RU2635929C1 - Reusable connection and detonation transmission unit for multibody perforating system - Google Patents

Abstract

FIELD: blasting.

SUBSTANCE: reusable connection and detonation transmission unit for the multibody perforating system comprises a transmitting and receiving parts having axially symmetric bodies connected pivotally. The transmitting part is made from the first body on which an outer bushing made in the form of a hollow cylinder with an internal cavity to install a hinge is installed, and a mounting port made perpendicular to the axis the receiving part entering the inner cavity. Protruding part of the receiving part is used as the hinge. The transmitting part comprises a rubber ring mounted on the end face of the first body against which the replaceable plate is pressed.

EFFECT: reliability of detonation transmission and possibility of multiple use of the unit.

7 cl, 15 dwg

Description

The invention relates to multi-body cumulative rock drills, lowered into the well on a geophysical cable or on a tubing string (tubing), using knots of connection and transmission of detonation in these perforation systems.

Known node connection and transmission of detonation in perforators according to the patent of the Russian Federation for the invention No. 2386793, IPC EV 43/117, publ. 04/20/2010 r.

This assembly contains a frame, an adapter, a detonating cord, a booster, a booster sleeve, which is made in the form of a disk and a cylindrical part with an axial hole for accommodating the booster.

The adapter has a through hole along the longitudinal axis with a cylindrical groove to accommodate the booster sleeve and detonating cord. The knock transmission unit is additionally equipped with a detonating cord, a booster, a booster bushing, a frame bushing.

The boosters are mounted on detonating cords, the additional booster sleeve is made in the form of a disk and a cylindrical part with an axial hole to accommodate the additional booster and is placed in the inner hole of the frame sleeve from the side of the cylindrical groove at the end of the frame sleeve to accommodate the disk.

A recess is made on the end side of the adapter, forming a cylindrical guide inside it, and a groove with an external diameter equal to the diameter of the recess is made on the end of the frame sleeve in contact with the end side of the adapter.

At the same time, an annular thickening is made outside the middle part of the carcass sleeve, which is integral with the carcass sleeve.

Disadvantages: the complexity of the design and its one-time use, the booster sleeve is made of rubber, and when a detonation pulse is transferred from one booster to another, the rubber sleeve is deformed and thereby the detonation pulse is reduced, which can lead to a failure in the transfer of detonation from the perforator to another perforator.

Known node connection and transmission of detonation in perforators according to the patent of the Russian Federation for the invention No. 2307237, IPC EV 43/1185, publ. 09/27/2007

This unit contains an adapter, a sleeve located in the inner hole of the adapter, a booster, a detonation cord, the end of which is connected to the booster. The booster is located in the sleeve.

The sleeve is made in the form of a disk and a cylindrical part with an axial hole. On the outer side of the cylindrical part of the sleeve are annular beads.

A partial longitudinal section is made at one end of the cylindrical part of the sleeve. The sleeve of the cumulative hammer drill detonation transmission device comprises a cylindrical part with an axial hole, a disk located on the outside of the cylindrical part.

The sleeve is provided with annular beads located on the outer side of the cylindrical part of the sleeve, and a partial longitudinal section of the cylindrical part of the sleeve from one end.

Disadvantages: the same.

Known node connection and transmission of detonation in perforators according to the patent of the Russian Federation for the invention No. 2422627, IPC EV 43/117, publ. 06/27/2011

This assembly contains a sleeve made in the form of a cylindrical part with an axial hole, a disk with a hole and a shoulder inside the hole.

It is equipped with a nut with an internal conical part, the cylindrical part at the end opposite to the disk is made with a petal collet. A thread is made on the outer side of the cylindrical part, onto which a nut is screwed, covering the inner cone-shaped part of the petal collet.

Disadvantages: design complexity, lack of protection against unauthorized operation, one-time use, lack of unification of the details of downhole perforators of various sizes, the booster sleeve is made of rubber and when the detonation pulse is transferred from one booster to another, the rubber sleeve is deformed and thereby weaken the detonation pulse, which can lead to to failure of the transmission of detonation from the punch to another punch.

Known multi-case perforation system and a node for connecting and transmitting information according to the patent of the Russian Federation for the invention No. 2519088, IPC EV 43/117, publ. 02/20/2014

This multi-case perforation system consists of separate perforator bodies, interconnected by a reusable unit with the function of mechanical flexible connection and transfer of detonation between perforator bodies.

Reusable knot connection and transmission of detonation, containing the transmitting and receiving parts, pivotally connected.

The disadvantages of the multi-case perforation system and the connection node are that all its parts are disposable and the reliability of knock transmission at the connection nodes is rather low.

Known cumulative perforator according to the patent of the Russian Federation for the invention No. 2081305, IPC EV 43/117, conv. Priority 01/23/1992, the prototype.

This reusable knot for connecting and transmitting detonation for a multi-case perforation system contains transmitting and receiving parts having axisymmetric housings pivotally connected, while the transmitting part is made of a first housing on which an external sleeve is installed, made in the form of a hollow cylinder with an internal cavity for mounting the hinge and with a side slot and a mounting hole made perpendicular to the axis of the receiving part, included in the internal cavity, while the role of the hinge is performed by acting th part of the receiving part.

The disadvantages of the connection node of this multicase perforation system are that all its parts are disposable and the reliability of knock transmission at the connection nodes is rather low.

Objectives of the invention: ensuring reliable transmission of a detonation pulse between the bodies of multi-case perforators and ensuring their reusability.

The technical result of the claimed solution is the possibility of reliable transmission of detonation in multihull perforation systems and ensuring their reusability.

The solution of these problems was achieved in a reusable knot for connecting and transmitting detonation for a multi-case perforation system containing transmitting and receiving parts having axisymmetric housings articulated in that the transmitting part is made of a first housing on which an external sleeve made in the form of a hollow cylinder is mounted with an internal cavity for mounting the hinge and with a side slot and a mounting hole made

perpendicular to the axis of the receiving part included in the internal cavity, the protruding part of the receiving part playing the role of a hinge, in that the transmitting part contains a rubber ring mounted on the end face of the first body, and a replaceable plate is pressed against the end face.

The replaceable plate can be made of a “T” -shaped cross-section and has a spherical recess at the end to direct the jet from the transfer charge to the center of rotation at any angles of mutual rotation of the transmitting and receiving parts by an angle α.

The angle of rotation can be selected from the condition:

α = 8 ... 10 °

In the first case, the first central channel can be made along its axis, the first central channel is stepped and contains a cylindrical cavity in which the transfer charge is installed, the first sleeve is installed in the first central channel, the washer is installed inside it, the first sleeve is made of metal, through the first the sleeve and washer passes the first detonating cord, then installed: the first booster and transfer charge.

The receiving part may consist of a second body, on the lateral surface of which there is an annular groove for fixing at the wellhead, also flats are made on the annular groove for twisting with a key into the upstream housing.

A conical hole can be made inside the protruding part of the second housing at the entrance to the second central channel, into which a conical sleeve made of plastic material is tightly pressed, repeating the shape of the conical hole.

In the second central channel, they can be installed sequentially behind the conical hole: a second booster, a second washer, a second sleeve, inside which a second detonating cord passes.

The invention is illustrated by the following drawings (Fig. 1 ... 15):

- in FIG. 1 is a view in longitudinal section of a reusable knot for connecting and transmitting detonation assembly,

- in FIG. 2 is a view in longitudinal section of a reusable knot for connecting and transmitting detonation, where the transmitting and receiving parts are rotated relative to each other,

- in FIG. 3 is a view in longitudinal section of the initiating block during descent on a geophysical cable,

- in FIG. 4 is a view in longitudinal section of the initiating block during the descent to the tubing,

- in FIG. 5 is a view of the formation of a multi-case perforation system during descent on a cable,

- in FIG. 6 is a view of the formation of a multi-body perforation system during descent to the tubing,

- in FIG. 7 shows a fragment of the transmitting part,

- in FIG. 8 is a view B, FIG. 7,

- in FIG. 9 shows the drilling rig,

- in FIG. 10 shows the transportation unit,

- in FIG. 11 shows the assembly process of a multi-body perforation system on a drilling

- in FIG. 12 shows a replacement plate

- in FIG. 13 is an adapter

- in FIG. 14 shows the process of lowering the multi-body perforation system on coiled tubing,

- in FIG. 15 shows the process of launching a multi-body perforation system on coiled tubing into a horizontal well.

Designations accepted in the description:

1. upstream housing

2. lower body

3. knot of connection and transmission of detonation,

4. initiating device

5. suspension means

6. transmitting part,

7. receiving part,

8. the first building,

9. outer sleeve,

10. thread

11. locking screw

12. the first central channel,

13. cylindrical cavity,

14. transfer charge

15. first sleeve,

16. washer,

17. the first detonating cord,

18. first booster,

19. butt,

20. a sealing rubber ring,

21. interchangeable plate

22. the internal cavity,

23. side slot

24. frame sleeve,

25. butt,

26. rubber sleeve,

27. second building,

28. side surface

29. ring groove,

30. flats,

31. second central channel,

32. protruding part,

33. conical hole,

34. conical sleeve,

35. second washer,

36. second booster,

37. second sleeve,

38. second detonating cord,

39. building,

40. bushing

41. rubber o-ring,

42. transfer charge

43. intermediate washer,

44. electric detonator

45. pressure washer,

46. sting

47. dielectric bushing,

48. building

49. bushing

50. interchangeable plate

51. rubber ring,

52. transfer charge

53. intermediate washer,

54. shock detonator,

55. pressure washer,

56. cable initiating head,

57. initiating unit,

58. the receiving part is adapted,

59. punch,

60. adapter,

61. tip,

62. geophysical cable,

63. tubing string,

64. initiating unit,

65. the receiving part of the connection node,

66. the transmitting part of the connection node,

67. rotary hammers,

68. tip,

69. mounting hole,

70. drilling rig,

71. oil rig

72. surface

73. well,

74. casing,

75. drill pipe storage warehouse,

76. wellhead retainer,

77. winch,

78. cable

79. transportation unit,

80. butt,

81. a cylindrical cavity,

82. ring groove,

83. sealing end

84. adapter

85. case,

86. channel

87. metal tube

88. the first frame sleeve,

89. detonating cord,

90. washer,

91. center hole

92. receiving booster,

93. transmitting booster,

94. bushing,

95. second frame sleeve,

96. o-rings,

97. coiled tubing,

98. coil tubing,

99. reservoir

100. vertical section,

101. horizontal section

102. transitional section.

Multicase perforation system (Fig. 1) contains several (at least two) cases. The invention is further illustrated by the example of the connection of two buildings: upstream 1 and downstream 2, connected by a knot connection and a detonation transmission 3. A knot connection and a knock transmission 3 can be made hinged. An initiating device 4 is attached to the uppermost upper housing 1, to which the suspension means 5 is attached.

The knot of connection and transmission of detonation 3 (Fig. 1) contains a transmitting part 6 and a receiving part 7, made axisymmetrically and pivotally connected.

The transmitting part 6 (Figs. 1 and 2) consists of a first housing 8, on which an external sleeve 9 is mounted, which is screwed by a thread 10 onto the first housing 8 and fixed with a locking screw 11.

In the first housing 8, a first central channel 12 is formed along its axis. The first central channel 12 is stepwise shaped and comprises a cylindrical cavity 13 in which a transfer charge 14 is installed.

In the first central channel 12, a first sleeve 15 is installed, inside of which a washer 16 is installed. The first sleeve 15 is made of metal. The first detonating cord 17 passes through the first bushing 15 and the washer 16. The following are installed: the first booster 18 and the transfer charge 14. The tightness of the cylindrical cavity 13 of the first casing 8 is ensured by a rubber sealing ring 20 mounted on the end face 19 of the first case 8. A replaceable one is pressed against the end face 19. plate 21.

For assembly on the outer sleeve 9 under the interchangeable plate 21 made a side slot 23.

The interchangeable plate 21 is made of a "T" -shaped cross-section and has a spherical recess of radius R1 on the end to direct the jet from the transfer charge to point A (center of rotation) at any angles of mutual rotation of the transmitting and receiving parts 6 and 7 by an angle α.

The optimal maximum allowable angle α of the mutual rotation of the receiving part 7 relative to the transmitting 6 (in all directions) is:

α = 7 ... 10 °.

On the other hand, concentrically to the first body 8, an upstream body 1 is installed, inside of which a frame sleeve 24 is installed, which contacts at the end face 25 of the first body 8. The upstream body 1 and the frame sleeve 24 are not included in the reusable knot connection and transmission unit.

A rubber sleeve 26 can be mounted concentrically to the transfer charge 14 to facilitate dismantling the transfer charge 14 after it is activated.

The receiving part 7 (Figs. 1 and 2) consists of a second body 27, on the side surface 28 of which there is an annular groove 29 for fixing at the wellhead, also flanges 30 are made on the annular groove 29 for twisting with a key into the upstream housing 1. Along the axis the second housing 27 is made of the second Central channel 31. The role of the hinge is performed by the protruding portion 32, having a shape close to spherical.

A conical hole 33 is made inside the protruding portion 32 of the second body 27 at the entrance to the second central channel 31, into which the conical sleeve 34 of plastic material is tightly pressed, repeating the shape of the conical hole 33. The conical sleeve 34 seals the inner cavity of the receiving part 7 and is a replaceable element. In the second central channel 31, a second washer 35 (Fig. 1), a second booster 36, a second sleeve 37, inside which a second detonating cord 38 passes, are installed sequentially behind the tapered hole 33.

The depth of penetration of the conical sleeve 34, depending on the angle of inclination of the joint, is selected so that at the maximum angle the cumulative stream of the transfer charge 14 passes through the center of the end face of the second booster 36.

The length L _{1 of the} conical hole 33 is selected from the condition:

L ₁ = (2.0 ... 3.0) d,

where L ₁ is the length of the conical hole 33,

d is the diameter of the channel behind this hole.

A reusable connection assembly device is also shown in FIG. 1. The detachable swivel connection of the receiving and transmitting parts provides not only the connection and disconnection of adjacent perforator bodies of the multi-body perforation system, but also the rotation of the bodies relative to each other by an angle α between the longitudinal axes of the bodies (Fig. 2).

It has been experimentally confirmed that when the transfer charge is triggered, the cumulative jet passes through the center of the end surface of the booster of the receiving part 7, ensuring a reliable operation of the booster, which then passes the detonation pulse through the detonating cord. After firing, the shot-through replaceable plate 21 is replaced in the transmitting part 6, and in the receiving part 7, the shot-through conical sleeve 34 is changed. The remaining elements of the reusable connection and detonation transfer unit 3 are secured by the design and strength of the material transmitting 6 and receiving 7 parts.

The initiating device 4 for working on the geophysical cable (Fig. 3) is made in the form of an initiating unit 57 and consists of a housing 39, a sleeve 40, a replaceable plate 21, a rubber sealing ring 41, a transfer charge 42, an intermediate washer 43, an electric detonator 44, a pressure washer 45, sting 46, sleeve dielectric 47.

The interchangeable plate 21 is made of a "T" -shaped in cross section and with a spherical segmented recess at the end, made of radius R ₁ .

Since only 2 ... 3 perforator bodies are lowered on the geophysical cable, it is possible to connect perforator bodies with adapters (Fig. 5).

During the descent to the tubing 63 (Fig. 4), an initiating block 64 is used, which is triggered by pressure or mechanical stress, it consists of a housing 48, a sleeve 49 screwed with a housing 48, a change of the plate 50 installed between them, a rubber sealing ring 51, installed under the interchangeable plate 50, the transfer charge 52, the intermediate washer 53, the shock detonator 54 and the pressure washer 55.

The interchangeable plate 50, as well as the interchangeable plate 21 are made of a "T" -shaped in cross section and with a spherical segmented recess at the end, made of radius R ₁ .

In FIG. 5 shows a diagram of a multi-case perforation system with a cable initiating head 56 (made uniform for all types of perforation systems and with a function of protection against unauthorized initiation), an initiating unit 57, a receiving part adapted 58, a perforator 59, an adapter 60, a ferrule 61, a geophysical cable 62.

In FIG. 6 is a diagram of a multi-body perforation system mounted on a tubing string 63. It contains an initiating unit 64, a receiving part of a connection unit 65, a transmitting part of a connection unit 66, perforators 67, a tip 68.

In FIG. 7 shows a fragment of the transmitting part, and in FIG. 8 is a view of B. Visible in FIG. 7, that the lower part of the inner cavity 22 is bounded by a spherical surface with a radius R ₂ .

In this case, the following conditions must be met:

R ₂ = R ₃ ,

Where

R ₂ is the radius of the sphere of the inner cavity 22,

R ₃ is the radius of the lower sphere of the protruding part 32 (Fig. 11).

In addition, the assembly condition must be met:

D ₂ ≥D ₁ ,

 Where

D ₂ - the diameter of the mounting hole 69 of the lateral slot 23,

D ₁ - the maximum diameter of the protruding part 32.

In FIG. Figure 9 shows the assembly process of a multi-case perforator on a drilling rig 70. The drilling rig 70 comprises a drilling tower 71 mounted on a surface 72. A well 73 has been drilled, which is cased by a casing 74. The drilling tower 71 has a storage pipe for drill pipes 75 where upstream and downstream housings are stored 1 and 2. The drilling rig is equipped with a wellhead retainer 76, a winch 77 with a cable 78, at the lower end of which a transport unit 79 is suspended (Figs. 9 and 10).

In FIG. 11 shows the assembly process of a multi-body perforation system on a drilling rig in more detail.

The downstream casing 2 is lowered into the well 73 and clamped with the wellhead retainer 76 vertically. The upstream casing 1 is connected to the downstream casing 2, moving horizontally, which facilitates the work of specialists serving the rig. Wellhead retainer 76 hold the downstream body 2 inside the well 73, cased casing 74.

In FIG. 12 is a more detailed drawing of the interchangeable plate 21 (interchangeable plate 50 has a similar design). It has at the end 80 a spherical recess (part of the sphere) made of radius R ₁ , a cylindrical cavity 81, an annular groove 82 and a sealing end 83. The optimal thickness of the jumper δ1 is selected from the relation:

δ ₁ = 2 ... 4 mm.

In FIG. 13 shows an adapter 84 for connecting upstream and downstream housings without the possibility of mutual rotation.

An adapter 84 is located between the upstream housing 1 and the downstream housing 2, which comprises a housing 85. Inside the housing 85, a metal tube 87 is installed in the channel 86, mounted on the first frame sleeve 88 with a detonating cord 89 with a washer 90 with a central hole 91, the diameter of which is smaller the diameter of the receiving booster 92. This does not allow you to move down the axis when the transmitting booster 93 is located, located in the sleeve 94, made of metal, which in turn is installed in the second frame in ulke 95 and sealed O-rings 96, is prevented from falling out of the sleeve 94 during tightening of an upper casing 1.

Between the boosters 92 and 93 should be a gap δ ₂ .

The optimal value of the gap from the installation conditions and the provision of temperature compensations:

δ ₂ = 1 ... 2 mm.

The adapter 84 should have a sufficient acceleration length

L ₂ = 120 to 200 mm,

it is necessary that the detonating cord 89 goes into stationary mode.

In addition to the descent of the multi-body perforation system on the tubing string 63, it can be run on the coiled tubing (flexible tubing).

Flexible tubing (CT) is a continuous steel pipe used to perform various work in a well operating under pressure.

Coiled tubing is available in diameters from 25.4 mm to 127.0 mm and various wall thicknesses according to the API5ST standard. The maximum length is 8000 meters.

DIS LLC supplies coiled tubing from the Baoji Petroleum Steel Pipe Co., Ltd (BSG) plant. Baoji Petroleum Steel Pipe Co .. Ltd (BSG) is a state-owned enterprise, part of China National Petroleum Corporation (CNPC). In 1958, the factory was founded and became the first large diameter spiral seam steel pipe (HSAW) manufacturer in China.

The CT version of FIG. 1 ... 15 is not shown.

A variant of the descent of the perforation system (Fig. 14) on coiled tubing 97 (a flexible metal pipe of small diameter) uncoiled from a coiled tubing coil 98 installed on the surface 72. The perforated system is installed in the area of the reservoir 99.

Coiled tubing (English Coiled tubing; flexible pipe string) is one of the promising and developing areas of specialized equipment for the gas and oil industry. It is based on the use of flexible continuous pipes, which replace traditional precast drill pipes when working inside wells. Due to their flexibility, such pipes are able to provide access even to the side and horizontal shafts; in addition, assembly / disassembly of the drill string is not required.

Coiled tubing is widely used in technological as well as repair and restoration work carried out on gas, oil and gas condensate wells. The technology was invented in the 1950s, it became widely used only in the late 1980s. It is cheaper and more environmentally friendly than classic columns.

One of the main limitations of classic coiled tubing is the inability to use rotation. Because of this, traditional rigs are often used to drill the main well, although there are coiled tubing drilling projects, including Rotating coiled tubing or TTRD.

In FIG. 15 shows the process of launching a multi-body perforation system on coiled tubing 97 into a horizontal well 73. Well 73 has a vertical section 100, a horizontal section 101 and a transition section 102.

PERFECTION SYSTEM OPERATION

During the descent, a triggering device 4 is installed in the upper part of the geophysical cable 62 (Fig. 5), to which the suspension means 5 are connected in the form of a geophysical cable 62. The triggering device 4, which is the initiating unit 57, is shown in more detail in FIG. 3. The assembly of the perforation system bodies is carried out as shown in FIG. 9.

During the descent to the tubing 63 (Fig. 6), an initiating block 64 is installed in the upper part, which is triggered by pressure or mechanical stress. In both cases, this initiating block 64 consists (Fig. 4) of a housing 48, a sleeve 49, a replaceable plate 50, a rubber ring 51, a transfer charge 52, an intermediate washer 53, an impact detonator 54, a pressure washer 55.

During the descent to the tubing 63, a multi-case perforation system is formed, the length of which can reach from 250 ... 500 m, depending on the size of the perforators, therefore reusable knot connection and transmission knots 3 are installed between the bodies of the perforators 1 and 2 (Fig. 1) (Fig. 6 ) Such reusable knots of connection and transmission of detonation 3 allow the use of multi-body perforation systems in wells with a complex geological profile.

When using multi-case perforation systems, the use of the proposed flexible connection unit allows to reduce the time of assembly and disassembly of perforation systems by connecting the receiving and transmitting parts without thread (Fig. 9). In this case, the receiving part 2 is held by the wellhead retainer 76 inside the well 73 cased by the casing 74.

In addition to lowering the multi-body perforation system on the tubing string 63, it can be run on the CT (flexible tubing), in FIG. 1 ... 15 is not shown.

A variant of the descent of the perforation system (Fig. 14) on coiled tubing 97 (a flexible metal pipe of small diameter), unwound from the coiled tubing coil 98, mounted on the surface 72.

This method is especially effective for horizontal wells (Fig. 15), which contain vertical 100 and horizontal 101 sections, conjugated by a transition section 102 with a sufficiently large radius R _min , so that the rotation of the nodes of the connection and transfer of detonation 3 by only 8 ... 10 ° ensured the passage of the whole perforation system in a horizontal section 101 of the well 73.

In this case, the condition for non-sticking of the perforation system in the transition section 102 is the ratio between the length L _{3 of the} body and its diameter D _to :

where L ₃ - the maximum length of the housing of the perforation system,

R _min - the minimum radius of curvature of the transition section,

D ₀ - the inner diameter of the casing,

D _to - the diameter of the housing of the perforation system,

Formula output:

L ₃ = 2 a, where a is the half of the dyne L ₃ ,

and ² = (R _min + D _o ) ² - (R _min -D _k ) ² ,

this gives the formula (1)

Example: When R _min = 15 m, D _o = 0.1 m and D _k = 0.07 m.

L ₃ = 2 m.

Claims (8)

1. A reusable knot for connecting and transmitting detonation for a multi-body perforation system, comprising transmitting and receiving parts having axisymmetric housings pivotally connected, the transmitting part is made of a first housing on which an external sleeve is installed, made in the form of a hollow cylinder with an internal cavity for mounting the hinge and with a side slot and a mounting hole made perpendicular to the axis of the receiving part, entering the internal cavity, the protruding part being the hinge riemnoy portion, characterized in that the transmitting part comprises a rubber ring mounted on the end of the first housing, and is pressed to the end face of the insert. 2. A reusable knot of connection and transmission of detonation for a multi-case perforation system according to claim 1, characterized in that the interchangeable plate is made of a "T" -shaped in cross section and has a spherical recess at the end to direct the jet from the transfer charge to the center of rotation for any the angles of mutual rotation of the transmitting and receiving parts by an angle α. 3. A reusable knot for connecting and transmitting detonation for a multi-case perforation system according to claim 2, characterized in that the angle of rotation is selected from the condition: α = 8 ... 10 ° 4. A reusable knot for connecting and transmitting detonation for a multi-case perforation system according to claim 1, characterized in that the first central channel is made along the axis in the first case, the first central channel is step-shaped and contains a cylindrical cavity in which the transfer charge is installed, in the first central channel has a first sleeve, inside of which a washer is installed, the first sleeve is made of metal, the first detonating cord passes through the first sleeve and the washer, then installed: the first boost p and the transmission charge. 5. A reusable knot for connecting and transmitting detonation for a multi-case perforation system according to claim 1, characterized in that the receiving part consists of a second body, on the side surface of which there is an annular groove for fixing at the wellhead, and flats for twisting with a key are also made on the annular groove in the upstream building. 6. A reusable knot for connecting and transmitting detonation for a multi-case perforation system according to claim 1, characterized in that a conical hole is made inside the protruding part of the second body at the entrance to the second central channel, into which the conical sleeve of plastic material is tightly pressed, repeating the shape of the conical hole . 7. A reusable knot for connecting and transmitting detonation for a multi-case perforation system according to claim 1, characterized in that the second central channel is installed sequentially behind a conical hole: a second booster, a second washer, a second sleeve, inside which a second detonating cord passes.

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