CN117189021A - Hydraulic setting cement squeezing drillable packer and operation method - Google Patents

Abstract

The invention relates to a hydraulic setting cement extrusion drillable packer and an operation method thereof. The invention can be connected with an oil pipe, a drill rod or a continuous oil pipe, can be put into a horizontal well, a highly inclined well or a vertical well, can transmit torque in the process of putting into the well, has strong resistance to meeting the blockage, is opened when being put into the well, and can automatically communicate cement squeezing pore canals without filling liquid at the lower part, is provided with a piston mechanism, is hydraulically sealed, and does not need to lift or rotate a tubular column to realize sealing of a packer; the packer is anchored bidirectionally, and the bearing capacity is strong. The invention can realize the large-displacement cement extrusion construction operation, complete the operations of setting, releasing, flushing the inner cavity of the packer, cement extrusion construction and closing the cement extrusion channel by one drilling operation, thereby saving the occupied time and labor cost of the drilling machine greatly.

Description

Hydraulic setting cement squeezing drillable packer and operation method

Technical Field

The invention relates to an underground tool for petroleum development, in particular to a hydraulic setting cement squeezing drillable packer and an operation method.

Background

Permanent or temporary plugging of the water and abandoned formations is often required during oil field development, well completion and workover. The current domestic solutions for the above operations are:

1. the packer or the gloss oil pipe is used for squeezing cement, the process is simple, but the pressure difference resistance of the cement squeezing packer is small, the reliability is low, the packer is started out too early after the cement squeezing of the packer, and the cement squeezing effect is poor; when the packer is started too late, the packer is easily solidified by cement paste, and the risk is very high; the cement squeezing time of the optical oil pipe is also not easy to control, and cement paste is easy to lie on the horizontal half section of the sleeve in a horizontal well or a highly inclined well, so that the cement paste is not easy to squeeze into a target horizon.

2. The mechanical setting tool is used for setting cement and extruding cement, the setting and extruding of the cement retainer are completed by lifting and rotating an oil pipe or a drill pipe once, but the mechanical setting tool is convenient and reliable, but has limitation in a highly-inclined well and a horizontal well, because friction between the pipe and the inner wall of a sleeve is too large, torque cannot be effectively transmitted to the mechanical setting tool below a few kilometers on the ground, the mechanical setting tool cannot be operated, and secondly, the mechanical setting tool must be lifted by a large tonnage to complete the setting of the cement retainer, so that the self weight of the pipe is large for a deep well, the setting force value of the pipe is very large, and the requirement on ground pulling equipment is very high, and the tensile load requirement on the pipe is also very high.

3. The conventional hydraulic setting tool setting cement extrusion tool can be used in diameter, inclined wells and horizontal wells, has higher reliability, but needs to take out a drilling tool after the first time pipe column is used for finishing setting a cement retainer, then go into a second time sealing insertion pipe for cement extrusion operation, wastes operation time, occupies man-hour of the drilling machine, has higher cost, and often has the phenomenon that the second time sealing insertion pipe cannot effectively switch the cement extrusion sliding sleeve of the cement retainer due to sedimentation and blockage of underground mud, sand or other falling matters in the inside of a sealed central pipe of the cement retainer during the first time pipe column and the second time cement extrusion pipe column.

4. In the hydraulic cement retainer of the pipe column, although the hydraulic setting and releasing of the pipe column are completed in one time in recent years, the sliding sleeve at the tail part of the retainer is closed due to the upward buckling and shrinkage of the pipe column and the oil pipe in the cement squeezing process, so that the cement squeezing operation cannot be completed; the slide valve is not erosion-resistant, so that the slide valve cannot be closed to cause the reverse discharge of cement paste, the problem of large-displacement cement extrusion cannot be solved, or the phenomenon that the bottom one-way ball valve is damaged by erosion caused by large-displacement cement extrusion construction, so that the reverse discharge of cement paste at the bottom cannot be prevented can be solved.

Disclosure of Invention

In order to solve the problems, the invention provides the hydraulic setting cement extrusion drillable packer and the operation method thereof, which realize the large-displacement cement extrusion construction operation, and complete the operations of setting, releasing, flushing the inner cavity of the packer, cement extrusion construction and closing the cement extrusion channel of the packer by one drilling.

The technical scheme adopted by the invention is as follows: a hydraulic setting cement extrusion drillable packer is characterized in that: the sealing device comprises a tubular column, a mandrel, an upper joint, an upper slip, an upper cone, an upper back ring, a rubber cylinder, a lower back ring, a lower cone, a lower slip, a piston mechanism, a guide valve body, a sealing slide valve, a sealing ball and a plug, wherein the mandrel is sleeved outside the tubular column, and the upper joint, the upper slip, the upper cone, the upper back ring, the rubber cylinder, the lower back ring, the lower cone, the lower slip, the piston mechanism and the guide valve body are sequentially sleeved on the mandrel from top to bottom; the upper end of the upper joint is fixedly connected with the tubular column, a first shearing pin is arranged between the upper joint and the sleeve, and the lower end of the upper joint is fixedly connected with the mandrel; the upper cone and the lower cone are fixedly connected with the mandrel; the upper back ring is connected with the mandrel through a first skin rolling pin, and the lower back ring is connected with the mandrel through a second skin rolling pin;

the piston mechanism comprises a thrust piston and a piston cylinder sleeve, one end of the thrust piston is arranged in a cavity of the piston cylinder sleeve, and the other end of the thrust piston is abutted against the lower slip; a second shearing pin is arranged between the thrust piston and the piston cylinder sleeve, a lock ring is arranged between the thrust piston and the mandrel, a cavity of the piston cylinder sleeve passes through the mandrel and the tubular column to be communicated with a central hole of the tubular column, and the piston cylinder sleeve is fixedly connected with the mandrel;

the upper end of the guide valve body is fixedly connected with the mandrel, and a plug is arranged in a shaft hole at the lower end of the guide valve body; the sealing slide valve is arranged in the guide valve body, the sealing slide valve is provided with a sealing slide valve through hole, the guide valve body is provided with a guide valve body through hole matched with the sealing slide valve through hole, and the inner channel of the guide valve body is communicated with the outside through the sealing slide valve through hole and the guide valve body through hole; the tail end of the elastic claw of the sealing slide valve is clamped in a groove at the lower end of the pipe column, and a gap for releasing the elastic claw is arranged between the pipe column and the guide valve body; the lower extreme is equipped with the ball seat in the tubular column centre bore, be equipped with the third between ball seat and the tubular column and cut the pin, the setting ball sets up in the ball seat.

Preferably, the tubular column comprises an uphole joint, a sealing connecting rod and a switch joint which are sequentially arranged from top to bottom, wherein the uphole joint is fixedly connected with the upper joint, and a first shearing pin is arranged between the uphole joint and the upper joint; the upper end of the sealing connecting rod is fixedly connected with the upper joint of the well feeding, and the lower end of the sealing connecting rod is fixedly connected with the switch joint; the piston cylinder sleeve cavity is communicated with the tubular column center hole through the mandrel via hole and the switch joint via hole; the ball seat is arranged at the lower end of the central hole of the switch joint.

Preferably, the connection part of the well-conveying upper joint and the sealing connecting rod is provided with a vulcanization sealing ring and a third sealing ring, a seventh sealing ring and a ninth sealing ring are arranged between the switch joint and the mandrel, and an eleventh sealing ring is arranged between the switch joint and the ball seat.

Preferably, the upper end of the inner hole of the upper joint of the well is provided with connecting threads, the outer circular surface is uniformly provided with countersunk milling grooves along the axial direction, and the countersunk milling grooves are matched with the convex ribs in the inner hole of the upper joint.

Preferably, the outer circular surfaces of the upper slips and the lower slips are respectively provided with wicker-shaped sawteeth which are 30 degrees away from the horizontal direction.

Preferably, a fourth sealing ring and a fifth sealing ring are arranged between the thrust piston and the piston cylinder sleeve, and a sixth sealing ring is arranged between the piston cylinder sleeve and the mandrel.

Preferably, a first sealing ring is arranged between the upper joint and the mandrel.

Preferably, a retaining ring and a second sealing ring are arranged between the rubber cylinder and the mandrel.

Preferably, an eighth sealing ring is arranged between the guide valve body and the mandrel, a twelfth sealing ring is arranged between the guide valve body and the sealing slide valve, and a thirteenth sealing ring is arranged between the guide valve body and the plug.

The application method of the hydraulic setting type cement extrusion drillable packer is characterized by comprising the following steps of: the method comprises the following steps:

setting process: after the packer is lowered to a designated position, the ball is thrown and pressed, liquid flows into a cavity of a piston cylinder sleeve after passing through a switch joint through hole and a mandrel through hole, the liquid pushes a thrust piston to generate upward movement trend, a second shearing pin is sheared, the thrust piston is upwards extruded with a locking ring, and when the thrust reaches the radial shearing limit strength of a first rolling pin and a second rolling pin, the thrust piston is broken; continuing to move, when the breaking limit force value of the upper slips is reached, the upper slips break and are anchored on the inner wall of the sleeve, meanwhile, the upper back ring and the lower back ring are radially contracted and expanded after being subjected to radial component forces of the upper cone, the lower cone and the inclined planes of the end faces of the rubber cylinder, and meanwhile, the rubber cylinder is axially extruded to generate radial deformation and is tightly attached to the inner wall of the sleeve, so that sealing is realized, and upper fluid and lower fluid are blocked; the lower slips are opened and anchored simultaneously, the rubber cylinder is prevented from retracting, and the locking ring slides towards the upper part of the mandrel simultaneously and is meshed with the sawtooth threads on the outer surface of the mandrel, so that the setting load is further locked; continuously increasing the hydraulic pressure until the ball seat is subjected to a downward shearing force value enough to shear the third shearing pin, at the moment, the ball seat is knocked down, the setting ball and the ball seat are in downward contact with the upper end face of the plug, and at the moment, the whole setting process is completed;

releasing process: the pipe column is lifted up, the upper slip is anchored on the sleeve after being split, the upper joint of the well is lifted up and the upper joint generates axial shearing action to shear the first shearing pin, the whole pipe column is separated from the packer, at the moment, the elastic claw of the sealing slide valve moves upwards after receiving lifting force at the groove at the lower side of the switch joint, and the liquid outlet channel which leads to the side surface of the valve body is closed;

and (3) back-inserting and squeezing cement: the pipe column is inserted back into the inner cavity of the mandrel, the external vulcanized rubber of the vulcanized sealing ring and the inner surface of the mandrel realize interference extrusion sealing, and the fluid at the lower part is prevented from channeling to the outer side of the upper part of the pipe column; meanwhile, the outer circular surface of the extruded and deformed rubber cylinder and the inner wall of the sleeve generate extrusion stress, so that liquid isolation on the upper side and the lower side of the rubber cylinder is realized, and the retaining ring and the second sealing ring play a role in filling in the middle inner hole space of the extruded and deformed rubber cylinder;

in the cement back-plugging and squeezing process, if the sealing slide valve cannot be normally opened and the ground has a high-pressure blocking phenomenon, judging that sundries fill the space where the sealing slide valve moves downwards, at the moment, lifting the pipe column to a certain height at the top of the packer, starting to wash sundries or silt at the bottom of the packer, then smoothly opening the sealing slide valve by reinserting the pipe column, and communicating the sealing slide valve with a cement squeezing channel of the guide valve body to carry out cement squeezing operation again;

and (3) a pipe column removing process: after the cement extrusion is finished, the pipe column is directly lifted, the separation between the pipe column and the packer can be completed, and meanwhile, the tail sealing slide valve is closed, so that the liquid isolation of the unset cement paste at the tail of the packer is ensured.

The invention can be connected with any one of an oil pipe, a drill pipe or a continuous oil pipe to be put into a horizontal well, a highly inclined well or a vertical well, the well condition and the running mode are not limited, the torque can be transmitted in the running process, the resistance to resistance is strong, a slide valve is opened during running, a cement squeezing pore canal is automatically communicated, the liquid is not required to be filled at the lower part, a piston mechanism is arranged, the hydraulic setting is realized, and the pipe column is not required to be pulled or rotated to realize the setting of a packer; the packer is anchored bidirectionally, the bearing capacity is high, the elastic claw and the cement squeezing pore canal on the sealing slide valve are relatively independent, cement paste cannot pass through the side surface of the elastic claw, the elastic claw cannot be broken by liquid to cause the risk of reverse spitting of the cement paste which cannot be closed, and the large-displacement cement squeezing process is met; the tubular column shrinkage caused by pumping pressure is avoided in the cement extrusion process, the sliding valve is closed, so that high-pressure cement extrusion operation cannot be continued, parts are made of easy-drilling materials, the tail part is made of an anti-drilling structure, and the drilling type no-idling phenomenon exists. The invention can realize the large-displacement cement extrusion construction operation, complete the operations of setting, releasing, flushing the inner cavity of the packer, cement extrusion construction and closing the cement extrusion channel by one drilling operation, thereby saving the occupied time and labor cost of the drilling machine greatly.

Drawings

FIG. 1 is a schematic diagram of a hydraulic setting cement extrusion drillable packer of the present invention;

FIG. 2 is a schematic diagram of a well entry state;

FIG. 3 is a schematic view of a ball striking and setting state;

FIG. 4 is a schematic view of tee shot;

FIG. 5 is a schematic illustration of a lift string disengaged from a packer;

FIG. 6 is a schematic diagram of a string of pipe inserted back and running out of a cementing operation;

FIG. 7 is a schematic view showing the completion of the cement squeezing operation by lifting up the pipe string;

FIG. 8 is a schematic illustration of the configuration of an uphole sub;

FIG. 9 is a schematic view of the structure of the upper joint;

FIG. 10 is a schematic view of the structure of the seal spool valve;

FIG. 11 is a schematic view of the structure of the pilot valve body;

FIG. 12 is a schematic structural view of a plug;

FIG. 13 is a schematic view of the structure of the switch connector;

in the figure: 1. an uphole joint; 11. sinking milling groove; 2. an upper joint; 21. convex ribs; 3. a first shear pin; 4. a first seal ring; 5. a first set screw; 6. an upper slip; 7. a mandrel; 71. a mandrel via hole; 8. an upper cone; 9. a first skin rolling pin; 10. an upper outer back ring; 11. an upper inner back ring; 12. a rubber cylinder; 13. a retention ring; 14. a second seal ring; 15. a lower inner back ring; 16. a lower outer back ring; 17. a second skin rolling pin; 18. a lower cone; 19. vulcanizing the sealing ring; 20. a third seal ring; 21. a lower slip; 22. sealing the connecting rod; 23. a locking ring; 24. a second shear pin; 25. a thrust piston; 26. a piston cylinder sleeve; 27. a fourth seal ring; 28. a fifth seal ring; 29. a sixth seal ring; 30. a switch joint; 301. a switch joint via; 302. a groove; 31. a second set screw; 32. a seventh seal ring; 33. an eighth seal ring; 34. a ninth seal ring; 35. a pilot valve body; 351. a guide valve body via hole; 352. positioning holes; 36. a positioning pin; 37. a tenth seal ring; 38. setting ball; 39. an eleventh seal ring; 40. a third shear pin; 41. a ball seat; 42. a twelfth seal ring; 43. sealing the slide valve; 431. sealing the slide valve via hole; 432. an elastic claw; 44. a thirteenth seal ring; 45. a third set screw; 46. a plug; 00. a sleeve; 47. a gap.

Detailed Description

The following description of the embodiments of the present invention will be made apparent and fully in view of the accompanying drawings, in which some, but not all embodiments of the invention are shown. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

As shown in fig. 1-13, the hydraulic setting cement extrusion drillable packer of the invention is characterized in that: the pipe column comprises a pipe column, a mandrel 7, an upper joint 2, an upper slip 6, an upper cone 8, an upper back ring (consisting of an upper outer back ring 10 and an upper inner back ring 11), a rubber cylinder 12, a lower back ring (consisting of a lower inner back ring 15 and a lower outer back ring 16), a lower cone 18, a lower slip 21, a piston mechanism, a guide valve body 35, a sealing slide valve 43, a setting ball 38 and a plug 46, wherein the mandrel 7 is sleeved outside the pipe column, and the upper joint 2, the upper slip 6, the upper cone 8, the upper back ring, the rubber cylinder 12, the lower back ring, the lower cone 18, the lower slip 21, the piston mechanism and the guide valve body 35 are sequentially sleeved on the mandrel 7 from top to bottom; the upper end of the upper joint 2 is fixedly connected with the tubular column, a first shearing pin 3 is arranged between the upper joint 2 and the sleeve, and the lower end of the upper joint 2 is fixedly connected with a mandrel 7; the upper cone 8 and the lower cone 18 are fixedly connected with the mandrel 7; the upper back ring is connected with the mandrel 7 through a first skin rolling pin 9, and the lower back ring is connected with the mandrel 7 through a second skin rolling pin 17.

The piston mechanism comprises a thrust piston 25 and a piston cylinder sleeve 26, one end of the thrust piston 25 is arranged in a cavity of the piston cylinder sleeve 26, and the other end of the thrust piston is abutted against the lower slip 21; a second shear pin 24 is arranged between the thrust piston 25 and the piston cylinder sleeve 26, a lock ring 23 is arranged between the thrust piston 25 and the mandrel 7, a cavity of the piston cylinder sleeve 26 penetrates through the mandrel 7 and the tubular column to be communicated with a central hole of the tubular column, and the piston cylinder sleeve 26 is fixedly connected with the mandrel 7.

The upper end of the guide valve body 35 is fixedly connected with the mandrel 7, and a plug 46 is arranged in a shaft hole at the lower end; the sealing slide valve sleeve 43 is arranged in the guiding valve body 35, the sealing slide valve 43 is provided with a sealing slide valve through hole 431, the guiding valve body 35 is provided with a guiding valve through hole 351 matched with the sealing slide valve through hole 431, and an internal channel of the guiding valve body 35 passes through the sealing slide valve through hole 431 and the guiding valve through hole 351 to be communicated with the outside; the tail end of the elastic claw 432 of the sealing slide valve 43 is clamped in the groove 302 at the lower end of the pipe column, and a gap 47 for releasing the elastic claw 432 is arranged between the pipe column and the guide valve body 35; a ball seat 41 is provided at the lower end in the central bore of the string, a third shear pin 40 is provided between the ball seat 41 and the string, and a setting ball 38 is provided in the ball seat 41.

In the embodiment, the tubular column comprises an uphole joint 1, a sealing connecting rod 22 and a switch joint 30 which are sequentially arranged from top to bottom, wherein the uphole joint 1 is fixedly connected with the uphole joint 2, and a first shearing pin 3 is arranged between the uphole joint 1 and the uphole joint 2; the upper end of the sealing connecting rod 22 is fixedly connected with the uphole joint 1, and the lower end is fixedly connected with the switch joint 30; the switch joint 30 is provided with a switch joint via hole 301, the mandrel 7 is provided with a mandrel via hole 71 correspondingly matched with the switch joint via hole 301, and the cavity of the piston cylinder sleeve 26 is communicated with the tubular column center hole through the mandrel via hole 71 and the switch joint via hole 301; a ball seat 41 is provided at the lower end of the central hole of the switch joint 30 with a third shear pin 40 therebetween.

In this embodiment, the upper side of the tail connecting thread of the sealing connecting rod 22 is provided with a vulcanized sealing ring 19 and a third sealing ring 20, the tail thread is connected with a switch joint 30, the tail of the switch joint 30 is connected with an eleventh sealing ring 39 and a ball seat 41 through a third shear pin 40, and a setting ball 38 is arranged in an inner hole on the upper side of the ball seat 41. The setting ball 38 and ball seat 41 form a seal under hydraulic pressure setting, temporarily blocking the lower flow path, allowing fluid to enter the piston mechanism, and achieving the anchoring and sealing of the packer.

In the embodiment, the outer circle surfaces of the upper slips 6 and the lower slips 21 are respectively provided with wicker-shaped saw teeth which are 30 degrees away from the horizontal direction, and the surfaces of the upper slips and the lower slips are subjected to a surface high-frequency quenching process, so that the hardness is high, and the powerful wedge-shaped inner wall of the sleeve is favorable for forming an anchor after being stressed; the upper slips 6 and the lower slips 21 receive upward and downward anchoring thrust, respectively.

In this embodiment, the rubber cylinder 12 is radially deformed after being compressed, and the rubber on the deformed outer circle and the inner wall of the sleeve 00 form extrusion stress, so as to seal the oil sleeve annulus, and meanwhile, the inner back ring and the outer back ring are radially deformed to be closely attached to the inner wall of the sleeve, so that the rubber on the upper side and the lower side of the deformed rubber cylinder 12 is prevented from being damaged by pressure.

In this embodiment, a second shear pin 24 is disposed between a thrust piston 25 and a piston cylinder sleeve 26, a fourth seal ring 27 and a fifth seal ring 28 are respectively installed on the inner side and the outer side of the tail portion of the lower side of the thrust piston 25, the inner wall of the lower side of the piston cylinder sleeve 26 is threaded and connected with the outer thread of the tail portion of the mandrel 7, and the sixth seal ring 29 is installed in the inner circle seal groove of the lower side of the piston cylinder sleeve 26.

In this embodiment, as shown in fig. 11, the guiding valve body 35 is connected with the external thread at the tail part of the lower side of the mandrel 7, the second set screw 31 is fixed on the thread at the upper side of the guiding valve body 35, the middle part is provided with a positioning hole 352 and a tenth sealing ring 37, and the positioning hole 352 is internally provided with a positioning pin 36 for mounting and positioning between the guiding valve body 35 and the sealing slide valve 43; the twelfth sealing ring 42 is arranged in the guide valve body 35, rib plates and guide valve body through holes 351 are uniformly distributed on the outer circle of the lower side, the tail part is provided with internal threads and is connected with external threads of the plug (46), and the thread ending part is provided with the thirteenth sealing ring 44 and a third set screw 45.

In this embodiment, the inner hole on the upper side of the upper joint 1 of the well is provided with a conventional oil pipe female thread, as shown in fig. 8, the outer circle surface is provided with six countersunk grooves 11 uniformly distributed, the countersunk grooves 11 are matched with slope surface ribs 21 with 30-degree chamfer angles on the upper side of the upper joint 2 in fig. 2, and torque can be transmitted in the process of entering the well of the pipe column, so that the pipe column can more easily advance in a highly-inclined well or a horizontal well; six evenly distributed settlement holes are arranged in the middle part and used for installing the shearing head part of the first shearing pin 3 and overcoming the tubular column shrinkage force generated when the packer is hydraulically set, and simultaneously, the temporary connection between the tubular column and the packer and the disconnection function after setting are provided.

In this embodiment, the rubber cylinder 12 is extruded into an ellipse along the mandrel 7 through the upper cone 8 and the lower cone 18 in opposite directions, and forms contact extrusion stress with the inner wall of the sleeve 00, so as to realize the packing of an oil sleeve annulus, and the upper back ring and the lower back ring slide and relax radial deformation on 45-degree inclined plane extrusion component forces on the sides of the upper cone 8 and the lower cone 18 respectively and are tightly attached to the inner wall of the sleeve, so that the outer circular shoulders on the upper side and the lower side of the pressurized rubber cylinder 12 are protected, the rubber body is prevented from extrusion damage, and high-pressure differential sealing is realized.

Referring to fig. 13, in this embodiment, two waist-shaped through hole milling grooves (i.e., switch joint via holes 301) are uniformly distributed in the middle of the switch joint 30, and the switch joint via holes 301 and a circular liquid inlet hole (i.e., a mandrel via hole 71) at the tail of the lower side of the mandrel 7 form a liquid inlet channel when the packer is set; the inner hole at the upper end of the thrust piston 25 is provided with a sawtooth thread, the sawtooth thread is meshed with the lock ring 23, when pressure enters the inner cavity of the piston cylinder sleeve 26, the thrust piston 25 moves upwards to drive the lock ring 23 to slide upwards together and gradually mesh with the sawtooth thread on the outer circular surface of the mandrel 7, so that the locking and anti-withdrawal functions are realized, and the sealing and anchoring can be realized better; meanwhile, the second shear pin 24 temporarily fixes the thrust piston 25 and the piston cylinder sleeve 26 within a certain shear force value range, so that the phenomenon of pre-setting of the packer caused by early starting of the piston mechanism due to pressure difference formed by pressure excitation in the pipe column running process is prevented.

In this embodiment, the outer circle of the guiding valve body 35 is provided with a seal formed by the tenth sealing ring 37 and the positioning pin 36, the protruding portion at the tail of the positioning pin 36 is opposite to three milling grooves uniformly distributed on the outer circle of the upper end of the sealing slide valve 43, so that a liquid outlet channel (i.e. a sealing slide valve through hole 431) on the outer circle surface of the sealing slide valve 43 is aligned with a liquid outlet channel (i.e. a guiding valve through hole 351) on the lower side of the guiding valve body 35 in the circumferential direction, the liquid outlet smoothness during cement extrusion is ensured to the greatest extent, the liquid outlet channel is relatively independent from an elastic claw 432 on the upper side of the sealing slide valve 43, fluid cannot pass through the elastic claw 432 of the sealing slide valve 43, and then the elastic claw 432 cannot be flushed by fluid, so that the elastic claw 432 cannot be damaged, the situation that the sealing slide valve cannot be reset due to the fact that the pipe column is pulled out after the cement extrusion is finished, and then the phenomenon of anti-extrusion caused by the sealing slide valve 43 cannot be effectively closed is avoided.

The drillable packer assembly sequence of the invention is as follows: the lower side thread of the upper joint 2 is connected with the upper side thread of the mandrel 7, and is provided with a first sealing ring 4, and a first set screw 5 is tightened; loading an upper slip 6 from the lower side, loading an upper cone 8, drilling a certain depth on a mandrel 7 through a skin rolling pin hole of the upper cone 8, and tamping a first skin rolling pin 9; a first outer back ring 10 and a first inner back ring 11 are arranged in the inner back ring; a rubber hammer is used for loading a bearing ring 13 and a second sealing ring 14 into a rubber cylinder 12, and then the whole is loaded into the middle part of a mandrel 7 and combined and attached with an inner back ring and an outer back ring; then the second inner back ring 15 and the second outer back ring 16 are installed, the lower cone 18 is installed in the same mode, drills are matched in the rolling skin pin holes of the mandrel 7 and the lower cone 18, the second rolling skin pin 17 is knocked in, the lower slips 21 are installed, the lock ring 23 is screwed into the sawtooth threads in the inner hole at the upper side of the thrust piston 25, the fourth seal ring 27 and the fifth seal ring 28 are respectively installed into the seal ring grooves of the inner and outer circular surfaces at the lower end of the thrust piston 25, and then sleeved on the mandrel 7, and the sixth seal ring 29 is knocked in to the mandrel 7 from the lower side and is connected with the internal threads; the twelfth sealing ring 42 is installed in the upper sealing groove of the sealing slide valve 43, the tenth sealing ring 37 is installed on the locating pin 36 and screwed into the locating hole 352 of the guiding valve body 35, the sealing valve body 43 is knocked in from the upper side of the guiding valve body 35 until the lower side step of the elastic claw 352 contacts the inner hole step of the guiding valve body 35, the milling groove opening phase of the sealing slide valve (43) is aligned with the sinking tail end of the plug (36), so that the sealing slide valve through hole 431 is aligned with the guiding valve body through hole 351, the eighth sealing ring 33 is installed in the upper inner hole sealing ring groove of the guiding valve body 35 and connected with the tail thread of the mandrel 7, and the second set screw 31 is tightened; installing the thirteenth sealing ring 44 into the sealing ring groove at the upper end of the plug 46 and connecting the thirteenth sealing ring to the inner hole thread of the tail part of the lower side of the guide valve body 35, and tightening the third set screw 45 until the drillable packer assembly is installed; then, connecting the external thread on the lower side of the uphole joint 1 with the internal thread on the upper side of the sealing connecting rod 22, installing the vulcanized sealing ring 19 and the third sealing ring 20 on the smooth outer circular surface on the lower side of the sealing connecting rod 22, connecting the vulcanized sealing ring 19 and the internal thread on the upper end of the connection switch joint 30, installing the eleventh sealing ring 39 into the inner hole on the lower side of the switch joint 30, installing the third shearing pin 40, finding the setting ball 38 for standby, and completing the connection of the running tool assembly (i.e. a tubular column) until the completion; finally, the feeding pipe column is inserted into the inner hole of the mandrel 7, the phase is found, the slope milling groove 11 of the feeding uphole joint 1 is attached to the convex rib 21 of the inner hole on the upper side of the uphole joint 2, and finally, the first shearing pin 3 is installed, so that the whole tool string is installed completely and is in a state of waiting to enter a well.

The working principle of the scheme is as follows:

setting process: after the packer is lowered to a designated position, the ground ball is thrown and pressed, liquid flows into a cavity of a piston cylinder sleeve 26 after passing through a switch joint through hole 301 and a mandrel through hole 71, a thrust piston 25 generates upward movement trend, a second shearing pin 24 is sheared, the second shearing pin 24 is pushed to the upper end by a locking ring 23, when the thrust reaches the radial shearing limit strength of a first rolling pin 9 and a second rolling pin 17, the second shearing pin breaks, then the second shearing pin continues to move, when the breaking limit strength of an upper slip 6 is reached, the upper slip 6 breaks and is anchored on the inner wall of a sleeve, and simultaneously an upper back ring and a lower back ring are radially contracted when being respectively subjected to radial component forces at 45-degree slopes of the end surfaces of an upper cone 8, a lower cone 18 and a rubber cylinder 12, so that the shoulder of the rubber cylinder 12 which is axially compressed is prevented from being squeezed and turned over, and pressure bearing is better realized; simultaneously, the rubber cylinder 12 is axially extruded to generate radial deformation, the outer circular surface is oval and is tightly attached to the inner wall of the sleeve 00, so that sealing is realized, and up-and-down fluid is blocked; the lower slips 21 are simultaneously opened and anchored to prevent the rebound force of the retraction of the rubber cylinder 12, the locking ring 23 simultaneously slides towards the upper part of the mandrel 7 and is meshed with the sawtooth threads on the outer surface of the mandrel 7, and the locking setting load is improved; the hydraulic pressure continues to rise until the ball seat 41 is subjected to a downward shear force of sufficient magnitude to shear the third shear pin 40, at which point the ball seat 41 is knocked down and the setting ball 38 and ball seat 41 descend into contact with the upper end face of the plug 40, at which point the entire setting process is completed.

Releasing process: the pipe column is lifted, and the upper slips 6 are anchored on the casing 00 after being cracked, so that upward axial movement is limited, at the moment, the upper well joint 1 and the upper joint 2 generate axial shearing action, the first shearing pin 3 is sheared, and the whole pipe column is separated from the packer; at this time, the elastic claw 432 of the seal spool 43 moves upward after receiving the lifting force at the concave surface 302 on the lower side of the switch joint 30, closing the liquid outlet passage to the side of the valve body 35.

And (3) back-inserting and squeezing cement: the pipe column is inserted back into the inner cavity of the mandrel 7, the outer vulcanized rubber of the vulcanized sealing ring 19 and the inner surface of the mandrel realize interference extrusion sealing, so that lower fluid is prevented from channeling to the outer side of the upper part of the feeding tool, meanwhile, the outer circular surface of the extruded and deformed rubber cylinder 12 and the inner wall of the sleeve generate larger contact extrusion stress, the liquid isolation of the upper side and the lower side of the rubber cylinder 12 is realized, and the retention ring 13 and the second sealing ring 14 play a role in filling in the middle inner hole space after the extrusion deformation of the rubber cylinder 12, so that the sealing is more reliable and the bearing pressure is higher;

if the sealing slide valve 43 cannot be normally opened in the back insertion process, if the ground is in a high-pressure holding phenomenon, it is judged that sundries fill up the space where the sealing slide valve 43 moves downwards, at the moment, the pipe column is required to be lifted upwards to be pulled out of the top of the drillable packer by about 1 meter, sundries or silt at the bottom of the packer begin to be washed away in a large displacement mode, the sundries are washed away, then the sealing slide valve 43 can be smoothly opened after being inserted again, the sealing slide valve 43 and a cement squeezing channel of the guiding valve body 35 are communicated, and cement squeezing operation is performed again.

In the cement extrusion process, cement slurry only passes through the 45-degree inclined duct of the sealing slide valve 43 and cannot flow through the elastic claws 432 on the upper side to mill a gap, so that the three elastic claws 432 of the sealing slide valve 43 cannot be damaged, when the pipe column is lifted, the clamping joint 30 can smoothly drive the sealing slide valve 43 to move upwards to close the cement extrusion channel, and the unset cement slurry is blocked on the lower side of the packer, so that the convenience of safely lifting the pipe column is realized.

Meanwhile, in the cement squeezing process, fluid only flows into the cement squeezing channel of the bottom guide valve body 35 and the cavity of the piston cylinder sleeve 26, the thrust generated by the thrust piston 25 only compresses the slip anchoring system of the packer and the sealing extrusion system more tightly and stably, and the pipe column is not jacked out upwards like other pipe column cement retainers, so that the pipe column moves upwards, and the cement squeezing channel of the tail sealing slide valve 43 and the guide valve body 35 is closed.

And (3) a pipe column removing process: after the cement extrusion is finished, the pipe column is directly lifted, the separation between the pipe column and the packer can be completed, and meanwhile, the tail sealing slide valve 43 is closed, so that the liquid isolation of the unset cement paste at the tail of the packer is ensured.

Here, it should be noted that the description of the above technical solution is exemplary, and the present specification may be embodied in different forms and should not be construed as being limited to the technical solution set forth herein. Rather, these descriptions will be provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art. Furthermore, the technical solution of the invention is limited only by the scope of the claims.

Finally, it should be noted that the above embodiments are merely representative examples of the present invention. Obviously, the invention is not limited to the above-described embodiments, but many variations are possible. Any simple modification, equivalent variation and modification of the above embodiments according to the technical substance of the present invention should be considered to be within the scope of the present invention.

Claims (10)

1. A hydraulic setting cement extrusion drillable packer is characterized in that: the sealing device comprises a tubular column, a mandrel, an upper joint, an upper slip, an upper cone, an upper back ring, a rubber cylinder, a lower back ring, a lower cone, a lower slip, a piston mechanism, a guide valve body, a sealing slide valve, a sealing ball and a plug, wherein the mandrel is sleeved outside the tubular column, and the upper joint, the upper slip, the upper cone, the upper back ring, the rubber cylinder, the lower back ring, the lower cone, the lower slip, the piston mechanism and the guide valve body are sequentially sleeved on the mandrel from top to bottom; the upper end of the upper joint is fixedly connected with the tubular column, a first shearing pin is arranged between the upper joint and the sleeve, and the lower end of the upper joint is fixedly connected with the mandrel; the upper cone and the lower cone are fixedly connected with the mandrel; the upper back ring is connected with the mandrel through a first skin rolling pin, and the lower back ring is connected with the mandrel through a second skin rolling pin;

the piston mechanism comprises a thrust piston and a piston cylinder sleeve, one end of the thrust piston is arranged in a cavity of the piston cylinder sleeve, and the other end of the thrust piston is abutted against the lower slip; a second shearing pin is arranged between the thrust piston and the piston cylinder sleeve, a lock ring is arranged between the thrust piston and the mandrel, a cavity of the piston cylinder sleeve passes through the mandrel and the tubular column to be communicated with a central hole of the tubular column, and the piston cylinder sleeve is fixedly connected with the mandrel;

the upper end of the guide valve body is fixedly connected with the mandrel, and a plug is arranged in a shaft hole at the lower end of the guide valve body; the sealing slide valve is arranged in the guide valve body, the sealing slide valve is provided with a sealing slide valve through hole, the guide valve body is provided with a guide valve body through hole matched with the sealing slide valve through hole, and the inner channel of the guide valve body is communicated with the outside through the sealing slide valve through hole and the guide valve body through hole; the tail end of the elastic claw of the sealing slide valve is clamped in a groove at the lower end of the pipe column, and a gap for releasing the elastic claw is arranged between the pipe column and the guide valve body; the lower extreme is equipped with the ball seat in the tubular column centre bore, be equipped with the third between ball seat and the tubular column and cut the pin, the setting ball sets up in the ball seat.

2. The hydraulic setting cement extrusion drillable packer as defined in claim 1, wherein: the tubular column comprises a well-conveying upper joint, a sealing connecting rod and a switch joint which are sequentially arranged from top to bottom, wherein the well-conveying upper joint is fixedly connected with the upper joint, and a first shearing pin is arranged between the well-conveying upper joint and the upper joint; the upper end of the sealing connecting rod is fixedly connected with the upper joint of the well feeding, and the lower end of the sealing connecting rod is fixedly connected with the switch joint; the piston cylinder sleeve cavity is communicated with the tubular column center hole through the mandrel via hole and the switch joint via hole; the ball seat is arranged at the lower end of the central hole of the switch joint.

3. The hydraulic setting cement extrusion drillable packer as defined in claim 2, wherein: the joint of the well-conveying upper joint and the sealing connecting rod is provided with a vulcanized sealing ring and a third sealing ring, a seventh sealing ring and a ninth sealing ring are arranged between the switch joint and the mandrel, and an eleventh sealing ring is arranged between the switch joint and the ball seat.

4. The hydraulic setting cement extrusion drillable packer as defined in claim 2, wherein: the upper end of the inner hole of the upper joint of the well is provided with connecting threads, the outer circular surface is uniformly provided with countersink milling grooves along the axial direction, and the countersink milling grooves are matched with convex ribs in the inner hole of the upper joint.

5. The hydraulic setting cement extrusion drillable packer as defined in claim 1, wherein: the outer circle surfaces of the upper slips and the lower slips are respectively provided with wicker-shaped saw teeth which are 30 degrees away from the horizontal direction.

6. The hydraulic setting cement extrusion drillable packer as defined in claim 1, wherein: a fourth sealing ring and a fifth sealing ring are arranged between the thrust piston and the piston cylinder sleeve, and a sixth sealing ring is arranged between the piston cylinder sleeve and the mandrel.

7. The hydraulic setting cement extrusion drillable packer as defined in claim 1, wherein: a first sealing ring is arranged between the upper joint and the mandrel.

8. The hydraulic setting cement extrusion drillable packer as defined in claim 1, wherein: a retaining ring and a second sealing ring are arranged between the rubber cylinder and the mandrel.

9. The hydraulic setting cement extrusion drillable packer as defined in claim 1, wherein: an eighth sealing ring is arranged between the guide valve body and the mandrel, a twelfth sealing ring is arranged between the guide valve body and the sealing slide valve, and a thirteenth sealing ring is arranged between the guide valve body and the plug.

10. A hydraulic setting type cement squeezing drillable packer operation method is characterized in that: the method comprises the following steps:

setting process: after the packer is lowered to a designated position, the ball is thrown and pressed, liquid flows into a cavity of a piston cylinder sleeve after passing through a switch joint through hole and a mandrel through hole, the liquid pushes a thrust piston to generate upward movement trend, a second shearing pin is sheared, the thrust piston is upwards extruded with a locking ring, and when the thrust reaches the radial shearing limit strength of a first rolling pin and a second rolling pin, the thrust piston is broken; continuing to move, when the breaking limit force value of the upper slips is reached, the upper slips break and are anchored on the inner wall of the sleeve, meanwhile, the upper back ring and the lower back ring are radially contracted and expanded after being subjected to radial component forces of the upper cone, the lower cone and the inclined planes of the end faces of the rubber cylinder, and meanwhile, the rubber cylinder is axially extruded to generate radial deformation and is tightly attached to the inner wall of the sleeve, so that sealing is realized, and upper fluid and lower fluid are blocked; the lower slips are opened and anchored simultaneously, the rubber cylinder is prevented from retracting, and the locking ring slides towards the upper part of the mandrel simultaneously and is meshed with the sawtooth threads on the outer surface of the mandrel, so that the setting load is further locked; continuously increasing the hydraulic pressure until the ball seat is subjected to a downward shearing force value enough to shear the third shearing pin, at the moment, the ball seat is knocked down, the setting ball and the ball seat are in downward contact with the upper end face of the plug, and at the moment, the whole setting process is completed;

releasing process: the pipe column is lifted up, the upper slip is anchored on the sleeve after being split, the upper joint of the well is lifted up and the upper joint generates axial shearing action to shear the first shearing pin, the whole pipe column is separated from the packer, at the moment, the elastic claw of the sealing slide valve moves upwards after receiving lifting force at the groove at the lower side of the switch joint, and the liquid outlet channel which leads to the side surface of the valve body is closed;

and (3) back-inserting and squeezing cement: the pipe column is inserted back into the inner cavity of the mandrel, the external vulcanized rubber of the vulcanized sealing ring and the inner surface of the mandrel realize interference extrusion sealing, and the fluid at the lower part is prevented from channeling to the outer side of the upper part of the pipe column; meanwhile, the outer circular surface of the extruded and deformed rubber cylinder and the inner wall of the sleeve generate extrusion stress, so that liquid isolation on the upper side and the lower side of the rubber cylinder is realized, and the retaining ring and the second sealing ring play a role in filling in the middle inner hole space of the extruded and deformed rubber cylinder;

in the cement back-plugging and squeezing process, if the sealing slide valve cannot be normally opened and the ground has a high-pressure blocking phenomenon, judging that sundries fill the space where the sealing slide valve moves downwards, at the moment, lifting the pipe column to a certain height at the top of the packer, starting to wash sundries or silt at the bottom of the packer, then smoothly opening the sealing slide valve by reinserting the pipe column, and communicating the sealing slide valve with a cement squeezing channel of the guide valve body to carry out cement squeezing operation again;

and (3) a pipe column removing process: after the cement extrusion is finished, the pipe column is directly lifted, the separation between the pipe column and the packer can be completed, and meanwhile, the tail sealing slide valve is closed, so that the liquid isolation of the unset cement paste at the tail of the packer is ensured.