CN211900560U

CN211900560U - Multiple-time seat-seal preset type throttler

Info

Publication number: CN211900560U
Application number: CN201922064182.XU
Authority: CN
Inventors: 赵锋叶; 殷学鹏; 常少波
Original assignee: Baoji Ruilin Petroleum Electromechanical Equipment Co ltd
Current assignee: Baoji Ruilin Petroleum Electromechanical Equipment Co ltd
Priority date: 2019-11-26
Filing date: 2019-11-26
Publication date: 2020-11-10
Anticipated expiration: 2029-11-26

Abstract

The invention discloses a multi-time seat-sealing preset type choke which comprises a delivery tool and a choke core, wherein a preset working barrel type underground choke mainly comprises a working barrel and a core. When a new downhole completion production string is used, a mandrel is installed at the design location. The simultaneous connection and releasing are completed by adopting the matching of the releasing shear pin and the central tube with the elastic claw, so that the upper and lower double-connection limit is formed, and the effective matching of the delivery tool and the throttling core is improved; the seat seal piston enables the seat seal piston to move only in a single way through a one-way displacement structure, the seat seal position is locked and seat sealed on the rubber cylinder mandrel, and in addition, the rubber cylinder is prevented from being excessively extruded through the cooperation of the step six and the step seven, so that the seat seal is effectively performed. When the air tap needs to be replaced, a matched fishing tool is put in by utilizing steel wire operation, and the core can be fished out by grabbing the lock block shaft and lifting. The choke seat, the releasing, the deblocking and the fishing are reliable, and the utility of the choke is greatly improved.

Description

Multiple-time seat-seal preset type throttler

Technical Field

The invention relates to the technical field of natural gas exploitation, in particular to a multiple-seat-seal preset type choke.

Background

In natural gas production, for depressurization, throttling and production limitation, a downhole choke is usually installed in a shaft and fixed in a setting manner underground for downhole throttling. The conventional ground throttling process utilizes a ground heating and heat-insulating device to heat natural gas before throttling, so that the temperature of airflow is increased, and hydrate blockage is avoided. The underground throttling process technology realizes the throttling and pressure reduction of a shaft by using underground special equipment, and the temperature of the airflow at the well mouth after throttling is basically recovered to the temperature before throttling by using the ground temperature for heating, so that the technical problems of the shaft and the ground in the production process of a gas well are solved, and the underground throttling has the following advantages compared with the ground throttling: the operating pressure of the ground pipeline is greatly reduced; effectively preventing the formation of hydrate and improving the well opening efficiency; a wellhead heating furnace is not needed for well opening and production of the gas well; the method is favorable for preventing stratum excitation and interwell interference and automatically deploying the ground pressure system in a larger range.

The preset working barrel type downhole choke is mainly composed of a delivery tool and a throttling core, when a new downhole well completion production string is used, the working barrel is installed at a designed position, and the throttling core is delivered into a corresponding position in the working barrel through the delivery tool. The existing throttler has the advantages that the matching mode of a delivery tool and a throttling core is simple, the throttling core is generally connected and limited through a shear pin, and when the throttling core is put into a well by the delivery tool, the throttling core is easy to collide with the well wall, so that the shear pin is sheared and loses effectiveness; in addition, after the existing choke seat is sealed, the locking effect is low, and the choke seat can be easily unsealed automatically, so that the choke seat falls into a well, and the production cost is increased.

Disclosure of Invention

Aiming at the existing problems, the invention aims to provide a multi-time seat-sealing preset type throttler which comprises a delivery tool and a throttling core, wherein a releasing shear pin and a central pipe are matched with an elastic claw to complete simultaneous connection and releasing, so that upper and lower double-connection limit is formed, and the effective matching of the delivery tool and the throttling core is improved; the seat seal piston enables the seat seal piston to move only in a single way through a one-way displacement structure, the seat seal position is locked and seat sealed on the rubber cylinder mandrel, and in addition, the rubber cylinder is prevented from being excessively extruded through the cooperation of the step six and the step seven, so that the seat seal is effectively performed.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows: the utility model provides a multiple-time seat seals preset throttle, includes delivery instrument and throttle core, the cooperation of throttle core is connected in delivery instrument below, its characterized in that: the delivery tool comprises a mandrel, an upper connector and a clamping seat are sequentially sleeved on the top of the mandrel, a shearing connector and a pull rod are sequentially connected to the bottom of the mandrel, a first step is arranged on the top of the mandrel, the upper connector and the clamping seat are sleeved on the first step, the first step limits the clamping seat to move downwards in one direction, a first groove is formed in the first step, an elastic snap ring matched with the first groove is arranged between the upper connector and the clamping seat, a clamping block is movably arranged in the clamping seat, the height of the clamping block is smaller than that of the first step, the upper connector and the mandrel are connected through a delivery shear pin, and a central pipe is movably sleeved on the pull;

the throttling core comprises a base sealing head, a second step is arranged at the bottom of the base sealing head, a locking cap and a slip seat are sequentially sleeved on the second step, a retainer ring is arranged between the locking cap and the second step, the locking cap and the slip seat limit the second step to move upwards in one direction through the retainer ring, slips are embedded on the slip seat and are sealed through the second step, an unsealing sleeve, an unsealing connector, a connecting sleeve, a top shoe, a rubber cylinder, a bottom shoe and an overflowing connector are sequentially connected to the bottom of the slip seat, a third step and a fourth step are sequentially arranged on the unsealing sleeve and the unsealing connector, the unsealing sleeve and the unsealing connector are connected through an unsealing shear pin, a rubber cylinder core shaft and a sealing piston are sequentially arranged in the rubber cylinder, the top end of the rubber cylinder core shaft abuts against the connecting sleeve, a fifth step is arranged at the bottom end of the rubber cylinder core shaft, the top end of the bottom shoe is clamped between the rubber cylinder and the, the shoulder is clamped between the sole shoe and the overflowing connector, a matched one-way displacement structure is arranged between the rubber cylinder mandrel and the seat seal piston, the upward displacement of the seat seal piston is locked through the one-way displacement structure, and the inner wall of the bottom of the seat seal piston is sequentially provided with an air nozzle and a pressing cap;

the inner wall of the seat sealing head is provided with a second groove matched with the clamping block, the seat sealing head is connected with the delivery tool through the clamping block, and the shearing joint is connected with the slip seat through the releasing shearing pin.

Preferably, the bottom of the central tube is provided with an elastic bulge, an elastic claw is arranged between the top end of the rubber cylinder mandrel and the connecting sleeve, and the inner wall of the elastic claw is provided with a fourth groove matched with the elastic bulge.

Preferably, a bottom of the step is provided with a slope structure.

Preferably, the bottom of the step II is provided with a first inclined surface structure, and the first inclined surface structure abuts against the slip.

Preferably, the step II is provided with a groove III, the groove III is internally provided with a righting ring, and the outer wall of the righting ring is attached to the inner wall of the slip seat.

Preferably, the rubber cylinder mandrel and the seat seal piston are sequentially provided with a step six and a step seven which are matched with each other.

Preferably, the one-way displacement structure comprises an inner lock ring buckle and an outer lock ring buckle which are sequentially arranged on the rubber cylinder mandrel and the seat seal piston.

Preferably, an air nozzle check ring is arranged between the air nozzle and the seat seal piston.

The invention has the beneficial effects that: (1) the shear joint and the slip seat are connected through a releasing shear pin, the pull rod is connected with the central pipe, the central pipe is connected with the elastic claw, when the delivery throttling core is placed down and released, the releasing shear pin and the central pipe are matched with the elastic claw to complete simultaneous connection and release, upper and lower dual connection limit is formed, and effective matching of a delivery tool and the throttling core is improved. The pulling rod can move only after the releasing shear pin is sheared by the lifting delivery tool, and the central pipe is not limited after the pulling rod moves, so that the central pipe is separated from the elastic claw and is separated from the throttling core. The structure is formed by adopting double fixing and releasing, and the releasing and delivering of the tool are safely and effectively ensured. (2) The pull rod supports the central tube, the central tube is limited in the elastic claw, and the elastic claw is limited in the connecting sleeve. The center tube and the elastic claw are both locked elastically, so that when the tool is sealed and delivered, effective connection is guaranteed, and the delivery and deblocking are safe and effective. (3) The transition joint is connected with the bottom shoe, the bottom shoe is clamped between the rubber cylinder and the rubber cylinder mandrel, the bottom shoe limits the rubber cylinder mandrel through the overflow joint, and the seat seal piston can move relative to the rubber cylinder mandrel through the one-way locking effect of the inner lock ring buckle and the outer lock ring buckle, so that the rubber cylinder seat seal is locked. The structure not only enables the rubber cylinder core shaft to complete seat seal locking, but also can utilize underground pressure to play a role in throttling and pressure reduction of the seat seal, and improves the effectiveness of the seat seal. (4) The step three and the step four are matched with each other, so that the reliability of the seat seal is guaranteed, and thorough and effective unsealing is also guaranteed. (5) The inclined plane structure improves the rapid separation of the clamping block and the clamping seat and the separation of the seat sealing head and the upper part of the delivery tool; the elastic snap ring is limited fast by the aid of self elasticity and the first groove 242, smooth separation of the clamping block and the clamping seat is guaranteed, smooth separation of the seat sealing head and the delivery tool is guaranteed, when the delivery tool is lifted up to release the hands, the elastic snap ring is clamped in the first groove and integrally forms with the mandrel, meanwhile, the clamping block is also clamped in the lower part of the step, the mandrel is driven to move upwards, and the delivery tool is released. (6) The seat seal piston only can move singly through the one-way displacement structure, the seat seal position is locked and seat sealed on the rubber cylinder mandrel, and when the underground pressure is reduced or is 0, the seat seal piston is also locked on the inner lock ring buckle and the outer lock ring buckle of the one-way displacement structure, so that the rubber cylinder is always in a seat seal locking state. (7) The arranged centering ring can improve the assembly verticality of the slip seat and the slip, and improve the sealing precision of the slip seat;

drawings

Fig. 1 is an overall structural view of the preset throttle.

Fig. 2 is an overall structural view of the delivery tool of the present invention.

FIG. 3 is an enlarged view of the delivery tool A of the present invention.

FIG. 4 is an enlarged view of the delivery tool B of the present invention.

Fig. 5 is an overall structural view of the throttle core of the present invention.

Fig. 6 is an enlarged view of the throttle core C of the present invention.

FIG. 7 is an enlarged view of the throttle core D of the present invention.

Fig. 8 is an enlarged view of the throttle core E of the present invention.

Detailed Description

In order to make those skilled in the art better understand the technical solution of the present invention, the following further describes the technical solution of the present invention with reference to the drawings and the embodiments.

Referring to fig. 1-8, the multiple-seating preset throttle comprises a delivery tool and a throttle core, wherein the throttle core is connected below the delivery tool in a matching manner, the delivery tool comprises a mandrel 24, an upper joint 23 and a clamping seat 27 are sequentially sleeved on the top of the mandrel 24, the bottom of the mandrel 24 is sequentially connected with a shearing joint 29 and a pull rod 31, the shearing joint 29 is connected with the mandrel 24 and the pull rod 31 through a flat-end set screw, a step I241 is arranged on the top of the mandrel 24, the upper joint 23 and the clamping seat 27 are sleeved on the step I241, the upper joint 23 and the clamping seat 27 are preferably connected through the flat-end set screw, the step I241 unidirectionally limits the clamping seat 27 to move downwards, a groove I242 is arranged on the step I241, an elastic snap ring 26 matched with the groove I is arranged between the upper joint 23 and the clamping seat 27, and a clamping block 28 is movably arranged in the clamping seat 27, the height of the fixture block 28 is smaller than that of the step I241, so that the fixture block 28 is conveniently separated from the fixture seat 27, the upper connector 23 is connected with the mandrel 24 through the delivery shear pin 25, the initial positions of the upper connector 23 and the mandrel 24 are limited through the delivery shear pin 25, the pull rod 31 is movably sleeved with the central pipe 30, the bottom end of the pull rod 31 is provided with the step, and the central pipe 30 moves up and down through the step;

the clamping seat 27 acts on the upper joint 23 through the limitation of the first step 241 and through external force, the clamping seat 27 drives the upper joint 23 and the elastic clamping ring 26 to move downwards in one direction relative to the mandrel 24, the delivery shear pin 25 is sheared, the clamping block 28 falls below the first step 241 and is separated from the seat sealing head 23, the elastic clamping ring 26 is clamped in the first groove 242 through the elastic force of the elastic clamping ring 26, the clamping block 28 is ensured to be separated from the clamping seat 27 smoothly, and the seat sealing head 1 is ensured to be separated from a delivery tool smoothly; when the delivery tool is lifted up for releasing, the elastic snap ring 26 is clamped in the first groove 242 and is integrated with the mandrel 24, and the clamping block 28 is also clamped below the first step 241 and drives the mandrel 24 to move upwards, so that the delivery tool is released.

The further improvement lies in that: the throttling core comprises a base seal head 1, a second step 101 is arranged at the bottom of the base seal head 1, a lock cap 2 and a slip seat 5 are sequentially sleeved on the second step 101, a retainer ring 3 is arranged between the lock cap 2 and the second step 101, the lock cap 2 and the slip seat 5 limit the second step 101 to move upwards in a single direction through the retainer ring 3, a slip 6 is embedded on the slip seat 5, the slip 6 is sealed through the second step 101, and during sealing, the second step 101 moves downwards to support the slip 6 for sealing;

the further improvement lies in that: the bottom of the slip seat 5 is sequentially connected with an unsealing sleeve 8, an unsealing joint 7, a connecting sleeve 9, a top shoe 11, a rubber cylinder 12, a bottom shoe 16 and a flow passing joint 20, the unsealing sleeve 8 and the unsealing joint 7 are sequentially provided with a step three 81 and a step four 71, the unsealing sleeve 8 and the unsealing joint 7 are connected through an unsealing shear pin 22, the step three 81 and the step four 71 mutually limit the displacement stroke of the unsealed shear pin 22 after being unsealed and broken, the rubber cylinder 12 is sequentially provided with a rubber cylinder mandrel 13 and a sealing piston 14, the top end of the rubber cylinder mandrel 13 is abutted against the connecting sleeve 9, the bottom end of the rubber cylinder mandrel is provided with a step five 131, the top end of the bottom shoe 16 is clamped between the rubber cylinder 12 and the step five 131, the sealing piston 14 is provided with a shoulder 141, the shoulder 141 is clamped between the bottom shoe 16 and the flow passing joint 20, a matched one-way displacement structure 15 is arranged between the rubber cylinder mandrel 13 and the, the upward displacement of the seat seal piston 14 is locked by a one-way displacement structure 15, and the inner wall of the bottom of the seat seal piston 14 is sequentially provided with an air tap 18 and a pressing cap 19;

during setting, the air pressure flowing in through the overflow connector 20 pushes the setting piston 14 to move upwards, meanwhile, the sole shoe 16 and the rubber cylinder 12 are sequentially pushed, the rubber cylinder 12 is supported to expand and set, and the setting piston 14 locks the setting position on the rubber cylinder mandrel 13 through the one-way displacement structure 15.

The further improvement lies in that: the inner wall of the socket head 1 is provided with a second groove 102 matched with the fixture block 28, the socket head 1 is connected with a delivery tool through the fixture block 28, the delivery tool can conveniently deliver the throttling core, and the shearing connector 29 is connected with the slip seat 5 through the releasing shear pin 21.

Further, in order to ensure effective connection between the delivery tool and the throttling core, the bottom of the central tube 30 is provided with an elastic bulge 301, an elastic claw 10 is arranged between the top end of the rubber cylinder core shaft 13 and the connecting sleeve 9, and the inner wall of the elastic claw 10 is provided with a groove IV 104 matched with the elastic bulge 301; elastic claw 10 and elastic bulge 301 all adopt elasticity locking, when the throttler seat seals with deliver, have guaranteed effectual connection promptly, have guaranteed again to deliver with the safe effective of deblocking.

Further, in order to smoothly complete the releasing operation of the delivery tool, the bottom of the first step 241 is provided with an inclined surface structure 243, after the throttling core is seated, the delivery shear pin 25 is sheared, the fixture block 28 falls below the first step 241, and the inclined surface structure 243 facilitates the fixture block 28 to smoothly separate from the clamping seat 27 and separate from the seat head 23, so that the subsequent releasing operation of the delivery tool is realized.

Further in order to rapidly support the slips 6 and carry out setting, the bottom of the second step 101 is provided with a first inclined surface structure 105, the first inclined surface structure 105 abuts against the slips 6, the second step 101 moves downwards, the slips 6 are sleeved on the second step 101 through the first inclined surface structure 105, the slips 6 expand after being supported, and setting is formed in the sleeve.

Further in order to improve the setting precision of the throttling core, a third groove 103 is formed in the second step 101, a centering ring 4 is arranged in the third groove 103, the outer wall of the centering ring 4 is attached to the inner wall of the slip seat 5, the centering ring 4 can improve the assembling verticality of the slip seat 5 and the slip 6, and the setting precision of the slip 6 is improved.

Further, in order to protect the smooth setting of the rubber cylinder 12, a step six 132 and a step seven 142 which are matched with each other are sequentially arranged on the rubber cylinder mandrel 13 and the setting piston 14, during setting, the air pressure flowing in through the overflow connector 20 pushes the setting piston 14 to move upwards, meanwhile, the shoe sole 16 and the rubber cylinder 12 are sequentially pushed, the rubber cylinder 12 is supported to expand and set, the setting piston 14 locks the setting position on the rubber cylinder mandrel 13 through the one-way displacement structure 15, in order to prevent the excessive air pressure or the failure of the one-way displacement structure 15, the displacement stroke of the setting piston 14 is further limited through the matching of the step six 132 and the step seven 142, the rubber cylinder 14 is prevented from being excessively extruded, the rubber cylinder 12 is prevented from being damaged, and the throttling effect of the whole throttling device is influenced.

Further, in order to better lock the seat seal of the rubber cylinder 12, the one-way displacement structure 15 includes an inner lock ring buckle and an outer lock ring buckle which are sequentially arranged on the rubber cylinder mandrel 13 and the seat seal piston 14, and the positions of the shoe sole 16 and the rubber cylinder 12 which are pushed by the seat seal piston 14 are locked in a one-way locking mode by the inner lock ring buckle and the outer lock ring buckle.

In order to further improve the sealing performance of the throttling, a gas nozzle retaining ring 17 is arranged between the gas nozzle 18 and the seat sealing piston 14.

The principle of the invention is as follows:

one, seat and releasing

When the tool is lowered into the well, the upper part of the upper joint 23 is connected with a steel wire rope, the tool is assembled with the throttling core, then the tool is sent to the position of a preset working barrel in the well by the steel wire rope, the weight of a pipe column is lowered, the lower part of the pipe column is shocked for several times, the delivery shearing pin 3 is sheared, at the moment, the clamping seat 27, the clamping block 28 and the setting head 1 which are connected with the upper joint 23 move downwards together, when the setting head 1 moves downwards to a certain position, the slip 6 moves upwards along the inclined plane structure I105 on the setting head 1, the slip 6 is propped open and fixed on a step in the working barrel to form setting limit, the elastic clamping ring 26 is clamped in the groove I242 by the self elasticity to form setting locking, the clamping block 28 also moves to the lower part of the step I241 of the core shaft 24 together with the clamping seat 27, the clamping block 28 slides along the inclined plane structure 243 and is separated from the clamping seat, separating the upper end of the seat seal head 1 from the delivery tool; and continuously lifting the delivery tool to cut off the releasing shear pin 21 at the lower part and move the pull rod 31 upwards together to separate the central pipe 30 from the elastic claw 10 and release the limit, and at the moment, the delivery tool is completely separated from the throttling core to finish releasing.

When the underground throttling gas pressure reaches a set value (preferably 3-5MPa), the pressure enters the throttling core through a gap on the transition joint 20, the seating piston 14 is pushed to move upwards, the shoulder 141 pushes the sole shoes 16 to move upwards to extrude the rubber cylinder 12, the rubber cylinder 12 is supported to expand the seating, the seating piston 14 enables the seating piston 14 to move only in a single way through the one-way displacement structure 15, the seating position is locked and seated on the rubber cylinder mandrel 13, and when the underground pressure is reduced or is 0, the seating piston 14 is also locked on the inner locking ring buckle and the outer locking ring buckle of the one-way displacement structure 15, so that the rubber cylinder 12 is always in a seating and locking state.

Second, unsealing and fishing

The special fishing tool is adopted to be lowered to the position of the seat sealing head 1, when the fishing tool is lifted, a clamping jaw of the fishing tool is clamped on a step in the seat sealing head 1, the seat sealing head 1 is lifted to move upwards, the clamping shoe 6 falls on the step below the seat sealing head 1 to reset and is separated from the working barrel, meanwhile, the seat sealing head 1 drives the unsealing sleeve 8, the unsealing sleeve 8 and the unsealing joint 7 generate relative displacement, the unsealing shear pin 22 is sheared, the unsealing sleeve 8 continues to move upwards, the unsealing joint 7, the connecting sleeve 9 and the top shoe 11 are sequentially driven to move upwards, the rubber barrel 12 resets, unsealing is completed, and lifting and fishing are carried out.

The foregoing shows and describes the general principles, essential features, and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims

1. The utility model provides a multiple-time seat seals preset throttle, includes delivery instrument and throttle core, the cooperation of throttle core is connected in delivery instrument below, its characterized in that: the delivery tool comprises a mandrel (24), the top of the mandrel (24) is sequentially sleeved with an upper joint (23) and a clamping seat (27), the bottom of the core shaft is sequentially connected with a shearing joint (29) and a pull rod (31), the top of the core shaft (24) is provided with a first step (241), the upper joint (23) and the clamping seat (27) are sleeved on the first step (241), the first step (241) limits the downward movement of the clamping seat (27) in one way, a first groove (242) is arranged on the first step (241), an elastic snap ring (26) matched with the first groove (242) is arranged between the upper joint (23) and the clamping seat (27), a clamping block (28) is movably arranged in the clamping seat (27), the height of the clamping block (28) is smaller than that of the first step (241), the upper joint (23) is connected with the mandrel (24) through a delivery shear pin (25), and a central pipe (30) is movably sleeved on the pull rod (31);

the throttling core comprises a base seal head (1), a step II (101) is arranged at the bottom of the base seal head (1), a lock cap (2) and a slip seat (5) are sequentially sleeved on the step II (101), a check ring (3) is arranged between the lock cap (2) and the step II (101), the lock cap (2) and the slip seat (5) limit the step II (101) to move upwards in a single direction through the check ring (3), a slip (6) is embedded on the slip seat (5), the slip (6) is sealed through the step II (101), a sealing-off sleeve (8), a sealing-off joint (7), a connecting sleeve (9), a top shoe (11), a rubber cylinder (12), a bottom shoe (16) and an overflowing joint (20) are sequentially connected at the bottom of the slip seat (5), a step III (81) and a step IV (71) are sequentially arranged on the sealing-off sleeve (8) and the overflowing joint (7), the unsealing sleeve (8) and the unsealing connector (7) are connected through an unsealing shear pin (22), a rubber sleeve mandrel (13) and a sealing piston (14) are sequentially arranged in the rubber sleeve (12), the top end of the rubber sleeve mandrel (13) abuts against the connecting sleeve (9), the bottom end of the rubber sleeve mandrel (13) is provided with a step five (131), the top end of the bottom shoe (16) is clamped between the rubber sleeve (12) and the step five (131), the sealing piston (14) is provided with a shoulder (141), the shoulder (141) is clamped between the bottom shoe (16) and the overflowing connector (20), a matched one-way displacement structure (15) is arranged between the rubber sleeve mandrel (13) and the sealing piston (14), the sealing piston (14) is upwards displaced and locked through the one-way displacement structure (15), and the inner wall of the bottom of the sealing piston (14) is sequentially provided with an air nozzle (18) and a pressing cap (19);

the inner wall of the socket end enclosure (1) is provided with a second groove (102) matched with the clamping block (28), the socket end enclosure (1) is connected with a delivery tool through the clamping block (28), and the shearing joint (29) is connected with the slip seat (5) through the releasing shearing pin (21).

2. The multiple-seat preset choke of claim 1, wherein: the rubber tube is characterized in that an elastic bulge (301) is arranged at the bottom of the central tube (30), an elastic claw (10) is arranged between the top end of the rubber tube mandrel (13) and the connecting sleeve (9), and a groove IV (104) matched with the elastic bulge (301) is arranged on the inner wall of the elastic claw (10).

3. The multiple-seat preset choke of claim 2, wherein: the bottom of the first step (241) is provided with a slope structure (243).

4. A multiple-seat preset choke according to claim 3, wherein: the bottom of the second step (101) is provided with a first inclined surface structure (105), and the first inclined surface structure (105) is abutted to the slip (6).

5. The multiple-seat preset choke of claim 4, wherein: a third groove (103) is formed in the second step (101), a righting ring (4) is arranged in the third groove (103), and the outer wall of the righting ring (4) is attached to the inner wall of the slip seat (5).

6. The multiple-seat preset choke of claim 5, wherein: and a step six (132) and a step seven (142) which are matched with each other are sequentially arranged on the rubber cylinder mandrel (13) and the seat seal piston (14).

7. The multiple-seat preset choke of claim 6, wherein: the one-way displacement structure (15) comprises an inner lock ring buckle and an outer lock ring buckle which are sequentially arranged on the rubber cylinder mandrel (13) and the seat seal piston (14).

8. The multiple-seat preset choke of claim 7, wherein: an air nozzle retainer ring (17) is arranged between the air nozzle (18) and the seat seal piston (14).