-pressure well, packer repeatedly sets, unseals, and packing element sealing property reduces, and causes packer sealing not Sternly, packer service life is reduced；

3. pressing crack construction terminate the easy sand of rear instrument bury, sand card, overall tubing string trips out difficulty, causes later stage measure cannot be carried out,

These problems constrain the further development of this technology；Therefore be badly in need of providing a kind of stable performance, rational in infrastructure, Can adapt to high temperature and high pressure environment, set that deblocking is reliable, be recycled into the Oil/gas Well multistage fracturing tubing string that power is high.

Summary of the invention

In view of this, for HTHP well fracturing construction characteristic, it is an object of the invention to provide a kind of high temperature high Pressure stepped setting deblocking multistage fracturing tubing string and using method thereof, wherein the special construction design of controllable confining so that should Controllable confining to set state controlled, it is achieved that fracturing string controllable confining at different levels stepped setting, non-construction layer position can Control packer does not sets, construction layer position controllable confining gradually deblocking, it is possible to effective check every one-level controllable confining Sealing, reduce controllable confining and repeatedly set the number of times of deblocking, improve the sealing effect of all controllable confinings of tubing string Rate.

For reaching above-mentioned purpose, the technical scheme is that and be achieved in that:

A kind of HTHP stepped setting deblocking multistage fracturing tubing string, described fracturing string comprises some to setting up and down and join Controllable confining that set uses and sanding machine, described fracturing string has been sequentially connected with bottom valve, packer, some from the bottom to top To described matching used controllable confining and sanding machine, sand-proof hydraulic anchor, hydraulic safety connector, between above-mentioned each instrument Connected by oil pipe；

Be provided with in described controllable confining can relatively controllable confining main body glide inner sliding sleeve assembly, described inner sliding sleeve assembly It is connected, between described inner sliding sleeve assembly and described controllable confining main body by shear pin is fixing with between described controllable confining main body Being provided with the inlet that can open, described inlet sets space with the liquid in described controllable confining main body and connects, described Being provided with reducing ball seat in inner sliding sleeve assembly, described reducing ball seat becomes big with the downslide internal diameter of described inner sliding sleeve assembly；

Be provided with in described sanding machine can sanding machine main body glides relatively sliding sleeve tee, described sliding sleeve tee and described sanding machine Connecting by shear pin is fixing between main body, described sanding machine main body is provided with the spray can glided and open by described sliding sleeve tee Sand mouth；

Reducing ball seat before described controllable confining reducing and the internal diameter phase of the sliding sleeve tee of the sanding machine of matched use With.

In prior art, it is usually disposable all seats with packers some in the fracturing string entered under oil pipe in sleeve pipe/bore hole Envelope, when needs carry out fracturing operation to certain construction layer position, then opens the sanding machine of equivalent layer position with steel ball, but above-mentioned Packer to set the time longer, even need repeatedly to set to improve the sealing of packer, this sets process certainly will Affect the service life of packer；

The fracturing process of the fracturing string of the technique scheme of the present invention is as follows: put into correspondingly sized low in Oil/gas Well Density ball, falls on the reducing ball seat of corresponding controllable confining, then suppresses in oil pipe, then builds the pressure and cuts off shear pin, Described inner sliding sleeve assembly the most described controllable confining main body glides, reducing ball during controllable confining main body glides Seat glides therewith, and reducing ball seat internal diameter expands, meanwhile, and inner sliding sleeve assembly and the intersubjective feed liquor of controllable confining Mouth is opened, and suppresses liquid and sets in space by the liquid of inlet entrance controllable confining main body, and packing element expands then, Realization sets, and can detect the sealing of this controllable confining targetedly；

After reducing ball seat internal diameter expands, low-density ball continues traveling downwardly to the sliding sleeve tee of matching used sanding machine, and builds the pressure Cutting off shear pin, sliding sleeve tee glides, and the sand jet outlet in sanding machine main body is opened, and low-density ball and sliding sleeve tee are the most descending And be seated at the lower contact of lower packer/controllable confining, thus blocking following passage, fracturing fluid enters from sand jet outlet Corresponding interval, carries out pressing crack construction, after corresponding interval pressure break, put in the case of not termination of pumping larger-size another Low-density ball, such repeat the above steps so that fracturing string is while completing target interval pressing crack construction, and pressure break is executed Work layer position controllable confining stepped setting, non-construction layer position packer do not set, construction layer position packer gradually deblocking, Effectively reduce controllable confining set the time, it is to avoid the packing element caused because setting overlong time damages and sealing The problem declined, is conducive to extending the service life of controllable confining；

It addition, this controllable confining and sanding machine with the use of, throw a ball during pressing crack construction and just can open a certain construction layer The controllable confining of position correspondence and sanding machine, make fracturing technology simpler, convenient；

The equal yield density of the low-density ball that the present invention uses is 1.5-1.6g/cm³, the voltage endurance capability of relatively steel ball is high, and shock resistance is strong Degree height, and with its low-density, light weight a little can improve its ability moved forward under level, in pressure break After construction terminates, it is also easy to, because its density is low, the row of returning, while reducing time cost, also reduces construction risk.

During pressing crack construction, the anchor fluke of sand-proof hydraulic anchor opens and is stuck on internal surface of sleeve pipe, plays the effect of fixing tubing string；Sand control water Power anchor upper end is provided with hydraulic safety connector, and construction occurs that sand plug, sand the case of emergency tubing string such as bury when cannot trip out safely, Hydraulic safety connector is opened in pitching, and tubing string disengages at hydraulic safety connector, trips out top tubing string and implements countermeasure again.

In certain embodiments, described inner sliding sleeve assembly includes sleeve, reducing ball seat, guide cylinder, spring and end cap；

It is connected by shear pin is fixing between described sleeve with described controllable confining main body；In the middle part of described sleeve, hoop is provided with some Windowing, described reducing ball seat is some wedges, described wedge by described insertion of windowing, the periphery of described wedge with Described controllable confining main body inner wall face contact, a part for described wedge be positioned at described in window, another part is positioned at In described sleeve, described wedge is positioned at the section lower of described sleeve and is provided with inclined-plane；

Described guide cylinder is positioned at described sleeve inner, and fits with described sleeve lining, is provided with spring in described guide cylinder, The upper surface of described guide cylinder is abutted spacing by the inclined-plane of described wedge, and described end cap with described sleeve bottom inwall is Threaded, the lower surface of described guide cylinder abuts with the interior shoulder of described end cap, the bottom of described sleeve and described end The outer shoulder of lid abuts, and described spring is compressed by described end cap end face.

In certain embodiments, described controllable confining main body include top connection, packing element assembly, contact control grip assembly and Lower contact；

Described top connection seals the upper end being fixedly arranged on central tube；

The periphery of central tube is located at by described packing element assembly sealing shroud, forms liquid and sit between described packing element assembly and described central tube Envelope space；

Described contact controls grip assembly and is fixedly arranged on bottom, central tube periphery, and described contact controls to be provided with feed liquor inside grip assembly Passage；

Described inner sliding sleeve assembly is relatively fixedly arranged on contact by shear pin and controls on grip assembly, and described inner sliding sleeve assembly connects with described Being provided with the inlet that can open between touch-control grip assembly, described inlet sets space with described feed pathway and described liquid Connection；

Described lower contact seals the bottom being fixedly arranged on described contact control grip assembly.

In certain embodiments, described packing element assembly includes through upper glue tube base, packing element and lower rubber cylinder that sulfuration connects as one Seat.Packing element uses high temperature high voltage resistant elastomeric material, and forms by vulcanizing casting with lower rubber cylinder seat with the upper glue tube base of irony It is integrated, it is possible to bear 90MPa pressure reduction and 150 DEG C of high temperature；

In certain embodiments, described contact control grip assembly includes crossover sub, lock ring, contact sleeve and connecting cylinder；

Described crossover sub upper end is connected with central tube bottom outer periphery threads；

Described contact sleeve is sheathed on the periphery of described inner sliding sleeve assembly upper end, and described contact sleeve periphery is provided with the first ring recess, Described crossover sub inwall is provided with the second ring recess, and described lock ring is positioned at the lock that described first ring recess is formed with described second ring recess Determining in space, this lock ring is in order to be locked in described contact sleeve on described crossover sub；It is provided with first in described contact sleeve to enter Liquid passage, is provided with the second feed pathway in described crossover sub, described lock space is positioned at described first feed pathway and institute State between the second feed pathway, and be connected with the two；I.e. feed pathway is by the first feed pathway in contact sleeve and conversion The second feed pathway in joint is constituted；

The upper end of described connecting cylinder is adjacent with the bottom of described lower rubber cylinder seat, the upper end of described connecting cylinder and described turn The outer periphery threads of changing-over head connects, and threadeds with the upper end of described lower contact in the bottom of described connecting cylinder.This connection Cylinder controls grip assembly and lower contact in order to connect contact, and in order to the position of accessory each in limiting inner sliding sleeve assembly, this setting The position making contact control grip assembly, lower contact and inner sliding sleeve assembly is more reliable and more stable, also allows for assembling.

Wherein, described contact sleeve is slot tubular construction, and described slot is line cutting, and described first feed pathway is some institutes State the liquid-retaining volume that slot is formed；This feed pathway i.e. uses the line cutting seam of 0.1～0.2mm, prevents fracturing sand from entering Enter packing element, reduce controllable confining sand card risk, it addition, described contact sleeve periphery is provided with a plurality of slot, it is possible to make packing element Rapid expanding or fast retractile, thus realize quickly setting or unsealing.

Described inner sliding sleeve assembly includes sleeve, reducing ball seat, guide cylinder, spring and end cap；

It is connected by shear pin is fixing between described sleeve with described connecting cylinder, in the periphery, upper end of described sleeve and crossover sub Wall is tightly connected；In the middle part of described sleeve, hoop is provided with some windowing, and described reducing ball seat is some wedges, described wedge shape Block by described insertion of windowing, a part for described wedge be positioned at described in window, another part is positioned at described sleeve, Peripheral and the described connecting cylinder internal face of described wedge contacts, and described wedge is positioned at the section lower of described sleeve and sets There is inclined-plane；

Described guide cylinder is positioned at described sleeve inner, and fits with described sleeve lining, is provided with spring in described guide cylinder, The upper surface of described guide cylinder is abutted spacing by the inclined-plane of described wedge, and described end cap with described sleeve bottom inwall is Threaded, the lower surface of described guide cylinder abuts with the interior shoulder of described end cap, the bottom of described sleeve and described end Lid outer shoulder abut, during end cap is screwed into sleeve, described spring by described end cap end face pressure and by Gradually compressing, the elastic force of this spring passes to the inclined-plane of wedge bottom, i.e. wedge by guide cylinder upwards by guide cylinder Outside elastic force extruding, it addition, wedge is also by the extruding inside from connecting cylinder inwall.

Thus, at controllable confining in an initial condition, inner sliding sleeve assembly is fixed on contact by shear pin and controls on grip assembly, Some wedges in inner sliding sleeve assembly form fixing reducing ball seat, and reducing under the common effect of guide cylinder and connecting cylinder Coordinate for Elastic Sliding formula between ball seat with sleeve, effectively reduce low-density ball and put into the process impulsive force to reducing ball seat, I.e. decrease the damage to reducing ball seat of the pitching process；It addition, described shear pin is located between connecting cylinder and sleeve, cut in belonging to Nail, more reliable compared with the fixed form of outer shear pin, prevent controllable confining shear pin masterpiece outside during transport or lower tubular column Loose or dislocation occurs with lower or cut off and the situation of premature setting.

In certain embodiments, the upper end of described lower contact is connected with described connecting cylinder lower periphery thread seal, described Be provided with space between lower contact inwall and described connecting cylinder, this space in order to accommodate with inner sliding sleeve assembly glide after reducing ball seat, I.e. being snapped down to this gap when reducing ball seat, reducing ball seat is by windowing in this space of entrance, and the internal diameter of reducing ball seat becomes big, Thus steel ball can continue traveling downwardly to open the sand jet outlet of the matching used sanding machine in bottom.

In certain embodiments, described top connection is additionally provided with regulation ring, described regulation ring bottom and described packing element assembly Upper end adjacent, described regulation ring inwall with described top connection periphery for threadeding.

In certain embodiments, described packing element assembly is additionally provided with the slip gear stoping described packing element assembly hoop to slide Ring, described slip baffle ring is connected with described lower rubber cylinder seat bottom inner thread, and described slip baffle ring is positioned at described lower rubber cylinder Between seat and described crossover sub.

In certain embodiments, described lock ring surface is provided with elastic rubber layer, facilitates contact sleeve to insert in crossover sub, and Be conducive to being relatively fixed of contact sleeve and crossover sub.

In certain embodiments, the edge that described controllable confining may contact with the borehole wall is fillet design protection, The most described threaded connection place is equipped with jackscrew and is fixed, so that guarantee will not be owing to colliding with during entering under controllable confining Borehole wall abrasion rigid body and packing element structure, and the premature setting phenomenon occurred during preventing from going into the well.

It addition, the present invention also aims to protect the user of a kind of HTHP stepped setting deblocking multistage fracturing tubing string Method, including following order step:

(1) according to the reservoir situation of Oil/gas Well, controllable confining and the sanding machine of respective amount is prepared, by bottom valve, packing Device, the described matching used controllable confining of respective amount and sanding machine, sand-proof hydraulic anchor, hydraulic safety connector are at oil Assemble on pipe so that it is form fracturing string；

(2) enter under the fracturing string that will assemble in the pit shaft of Oil/gas Well, make the sandblasting of the sanding machine of every one-level fracturing string Mouth is corresponding with the Reservoir Section position in Oil/gas Well；

(3) beating hydraulic pressure in oil pipe, packer setting, each controllable confining on packer top does not sets, and can pass through at the end Valve carries out pressing crack construction to No. zero interval of the bottommost of reservoir, after No. zero interval pressing crack construction terminates, and the liquid in oil pipe State is suppressed so that this packer is still in setting state still in not termination of pumping；

(4) in Oil/gas Well, put into first order low-density ball by the pitching plug valve of well head, fall in the controlled packing of the first order On the reducing ball seat of device, because in oil pipe, fluid pressure effect then builds the pressure and cuts off shear pin, described inner sliding sleeve assembly is relatively described Contact controls grip assembly and glides, and the end cap of lower cartridge runs and stops to recess in lower contact, and now reducing ball seat comes downwards to In space between lower contact and connecting cylinder, some wedges are flared out by windowing, and reducing ball seat internal diameter expands, with This simultaneously, sleeve is opened with inlet contact inner room, suppresses liquid logical by the first feed liquor of inlet entrance contact sleeve In road, and enter via lock space in the second feed pathway of crossover sub, then eventually enter between packing element and central tube Liquid set in space, packing element expand, it is achieved set；

After reducing ball seat internal diameter expands, first order low-density ball continues traveling downwardly to the sliding sleeve tee of matching used sanding machine, And build the pressure and cut off shear pin, first order low-density ball glides together with sliding sleeve tee, and the sand jet outlet in sanding machine main body is opened, First order low-density ball continues to be snapped down in lower packer together with sliding sleeve tee, and is seated under lower packer and connects At Tou, thus blocking following passage, now bottom packer and first order controllable confining are in setting state, pressure break Liquid enters an interval from sand jet outlet, carries out pressing crack construction, and after an interval pressing crack construction terminates, the liquid in oil pipe is still Be in not termination of pumping suppresses state so that bottom this, packer and first order controllable confining are still in setting state；

(5) in Oil/gas Well, put into, by the pitching plug valve of well head, the second level low-density ball being relatively large in diameter, repeat step (4), low-density ball in the second level can in succession make second level controllable confining set and and then open the sandblasting of second level sanding machine Mouthful, second level low-density ball continues to be snapped down in the first order controllable confining of bottom together with sliding sleeve tee, and is located At the end cap of first order controllable confining sleeve, thus blocking following passage, bottom packer unseals then, the first order Controllable confining and second level controllable confining are in setting state, and fracturing fluid enters No. two intervals from sand jet outlet, presses Splitting construction, after No. two interval pressing crack constructions terminate, the liquid in oil pipe suppresses state still in not termination of pumping so that this is years old One-level packer and second level controllable confining are still in setting state；

(6) more intervals can be repeated step (5) and it is carried out pressing crack construction operation, thus complete fracturing string by While level pressing crack construction, it is achieved packer and the stepped setting of each controllable confining and gradually deblocking；Such as, the is put into After three grades of low-density balls, first order controllable confining can unseal, second level controllable confining and third level controllable confining It is in the state of setting, thus conveniently No. three intervals is carried out pressing crack construction.

Preferably, described packer is K344 packer.

The fracturing string of present invention multipotency in 5 1/2in sleeve pipes realizes point 7 grades of pressure breaks.

Relative to prior art, present invention have the advantage that the fracturing string of the present invention throws a ball when pressing crack construction Just can open matching used controllable confining corresponding to target construction layer position and sanding machine, make pressing crack construction technique simpler Single, convenient；Be capable of pressing crack construction zonal isolation device stepped setting, non-construction layer position packer does not sets, constructs Zonal isolation device gradually deblocking, it is possible to the effective sealing checking every one-level packer, reduces packer and repeatedly sets solution The number of times of envelope, improves the leakage efficiency of all packers of tubing string.

Accompanying drawing explanation

The accompanying drawing of the part constituting the present invention is used for providing a further understanding of the present invention, the schematic enforcement of the present invention Example and explanation thereof are used for explaining the present invention, are not intended that inappropriate limitation of the present invention.In the accompanying drawings:

Fig. 1 is the attachment structure schematic diagram of fracturing string described in the embodiment of the present invention；

Fig. 2 is the structural representation of controllable confining original state in the embodiment of the present invention；

Fig. 3 is the structural representation that in the embodiment of the present invention, controllable confining sets state；

Fig. 4 is that the inner sliding sleeve assembly of controllable confining in the embodiment of the present invention contacts control grip assembly non-slip-down state knot relatively Structure schematic diagram；

Fig. 5 is that the inner sliding sleeve assembly of controllable confining in the embodiment of the present invention contacts state knot after control grip assembly glides relatively Structure schematic diagram；

Fig. 6 is the close-up schematic view of Fig. 4；

Fig. 7 is the partial enlargement structural representation of Fig. 5, and schematically show controllable confining and set state and suppress liquid The flow trace of body；

Fig. 8 is the structural representation of the sleeve of controllable confining in the embodiment of the present invention；

Fig. 9 is that the A-A of Fig. 8 is to schematic cross-section.

Description of reference numerals:

A-bottom valve, B-K344 packer, C-first order controllable confining, D-first order sanding machine, the E-second level is controlled Packer, F-second level sanding machine, G-sand-proof hydraulic anchor, H-hydraulic safety connector, I-oil pipe；1-top connection, 11-adjusts Joint ring, 2-packing element assembly, the upper glue tube base of 21-, 22-packing element, 23-lower rubber cylinder seat, 24-slip baffle ring, 3-contact controls set Assembly, 31-crossover sub, 311-the second ring recess, 32-lock ring, 33-contact sleeve, 331-the first ring recess, 34-connecting cylinder, 4-inner sliding sleeve assembly, 41-sleeve, 411-windows, 42-reducing ball seat, 421-wedge, 43-guide cylinder, 44-spring, 45-end cap, 46-shear pin, 5-lower contact, 51-space, 6-central tube.

Detailed description of the invention

It should be noted that in the case of not conflicting, the embodiment in the present invention and the feature in embodiment can be mutual Combination.

In describing the invention, it is to be understood that term " " center ", " longitudinally ", " laterally ", " on ", D score, " front ", The orientation of the instruction such as " afterwards ", "left", "right", " vertically ", " level ", " top ", " end ", " interior ", " outward " or position relationship For based on orientation shown in the drawings or position relationship, it is for only for ease of the description present invention and simplifies description rather than instruction Hint indication device or element must have specific orientation, with specific azimuth configuration and operation, therefore can not manage Solve as limitation of the present invention.Additionally, term " first ", " second " etc. are only used for describing purpose, and it is not intended that refer to Show or imply relative importance or the implicit quantity indicating indicated technical characteristic.Thus, define " first ", " Two " feature etc. can express or implicitly include one or more this feature.In describing the invention, unless Being otherwise noted, " multiple " are meant that two or more.

In describing the invention, it should be noted that unless otherwise clearly defined and limited, term " is installed ", " phase Even ", " connection " should be interpreted broadly, for example, it may be fixing connection, it is also possible to be to removably connect, or connect integratedly Connect；Can be to be mechanically connected, it is also possible to be electrical connection；Can be to be joined directly together, it is also possible to by the indirect phase of intermediary Even, can be the connection of two element internals.For the ordinary skill in the art, concrete condition can be passed through Understand above-mentioned term concrete meaning in the present invention.

In describing the invention, term " original state " refers to the off working state of packer or controllable confining.

Bottom valve, K344 packer, sanding machine, sand-proof hydraulic anchor, hydraulic safety connector and the oil pipe that the present invention relates to are Conventional accessory in Completion Operations, commercially available.

Describe the present invention below with reference to the accompanying drawings and in conjunction with the embodiments in detail.

The specific embodiment of the present invention:

Embodiment 1

As shown in figs 1-9, a kind of HTHP stepped setting deblocking multistage fracturing tubing string of the present embodiment, described pressure break pipe Post comprises some to setting up and down and matching used controllable confining and sanding machine, and described fracturing string is the most sequentially Connect have bottom valve A, packer B, some to described matching used controllable confining and sanding machine, sand-proof hydraulic anchor G, Hydraulic safety connector H, is connected by oil pipe I between above-mentioned each instrument；

Be provided with in described controllable confining can relatively controllable confining main body glide inner sliding sleeve assembly 4, described inner sliding sleeve group It is connected by shear pin 46 is fixing between part 4 with described controllable confining main body, described inner sliding sleeve assembly 4 and described controlled packing Being provided with the inlet that can open between device main body, described inlet and the liquid in described controllable confining main body set space even Logical, it is provided with reducing ball seat 42 in described inner sliding sleeve assembly, in the downslide with described inner sliding sleeve assembly 4 of the described reducing ball seat 42 Footpath becomes big；

Be provided with in described sanding machine can sanding machine main body glides relatively sliding sleeve tee, described sliding sleeve tee and described sanding machine Connecting by shear pin is fixing between main body, described sanding machine main body is provided with the spray can glided and open by described sliding sleeve tee Sand mouth；

Reducing ball seat before described controllable confining reducing and the internal diameter phase of the sliding sleeve tee of the sanding machine of matched use With.

The using method of the fracturing string of the present embodiment is as follows:

(1) according to the reservoir situation of Oil/gas Well, prepare the controllable confining of respective amount and sanding machine, by bottom valve A, K344 packer B, the described matching used controllable confining of respective amount and sanding machine, sand-proof hydraulic anchor G, hydraulic pressure Safety joint H assembles on oil pipe I so that it is form fracturing string；

(2) enter under the fracturing string that will assemble in the pit shaft of Oil/gas Well, make the sandblasting of the sanding machine of every one-level fracturing string Mouth is corresponding with the Reservoir Section position in Oil/gas Well；

(3) beating hydraulic pressure in oil pipe I, K344 packer B sets, each controlled packing on K344 packer B top Device does not sets, and by bottom valve, No. zero interval of the bottommost of reservoir can be carried out pressing crack construction, and No. zero interval pressing crack construction is tied Shu Hou, the liquid in oil pipe I suppresses state still in not termination of pumping so that this K344 packer B is still in setting state；

(4) in Oil/gas Well, put into first order low-density ball by the pitching plug valve of well head, fall in the controlled packing of the first order On the reducing ball seat 42 of device C, because in oil pipe, fluid pressure effect then builds the pressure and cuts off shear pin 46, described inner sliding sleeve assembly 4 The most described controllable confining main body glides, and during controllable confining main body glides, reducing ball seat 42 glides therewith, And reducing ball seat 42 internal diameter expands, meanwhile, inner sliding sleeve assembly 4 inlet intersubjective with controllable confining is opened, Suppressing liquid and set in space by the liquid of inlet entrance controllable confining main body, packing element expands then, it is achieved set, And the sealing of this controllable confining can be detected targetedly；

After reducing ball seat 42 internal diameter expands, first order low-density ball continues traveling downwardly to matching used first order sanding machine D's On sliding sleeve tee, and building the pressure and cut off shear pin, first order low-density ball glides together with sliding sleeve tee, in sanding machine main body Sand jet outlet open, first order low-density ball slides in the K344 packer B of bottom under continuing together with sliding sleeve tee, And be seated at the lower contact of bottom K344 packer, thus block following passage, now bottom K344 packer B and First order controllable confining C is in setting state, and fracturing fluid enters an interval from sand jet outlet, carries out pressing crack construction, After a number interval pressing crack construction terminates, the liquid in oil pipe I suppresses state still in not termination of pumping so that K344 bottom this Packer B and first order controllable confining C is still in setting state；

(5) in Oil/gas Well, put into, by the pitching plug valve of well head, the second level low-density ball being relatively large in diameter, repeat step (4), low-density ball in the second level can in succession make second level controllable confining E set and and then open second level sanding machine F's Sand jet outlet, second level low-density ball slides in the first order controllable confining C of bottom under continuing together with sliding sleeve tee, and sits Falling at first order controllable confining C lower contact, thus block following passage, bottom K344 packer B solves then Envelope, first order controllable confining C and second level controllable confining E is in setting state, and fracturing fluid enters two from sand jet outlet Number interval, carries out pressing crack construction, liquid the beating still in not termination of pumping after No. two interval pressing crack constructions terminate, in oil pipe I Pressure condition so that this first order packer C and second level controllable confining E is still in setting state；

(6) more intervals can be repeated step (5) and it is carried out pressing crack construction operation, thus complete fracturing string by While level pressing crack construction, it is achieved packer and the stepped setting of each controllable confining and gradually deblocking.

Embodiment 2

As shown in figs 1-9, a kind of HTHP stepped setting deblocking multistage fracturing tubing string of the present embodiment, described pressure break pipe Post comprises some to setting up and down and matching used controllable confining and sanding machine, and described fracturing string is the most sequentially Connect have bottom valve A, packer B, some to described matching used controllable confining and sanding machine, sand-proof hydraulic anchor G, Hydraulic safety connector H, is connected by oil pipe I between above-mentioned each instrument；

Described controllable confining include top connection 1, packing element assembly 2, contact control grip assembly 3, inner sliding sleeve assembly 4 and under Joint 5；

Described top connection 1 seals the upper end being fixedly arranged on central tube 6；

Described packing element assembly 2 sealing shroud is located at the periphery of central tube 6, shape between described packing element assembly 2 and described central tube 6 Liquid is become to set space；

Described contact controls grip assembly 3 and is fixedly arranged on the peripheral bottom of central tube 6, and described contact controls grip assembly 3 inside and sets There is feed pathway；

Described inner sliding sleeve assembly 4 is relatively fixedly arranged on contact by shear pin 46 and controls on grip assembly 3, described inner sliding sleeve assembly 4 The inlet that can open, described inlet and described feed pathway and described liquid it is provided with between control grip assembly 3 with described contact Body sets space connection；

Described inner sliding sleeve assembly 4 includes sleeve 41, reducing ball seat 42, guide cylinder 43, spring 44 and end cap 45；

Described sleeve 41 connects by shear pin 46 is fixing between control grip assembly 3 with described contact, the upper end of described sleeve 41 Portion is peripheral controls the connection of grip assembly 3 inner wall sealing with contacting；In the middle part of described sleeve 41, hoop is provided with 6 and windows 411, institute Stating reducing ball seat 42 is 6 wedges 421, and described wedge 421 is by described 411 insertions of windowing, described wedge 421 A part be positioned at described in window 411, another part is positioned at described sleeve 41, the periphery of described wedge 421 with Described connecting cylinder 34 internal face contacts, and described wedge 421 is positioned at the section lower of described sleeve 41 and is provided with inclined-plane；

It is internal that described guide cylinder 43 is positioned at described sleeve 41, and fits with described sleeve 41 inwall, described guide cylinder 43 Inside being provided with spring 44, the upper surface of described guide cylinder 43 is abutted spacing by the inclined-plane of described wedge 421, described end cap 45 with described sleeve 41 bottom inwall for threadeding, the interior platform of the lower surface of described guide cylinder 43 and described end cap 45 Shoulder abuts, and the bottom of described sleeve 41 abuts with the outer shoulder of described end cap 45, and described spring 44 is by described end cap The compression of end face.

Described lower contact 5 seals the bottom being fixedly arranged on described contact control grip assembly 3, and described lower contact 5 inwall is provided with Space 51, after the most described contact of described inner sliding sleeve assembly 4 controls grip assembly 3 downslide, described wedge 421 is positioned at In described space 51.

Be provided with in described sanding machine can sanding machine main body glides relatively sliding sleeve tee, described sliding sleeve tee and described sanding machine Connecting by shear pin is fixing between main body, described sanding machine main body is provided with the spray can glided and open by described sliding sleeve tee Sand mouth；

Reducing ball seat before described controllable confining reducing and the internal diameter phase of the sliding sleeve tee of the sanding machine of matched use With.

The assembling process of the controllable confining of the present embodiment of the controllable confining of the present embodiment is as follows:

(1) top connection 1 is fixed on bench vice；

(2) installing central tube 6, threaded with central tube 6 upper end in top connection 1 bottom, top connection 1 and center Sealed by sealing ring between pipe 6；

(3) installing packing element assembly 2, the packing element assembly 2 after sulfuration is sleeved on the periphery of central tube 6, packing element assembly 2 with Sealed by sealing ring between top connection 1；

(4) installing contact and control grip assembly 3, contact controls grip assembly 3 upper end and threadeds with central tube 6 bottom, Contact controls to be sealed by sealing ring between grip assembly 3 and central tube 6；Contact controls grip assembly 3 bottom and lower contact 5 Upper end is threaded fixing, and contact controls to be sealed by sealing ring between grip assembly 3 and lower contact 5；

(5) assemble inner sliding sleeve assembly 4,6 wedges 421 are inserted 6 of sleeve 41 correspondence and windows in 411； Being directed to cylinder 43 and insert sleeve 41, the upper end of guide cylinder 43 abuts with the inclined-plane of wedge 421, is placed in by spring 44 In guide cylinder 43, end cap 45 is threadeded with sleeve 41 inwall bottom, and is fixed by jackscrew, at end cap 45 screw thread During being screwed into sleeve 41, end cap 45 end face compression spring 44, the elastic force of this spring 44 is entered by guide cylinder 43 And prop up the inclined-plane of wedge 421；Shear pin 46 is fixed in some fixing holes that sleeve 41 periphery is arranged circumferentially；

(6) the inner sliding sleeve assembly 4 that installation steps (5) assemble, inserts contact by the top of inner sliding sleeve assembly 4 and controls The bottom of grip assembly 3, during inserting, it is inside that wedge 421 is controlled grip assembly 3 inwall hoop by contact Pressure, i.e. wedge 421 form fixing reducing ball seat under the common effect that guide cylinder 43 and contact control grip assembly 3；

(7) install lower contact 5, lower contact 5 upper end be connected control grip assembly 3 bottom be threaded, under connect 5 are sealed by sealing ring with being connected between control grip assembly 3.

The using method of the fracturing string of the present embodiment is as follows:

(1) according to the reservoir situation of Oil/gas Well, prepare the controllable confining of respective amount and sanding machine, by bottom valve A, K344 packer B, the described matching used controllable confining of respective amount and sanding machine, sand-proof hydraulic anchor G, hydraulic pressure Safety joint H assembles on oil pipe I so that it is form fracturing string；

(2) enter under the fracturing string that will assemble in the pit shaft of Oil/gas Well, make the sandblasting of the sanding machine of every one-level fracturing string Mouth is corresponding with the Reservoir Section position in Oil/gas Well；

(3) beating hydraulic pressure in oil pipe I, K344 packer B sets, each controlled packing on K344 packer B top Device does not sets, and by bottom valve, No. zero interval of the bottommost of reservoir can be carried out pressing crack construction, and No. zero interval pressing crack construction is tied Shu Hou, the liquid in oil pipe I suppresses state still in not termination of pumping so that this K344 packer B is still in setting state；

(4) in Oil/gas Well, put into first order low-density ball by the pitching plug valve of well head, fall in the controlled packing of the first order On the reducing ball seat 42 of device C, because in oil pipe, fluid pressure effect then builds the pressure and cuts off shear pin 46, described inner sliding sleeve assembly 4 The most described contact controls grip assembly 3 and glides, and the end cap 45 of sleeve 41 bottom runs to lower contact 5 recess to be stopped, In now reducing ball seat 42 comes downwards to the space 51 of lower contact, some wedges 421 411 are flared out by windowing, Reducing ball seat 42 internal diameter expands；Meanwhile, sleeve 41 is opened with contacting the inlet controlled between grip assembly 3, suppresses Liquid is entered in the feed pathway that contact controls grip assembly 3 by inlet, and eventually enters into packing element assembly 2 and central tube 6 Between liquid set in space, packing element assembly 3 expands then, it is achieved set；

After reducing ball seat 42 internal diameter expands, first order low-density ball continues traveling downwardly to matching used first order sanding machine D's On sliding sleeve tee, and building the pressure and cut off shear pin, first order low-density ball glides together with sliding sleeve tee, in sanding machine main body Sand jet outlet open, first order low-density ball slides in the K344 packer B of bottom under continuing together with sliding sleeve tee, And be seated at the lower contact of bottom K344 packer, thus block following passage, now bottom K344 packer B and First order controllable confining C is in setting state, and fracturing fluid enters an interval from sand jet outlet, carries out pressing crack construction, After a number interval pressing crack construction terminates, the liquid in oil pipe I suppresses state still in not termination of pumping so that K344 bottom this Packer B and first order controllable confining C is still in setting state；

(5) in Oil/gas Well, put into, by the pitching plug valve of well head, the second level low-density ball being relatively large in diameter, repeat step (4), low-density ball in the second level can in succession make second level controllable confining E set and and then open second level sanding machine F's Sand jet outlet, second level low-density ball slides in the first order controllable confining C of bottom under continuing together with sliding sleeve tee, and sits Fall at the end cap 45 at first order controllable confining C sleeve, thus block following passage, bottom K344 packer B Then unsealing, first order controllable confining C and second level controllable confining E is in setting state, and fracturing fluid is from sand jet outlet Entering No. two intervals, carry out pressing crack construction, after No. two interval pressing crack constructions terminate, the liquid in oil pipe I is still in not stopping Pump suppress state so that this first order packer C and second level controllable confining E is still in setting state；

(6) more intervals can be repeated step (5) and it is carried out pressing crack construction operation, thus complete fracturing string by While level pressing crack construction, it is achieved packer and the stepped setting of each controllable confining and gradually deblocking.

Embodiment 3

As shown in figs 1-9, a kind of HTHP stepped setting deblocking multistage fracturing tubing string of the present embodiment, described pressure break pipe Post comprises some to setting up and down and matching used controllable confining and sanding machine, and described fracturing string is the most sequentially Connect have bottom valve A, packer B, some to described matching used controllable confining and sanding machine, sand-proof hydraulic anchor G, Hydraulic safety connector H, is connected by oil pipe I between above-mentioned each instrument；

Described controllable confining include top connection 1, packing element assembly 2, contact control grip assembly 3, inner sliding sleeve assembly 4 and under Joint 5；

Wherein, described top connection 1 seals the upper end being fixedly arranged on central tube 6；

Further, described top connection 1 is additionally provided with regulation ring 11, described regulation ring 11 bottom and described packing element assembly 2 Upper end adjacent, described regulation ring 11 inwall and described top connection 1 are peripheral for threadeding.

Wherein, described packing element assembly 2 includes through upper glue tube base 21, packing element 22 and lower rubber cylinder seat that sulfuration connects as one 23。

Further, described packing element assembly 2 is additionally provided with the slip baffle ring 24 stoping described packing element assembly hoop to slide, Described slip baffle ring 24 is connected with described lower rubber cylinder seat 23 bottom inner thread, described slip baffle ring 24 be positioned at described under Glue tube base 23 contacts between control grip assembly 3 with described.

Wherein, described contact control grip assembly 3 includes crossover sub 31, lock ring 32, contact sleeve 33 and connecting cylinder 34；

Described crossover sub 31 upper end is connected with central tube 6 bottom outer periphery threads；

Described contact sleeve 33 is sheathed on the periphery of described inner sliding sleeve assembly 4 upper end, and described contact sleeve 33 periphery is provided with One ring recess 331, described crossover sub 31 inwall is provided with the second ring recess 311, and described lock ring 32 is positioned at described first ring recess 331 With in the lock space of described second ring recess 311 formation, described lock ring 32 surface is provided with elastic rubber layer, described contact sleeve Inside being provided with the first feed pathway, be provided with the second feed pathway in described crossover sub, described lock space is positioned at described first Between feed pathway and described second feed pathway, and it is connected with the two.

The upper end of described connecting cylinder 34 is adjacent with the bottom of described lower rubber cylinder seat 23, the upper end of described connecting cylinder 34 It is connected with the outer periphery threads of described crossover sub 31, the bottom of described connecting cylinder 34 and the upper end of described lower contact 5 Threaded.

Further, described contact sleeve 33 is slot tubular construction, and described slot is line cutting, if described first feed pathway is The liquid-retaining volume that dry described slot is formed.

Wherein, described inner sliding sleeve assembly 4 includes sleeve 41, reducing ball seat 42, guide cylinder 43, spring 44 and end cap 45；

Being connected by shear pin 46 is fixing between described sleeve 41 with described connecting cylinder 34, the upper end of described sleeve 41 is peripheral It is connected with crossover sub 31 inner wall sealing；In the middle part of described sleeve 41, hoop is provided with 6 and windows 411, described reducing ball seat 42 is 6 wedges 421, and described wedge 421 is by described 411 insertions of windowing, a part for described wedge 421 Windowing 411 described in being positioned at, another part is positioned at described sleeve 41, and the periphery of described wedge 421 is connected with described Cylinder 34 internal face contact, described wedge 421 is positioned at the section lower of described sleeve 41 and is provided with inclined-plane；

It is internal that described guide cylinder 43 is positioned at described sleeve 41, and fits with described sleeve 41 inwall, described guide cylinder 43 Inside being provided with spring 44, the upper surface of described guide cylinder 43 is abutted spacing by the inclined-plane of described wedge 421, described end cap 45 with described sleeve 41 bottom inwall for threadeding, the interior platform of the lower surface of described guide cylinder 43 and described end cap 45 Shoulder abuts, and the bottom of described sleeve 41 abuts with the outer shoulder of described end cap 45, and described spring 44 is by described end cap The compression of end face.

Wherein, the upper end of described lower contact 5 is connected with described connecting cylinder 34 lower periphery thread seal, described lower contact Space 51 it is provided with, when the most described contact of described inner sliding sleeve assembly 4 controls grip assembly 3 between 5 inwalls and described connecting cylinder 34 After downslide, described wedge 421 is positioned at described space 51.

Threaded connection place above-mentioned in the present embodiment is equipped with jackscrew and is fixed.

The assembling process of the controllable confining of the present embodiment is as follows:

(1) top connection 1 is fixed on bench vice；

(2) installing central tube 6, threaded with central tube 6 upper end in top connection 1 bottom, top connection 1 and center Sealed by sealing ring between pipe 6；

(3) regulation ring 11 is installed, regulates ring 11 with top connection 1 for threadeding, and fixed by jackscrew；

(4) installing packing element assembly 2, the packing element assembly 2 after sulfuration is sleeved on the periphery of central tube 6, upper glue tube base 21 And sealed by sealing ring between top connection 1；

(5) crossover sub 31 is installed, the bottom of the upper end of crossover sub 31 and central tube 6 for threadeding, turn All sealed by sealing ring between changing-over 31 and central tube 6 and lower rubber cylinder seat 23；

(6) slip baffle ring 24 is installed, for threadeding between slip baffle ring 24 with lower rubber cylinder seat 23 bottom, and by pushing up Silk is fixing；

(7) sleeve 41, contact sleeve 33, lock ring 32, shear pin 46 and the assembly of reducing ball seat 42 are assembled, will contact It is peripheral that set 33 is set in sleeve 41 upper end, is fixed on by lock ring 32 at first ring recess 331 on contact sleeve 33 top, 6 wedges 421 are inserted 6 of sleeve 41 correspondence and windows in 411；Shear pin 46 is fixed on the outer collarette of sleeve 41 In the some fixing holes arranged；

(8) assembly of installation steps (6), inserts the bottom of crossover sub 31 by sleeve 41 top of assembly, During inserting, lock ring 32 is extruded by crossover sub 31 inwall, when lock ring 32 is inserted into crossover sub 31 And during lock space between contact sleeve 33, the rubber layer on lock ring 32 surface is released, and makes crossover sub 31 and connect Touch and be relatively fixed between set 33；

(9) installing connecting cylinder 34, the upper end of connecting cylinder 34 is connected with crossover sub 31 outer periphery threads, and by jackscrew Fixing, in installation process, wedge 421 is by connecting cylinder 34 inwall hoop inward pressure；

(10) guide cylinder 43, spring 44 and end cap 45 are installed, are directed to cylinder 43 and insert sleeve 41, guide cylinder 43 Upper end abuts with the inclined-plane of wedge 421, is placed in guide cylinder 43 by spring 44, end cap 45 and sleeve 41 inwall Bottom is threaded, and is fixed by jackscrew, during end cap 45 screwed enters sleeve 41, and end cap 45 end face Compression spring 44, the elastic force of this spring 44 passes through guide cylinder 43 and then props up the inclined-plane of wedge 421；I.e. wedge 421 Fixing reducing ball seat is formed under the common effect of guide cylinder 43 and connecting cylinder 34；

(11) install lower contact 5, lower contact 5 upper end with crossover sub 31 bottom for threadeding, lower contact 5 And sealed by sealing ring between crossover sub 31.

The using method of the fracturing string of the present embodiment is as follows:

(1) according to the reservoir situation of Oil/gas Well, prepare the controllable confining of respective amount and sanding machine, by bottom valve A, K344 packer B, the described matching used controllable confining of respective amount and sanding machine, sand-proof hydraulic anchor G, hydraulic pressure Safety joint H assembles on oil pipe I so that it is form fracturing string；

(2) enter under the fracturing string that will assemble in the pit shaft of Oil/gas Well, make the sandblasting of the sanding machine of every one-level fracturing string Mouth is corresponding with the Reservoir Section position in Oil/gas Well；

(3) beating hydraulic pressure in oil pipe I, K344 packer B sets, each controlled packing on K344 packer B top Device does not sets, and by bottom valve, No. zero interval of the bottommost of reservoir can be carried out pressing crack construction, and No. zero interval pressing crack construction is tied Shu Hou, the liquid in oil pipe I suppresses state still in not termination of pumping so that this K344 packer B is still in setting state；

(4) in Oil/gas Well, put into first order low-density ball by the pitching plug valve of well head, fall in the controlled packing of the first order On the reducing ball seat 42 of device C, because in oil pipe, fluid pressure effect then builds the pressure and cuts off shear pin 46, described inner sliding sleeve assembly 4 The most described contact controls grip assembly 3 and glides, and the end cap 45 of sleeve 41 bottom runs to lower contact 5 recess to be stopped, In now reducing ball seat 42 comes downwards to the space between lower contact 5 and connecting cylinder 34, some wedges 421 are by windowing 411 are flared out, and reducing ball seat 42 internal diameter expands；Meanwhile, the inlet between sleeve 41 and contact sleeve 33 is opened, Suppress in the first feed pathway that liquid enters contact sleeve 33 by inlet, and enter crossover sub 31 via lock space The second feed pathway in, then eventually enter into the liquid between packing element 22 and central tube 6 and set in space, packing element 22 continues And expand, it is achieved set；

After reducing ball seat 42 internal diameter expands, first order low-density ball continues traveling downwardly to matching used first order sanding machine D's On sliding sleeve tee, and building the pressure and cut off shear pin, first order low-density ball glides together with sliding sleeve tee, in sanding machine main body Sand jet outlet open, first order low-density ball slides in the K344 packer B of bottom under continuing together with sliding sleeve tee, And be seated at the lower contact of bottom K344 packer B, thus block following passage, now bottom K344 packer B And first order controllable confining C is in setting state, fracturing fluid enters an interval from sand jet outlet, carries out pressing crack construction, After a number interval pressing crack construction terminates, the liquid in oil pipe I suppresses state still in not termination of pumping so that K344 bottom this Packer B and first order controllable confining C is still in setting state；

(5) in Oil/gas Well, put into, by the pitching plug valve of well head, the second level low-density ball being relatively large in diameter, repeat step (4), low-density ball in the second level can in succession make second level controllable confining E set and and then open second level sanding machine F's Sand jet outlet, second level low-density ball slides in the first order controllable confining C of bottom under continuing together with sliding sleeve tee, and sits Fall at the end cap 45 at first order controllable confining C sleeve, thus block following passage, bottom K344 packer B Then unsealing, first order controllable confining C and second level controllable confining E is in setting state, and fracturing fluid is from sand jet outlet Entering No. two intervals, carry out pressing crack construction, after No. two interval pressing crack constructions terminate, the liquid in oil pipe I is still in not stopping Pump suppress state so that this first order packer C and second level controllable confining E is still in setting state；

(6) more intervals can be repeated step (5) and it is carried out pressing crack construction operation, thus complete fracturing string by While level pressing crack construction, it is achieved packer and the stepped setting of each controllable confining and gradually deblocking.

It should be noted that the assembling process of controllable confining is only controlled for the present patent application in various embodiments above The some feasible assembling process of packer, not in order to limit invention, every assembling process corresponded to actual needs, with And in this assembling process, accessory therein is carried out any equal replacement, improvement etc., all in protection scope of the present invention Within.

In various embodiments above, the using method of fracturing string is only the some feasible of the fracturing string for the present patent application The description of pressing crack construction operation, not in order to limit invention, every pressing crack construction operation corresponded to actual needs, Yi Ji Any equal replacement that in this pressing crack construction process carries out accessory therein, improvement etc., all in protection scope of the present invention Within.

The foregoing is only presently preferred embodiments of the present invention, not in order to limit the present invention, all spirit in the present invention Within principle, any modification, equivalent substitution and improvement etc. made, should be included within the scope of the present invention.

Claims (10)

1. a HTHP stepped setting deblocking multistage fracturing tubing string, it is characterised in that: described fracturing string comprises some To setting up and down and matching used controllable confining and sanding machine, described fracturing string be sequentially connected with from the bottom to top bottom valve, Packer, some to described matching used controllable confining and sanding machine, sand-proof hydraulic anchor, hydraulic safety connector, on State and connected by oil pipe between each instrument；

Be provided with in described controllable confining can relatively controllable confining main body glide inner sliding sleeve assembly, described inner sliding sleeve assembly It is connected, between described inner sliding sleeve assembly and described controllable confining main body by shear pin is fixing with between described controllable confining main body Being provided with the inlet that can open, described inlet sets space with the liquid in described controllable confining main body and connects, described Being provided with reducing ball seat in inner sliding sleeve assembly, described reducing ball seat becomes big with the downslide internal diameter of described inner sliding sleeve assembly；

Be provided with in described sanding machine can sanding machine main body glides relatively sliding sleeve tee, described sliding sleeve tee and described sanding machine Connecting by shear pin is fixing between main body, described sanding machine main body is provided with the spray can glided and open by described sliding sleeve tee Sand mouth；

Reducing ball seat before described controllable confining reducing and the internal diameter phase of the sliding sleeve tee of the sanding machine of matched use With.

2. a kind of HTHP stepped setting deblocking multistage fracturing tubing string as claimed in claim 1, it is characterised in that: institute State inner sliding sleeve assembly and include sleeve, reducing ball seat, guide cylinder, spring and end cap；

It is connected by shear pin is fixing between described sleeve with described controllable confining main body；In the middle part of described sleeve, hoop is provided with some Windowing, described reducing ball seat is some wedges, described wedge by described insertion of windowing, the periphery of described wedge with Described controllable confining main body inner wall face contact, a part for described wedge be positioned at described in window, another part is positioned at In described sleeve, described wedge is positioned at the section lower of described sleeve and is provided with inclined-plane；

Described guide cylinder is positioned at described sleeve inner, and fits with described sleeve lining, is provided with spring in described guide cylinder, The upper surface of described guide cylinder is abutted spacing by the inclined-plane of described wedge, and described end cap with described sleeve bottom inwall is Threaded, the lower surface of described guide cylinder abuts with the interior shoulder of described end cap, the bottom of described sleeve and described end The outer shoulder of lid abuts, and described spring is compressed by described end cap end face.

3. a kind of HTHP stepped setting deblocking multistage fracturing tubing string as claimed in claim 1, it is characterised in that: institute State controllable confining main body and include that top connection, packing element assembly, contact control grip assembly and lower contact；

Described top connection seals the upper end being fixedly arranged on central tube；

The periphery of central tube is located at by described packing element assembly sealing shroud, forms liquid and sit between described packing element assembly and described central tube Envelope space；

Described contact controls grip assembly and is fixedly arranged on bottom, central tube periphery, and described contact controls to be provided with feed liquor inside grip assembly Passage；

Described inner sliding sleeve assembly is relatively fixedly arranged on contact by shear pin and controls on grip assembly, and described inner sliding sleeve assembly connects with described Being provided with the inlet that can open between touch-control grip assembly, described inlet sets space with described feed pathway and described liquid Connection；

Described lower contact seals the bottom being fixedly arranged on described contact control grip assembly.

4. a kind of HTHP stepped setting deblocking multistage fracturing tubing string as claimed in claim 3, it is characterised in that institute State packing element assembly to include through upper glue tube base, packing element and lower rubber cylinder seat that sulfuration connects as one.

5. a kind of HTHP stepped setting deblocking multistage fracturing tubing string as claimed in claim 3, it is characterised in that institute State contact control grip assembly and include crossover sub, lock ring, contact sleeve and connecting cylinder；

Described crossover sub upper end is connected with central tube bottom outer periphery threads；

Described contact sleeve is sheathed on the periphery of described inner sliding sleeve assembly upper end, and described contact sleeve periphery is provided with the first ring recess, Described crossover sub inwall is provided with the second ring recess, and described lock ring is positioned at the lock that described first ring recess is formed with described second ring recess Determine in space, in described contact sleeve, be provided with the first feed pathway, in described crossover sub, be provided with the second feed pathway, described Lock space is between described first feed pathway and described second feed pathway, and is connected with the two；

The upper end of described connecting cylinder is adjacent with the bottom of described packing element assembly, the upper end of described connecting cylinder and described turn The outer periphery threads of changing-over head connects, and threadeds with the upper end of described lower contact in the bottom of described connecting cylinder；

Described inner sliding sleeve assembly includes sleeve, reducing ball seat, guide cylinder, spring and end cap；

It is connected by shear pin is fixing between described sleeve with described connecting cylinder, in the periphery, upper end of described sleeve and crossover sub Wall is tightly connected；In the middle part of described sleeve, hoop is provided with some windowing, and described reducing ball seat is some wedges, described wedge shape Block by described insertion of windowing, a part for described wedge be positioned at described in window, another part is positioned at described sleeve, Peripheral and the described connecting cylinder internal face of described wedge contacts, and described wedge is positioned at the section lower of described sleeve and sets There is inclined-plane；

Described guide cylinder is positioned at described sleeve inner, and fits with described sleeve lining, is provided with spring in described guide cylinder, The upper surface of described guide cylinder is abutted spacing by the inclined-plane of described wedge, and described end cap with described sleeve bottom inwall is Threaded, the lower surface of described guide cylinder abuts with the interior shoulder of described end cap, the bottom of described sleeve and described end The outer shoulder of lid abuts, and described spring is compressed by described end cap end face；

Preferably, described lock ring surface is provided with elastic rubber layer.

6. a kind of HTHP stepped setting deblocking multistage fracturing tubing string as claimed in claim 5, it is characterised in that institute Stating contact sleeve is slot tubular construction, and described slot is line cutting, and described first feed pathway is that some described slots are formed Liquid-retaining volume.

7. a kind of HTHP stepped setting deblocking multistage fracturing tubing string as claimed in claim 5, it is characterised in that institute The upper end stating lower contact is connected with described connecting cylinder lower periphery thread seal, described lower contact inwall and described connecting cylinder Between be provided with space, when the most described contact of described inner sliding sleeve assembly controls after grip assembly glides, and described wedge is positioned at described In space.

8. a kind of HTHP stepped setting deblocking multistage fracturing tubing string as claimed in claim 5, it is characterised in that institute Stating the slip baffle ring being additionally provided with to stop described packing element assembly hoop to slide on packing element assembly, described slip baffle ring is with described Lower rubber cylinder seat bottom inner thread connects, and described slip baffle ring is positioned between described lower rubber cylinder seat and described crossover sub.

9. a kind of HTHP stepped setting deblocking multistage fracturing tubing string as claimed in claim 3, it is characterised in that institute Stating and be additionally provided with regulation ring in top connection, described regulation ring bottom is adjacent with the upper end of described packing element assembly, described regulation Ring inwall with described top connection periphery for threadeding.

10. a kind of HTHP stepped setting deblocking multistage fracturing tubing string as described in as arbitrary in claim 5,6,7,9 Using method, including following order step:

(1) according to the reservoir situation of Oil/gas Well, controllable confining and the sanding machine of respective amount is prepared, by bottom valve, packing Device, the described matching used controllable confining of respective amount and sanding machine, sand-proof hydraulic anchor, hydraulic safety connector are at oil Assemble on pipe so that it is form fracturing string；

(2) enter under the fracturing string that will assemble in the pit shaft of Oil/gas Well, make the sandblasting of the sanding machine of every one-level fracturing string Mouth is corresponding with the Reservoir Section position in Oil/gas Well；

(3) beating hydraulic pressure in oil pipe, packer setting, each controllable confining on packer top does not sets, and can pass through at the end Valve carries out pressing crack construction to No. zero interval of the bottommost of reservoir, after No. zero interval pressing crack construction terminates, and the liquid in oil pipe State is suppressed so that this packer is still in setting state still in not termination of pumping；

(4) in Oil/gas Well, put into first order low-density ball by the pitching plug valve of well head, fall in the controlled packing of the first order On the reducing ball seat of device, because in oil pipe, fluid pressure effect then builds the pressure and cuts off shear pin, described inner sliding sleeve assembly is relatively described Contact controls grip assembly and glides, and the end cap of lower cartridge runs and stops to recess in lower contact, and now reducing ball seat comes downwards to In space between lower contact and connecting cylinder, some wedges are flared out by windowing, and reducing ball seat internal diameter expands, with This simultaneously, sleeve is opened with inlet contact inner room, suppresses liquid logical by the first feed liquor of inlet entrance contact sleeve In road, and enter via lock space in the second feed pathway of crossover sub, then eventually enter between packing element and central tube Liquid set in space, packing element expand, it is achieved set；

After reducing ball seat internal diameter expands, first order low-density ball continues traveling downwardly to the sliding sleeve tee of matching used sanding machine, And build the pressure and cut off shear pin, first order low-density ball glides together with sliding sleeve tee, and the sand jet outlet in sanding machine main body is opened, First order low-density ball continues to be snapped down in lower packer together with sliding sleeve tee, and is seated under lower packer and connects At Tou, thus blocking following passage, now bottom packer and first order controllable confining are in setting state, pressure break Liquid enters an interval from sand jet outlet, carries out pressing crack construction, and after an interval pressing crack construction terminates, the liquid in oil pipe is still Be in not termination of pumping suppresses state so that bottom this, packer and first order controllable confining are still in setting state；

(5) in Oil/gas Well, put into, by the pitching plug valve of well head, the second level low-density ball being relatively large in diameter, repeat step (4), low-density ball in the second level can in succession make second level controllable confining set and and then open the sandblasting of second level sanding machine Mouthful, second level low-density ball continues to be snapped down in the first order controllable confining of bottom together with sliding sleeve tee, and is located At the end cap of first order controllable confining sleeve, thus blocking following passage, bottom packer unseals then, the first order Controllable confining and second level controllable confining are in setting state, and fracturing fluid enters No. two intervals from sand jet outlet, presses Splitting construction, after No. two interval pressing crack constructions terminate, the liquid in oil pipe suppresses state still in not termination of pumping so that this is years old One-level packer and second level controllable confining are still in setting state；

(6) more intervals can be repeated step (5) and it is carried out pressing crack construction operation, thus complete fracturing string by While level pressing crack construction, it is achieved packer and the stepped setting of each controllable confining and gradually deblocking；

Preferably, described packer is K344 packer.