An electromagnetic induction launch type drop-out short section for a self-sealing plug

Abstract

The present invention relates to the technical field of supporting tools for oilfield development, and in particular to an electromagnetic induction-launched release short section for a self-sealing plug. The present invention comprises a falling body assembly, an acceleration mechanism, a tubing buckle short section, a projectile seat and a coupling; the falling body assembly comprises a falling body armature and a projectile arranged below the falling body armature. The acceleration mechanism is configured to generate an instantaneous magnetic field to accelerate the falling body assembly passing through the acceleration mechanism; the projectile impacts the projectile seat after acceleration, thereby separating the tubing buckle short section and the coupling. The electromagnetic induction-launched release short section for a self-sealing plug provided by the present invention generates an induced current in the falling body armature through the instantaneous magnetic field generated by the acceleration mechanism. The induced current magnetic field generated by the falling body armature is opposite to the direction of the magnetic flux lines of the instantaneous magnetic field. The magnetic poles of the falling body armature on the side close to the acceleration mechanism are opposite, so the instantaneous magnetic field generated by the acceleration mechanism pushes the falling body armature and then the falling body armature pushes the projectile, so that the projectile has sufficient kinetic energy to impact the projectile seat, thereby achieving rapid release.

Description

Technical Field

[0001] The invention relates to the technical field of supporting tools for oilfield development, in particular to an electromagnetic induction launching type hand-release short section for a self-sealing plugger. Background Art

[0002] Usually, when a Christmas tree or main gate at the wellhead leaks, it is necessary to put a continuous tubing under pressure to insert a casing plug, seal the casing plug, and after the sealing is qualified, the construction process of replacing the Christmas tree or main gate at the wellhead can be carried out. Since the continuous tubing needs to carry out more important construction processes such as the early oil test of the shale oil platform well, it is necessary to study the self-sealing plug that is automatically released from the wellhead to achieve casing sealing. Usually, a sliding sleeve type hydraulic release short section can be considered to achieve the release between the self-sealing plug, but in the event of an emergency such as a leak at the wellhead, it is necessary to contact the cement truck on site and use the cement truck to pressurize to achieve hydraulic release, which cannot solve the wellhead leakage problem in time. Therefore, a quick-response and easy-to-operate release short section is needed to win precious time for replacing the Christmas tree or main gate at the wellhead, and at the same time, it can solve the wellhead leakage problem in time and avoid the occurrence of well control safety problems. Summary of the invention

[0003] The purpose of the present invention is to provide an electromagnetic induction launch type release short section for a self-sealing plug, so that the self-sealing plug can be quickly released when a leak occurs in the wellhead Christmas tree or the main gate, thereby promptly solving the wellhead leakage problem and avoiding the occurrence of well control safety problems.

[0004] In order to solve the above technical problems, the technical solution provided by the present invention is:

[0005] An electromagnetic induction launch type hand-release short section for a self-sealing plugger comprises a falling body assembly, an acceleration mechanism, a tubing buckle short section, a projectile seat and a coupling; the tubing buckle short section is fixedly connected to the projectile seat through a short pin, and the coupling is fixedly connected to the projectile seat through a long pin; the falling body assembly comprises a falling body armature and a projectile arranged below the falling body armature;

[0006] The acceleration mechanism is configured to generate an instantaneous magnetic field to accelerate the falling assembly passing through the acceleration mechanism; after the projectile is accelerated, it impacts the projectile seat, causing the projectile seat to shear the long pin and the short pin, thereby separating the oil pipe buckle short section and the coupling.

[0007] Furthermore, a conductive coil is provided on the falling body armature, and the axis of the conductive coil is coaxial with the axis of the falling body armature.

[0008] Furthermore, the falling body armature comprises an upper falling body section and a lower falling body section, the outer diameter of the upper falling body section is larger than the inner diameter of the lower falling body section, so that the falling body armature forms a first step at the connection between the upper falling body section and the lower falling body section.

[0009] Furthermore, the acceleration mechanism includes a driving coil, and the falling armature passes through the driving coil.

[0010] Furthermore, the acceleration mechanism also includes a capacitor group, which is connected in series with the driving coil.

[0011] Furthermore, the acceleration mechanism also includes a trigger switch, which is connected in series with the drive coil and the capacitor group.

[0012] Furthermore, the acceleration mechanism also includes a photoelectric switch, which is arranged below the driving coil and is excited when the falling armature leaves the driving coil to control the trigger switch.

[0013] Furthermore, the oil pipe buckle short section is arranged below the acceleration mechanism, and the inner circle of the oil pipe buckle short section is provided with a second step; after the falling armature enters the oil pipe buckle short section, the first step of the falling armature collides with the second step.

[0014] Furthermore, the projectile seat includes an upper section and a lower section. The upper section of the projectile seat is inserted into the lower end of the oil pipe variable buckle short section. The connection between the upper section of the projectile seat and the lower section of the projectile seat is provided with a projectile bayonet, and the diameter of the projectile bayonet is smaller than the diameter of the projectile.

[0015] Furthermore, the projectile seat is arranged in the coupling and connected to the coupling; the lower section of the inner circle of the coupling is provided with a third step, and the inner diameter of the third step is smaller than the outer diameter of the lower section of the projectile seat.

[0016] Based on the above technical solutions, the technical effects that can be achieved by the present invention are:

[0017] The electromagnetic induction launch type hand-release short section for the self-sealing plug provided by the present invention comprises a falling body assembly, an acceleration mechanism, a tubing buckle short section, a projectile seat and a coupling; the tubing buckle short section is fixedly connected to the projectile seat through a short pin, and the coupling is fixedly connected to the projectile seat through a long pin; the falling body assembly comprises a falling body armature and a projectile arranged below the falling body armature. The acceleration mechanism is configured to generate an instantaneous magnetic field to accelerate the falling body assembly passing through the acceleration mechanism; after the projectile is accelerated, it impacts the projectile seat, so that the projectile seat cuts the long pin and the short pin, thereby separating the tubing buckle short section and the coupling.

[0018] Since the electromagnetic induction launch type release short section for the self-sealing plug provided by the present invention generates an induced current in the falling armature through the instantaneous magnetic field generated by the acceleration mechanism, the induced current magnetic field generated by the falling armature is opposite to the direction of the magnetic flux lines of the instantaneous magnetic field, and the magnetic poles of the falling armature on the side close to the acceleration mechanism are opposite, so the instantaneous magnetic field generated by the acceleration mechanism pushes the falling armature and then the falling armature pushes the projectile, so that the projectile has sufficient kinetic energy to impact the projectile seat, so that the projectile seat cuts off the long pins and the short pins, thereby separating the oil pipe buckle short section from the coupling, and realizing rapid release. Compared with the conventional hydraulic pushing method, this method does not need to contact the cement truck for pressure, and the falling assembly can be thrown in from the wellhead in an emergency, accelerated by the acceleration mechanism, and the self-sealing plug can be quickly released, thereby promptly solving the wellhead leakage problem and avoiding the occurrence of well control safety problems. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 A schematic diagram of an electromagnetic induction launch type release short section for a self-sealing plug provided in an embodiment of the present invention;

[0021] Figure 2 A cross-sectional view of a falling armature 100 of an electromagnetic induction launching type drop-out short section for a self-sealing plugger provided in an embodiment of the present invention;

[0022] Figure 3 A cross-sectional view of a projectile seat 900 of an electromagnetic induction launch type release short section for a self-sealing plugger provided in an embodiment of the present invention;

[0023] Figure 4 A cross-sectional view of an oil pipe buckle-changing nipple 800 of an electromagnetic induction launch type drop nipple for a self-sealing plug provided in an embodiment of the present invention;

[0024] Icons: 100-falling body armature; 200-projectile; 300-driving coil; 400-capacitor bank; 500-armature track; 600-trigger switch; 700-photoelectric switch; 800-oil pipe buckle short section; 900-projectile seat; 1000-hoop; 1100-sealing ring; 1200-short pin; 1300-long pin; 110-conductive coil; 120-falling body upper section; 130-falling body lower section; 140-first step; 810-second step; 820-fourth step; 830-buckling short section upper section; 840-buckling short section lower section; 910-projectile bayonet; 920-sealing groove; 930-projectile seat upper section; 940-projectile seat lower section; 950-limiting step; 1010-third step. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0026] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0028] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the product of the invention is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0029] In addition, the terms "horizontal", "vertical", "overhanging" and the like do not mean that the components are required to be absolutely horizontal or overhanging, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0030] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0031] Some embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0032] Usually, when a Christmas tree or main gate at the wellhead leaks, it is necessary to put a continuous tubing under pressure to insert a casing plug, seal the casing plug, and after the sealing is qualified, the construction process of replacing the Christmas tree or main gate at the wellhead can be carried out. Since the continuous tubing needs to carry out more important construction processes such as the early oil test of shale oil platform wells, it is necessary to study the self-sealing plug that is automatically released from the wellhead to achieve casing sealing. Usually, a sliding sleeve type hydraulic release short section is used to achieve the release between the self-sealing plug, but in the event of an emergency such as a leak at the wellhead, it is necessary to contact a cement truck on site and use the cement truck to pressurize to achieve hydraulic release, which cannot solve the wellhead leakage problem in time.

[0033] In view of this, the present invention provides an electromagnetic induction launch type hand-release short section for a self-sealing plug, comprising a falling assembly, an acceleration mechanism, a tubing buckle short section 800, a projectile seat 900 and a coupling 1000; the tubing buckle short section 800 is fixedly connected to the projectile seat 900 through a short pin 1200, and the coupling 1000 is fixedly connected to the projectile seat 900 through a long pin 1300; the falling assembly comprises a falling armature and a projectile 200 arranged below the falling armature. The acceleration mechanism is configured to generate an instantaneous magnetic field to accelerate the falling assembly passing through the acceleration mechanism; after the projectile 200 is accelerated, it impacts the projectile seat 900, so that the projectile seat 900 cuts off the long pin 1300 and the short pin 1200, thereby separating the tubing buckle short section 800 and the coupling 1000.

[0034] Since the electromagnetic induction launch type release short section for the self-sealing plug provided by the present invention generates an induced current in the falling armature through the instantaneous magnetic field generated by the acceleration mechanism, the induced current magnetic field generated by the falling armature is opposite to the direction of the magnetic flux lines of the instantaneous magnetic field, and the magnetic poles of the falling armature on the side close to the acceleration mechanism are opposite, so the instantaneous magnetic field generated by the acceleration mechanism pushes the falling armature and then the falling armature pushes the projectile 200, so that the projectile 200 has sufficient kinetic energy to impact the projectile seat 900, so that the projectile seat 900 cuts off the long pin 1300 and the short pin 1200, so that the oil pipe buckle short section 800 is separated from the coupling 1000, and a quick release is achieved. Compared with the conventional hydraulic pushing method, this method does not need to contact the cement truck for pressure, and the falling assembly can be thrown in from the wellhead in an emergency, accelerated by the acceleration mechanism, and the self-sealing plug can be quickly released, thereby promptly solving the wellhead leakage problem and avoiding the occurrence of well control safety problems.

[0035] The following is combined with Figure 1 , 2 , 3, 4 describe in detail the structure and shape of the electromagnetic induction launch type release short section for the self-sealing plug provided in this embodiment:

[0036] like Figure 2 As shown, the falling body armature 100 includes a conductive coil 110, a falling body upper section 120 and a falling body lower section 130. The axis of the conductive coil 110 is coaxial with the axis of the falling body armature 100. The outer diameter of the falling body upper section 120 is greater than the outer diameter of the falling body lower section 130, so that the outer circle of the falling body armature 100 forms a first step 140 at the connection between the falling body upper section 120 and the falling body lower section 130.

[0037] like Figure 1 As shown, the projectile 200 is arranged at the end of the falling body lower section 130 away from the falling body upper section 120, and the end away from the falling body armature 100 is spherical. The upper end of the projectile 200 is embedded in the falling body lower section 130 of the falling body armature 100 and has an interference fit with the falling body lower section 130.

[0038] The acceleration mechanism in this embodiment includes a driving coil 300, such as Figure 1 As shown, the axis of the driving coil 300 is parallel to the axis of the falling body assembly, the diameter of the falling body assembly is smaller than the inner diameter of the driving coil 300 , and the falling body assembly passes through the driving coil 300 .

[0039] Furthermore, the acceleration mechanism also includes a capacitor group 400, which is connected in series with the drive coil 300 to provide an instantaneous pulse current to the drive coil 300, so that the drive coil 300 generates an instantaneous magnetic field.

[0040] Furthermore, the acceleration mechanism also includes a trigger switch 600, which is connected in series with the drive coil 300 and the capacitor group 400, and the trigger switch 600 is used to control the on-off of the circuit.

[0041] Furthermore, the acceleration mechanism also includes a photoelectric switch 700, which is arranged below the drive coil 300. When the falling component passes through the photoelectric switch 700, the photoelectric switch 700 is first blocked and no action occurs. When the falling component leaves the photoelectric switch 700, the photoelectric switch 700 controls the trigger switch 600. At this time, the circuit is connected, and the capacitor group 400 supplies electricity to the drive coil 300, so that the drive coil 300 generates an instantaneous magnetic field.

[0042] The electromagnetic induction launch type release short section for the self-sealing plug provided in this embodiment also includes an armature track 500, such as Figure 1 As shown, the driving coil 300 is disposed on the armature track 500 and is coaxial with the armature track 500 .

[0043] Furthermore, a plurality of acceleration mechanisms are arranged along the axial direction of the armature track 500 , and the plurality of acceleration mechanisms can accelerate the falling body assembly multiple times, so that the falling body assembly obtains sufficient kinetic energy.

[0044] Further, such as Figure 1 , 4 As shown, the oil pipe variable buckle short section 800 includes a variable buckle short section upper section 830 and a variable buckle short section lower section 840, the upper section of the oil pipe variable buckle short section 800 is connected to the lower end of the armature track 500; the inner diameter of the variable buckle short section 830 is larger than the inner diameter of the variable buckle short section 840, and the variable buckle short section upper section 830 and the variable buckle short section lower section 840 form a second step 810 on the inner side of the oil pipe variable buckle short section 800. The second step 810 cooperates with the first step 140 to limit the position of the falling armature 100.

[0045] Further, such as Figure 1 , 3 As shown, the projectile seat 900 includes a projectile seat upper section 930 and a projectile seat lower section 940, and the projectile seat upper section 930 is inserted into the lower section 840 of the variable buckle short section. The outer diameter of the projectile seat upper section 930 is smaller than the outer diameter of the projectile seat lower section 940, and the projectile seat upper section 930 and the projectile seat lower section 940 form a limiting step 950 on the outer side of the projectile seat 900, and the limiting step 950 contacts the lower end of the oil pipe variable buckle short section 800, which is used to limit the distance that the projectile seat 900 is inserted into the lower section 840 of the variable buckle short section.

[0046] Furthermore, a projectile bayonet 910 is provided at the inner circle of the connection between the projectile seat upper section 930 and the projectile seat lower section 940. The diameter of the projectile bayonet 910 is smaller than the diameter of the projectile 200 and is used to prevent the projectile 200 from continuing to move after the projectile 200 hits.

[0047] Furthermore, the short pin 1200 radially passes through the side wall of the lower section 840 of the variable buckle short section and then is inserted into the upper section 930 of the projectile seat, so that the oil pipe variable buckle short section 800 and the projectile seat 900 are fixedly connected.

[0048] Further, the lower section 840 of the variable buckle short section and the projectile seat 900 are inserted into the coupling 1000. The outer diameter of the upper section 830 of the variable buckle short section is larger than the outer diameter of the lower section 840 of the variable buckle short section, and the upper section 830 of the variable buckle short section and the lower section 840 of the variable buckle short section form a fourth step 820 at the connection, and the upper end surface of the coupling 1000 contacts the fourth step 820, which is used to limit the depth of the lower section 840 of the variable buckle short section and the projectile seat 900 inserted into the coupling 1000. The lower section of the inner side of the coupling 1000 is provided with a third step 1010, and the inner diameter of the third step 1010 is smaller than the outer diameter of the lower section 940 of the projectile seat, so that the projectile seat 900 does not fall out of the coupling 1000 after falling.

[0049] Furthermore, the long pin 1300 radially passes through the side wall of the coupling 1000 and is inserted into the lower section 940 of the shot seat, so that the coupling 1000 and the shot seat 900 are fixedly connected, thereby realizing the fixed connection of the oil pipe variable buckle short section 800, the shot seat 900 and the coupling 1000.

[0050] Furthermore, a sealing ring 1100 is provided between the outer circumference of the lower section 940 of the projectile seat and the inner side of the coupling 1000 to improve the sealing performance between the outer side of the projectile seat 900 and the inner side of the coupling 1000. A sealing groove 920 is provided on the outer circumference of the lower section 940 of the projectile seat for fixing the sealing ring 1100.

[0051] The assembly process of the electromagnetic induction launch type release short section for the self-sealing plug provided in this embodiment is as follows:

[0052] First, fix the drive coil 300 to the armature track 500, and connect it in series with the capacitor bank 400 and the trigger switch 600 to connect the circuit; then install the photoelectric switch 700 under the drive coil 300 and connect the control circuit; after connecting the control circuit, insert the upper section 930 of the projectile seat into the lower section 840 of the variable buckle short section, drive in the short pin 1200 to fix the oil pipe variable buckle short section 800 and the projectile seat 900; then, install the sealing ring 1100 is inserted into the lower section 840 of the variable buckle short section, and then the projectile seat 900 with the sealing ring 1100 and the oil pipe variable buckle short section 800 are inserted into the coupling 1000; after the projectile seat 900 with the sealing ring 1100 and the oil pipe variable buckle short section 800 are inserted into the coupling 1000, the long pin 1300 is driven in to fix the coupling 1000 and the projectile seat 900; finally, the upper end of the oil pipe variable buckle short section 800 is connected to the lower end of the armature track 500.

[0053] The working process of the electromagnetic induction launch type release short section for the self-sealing plug provided in this embodiment is as follows:

[0054] When leakage occurs, the control circuit is turned on, and the falling body assembly is dropped into the wellhead, so that the falling body assembly enters the armature track 500; when the falling body assembly passes through the driving coil 300 and blocks the photoelectric switch 700, the trigger switch 600 does not operate. When the falling body assembly continues to fall, after passing the photoelectric switch 700, it no longer blocks the photoelectric switch 700. At this time, the photoelectric switch 700 controls the trigger switch 600 to close the trigger switch 600, connect the circuit, and make the capacitor group 400 provide instantaneous current to the driving coil 300. The instantaneous current is the instantaneous magnetic field generated by the driving coil 300, so that the conductive coil 110 in the falling body armature 100 generates an induced current. According to Lenz's law, "the induced current has such a direction that the magnetic field of the induced current always hinders the change of the magnetic flux causing the induced current". It can be seen that because the magnetic flux of the instantaneous magnetic field causing the induced current increases instantaneously, the magnetic field of the induced current generated by the conductive coil 110 is opposite to the direction of the magnetic flux lines of the instantaneous magnetic field, that is, the magnetic poles of the driving coil 300 and the conductive coil 110 are opposite at this time. At this time, the conductive coil 110 is located below the driving coil 300, that is, the upper end of the conductive coil 110 is close to the lower end of the driving coil 300. Since the magnetic poles are in opposite directions, the magnetic poles of the conductive coil 110 and the driving coil 300 are the same at the point where they are close, so that the conductive coil 110 and the driving coil 300 repel each other. Since the driving coil 300 is fixed on the armature track 500, the driving coil 300 pushes the conductive coil 110 to accelerate the conductive coil 110, that is, the kinetic energy of the falling assembly is increased.

[0055] The falling assembly obtains sufficient kinetic energy through acceleration of multiple driving coils 300. After the falling assembly enters the tubing buckle short section 800, the first step 140 collides with the second step 810, and the speed of the falling armature 100 becomes zero. At this time, due to the effect of kinetic energy, the projectile 200 is separated from the falling armature 100, and the projectile 200 continues to move with higher kinetic energy. When the projectile 200 enters the projectile seat 900 and hits the projectile bayonet 910, the impact force of the projectile 200 causes the long pin 1300 and the short pin 1200 to be cut off at the same time, so that the projectile seat 900, the coupling 1000 and the tubing buckle short section 800 are separated from each other, and the projectile seat 900, the coupling 1000 and the tools connected below the coupling 1000 fall, realizing rapid release.

[0056] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An electromagnetic induction launch type release short section for a self-sealing plug, characterized in that: It includes a falling body assembly, an accelerating mechanism, an oil pipe buckle short section (800), a projectile seat (900) and a coupling (1000); The oil pipe buckle short section (800) is fixedly connected to the projectile seat (900) via a short pin (1200), and the coupling (1000) is fixedly connected to the projectile seat (900) via a long pin (1300); The falling body assembly comprises a falling body armature (100) and a projectile (200) arranged below the falling body armature (100); The acceleration mechanism is configured to generate a transient magnetic field to accelerate the falling assembly passing through the acceleration mechanism; The projectile (200) is accelerated and impacts the projectile seat (900), so that the projectile seat (900) shears the long pin (1300) and the short pin (1200), thereby separating the oil pipe buckle short section (800) and the coupling (1000); The falling body armature (100) is provided with a conductive coil (110), the acceleration mechanism comprises a driving coil (300), and the falling body armature (100) passes through the driving coil (300).

2. The electromagnetic induction launch type release short section for the self-sealing plug according to claim 1 is characterized in that: The axis of the conductive coil (110) is coaxial with the axis of the falling armature (100).

3. The electromagnetic induction launch type drop nipple for the self-sealing plug according to claim 2 is characterized in that The falling body armature (100) comprises a falling body upper section (120) and a falling body lower section (130), wherein the outer diameter of the falling body upper section (120) is greater than the inner diameter of the falling body lower section (130), so that the falling body armature (100) forms a first step (140) at the connection between the falling body upper section (120) and the falling body lower section (130).

4. The electromagnetic induction launch type release nipple for the self-sealing plug according to claim 3 is characterized in that: The acceleration mechanism further comprises a capacitor group (400), wherein the capacitor group (400) is connected in series with the driving coil (300).

5. The electromagnetic induction launch type release nipple for the self-sealing plug according to claim 4 is characterized in that: The acceleration mechanism further comprises a trigger switch (600), wherein the trigger switch (600) is connected in series with the drive coil (300) and the capacitor group (400).

6. The electromagnetic induction launch type release nipple for the self-sealing plug according to claim 5 is characterized in that: The acceleration mechanism further comprises a photoelectric switch (700), wherein the photoelectric switch (700) is arranged below the driving coil (300) and is activated when the falling armature (100) leaves the driving coil (300) to control the trigger switch (600).

7. The electromagnetic induction launch type release short section for the self-sealing plug according to claim 6 is characterized in that The oil pipe buckle short section (800) is arranged below the acceleration mechanism, and the inner circle of the oil pipe buckle short section (800) is provided with a second step (810); after the falling armature (100) enters the oil pipe buckle short section (800), the first step (140) of the falling armature (100) collides with the second step (810).

8. The electromagnetic induction launch type release nipple for the self-sealing plug according to claim 7 is characterized in that: The projectile seat (900) comprises a projectile seat upper section (930) and a projectile seat lower section (940); the projectile seat upper section (930) is inserted into the lower end of the oil pipe buckle short section (800); a projectile bayonet (910) is provided at the connection between the projectile seat upper section (930) and the projectile seat lower section (940); the diameter of the projectile bayonet (910) is smaller than the diameter of the projectile (200).

9. The electromagnetic induction launch type release nipple for the self-sealing plug according to claim 8 is characterized in that: The projectile seat (900) is arranged inside the coupling (1000) and connected to the coupling (1000); the lower section of the inner circle of the coupling (1000) is provided with a third step (1010), and the inner diameter of the third step (1010) is smaller than the outer diameter of the lower section (940) of the projectile seat.

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