CN207131369U - A kind of anti-channeling layer cementing unit - Google Patents

Abstract

It the utility model is related to a kind of anti-channeling layer cementing unit, including the bunch tube in well, the bottom of bunch tube is provided with packer, packer is corresponding with the position of the thin interlayer of well, there is annular pressure compensator the lower end of packer by sleeve pipe connection, and there is float collar the lower end of annular pressure compensator by sleeve pipe connection.Packer includes top connection and central tube, and the upper end of top connection mutually spins with upper square casing, and the upper end of central tube is screwed in top connection lower end；Packing element is set with the middle part of central tube, packing element upper end is embedded in packing element bearing, packing element bearing is sleeved on central tube, elastic supporting mechanism is provided between the top of packing element bearing and top connection, periphery in the middle part of packing element is provided with twice packing element neck respectively embedded with setting hoop, and the lower surface of packing element is provided with hydraulic compression mechanism.The device can reliable sealed thin interlayer, prevent oil gas water breakthrough.

Description

A kind of anti-channeling layer cementing unit

Technical field

A kind of cementing unit of oil drilling is the utility model is related to, more particularly to a kind of anti-channeling layer cementing unit, is belonged to Petroleum drilling technology field.

Background technology

With deepening continuously for In Oil Field Exploration And Development, the oil sheet old area adjustment well that oil gas is active, strata pressure is complicated is got over Come it is more, to the performance requirement of oil field drilling completion downhole tool also more and more higher.Especially into high water cut viscous heavy crude oil, due to Note adopts unbalanced influence, the multi pressure series of strata on longitudinal direction and deposit, the increase of seepage flow flow, interlayer contradiction protrude, oil reservoir is more and thin, Sealing segment length, cement mortar are difficult to meet each stressor layer demand, and oil gas water breakthrough easily occurs.In terms of cementing quality requirement, to prevent Alter mutually logical between the oil sheet being only adjusted, sealing quality requirement is very high.The cementing quality of oil sheet is difficult in actual job Ensure, seriously constrain effective implementation of development plan, how to resolve oil sheet adjustment well water breakthrough problem turn into work as Before the technical barrier that must pull against.

One of main downhole tool as petroleum exploration and development, packer be widely used in completion well cementing operation and In all kinds of packing bridge blinding operations, the packer used in the market is mainly external casing packer, and external casing packer is one Kind permanent type external packer of pipe, expansion packing element is used the downhole packing and bridge blinding of various purposes to be realized, to improving for potted component There is remarkable effect with oily, gas and water well well cementation total completion time is improved.Packer is broadly divided into mechanical setting, setting two class of fluid power.

The quality of packer sealing quality is critically depend on the size of contact stress between the borehole wall and rubber tube, conventional packing Stereotyped structure without packing element dilatancy in the structure of device, also no supporting mechanism supports after packing element expansion.Entering During row packing, the deformation after being expanded due to packing element is irregular, has spikes/low- points on same cross section, dilation occurs Distortion is overlapping, causes seal line to be moved about, it is impossible to realizes the sealing effectiveness similar to abacus pearl.In order to realize effective packing, Generally require to make up by lengthening the length of packing element, make to form larger contact area between packing element and the borehole wall, to realize Face contact sealing, this kind of seal form need enough packing element length to ensure sealing effectiveness.Therefore the packing element of conventional packer Length reaches 1.2~1.5m, causes the length of whole packer to be generally more than 3m.

Oil gas well capacity depends primarily on Inter-zonal packing degree, and Inter-zonal packing degree is decided by the close of interface of cementing the well Envelope degree.Sealing layer is generally referred to as thin interlayer in 3m, and for the exceptional well of thin interlayer, conventional packer can not use, nothing Method realizes the packing requirement that oil mining proposes, longer conventional packer can not be placed in thin interlayer；Can if placing by force Oil-gas Layer is insulated, influences the production such as later stage perforation, oil recovery；Or cause to alter groove rate very high.In addition, packer length is long, fortune Defeated inconvenience, and in the big angle buildup interval of dog-leg, be not easy tripping in, limit use to a certain extent.

Utility model content

The purpose of this utility model is, overcomes problems of the prior art, there is provided a kind of anti-channeling layer cementing unit, Below 3m thin interlayer can be reliably sealed, prevents oil gas water breakthrough completely.

To solve above technical problem, a kind of anti-channeling layer cementing unit of the present utility model, including the set in well Pipe string, the inner chamber of described sleeve pipe string are provided with the plug that can unidirectionally move downward, and the circumference of the plug is provided with multiple tracks shirt rim, institute State shirt rim and the inwall of described sleeve pipe string realizes sealing, the bottom of described sleeve pipe string is provided with packer, the packer and well The position of thin interlayer is corresponding, and there are annular pressure compensator, the annular pressure in the lower end of the packer by sleeve pipe connection There is float collar the lower end of compensator by sleeve pipe connection.

Relative to prior art, the utility model achieves following beneficial effect：1. cementing truck is first used to bunch tube inner chamber Flushing spacer fluid is injected, rinses out the mud of the borehole wall and casing wall and loose mud cake；Injected again with cementing truck to bunch tube inner chamber Cement mortar；Then plug is put into bunch tube inner chamber, then promotes plug descending with drilling fluid pump injection drilling fluid, plug will cover Cement mortar in pipe string presses down and the annular region outside sleeve pipe；When plug reaches packer, the cement mortar in annular space Reach the top of sealing layer；Drilling fluid pump is pressurized to packer working pressure, and plug opens packer, and then plug continues When coming downwards to close to annular pressure compensator, use cementing truck to continue to be pressurized to packer set pressure value with small displacement, make envelope Setting, and voltage stabilizing 3~5 minutes is realized in the borehole wall at sealing layer every device；Cementing truck continues to be pressurized to annular space pressure with small displacement The opening pressure value of force compensating device, makes plug open annular pressure compensator；Cementing truck continues to promote under plug with small displacement OK, stop when plug comes downwards to float collar upper surface, build the pressure again to bruising pressure value, and voltage stabilizing 5~7 minutes；Then cement Car release, after confirming that the inner chamber of bunch tube is not returned, it is solidifying to continue spacious pressure time.2. traditional face sealing is changed to by line using packer Sealing, substantially reduces the total length of packer, below 3m thin interlayer can reliably be sealed, prevent fluid from mutually altering, Ensure the cementing quality of thin interlayer well, improve oil well life-span and yield；It is readily transported using packer and in the big well section of dog-leg It is easy to tripping in, reduces requirement of the packer to dog-leg severity, widen use range；After 3. plug opens packer, packer Packing element starts outwards to expand, and plug is pushed at annular pressure compensator and built the pressure to packer set pressure value, and the pressure is not Be enough to open annular pressure compensator, with ensure the packing element of packer continue expansion realize on the borehole wall it is setting；4. cement mortar During aquation gelling, three dimensions net is internally formed in slurry, between cement granules and they are between the borehole wall and sleeve pipe, Mutually overlap joint gets up to form a kind of space grid structure, a part of weight of cement mortar post is suspended on the borehole wall and sleeve pipe, Produce weightlessness effect；When slurry post effective pressure is less than strata pressure, the oil, gas and water in stratum will be invaded in pit shaft.This practicality When new middle plug is come downwards to close to annular pressure compensator, using cementing truck to continue supercharging with 200L/min small displacement makes envelope It is setting every device, then or with same low discharge promote plug to open annular pressure compensator, annular pressure can be reduced Pressure excitement when compensator is opened, pressure leakage stratum is prevented, then promotes plug to continue traveling downwardly using small displacement, to production string Annular space bottom is applied with additonal pressure, and annular space head of liquid declines caused by cement slurry weight loss etc. between compensation and increase waiting-on-cement, Limitation formation fluid enters annular space, so as to reach the purpose for improving cementing quality.5. cementing truck release, confirm the inner chamber of bunch tube After not returning, illustrate the non-return dependable performance of float collar, it is solidifying to then proceed to spacious pressure time, it is ensured that this well cementing process is safe and reliable.⑥ The opening pressure value of annular pressure compensator is more than setting more than the pressure value 5MPa of packer, it can be ensured that packer has been realized It is complete it is setting after, just open annular pressure compensator progress pressure compensation；7. the utility model is mended by packer and annular pressure Repay device collaboration to use, can reliably solve the problems, such as the anti-channeling of oil sheet adjustment well.

As improvement of the present utility model, the packer includes top connection and central tube, and the upper end of the top connection is set There is the box thread mutually to be spun with upper square casing, the upper end of the central tube is screwed in the box thread of top connection lower end；In described Be set with packing element in the middle part of heart pipe, the upper end of the packing element is embedded in packing element bearing, the packing element bearing be sleeved on it is described in On heart pipe, elastic supporting mechanism, the packing element axle are provided between the top of the packing element bearing and the lower surface of the top connection Be provided with twice packing element neck to the periphery at middle part, in the packing element neck respectively between setting hoop, twice setting hoop between At a certain distance, the lower surface of the packing element is provided with hydraulic compression mechanism.Packing element is whole by the upward extruding of hydraulic compression mechanism Body is moved up and outwards expanded, and the upper end of packing element is stuck in promotion packing element bearing upward sliding, packing element bearing in packing element bearing The reaction force of elastically supported mechanism so that packing element both ends are by stable extruding force；Due to being provided with twice in the middle part of packing element Setting hoop, is allowed to outwards to expand by blocking in the middle part of packing element, then each above and below twice setting hoop to be formed together Similar to the expansion loop of abacus pearl；Twice expansion loop forms the low regular shape in middle high both sides respectively, due to each expansion The both sides up and down of circle are reliably limited and supported, therefore twice expansion loop is not in distortion, and seal line will not move about, Ke Yiqi To the effect of twice " O " type sealing ring, dual-seal is formed, effectively increases the sealing effectiveness of packer；Make packer need not Declined by lengthening packing element length to make up sealing effectiveness caused by seal line is moved about.The utility model sets fixed in the middle part of packing element Shape hoop and after elastic supporting mechanism is set above the packing element bearing so that packing element length of the present utility model only for it is conventional every 1/3~1/5 or so of device packing element length, and then packer entire length can be made to shorten to below 1.2m, it can be competent at completely Thickness is setting for the thin interlayers of below 3m.

As further improvement of the utility model, the elastic supporting mechanism includes being sleeved on the central tube periphery Retainer ring and spring steel support ring, the upper end of the retainer ring are resisted against the lower end of the top connection, the lower end of the retainer ring Provided with retainer ring horn mouth, the bell-mouthed root of retainer ring communicates with the retainer ring annular recess being recessed upwards, the bullet The upper end of spring bracing members ring is inlaid in the retainer ring annular recess, and the bottom of the spring steel support ring is evenly distributed with more The groove of road lower ending opening makes the bottom of spring steel support ring form multiple flexible flaps, the lower end difference of each flexible flaps It is flared out.The lower end that retainer ring is resisted against top connection provides support for spring steel support ring, and packing element is withstood when packing element is squeezed When bearing moves up, each flexible flaps are further opened in umbrella, and retainer ring annular recess securely fixes spring steel support The full circle circumferential portion of ring, retainer ring horn mouth provide space and limit for the opening of each flexible flaps in spring steel support ring lower end Position, when being fitted on the outside of each flexible flaps on retainer ring horn mouth, opening maximum is reached, has been carried to packing element bearing and packing element For uniform reaction force；Simultaneously when packing element is expanded into abacus pearl, each flexible flaps uniformly opened play supporting bracket Effect, support and support are formed to the expansion loop of packing element, expansion loop is kept the abacus pearl of rule, realizes on same section Linear sealing is realized, and ensures that sealing effectiveness is reliable.

As further improvement of the utility model, the upper end of the packing element bearing is provided with up-small and down-big packing element bearing and bored Shape inclined-plane, the lower end of each flexible flaps are born against on the circumference of the packing element bearing tapered slope, each packing element bearing The inclination angle of tapered slope and the bell-mouthed inclination angle of the retainer ring are equal；The root periphery of each flexible flaps is respectively equipped with bullet Property limb arc groove, each flexible flaps arc groove be located on same circumference and positioned at the retainer ring it is bell-mouthed Root.The lower end of flexible flaps is born against on the circumference of packing element bearing tapered slope so that packing element, which is squeezed, withstands packing element When bearing moves up, each flexible flaps are further opened along packing element bearing tapered slope in umbrella, and flexible flaps are to packing element Bearing tapered slope applies reaction force, when flexible flaps, which are flared to inner side, to be bonded completely with packing element bearing tapered slope, respectively The outside of flexible flaps is just fitted on retainer ring horn mouth, i.e., each flexible flaps have been flared to maximum, the expansion to packing element Circle forms support and support；Flexible flaps arc groove causes the crooked position of each flexible flaps to be consistent, and makes each elastic valve The supporting bracket circularity that piece is formed after opening is very high, and increase can ensure that the regular shape of packing element expansion loop is stable.

As further improvement of the utility model, the bottom of the spring steel support ring is provided with rubber protecting jacket, described Rubber protecting jacket is covered in the periphery of each flexible flaps, and the periphery of the rubber protecting jacket and the periphery of the retainer ring are put down Together, the upper end of the rubber protecting jacket is embedded in the retainer ring horn mouth and the flexible flaps arc groove；The rubber The position that protective case contacts with the retainer ring lower edge is provided with rubber protecting jacket annular recess.The periphery of rubber protecting jacket and fixation The periphery of ring is concordantly advantageous to whole packer and smoothly glided with sleeve pipe；Rubber protecting jacket by each flexible flaps be covered in can be with Play a protective role, prevent during going into the well, the foreign matter that the lower end of flexible flaps is touched on the borehole wall causes tilting impaired；Rubber In the upper end insertion flexible flaps arc groove of glue protective case, some reinforcement are carried out to the most weak position of flexible flaps, and not Influence the opening of flexible flaps；Rubber protecting jacket annular recess is easy to rubber protecting jacket to bend deformation here, prevents rubber from protecting Sheath forms larger obstruction power after being extruded.

As further improvement of the utility model, the hydraulic compression mechanism includes embracing the cunning in the central tube periphery Set, the top braces of the sliding sleeve internal perisporium of step in the lower section of the packing element lower surface, the sliding sleeve upper end pass through O-shaped Circle realizes and sealed that the upper end of the sliding sleeve is provided with sliding sleeve outer step, glue is connected with the sliding sleeve outer step with the central tube Cylinder pressure cap, the lower end periphery of the packing element are plugged in the rubber cylinder pressing cap；The inner chamber of the sliding sleeve is provided with center spud, described The periphery wall that the upper end of center spud is screwed on the male thread of central tube lower end and center spud upper end outer step passes through O-ring Realize and seal with the inwall of the sliding sleeve, the lower end of the center spud is stretched out from the lower end of the sliding sleeve；The sliding sleeve upper end Space between the lower section of interior step and the top of center spud upper end outer step forms the hydraulic cavities of the sliding sleeve；It is described The lower port inner chamber of sliding sleeve is provided with ring cavity, and elastic lock sleeve is provided with the ring cavity, and the elastic lock sleeve is embraced in institute The periphery of center spud is stated, and the inwall of the elastic lock sleeve is provided with box thread, the lower end periphery of the sliding sleeve is connected with lock tube Nut, the interior step of the lock tube nut are resisted against the lower section of the elastic lock sleeve；The stage casing of the center spud short transverse Periphery is provided with the stopping lock tooth that can be engaged with the box thread of elastic lock sleeve.Rubber cylinder pressing cap limits the lower end of packing element, prevents The lower end of its packing element outwards expands protrusion；When slide over hydraulic cavities fluid power act under head on packing element it is up when, lock tube nut It is up with sliding sleeve, outer wall upward sliding of the elastic lock sleeve along center spud is push, elastic lock sleeve, which is provided with axial groove, makes elasticity Lock tube has certain deformability, will can only by monodirectional locking, sliding sleeve when elastic lock sleeve, which is gone upward to, to be engaged with stopping lock tooth Upward packing element, even if fluid power disappears, sliding sleeve will not also glide release.

As further improvement of the utility model, the bottom of central tube position corresponding with the hydraulic cavities is along footpath At least two blind pluggings are plugged with to symmetrical, the circumference of the blind plugging, which is provided with, is easy to the blind plugging V-shaped groove that blind plugging neatly fractures, described The bottom land of blind plugging V-shaped groove is concordant with the inwall of the central tube, and the blind plugging is provided with what ecto-entad extended along blind plugging center line Half deep hole, the axis of the cecum of half deep hole than the blind plugging V-shaped groove closer to the central tube；The external end head of the blind plugging Pushed down respectively by blind plugging gland, the blind plugging gland is screwed in the blind plugging gland screwed hole of the center spud respectively, described Blind plugging gland, which is distributed with, multiple to be communicated with half deep hole of the blind plugging.After blind plugging is inserted into the tube wall of central tube, screw on blind Stifled gland compresses blind plugging, and before blind plugging is broken off, hydraulic cavities and center tube cavity are obstructed, and now packer is in the lock state, Preventing from surprisingly working during going into the well causes mistake to expand.After plug is dropped down onto in blind plugging, drilling fluid pump is pressurized to packer Working pressure, plug fracture blind plugging at the bottom land of blind plugging V-shaped groove, and the drilling fluid of center tube cavity is through blind plugging center Half deep hole and gland through hole enter the hydraulic cavities of sliding sleeve, and the fluid power promotion sliding sleeve of hydraulic cavities is up, and packing element starts to expand.Plug after Continuous come downwards to stops at annular pressure compensator and is pressurized to packer set pressure value, and packing element is expanded to maximum, in sealing layer Realize setting in place.

As further improvement of the utility model, holding screw is connected with the lower circumferential of the lock tube nut, institute The inner termination of holding screw is stated in the counterbore of the center spud periphery, the lower surface supported underneath of the lock tube nut has Locking nut, the locking nut are screwed on the center spud.Screwing in holding screw can be by lock tube nut locking in In heart adapter, prevent lock tube from being malfunctioned in transportation；Locking nut determines the bottom dead centre of sliding sleeve, and anti-anti-skid sheath slips.

As further improvement of the utility model, the packing element total length is 300 ~ 350mm, the width of the setting hoop For the 1/32 ~ 1/30 of the packing element total length, the spacing between twice setting hoop is the 1/16 ~ 1/15 of the packing element total length. As a result of reliable twice linear sealing, packing element length of the present utility model is only to be conventional every the 1/3~1/5 of device packing element length Left and right, and then packer entire length can be made to shorten to below 1.2m, thickness can be competent at completely for the thin interlayers of below 3m It is setting.

As further improvement of the utility model, connect on the compensator that the annular pressure compensator includes mutually spinning Pipe and compensator lower linking tube, the inner chamber of the compensator lower linking tube are provided with level pressure set, the outer wall of the level pressure set and the compensation The inwall gap of device lower linking tube coordinates, and the outer wall of level pressure set is symmetrically plugged with two level pressure pins, the level pressure pin External end head be plugged on respectively in bushing, the lower surface of the bushing is respectively supported at the interior step of the compensator lower linking tube On, the internal diameter of the bushing, compensator upper connecting tube and compensator lower linking tube is equal；The circumference of the level pressure pin, which is provided with, to be easy to The level pressure pin V-shaped groove that pin neatly fractures, the bottom land of the level pressure pin V-shaped groove are concordant with the inwall of the bushing；It is described The upper end of bushing is provided with up big and down small bushing horn mouth, the upper end of the level pressure set protrude from the bushing it is bell-mouthed on Edge, the rim of a bowl to lower recess that the upper port that the level pressure covers is provided with.In setting procedure at sealing layer, plug falls packer Level pressure is put, and continues to be pressurized to the opening pressure value of annular pressure compensator using small displacement, and the pressure of plug is by level pressure pin Cut off at the bottom land of level pressure pin V-shaped groove, because the bottom land of level pressure pin V-shaped groove is concordant with the inwall of bushing, level pressure pin After being cut off, level pressure set can smoothly glide；Annular space below sealing layer applies additonal pressure, between compensation and increase waiting-on-cement Annular space head of liquid caused by cement slurry weight loss etc. declines.After plug presses several times, easily there is overlap, level pressure set in its lower surface Upper end protrude from the bell-mouthed upper limb of bushing, prevent plug lower end overlap scratch arrive bushing, the bushing loudspeaker of bushing upper end Mouth more avoids the scratch of plug, and the rim of a bowl that level pressure puts port just accepts the lower end of plug, is covered altogether beneficial to plug and level pressure Axis combines.

Brief description of the drawings

The utility model is described in further detail with reference to the accompanying drawings and detailed description, accompanying drawing only provides ginseng Examine and used with explanation, be not used to limit the utility model.

Fig. 1 is the working condition one of the utility model anti-channeling layer cementing unit.

Fig. 2 is the working condition two of the utility model anti-channeling layer cementing unit.

Fig. 3 is the utility model anti-channeling layer cementing unit working condition three.

Fig. 4 is the structural representation of packer in Fig. 1.

Fig. 5 is the enlarged drawing at I position in Fig. 4.

Fig. 6 is the enlarged drawing at II position in Fig. 4.

Fig. 7 is the enlarged drawing at III position in Fig. 4.

Fig. 8 is the structural representation of Fig. 1 middle ring sky pressure compensators.

Fig. 9 is the enlarged drawing at IV position in Fig. 8.

In figure：A. packer；B. plug；C. annular pressure compensator；D. float collar；E. float shoe；1. top connection；2. center Pipe；3. elastic supporting mechanism；3a. retainer rings；3b. spring steel support rings；3b1. flexible flaps；3b2. flexible flaps arcs are recessed Groove；3c. rubber protecting jackets；3c1. rubber protecting jacket annular recess；4. packing element bearing；4a. packing element bearing tapered slopes；5. glue Cylinder；6. setting hoop；7. rubber cylinder pressing cap；8. sliding sleeve；9. center spud；9a. stopping lock teeth；10. hydraulic cavities；11. blind plugging；11a. Half deep hole；11b. blind plugging V-shaped grooves；12. blind plugging gland；12a. gland through holes；13. elastic lock sleeve；14. lock tube nut；15. tightening Screw；16. locking nut；17. compensator upper connecting tube；18. compensator lower linking tube；19. level pressure set；19a. the rims of a bowl；20. level pressure pin Nail；21. bushing；21a. bushing horn mouths.

Embodiment

As shown in Figures 1 to 9, anti-channeling layer cementing unit of the present utility model includes the bunch tube being located in well, sleeve pipe The inner chamber of string is provided with the plug B that can unidirectionally move downward, and plug B circumference is provided with multiple tracks shirt rim, shirt rim and bunch tube it is interior Wall realizes sealing, and the bottom of bunch tube is provided with packer A, and packer A is corresponding with the position of the thin interlayer of well, packer A's There is annular pressure compensator C lower end by sleeve pipe connection, and there is float collar D annular pressure compensator C lower end by sleeve pipe connection, floats There is float shoe E hoop D lower end by sleeve pipe connection.

Packer A includes top connection 1 and central tube 2, and the upper end of top connection 1 is provided with the female spiral shell mutually to be spun with upper square casing Line, the upper end of central tube 2 are screwed in the box thread of the lower end of top connection 1；The middle part of central tube 2 is set with packing element 5, packing element 5 Upper end is embedded in packing element bearing 4, and packing element bearing 4 is sleeved on central tube 2, the top of packing element bearing 4 and the lower end of top connection 1 It is provided with elastic supporting mechanism 3 between face, the periphery at the axial middle part of packing element 5 is provided with twice packing element neck, embedding respectively in packing element neck Equipped with setting hoop 6, spaced apart between twice setting hoop 6, the lower surface of packing element 5 is provided with hydraulic compression mechanism.

Packing element 5 is integrally moved up and outwards expanded by the upward extruding of hydraulic compression mechanism, the upper end quilt of packing element 5 It is stuck in packing element bearing 4 and promotes the upward sliding of packing element bearing 4, the reaction force of the elastically supported mechanism 3 of packing element bearing 4, makes The both ends of packing element 5 are obtained by stable extruding force；Because the middle part of packing element 5 is provided with twice setting hoop 6, the middle part of packing element 5 is blocked and is allowed to Can not outwards it expand, it is then each above and below twice setting hoop 6 to form the expansion loop for being similar to abacus pearl together；Two Road expansion loop forms the low regular shape in middle high both sides respectively, because the both sides up and down of each expansion loop are reliably limited and propped up Support, therefore twice expansion loop is not in distortion, seal line will not move about, and can play a part of twice " O " type sealing ring, shape Into dual-seal, the sealing effectiveness of packer is effectively increased；Make packer without making up sealing by lengthening packing element length Sealing effectiveness declines caused by line is travelling.The utility model sets setting hoop 6 at the middle part of packing element 5 and above packing element bearing 4 After elastic supporting mechanism 3 is set so that packing element length of the present utility model is only to be conventional every 1/3~1/5 left side of device packing element length The right side, and then packer entire length can be made to shorten to below 1.2m, the seat that thickness is the thin interlayers of below 3m can be competent at completely Envelope.

Elastic supporting mechanism 3 includes the retainer ring 3a and spring steel support ring 3b, retainer ring 3a for being sleeved on the periphery of central tube 2 Upper end be resisted against the lower end of top connection 1, retainer ring 3a lower end is provided with retainer ring horn mouth, the bell-mouthed root of retainer ring with The retainer ring annular recess being recessed upwards is communicated, and spring steel support ring 3b upper end is inlaid in retainer ring annular recess, spring The groove that bracing members ring 3b bottom is evenly distributed with multiple tracks lower ending opening makes spring steel support ring 3b bottom form multiple bullets Property limb 3b1, each flexible flaps 3b1 lower end is flared out respectively.

The lower end that retainer ring 3a is resisted against top connection 1 provides support for spring steel support ring 3b, is withstood when packing element 5 is squeezed When packing element bearing 4 moves up, each flexible flaps 3b1 further opens in umbrella, and retainer ring annular recess securely fixes bullet Spring bracing members ring 3b full circle circumferential portion, retainer ring horn mouth are each flexible flaps 3b1 in spring steel support ring 3b lower ends opening Space and spacing is provided, when being fitted on the outside of each flexible flaps 3b1 on retainer ring horn mouth, it is maximum to have reached opening, Uniform reaction force is provided to packing element bearing 4 and packing element 5；Simultaneously when packing element 5 is expanded into abacus pearl, that uniformly opens is each Flexible flaps 3b1 plays a part of supporting bracket, forms support and support to the expansion loop of packing element 5, expansion loop is kept rule Abacus pearl, realize and linear sealing is realized on same section, and ensure that sealing effectiveness is reliable.

The upper end of packing element bearing 4 lower end provided with up-small and down-big packing element bearing tapered slope 4a, each flexible flaps 3b1 point It is not resisted against on packing element bearing tapered slope 4a circumference, each packing element bearing tapered slope 4a inclination angle and retainer ring are bell-mouthed Inclination angle is equal；Each flexible flaps 3b1 root periphery is respectively equipped with flexible flaps arc groove 3b2, and each flexible flaps arc is recessed Groove 3b2 is located on same circumference and is located at the bell-mouthed root of retainer ring.

Flexible flaps 3b1 lower end is born against on packing element bearing tapered slope 4a circumference so that packing element 5 is squeezed When withstanding packing element bearing 4 and moving up, each flexible flaps 3b1 further opens along packing element bearing tapered slope 4a in umbrella, Flexible flaps 3b1 applies reaction force to packing element bearing tapered slope 4a, when flexible flaps 3b1 is flared to inner side and packing element bearing When tapered slope 4a is bonded completely, each flexible flaps 3b1 outside is just fitted on retainer ring horn mouth, i.e., each flexible flaps 3b1 has been flared to maximum, and support and support are formed to the expansion loop of packing element 5；Flexible flaps arc groove 3b2 causes each elastic valve Piece 3b1 crooked position is consistent, and the supporting bracket circularity for making each flexible flaps 3b1 be formed after opening is very high, and increase can Ensure that the regular shape of packing element expansion loop is stable.

Spring steel support ring 3b bottom is provided with rubber protecting jacket 3c, and rubber protecting jacket 3c is covered in each flexible flaps 3b1 Periphery, rubber protecting jacket 3c periphery is concordant with retainer ring 3a periphery, rubber protecting jacket 3c upper end insertion retainer ring loudspeaker In mouth and flexible flaps arc groove 3b2；Rubber protecting jacket 3c protects with the position that retainer ring 3a lower edges contact provided with rubber Collar shape groove 3c1.

Rubber protecting jacket 3c periphery is concordant with retainer ring 3a periphery be advantageous to whole packer A with sleeve pipe it is smooth under It is sliding；Rubber protecting jacket 3c by each flexible flaps 3b1 be covered in it is interior can play a protective role, prevent during going into the well, elasticity The foreign matter that limb 3b1 lower end is touched on the borehole wall, which causes to tilt, to be damaged；Rubber protecting jacket 3c upper end insertion flexible flaps arc In connected in star 3b2, some reinforcement are carried out to position most weak flexible flaps 3b1, and do not influence flexible flaps 3b1 opening； Rubber protecting jacket annular recess 3c1 is easy to rubber protecting jacket 3c to bend deformation here, after preventing rubber protecting jacket 3c to be extruded Form larger obstruction power.

Hydraulic compression mechanism includes embracing the sliding sleeve 8 in the periphery of central tube 2, and the top braces of sliding sleeve 8 are in the lower surface of packing element 5 Lower section, the internal perisporium of step realizes and sealed that the upper end of sliding sleeve 8 is provided with sliding sleeve between outer land by O-ring and central tube 2 in sliding sleeve upper end Rank, rubber cylinder pressing cap 7 is connected with sliding sleeve outer step, the lower end periphery of packing element 5 is plugged in rubber cylinder pressing cap 7；The inner chamber of sliding sleeve 8 is set There is a center spud 9, the upper end of center spud 9 is screwed on the male thread of the lower end of central tube 2 and the upper end outer step of center spud 9 Periphery wall realizes and sealed that the lower end of center spud 9 is stretched out from the lower end of sliding sleeve 8 by the inwall of O-ring and sliding sleeve 8；On sliding sleeve Space in end between the lower section of step and the top of center spud upper end outer step forms the hydraulic cavities 10 of sliding sleeve 8；Sliding sleeve 8 Lower port inner chamber is provided with ring cavity, and elastic lock sleeve 13 is provided with ring cavity, and elastic lock sleeve 13 is embraced in the outer of center spud 9 Week, and the inwall of elastic lock sleeve 13 is provided with box thread, the lower end periphery of sliding sleeve 8 is connected with lock tube nut 14, lock tube nut 14 Interior step is resisted against the lower section of elastic lock sleeve 13；The stage casing periphery of the short transverse of center spud 9 is provided with can be with elastic lock sleeve 13 The stopping lock tooth 9a that box thread is engaged.

Rubber cylinder pressing cap 7 limits the lower end of packing element 5, prevents the lower end of its packing element 5 from outwards expanding protrusion；When sliding sleeve 8 Hydraulic cavities 10 fluid power effect under head on packing element 5 it is up when, lock tube nut 14 is up with sliding sleeve 8, and it is suitable to push elastic lock sleeve 13 The outer wall upward sliding of center spud 9, elastic lock sleeve 13, which is provided with axial groove, makes elastic lock sleeve 13 have certain deformation energy Power, when elastic lock sleeve 13, which is gone upward to, to be engaged with stopping lock tooth 9a, will by monodirectional locking, sliding sleeve 8 can only upward packing element 5, Even if fluid power disappears, sliding sleeve 8 will not also glide release.

The bottom of central tube 2 is radially symmetrically plugged with least two blind pluggings 11, blind plugging with 10 corresponding position of hydraulic cavities 11 circumference, which is provided with, is easy to the blind plugging V-shaped groove 11b that blind plugging 11 neatly fractures, blind plugging V-shaped groove 11b bottom land and central tube 2 Inwall is concordant, and blind plugging 11 is provided with the half deep hole 11a that ecto-entad extends along blind plugging center line, and half deep hole 11a cecum is than blind plugging V Axis of the shape groove 11b closer to central tube 2；The external end head of blind plugging 11 is pushed down by blind plugging gland 12 respectively, and blind plugging gland 12 is distinguished It is screwed in the blind plugging gland screwed hole of center spud 9, blind plugging gland 12 is distributed with multiple to be communicated with half deep hole 11a of blind plugging 11 's.

After blind plugging 11 is inserted into the tube wall of central tube 2, screws on blind plugging gland 12 and compress blind plugging 11, blind plugging 11 is broken off Before, hydraulic cavities 10 and center tube cavity are obstructed, and now packer A is in the lock state, and prevent from surprisingly working during going into the well Mistake is caused to expand.After plug B is dropped down onto in blind plugging 11, drilling fluid pump is pressurized to packer working pressure, and plug B is by blind plugging 11 fracture at blind plugging V-shaped groove 11b bottom land, and the drilling fluid of center tube cavity passes through the half deep hole 11a and gland at blind plugging center Through hole 12a enters the hydraulic cavities 10 of sliding sleeve 8, and the fluid power promotion sliding sleeve 8 of hydraulic cavities 10 is up, and packing element 5 starts to expand.Plug B after Continuous come downwards to stops at annular pressure compensator C and is pressurized to packer set pressure value, and packing element 5 is expanded to maximum, is insulating Realized at layer setting.

Holding screw 15 is connected with the lower circumferential of lock tube nut 14, the inner termination of holding screw 15 is embedded in center spud In the counterbore of 9 peripheries, the lower surface supported underneath of lock tube nut 14 has locking nut 16, and locking nut 16 is screwed in center spud On 9.Screwing in holding screw 15 can be locked in lock tube nut 14 on center spud 9, prevent lock tube malfunction in transportation Make；Locking nut 16 determines the bottom dead centre of sliding sleeve 8, and anti-anti-skid sheath 8 slips.

The total length of packing element 5 is 300 ~ 350mm, and the width of setting hoop 6 is the 1/32 ~ 1/30 of packing element total length, twice setting Spacing between hoop is the 1/16 ~ 1/15 of packing element total length.As a result of reliable twice linear sealing, glue of the present utility model Tube length degree only to be conventional every 1/3~1/5 or so of device packing element length, and then can make packer entire length shorten to 1.2m with Under, thickness can be competent at completely for the setting of the thin interlayers of below 3m.

Annular pressure compensator C includes the compensator upper connecting tube 17 and compensator lower linking tube 18 that mutually spin, under compensator The inner chamber of adapter 18 is provided with level pressure set 19, and the outer wall of level pressure set 19 coordinates with the inwall gap of compensator lower linking tube 18, and level pressure The outer wall of set 19 is symmetrically plugged with two level pressure pins 20, and the external end head of level pressure pin 20 is plugged in bushing 21 respectively, bushing 21 lower surface is respectively supported on the interior step of compensator lower linking tube 18, under bushing 21, compensator upper connecting tube 17 and compensator The internal diameter of adapter 18 is equal；The circumference of level pressure pin 20, which is provided with, is easy to the level pressure pin V-shaped groove that pin neatly fractures, level pressure pin The bottom land for following closely V-shaped groove is concordant with the inwall of bushing 21；The upper end of bushing 21 is provided with up big and down small bushing horn mouth 21a, level pressure The upper end of set 19 protrudes from bushing horn mouth 21a upper limb, and level pressure covers the rim of a bowl 19a to lower recess that 19 upper port is provided with.

In setting procedure at sealing layer, plug B falls on level pressure set 19 packer A, continues to be pressurized to using small displacement Annular pressure compensator C opening pressure value, plug B pressure cut level pressure pin 20 at the bottom land of level pressure pin V-shaped groove Disconnected, because the bottom land of level pressure pin V-shaped groove is concordant with the inwall of bushing 21, after level pressure pin 20 is cut off, level pressure set 19 can Smoothly glide；Annular space below sealing layer applies additonal pressure, between compensation and increase waiting-on-cement caused by cement slurry weight loss etc. Annular space head of liquid declines.After plug B presses several times, easily there is overlap in its lower surface, and the upper end of level pressure set 19 protrudes from lining Horn mouth 21a upper limb is covered, prevents the overlap of plug B lower ends scratches from arriving bushing 21, the bushing horn mouth 21a of the upper end of bushing 21 is more Add the scratch for avoiding plug B, the rim of a bowl 19a of level pressure 19 upper ports of set just accepts plug B lower end, beneficial to plug B and level pressure Cover the combination of 19 coaxial lines.

The job step of the utility model cementing unit is as follows successively：(1), according to completion requirements, confirm that sealing layer thickness is Below 3m thin interlayer, by well-log information and theoretical calculation determine cement slurry volume, drilling well liquid measure, packer working pressure, Bruising pressure value after packer set pressure value, annular pressure compensator C opening pressure value and plug B stoppings, its middle ring Empty pressure compensator C opening pressure value is more than packer A setting more than pressure value 5MPa；(2) setting of casing string in the wellbore, The packer A of bunch tube bottom reaches the position corresponding with thin interlayer；With cementing truck to bunch tube inner chamber injection rinse every Chaotropic, rinse out the mud of the borehole wall and casing wall and loose mud cake；(4) cement mortar is injected to bunch tube inner chamber with cementing truck；To Bunch tube inner chamber is put into plug B, then promotes plug B descending with drilling fluid pump injection drilling fluid, and plug B is by the water in bunch tube Mud presses down, from the annular region at float shoe E outside sleeve pipe；(6) when plug B reaches packer A, the cement in annular space Slurry reaches the top of sealing layer；(7) drilling fluid pump is pressurized to packer working pressure, and plug B opens packer A, then glue When plug B is continued traveling downwardly to close to annular pressure compensator C, cementing truck is used to continue to be pressurized to packer set pressure with small displacement Value, makes packer A be realized in the borehole wall at sealing layer setting, and voltage stabilizing 3~5 minutes；(8) cementing truck continues to increase with small displacement Annular pressure compensator C opening pressure value is depressed into, plug B is opened annular pressure compensator C；(9) cementing truck continues with small Discharge capacity promotes plug B descending, stops when plug B comes downwards to float collar D upper surfaces, builds the pressure again to bruising pressure value, and voltage stabilizing 5 ~7 minutes；(10) cementing truck release, after confirming that the inner chamber of bunch tube is not returned, it is solidifying that spacious pressure time is continued.

Specific embodiment one：Well depth 1840m, oil overhold 1500m, oily bottom 1800m, design cement return a height of 1200m；Water injection well Water injection pressure be more than 19MPa, overflow, drilling fluid density 1.25g/cm3 occurred in drilling process, sealing layer is located at 1608.07~1611.03m, hole diameter rule, and belong to shale layer well section；Sleeve pipe nominal diameter is 5 ", use is of the present utility model Technique is cemented the well, and annular pressure compensator tripping in position is 1822.74~1823.95m, away from oil reservoir bottom about 23m, float collar Lower depth is 1832.00m, float collar and float shoe interval 11m.Determine that packer working pressure is 9MPa, packer set pressure value For 12MPa, the bruising pressure value after the opening pressure value of annular pressure compensator is 22.6MPa, plug stops is 10.5MPa.

(4) step injects cement mortar 24.53m3, averag density 1.92g/cm3 with cementing truck to bunch tube inner chamber；Step (5) (6) (7) drilling fluid 19.8m3, drilling fluid density 1.25g/cm3, relative viscosity 44 seconds are injected altogether（Flow through Marsh funnel viscosity The time of meter）；Step is (7) following until when plug comes downwards to float collar stopping, and the cement mortar for continuing injection is 2.4m3, and step is (7) Following cementing truck small displacement is with 200L/min.

It the foregoing is only the preferable possible embodiments of the utility model, non-therefore limitation patent of the present utility model Protection domain.In addition to the implementation, the utility model can also have other embodiment.It is all to use equivalent substitution or equivalent change The technical scheme to be formed is changed, is all fallen within the protection domain of the requires of the utility model.Technology of the utility model without description is special Sign can be realized by or using prior art, will not be repeated here.

Claims (10)

1. a kind of anti-channeling layer cementing unit, including the bunch tube in well, it is characterised in that the inner chamber of described sleeve pipe string is set There is the plug that can unidirectionally move downward, the circumference of the plug is provided with multiple tracks shirt rim, and the shirt rim is interior with described sleeve pipe string Wall realizes sealing, and the bottom of described sleeve pipe string is provided with packer, and the packer is corresponding with the position of the thin interlayer of well, described There is annular pressure compensator the lower end of packer by sleeve pipe connection, and the lower end of the annular pressure compensator passes through sleeve pipe connection There is float collar.

2. anti-channeling layer cementing unit according to claim 1, it is characterised in that：The packer includes top connection and center Pipe, the upper end of the top connection are provided with the box thread mutually to be spun with upper square casing, and the upper end of the central tube is screwed in top connection In the box thread of lower end；Packing element is set with the middle part of the central tube, the upper end of the packing element is embedded in packing element bearing, described Packing element bearing is sleeved on the central tube, and elasticity is provided between the top of the packing element bearing and the lower surface of the top connection Supporting mechanism, the periphery at packing element axial direction middle part are provided with twice packing element neck, setting are embedded with respectively in the packing element neck Hoop, twice setting is spaced apart between binding round, and the lower surface of the packing element is provided with hydraulic compression mechanism.

3. anti-channeling layer cementing unit according to claim 2, it is characterised in that：The elastic supporting mechanism includes being sleeved on The retainer ring and spring steel support ring of the central tube periphery, the upper end of the retainer ring are resisted against the lower end of the top connection, The lower end of the retainer ring is provided with retainer ring horn mouth, the bell-mouthed root of retainer ring and the retainer ring ring-type being recessed upwards Groove is communicated, and the upper end of the spring steel support ring is inlaid in the retainer ring annular recess, the spring steel support ring The groove that bottom is evenly distributed with multiple tracks lower ending opening makes the bottom of spring steel support ring form multiple flexible flaps, each bullet The lower end of property limb is flared out respectively.

4. anti-channeling layer cementing unit according to claim 3, it is characterised in that：The upper end of the packing element bearing is provided with upper small Big packing element bearing tapered slope down, the lower end of each flexible flaps bear against the circle in the packing element bearing tapered slope Zhou Shang, the inclination angle and the bell-mouthed inclination angle of the retainer ring of each packing element bearing tapered slope are equal；The root of each flexible flaps Portion periphery is respectively equipped with flexible flaps arc groove, and each flexible flaps arc groove is located on same circumference and is located at institute State the bell-mouthed root of retainer ring.

5. anti-channeling layer cementing unit according to claim 4, it is characterised in that：The bottom of the spring steel support ring is provided with Rubber protecting jacket, the rubber protecting jacket are covered in the periphery of each flexible flaps, the periphery of the rubber protecting jacket and institute State that the periphery of retainer ring is concordant, the upper end of the rubber protecting jacket is embedded in the retainer ring horn mouth and the flexible flaps arc In groove；The position that the rubber protecting jacket contacts with the retainer ring lower edge is provided with rubber protecting jacket annular recess.

6. anti-channeling layer cementing unit according to claim 2, it is characterised in that：The hydraulic compression mechanism includes embracing in institute The sliding sleeve of central tube periphery is stated, the top braces of the sliding sleeve are in the lower section of the packing element lower surface, the sliding sleeve upper end Nei Tai The internal perisporium of rank realizes and sealed that the upper end of the sliding sleeve is provided with sliding sleeve outer step, the sliding sleeve by O-ring and the central tube Rubber cylinder pressing cap is connected with outer step, the lower end periphery of the packing element is plugged in the rubber cylinder pressing cap；The inner chamber of the sliding sleeve Provided with center spud, the upper end of the center spud is screwed on the male thread of central tube lower end and center spud upper end outer step Periphery wall realize and seal that the lower end of the center spud is from the lower end of the sliding sleeve by the inwall of O-ring and the sliding sleeve Stretch out；Described in space in the sliding sleeve upper end between the lower section of step and the top of center spud upper end outer step is formed The hydraulic cavities of sliding sleeve；The lower port inner chamber of the sliding sleeve is provided with ring cavity, is provided with elastic lock sleeve in the ring cavity, institute Elastic lock sleeve is stated to embrace in the periphery of the center spud, and the inwall of the elastic lock sleeve is provided with box thread, under the sliding sleeve End periphery is connected with lock tube nut, and the interior step of the lock tube nut is resisted against the lower section of the elastic lock sleeve；The center connects The stage casing periphery of pipe short transverse is provided with the stopping lock tooth that can be engaged with the box thread of elastic lock sleeve.

7. anti-channeling layer cementing unit according to claim 6, it is characterised in that：The bottom of the central tube and the hydraulic pressure The corresponding position of chamber is radially symmetrically plugged with least two blind pluggings, and the circumference of the blind plugging, which is provided with, is easy to blind plugging neatly to fracture Blind plugging V-shaped groove, the bottom land of the blind plugging V-shaped groove is concordant with the inwall of the central tube, and the blind plugging is provided with ecto-entad edge Half deep hole of blind plugging center line extension, the axis of the cecum of half deep hole than the blind plugging V-shaped groove closer to the central tube； The external end head of the blind plugging is pushed down by blind plugging gland respectively, and the blind plugging gland is screwed in the blind plugging pressure of the center spud respectively In lid screwed hole, multiple gland through holes communicated with half deep hole of the blind plugging are distributed with the blind plugging gland.

8. anti-channeling layer cementing unit according to claim 7, it is characterised in that：Revolved on the lower circumferential of the lock tube nut Holding screw is connected to, the inner termination of the holding screw is embedded in the counterbore of the center spud periphery, the lock tube nut Lower surface supported underneath has locking nut, and the locking nut is screwed on the center spud.

9. anti-channeling layer cementing unit according to claim 2, it is characterised in that：The packing element total length is 300 ~ 350mm, The width of the setting hoop is the 1/32 ~ 1/30 of the packing element total length, and the spacing between twice setting hoop is total for the packing element The 1/16 ~ 1/15 of length.

10. anti-channeling layer cementing unit according to claim 2, it is characterised in that：The annular pressure compensator includes phase The compensator upper connecting tube and compensator lower linking tube mutually to spin, the inner chamber of the compensator lower linking tube are provided with level pressure set, the level pressure The inwall gap of the outer wall of set and the compensator lower linking tube coordinates, and the outer wall of level pressure set is symmetrically plugged with two level pressure Pin, the external end head of the level pressure pin are plugged in bushing respectively, and the lower surface of the bushing is respectively supported at the compensation On the interior step of device lower linking tube, the internal diameter of the bushing, compensator upper connecting tube and compensator lower linking tube is equal；The level pressure pin Circumference be provided with and be easy to the level pressure pin V-shaped groove that pin neatly fractures, bottom land and the bushing of the level pressure pin V-shaped groove Inwall it is concordant；The upper end of the bushing is provided with up big and down small bushing horn mouth, and the upper end that the level pressure covers protrudes from described The bell-mouthed upper limb of bushing, the rim of a bowl to lower recess that the upper port that the level pressure covers is provided with.