Large-tonnage cutting type explosive bolt with double separation surfaces

Abstract

The invention discloses a large-tonnage cutting type explosive bolt with double separation surfaces. The large-tonnage cutting type explosive bolt comprises a first blanking cap, a second blanking cap, a first bolt body, a second bolt body, a first filling piece, a second filling piece, a first protective cap, a second protective cap, a third bolt body, a first separation assembly and a second separation assembly. Wherein the first separation assembly is arranged in a concave cavity in one side of the third bolt body, and the first bolt body is connected with the third bolt body; the second separation assembly is arranged in a concave cavity in the other side of the third bolt body, and the second bolt body is connected with the third bolt body; the first filling piece is arranged in the first bolt body; the second filling piece is arranged in the second bolt body; the first blanking cap is connected with the first bolt body; the second blanking cap is connected with the second bolt body; the first protective cap sleeves the outer surface of the first bolt body; and the second protective cap sleeves the outer surface of the second bolt body. According to the explosive bolt, the problem that an existing explosive bolt is insufficient in bearing capacity and redundant separation capacity is solved.

Description

Technical Field

[0001] The invention belongs to the technical field of explosive bolts, and in particular relates to a large-tonnage double-separation-surface cutting-type explosive bolt. Background Art

[0002] Explosive bolts are pyrotechnic devices that rely on explosives to separate from the preset separation surface of the bolt body. They are important connection and unlocking components, mainly used for connection and unlocking of aircraft pre-separation surfaces. Depending on the use environment, the relevant requirements for explosive bolts are also different. Generally, explosive bolts are required to have a short action time, high synchronization, reliable operation, strong environmental adaptability and high safety of use.

[0003] Traditional explosive bolts are mainly divided into shear-type explosive bolts and piston-push rod-type explosive bolts according to their structural forms. The working principles of the two structures of explosive bolts are basically the same, except that the settings of the pre-separation surface are different. However, with the continuous promotion of the application scope of explosive bolts and the continuous increase in model application requirements, the demand for explosive bolts with higher load-bearing capacity has been put forward. However, due to the limitations of structural design and material properties of load-bearing parts, traditional explosive bolts cannot meet the structural design of ultra-large load explosive bolts. In addition, the existing explosive bolts are all non-redundant explosive bolts, which have lower reliability than redundant explosive bolts.

[0004] Patent ZL201010049928.0 is named as cutting-separation explosive bolt, which consists of a short-circuit part, an electrical connection socket, a mounting screw, a mounting seat I, a mounting seat II, an O-shaped rubber sealing ring, a mounting nut, a bolt body, a filling part I, a clamping nut I, a connecting nut, a clamping nut II, an insensitive electric detonator, a detonator tube, and a cutting ring. When the electric detonator receives an electrical signal, it works to detonate the detonator tube, and the detonator tube detonates the cutting ring, which outputs detonation energy radially to separate the bolt body. The explosive bolt has only a single cutting ring, which is a non-redundant structure with a load-bearing capacity of no more than 100 tons. It is also a non-redundant explosive bolt, which has a lower reliability than redundant explosive bolts and is difficult to be used in carrier separation and unlocking with high load-bearing capacity and reliability requirements.

[0005] The above patent is limited by the structure of the device and cannot achieve redundant separation of the explosive bolts. It has the following shortcomings: the explosive bolt is equipped with an internal cutting ring, which poses a risk of single-point failure, and reliability can only be improved by increasing the number of detonation sources; the explosive bolt has a low load-bearing capacity and cannot meet the load-bearing capacity requirements of more than 100 tons.

[0006] With the development of aerospace technology, facing the application conditions of large load-bearing capacity and high reliability of space launchers, the requirements for the load-bearing and reliability of explosive bolts are becoming higher and higher. Traditional explosive bolts are not suitable for the high-load and high-reliability application needs of large-tonnage launchers. Summary of the invention

[0007] The technical problem solved by the present invention is: to overcome the deficiencies of the prior art, to provide a large-tonnage double-separation-surface cutting-type explosive bolt, and to overcome the deficiencies in the bearing capacity and redundant separation capacity of the prior explosive bolts.

[0008] The objective of the present invention is achieved through the following technical scheme: A large-tonnage double-separation-surface cutting-type explosive bolt, comprising: a first plugging cover, a second plugging cover, a first bolt body, a second bolt body, a first filling piece, a second filling piece, a first protective cap, a second protective cap, a third bolt body, a first separation assembly and a second separation assembly; wherein, the first separation assembly is arranged in a concave cavity on one side of the third bolt body, and one end of the first bolt body is connected to one end of the third bolt body; the second separation assembly is arranged in a concave cavity on the other side of the third bolt body, and one end of the second bolt body is connected to the other end of the third bolt body; the first filling piece is arranged inside the first bolt body; the second filling piece is arranged inside the second bolt body; the first plugging cover is connected to the other end of the first bolt body; the second plugging cover is connected to the other end of the second bolt body; the first protective cap is sleeved on the outer surface of the first bolt body; the second protective cap is sleeved on the outer surface of the second bolt body.

[0009] In the above-mentioned large-tonnage double-separation-surface cutting explosive bolt, the first separation component and the second separation component have the same structure, both including a clamping nut, a connecting nut, a connecting seat, a buffer pad, a cutting ring, a detonator and an electric detonator; wherein the buffer pad is connected to one side of the connecting seat; the outer peripheral end of the connecting seat is connected to the inner wall of the concave cavity of the third bolt body; one end of the cutting ring is connected to the connecting seat; the detonator is installed in the mounting hole at the other end of the cutting ring; one end of the electric detonator is connected to the other end of the cutting ring; the outer peripheral end of the clamping nut is connected to the inner wall of the concave cavity of the third bolt body; and the clamping nut is pressed against the cutting ring; the connecting nut is connected to the cutting ring; and the connecting nut is fitted with the clamping nut; the cable of the electric detonator passes through the first filling piece and the first protective cap in sequence, or the cable of the electric detonator passes through the second filling piece and the second protective cap in sequence.

[0010] In the above-mentioned large-tonnage double-separation-surface cutting-type explosive bolt, both the first separation assembly and the second separation assembly further include a first O-ring; wherein, one end of the electric detonator is sleeved with the first O-ring and then installed in the cutting ring.

[0011] In the above-mentioned large-tonnage double-separation-surface cutting-type explosive bolt, both the first separation assembly and the second separation assembly further include a second O-ring; wherein the second O-ring is disposed between the clamping nut and the cutting ring.

[0012] In the above-mentioned large-tonnage double-separation-surface cutting-type explosive bolt, both the first separation assembly and the second separation assembly further include a third O-ring; wherein the third O-ring is disposed between the clamping nut and the cutting ring.

[0013] In the above-mentioned large-tonnage double-separation-surface cutting explosive bolt, the cutting ring includes a detonating seat, a pressure block, a focusing cover and a focusing charge; wherein the detonating seat is connected to one end of the focusing cover; the pressure block is connected to the other end of the focusing cover; and the focusing charge is arranged inside the focusing cover.

[0014] In the above-mentioned large-tonnage double-separation-surface cutting explosive bolt, the shaped charge is a combination of a central explosive column and a shaped charge; wherein the length-to-diameter ratio L / D of the central explosive column ranges from 0.8 to 1.2.

[0015] In the above-mentioned large-tonnage double-separation-surface cutting-type explosive bolt, the detonator seat comprises a T-shaped cylindrical structure and a boss; wherein the boss is integrally connected to the upper surface of the T-shaped cylindrical structure; the cross-section of the boss is an isosceles trapezoid; and the upper surface of the detonator seat is the contact surface with the shaped charge.

[0016] In the above-mentioned large-tonnage double-separation-surface cutting explosive bolt, the materials of the first bolt body, the second bolt body and the third bolt body are all 0Cr13Ni8Mo2Al precipitation-hardened stainless steel, and the hardness of the first bolt body, the second bolt body and the third bolt body is HRC40-45.

[0017] In the above-mentioned large-tonnage double-separation-surface cutting-type explosive bolt, the materials of the detonator seat and the pressing block are both 1Cr11Ni2W2MoV steel or 30CrMnSiA steel or Cr17Ni2, and the hardness of the detonator seat and the pressing block is HRC32-38.

[0018] In the above-mentioned large-tonnage double-separation-surface cutting-type explosive bolt, the large-tonnage double-separation-surface cutting-type explosive bolt is characterized in that when the explosive bolt is working, the stress generated by the cutting ring is obtained by the following formula:

[0019] σ1=P·r 2 / (R 2 -r 2 );

[0020] σ2=P·r 2 (R 2 +r2 ) / [b 2 (R 2 -r 2 )];

[0021] σ3=-P;

[0022] b = r + 0.5 × (R - r);

[0023] Among them, σ1 is the axial stress, σ2 is the hoop stress, σ3 is the radial stress, P is the pressure generated by the electric initiator after operation, r is the inner diameter of the third bolt body, R is the outer diameter of the distribution circle of the weakest part of the third bolt body, and b is the median diameter.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] (1) The present invention utilizes the energy-gathering cutting effect of explosive charge, which can meet various bearing capacity requirements at the pre-separation surface to the maximum extent, and has an extremely wide range of applicable bearing capacity;

[0026] (2) The cutting ring of the present invention is a shaped charge structure, which utilizes the shaped cutting effect to form a metal jet in a continuous "emission" shape in the radial plane to perform radial cross-section cutting and separation on the bolt body from the inside to the outside. It can be applied to cylindrical load-bearing structures with uniform wall thickness or load-bearing structures with non-uniform wall thickness or weakened groove-type load-bearing structures with stress concentration effect on the outer surface, as well as various forms of connection structures of the same or different materials with circumferential discontinuous surfaces or radial multiple layers at the separation part. As long as the maximum separation wall thickness at the separation surface is within the effective cutting and separation thickness range of the cutting ring, the cutting and separation function can be achieved;

[0027] (3) The cutting and separating ring of the present invention is only related to the thickness of the separating part of the bolt body in the process of completing the separation function. The slight bending deformation of the bolt body in the process of bearing the bending moment has no effect on the separation function of the product itself. However, the conventional piston push rod type explosive bolt has the hidden danger of the piston push rod being stuck and unable to move when the bolt body is slightly deformed under excessive bending moment;

[0028] (4) The separation object of the present invention is a steel rod, which has the characteristics of high tensile strength and high material density, and the separation thickness is relatively thick. Therefore, the energy-gathering cover is made of copper material with high material density, low compressibility, good plasticity, high gasification temperature, which is conducive to forming a slender and unbroken metal jet and has good processing technology. The charge of the cutting ring is RDX explosive with high detonation energy, high filling density and good stability to ensure sufficient jet energy density;

[0029] (5) The shaped charge structure of the present invention is a combination of a central booster column and a shaped charge, which minimizes the charge diameter of the product while ensuring the working reliability of the product. Through the ingenious combination of the shaped charge and the booster column, the structural size of the product is reduced, the charge amount is reduced, and the energy efficiency ratio of the agent is improved;

[0030] (6) The center of the shaped charge of the present invention is a booster column structure with a reasonable aspect ratio, which can effectively detonate and initiate the booster tube, thereby improving the energy efficiency ratio of the charge;

[0031] (7) The present invention provides a fully redundant and separated pyrotechnic system with dual detonators, dual detonators and dual cutting rings. Either side can complete the predetermined function when powered on, and the two sides do not interfere with each other.

[0032] (8) The central portion of the shaped charge of the present invention is a booster column structure with a reasonable aspect ratio, which can effectively detonate and initiate the booster tube, thereby improving the energy efficiency ratio of the charge. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Moreover, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0034] Figure 1 It is a structural schematic diagram of a large-tonnage double-separation-surface cutting explosive bolt provided by an embodiment of the present invention;

[0035] Figure 2 It is a structural schematic diagram of a large-tonnage double-separation-surface cutting-type explosive bolt separation assembly provided by an embodiment of the present invention;

[0036] Figure 3 is a schematic structural diagram of a cutting ring provided by an embodiment of the present invention;

[0037] Figure 4 It is a schematic diagram of the structure of a detonator seat for forming shaped charge provided by an embodiment of the present invention;

[0038] Figure 5 It is a schematic diagram of a briquette structure for forming shaped charge provided by an embodiment of the present invention;

[0039] Figure 6 It is a schematic diagram of the structure of a metal energy-gathering cover for forming shaped charges provided by an embodiment of the present invention; DETAILED DESCRIPTION

[0040] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present disclosure and to be able to fully convey the scope of the present disclosure to those skilled in the art. It should be noted that, in the absence of conflict, the embodiments of the present invention and the features described in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0041] Figure 1 It is a structural schematic diagram of a large-tonnage double-separation-surface cutting explosive bolt provided by an embodiment of the present invention; Figure 2 Schematic diagram of the structure of a large-tonnage double separation surface cutting explosive bolt separation assembly provided by an embodiment of the present invention. Figure 1 and Figure 2 As shown, the large-tonnage double-separation-surface cutting explosive bolt comprises: a first plugging cover 11, a second plugging cover 12, a first bolt body 2, a second bolt body 3, a first filling piece 4, a second filling piece 5, a first protective cap 61, a second protective cap 62, a third bolt body 7, a first separation assembly and a second separation assembly; wherein the first separation assembly is arranged in a concave cavity on one side of the third bolt body 7, and one end of the first bolt body 2 is connected to one end of the third bolt body 7; the second separation assembly is arranged in a concave cavity on the other side of the third bolt body 7, and one end of the second bolt body 3 is connected to the other end of the third bolt body 7; the first filling piece 4 is arranged inside the first bolt body 2; the second filling piece 5 is arranged inside the second bolt body 3; the first plugging cover 11 is connected to the other end of the first bolt body 2; the second plugging cover 12 is connected to the other end of the second bolt body 3; the first protective cap 61 is sleeved on the outer surface of the first bolt body 2; the second protective cap 62 is sleeved on the outer surface of the second bolt body 3.

[0042] like Figure 2As shown, the first separation component and the second separation component have the same structure, both of which include a clamping nut 8, a connecting nut 9, a connecting seat 10, a buffer pad 11, a cutting ring 12, a detonator 13 and an electric detonator 17; wherein the buffer pad 11 is connected to one side of the connecting seat 10; the outer peripheral end of the connecting seat 10 is connected to the inner wall of the concave cavity of the third bolt body 7; one end of the cutting ring 12 is connected to the connecting seat 10; the detonator 13 is installed in the mounting hole at the other end of the cutting ring 12; one end of the electric detonator 17 is connected to the other end of the cutting ring 12; the outer peripheral end of the clamping nut 8 is connected to the inner wall of the concave cavity of the third bolt body 7; and the clamping nut 8 is pressed against the cutting ring 12; the connecting nut 9 is connected to the cutting ring 12; and the connecting nut 9 is fitted with the clamping nut 8; the cable of the electric detonator 17 passes through the first filling piece 4 and the first protective cap 61 in sequence, or the cable of the electric detonator 17 passes through the second filling piece 5 and the second protective cap 62 in sequence.

[0043] like Figure 2 As shown, both the first separation assembly and the second separation assembly further include a first O-ring 14 ; wherein one end of the electric detonator 17 is sleeved with the first O-ring 14 and then installed in the cutting ring 12 .

[0044] like Figure 2 As shown, both the first separation assembly and the second separation assembly further include a second O-ring 15 ; wherein the second O-ring 15 is disposed between the compression nut 8 and the cutting ring 12 .

[0045] like Figure 2 As shown, both the first separation assembly and the second separation assembly further include a third O-ring 16 ; wherein the third O-ring 16 is disposed between the compression nut 8 and the cutting ring 12 .

[0046] After applying epoxy glue on the bonding surface of the connecting seat 10, install the buffer pad 11 on the connecting seat 10; apply an appropriate amount of epoxy glue on the outer cylindrical surface of the detonator 13 and install it in the mounting hole on one side of the cutting ring 12. After the first O-shaped rubber sealing ring 14 is put on the output end of the electric detonator 17, screw it into the cutting ring 12; screw the cutting ring 12 into the connecting seat 10, and screw the connecting seat 10 into the third bolt body 7; apply grease on the clamping nut 8, then install the second O-shaped rubber sealing ring 15 and the third O-shaped rubber sealing ring 16 into the clamping nut 8, and screw the clamping nut 8 into the third bolt body 7; connect the connecting nut 9 is screwed into the cutting ring 12; the first bolt body 2 is screwed into one side of the third bolt body 7, the second bolt body 3 is screwed into the other side of the third bolt body 7, and then the first filler 4 is installed into the first bolt body 2, and the second filler 5 is installed into the second bolt body 3; the first plugging cover 11 is screwed into the first bolt body 2, the first plugging cover 11 is screwed into the first bolt body 3, and the joint between the plugging cover 1 and the cable of the electric detonator 17 is filled with silicone rubber; finally, the first protective cap 61 is screwed into the external thread of the first bolt body 2, and the second protective cap 62 is screwed into the external thread of the second bolt body 3, and is fixed with a lead seal. The bolt body is provided with a lead sealing hole and the arrow body structure is sealed to prevent loosening.

[0047] When receiving the separation signal from the rocket control system, the electric detonator on one side works and outputs detonation energy to detonate the detonator tube. The detonator tube outputs detonation energy and then detonates the cutting ring. The cutting ring works to output a metal jet to separate the bolt body.

[0048] The function of the cutting explosive bolt is: before working, it plays a role in connecting the pre-separation surface on the aircraft. After working, the explosive in the explosive bolt explodes to form a concentrated energy cutting jet, which separates the explosive bolt from the pre-separation surface and completes the unlocking of the pre-separation surface on the aircraft.

[0049] When the explosive bolt receives the separation signal, the built-in electric detonator detonates and outputs detonation energy to detonate the detonator tube under the energy stimulation of the rated working current. The detonator tube then detonates the agent in the cutting ring and forms a concentrated metal jet, which cuts the explosive bolt shell along the pre-separation surface to achieve the separation of the explosive bolt. The product is designed to be redundant. Any detonator working and detonating any detonator tube can complete the predetermined function. When the product is working on the arrow, the detonator on one side is energized first. After the cutting ring on this side works, the detonator on the other side is energized according to the overall timing control, so that the cutting ring on the other side works.

[0050] like Figure 3 As shown, the cutting ring 12 includes a detonating seat 18, a pressure block 19, a focusing hood 20 and a shaped charge 21; wherein the detonating seat 18 is connected to one end of the focusing hood 20; the pressure block 19 is connected to the other end of the focusing hood 20; and the shaped charge 21 is arranged inside the focusing hood 20.

[0051] like Figure 3 As shown, the cutting ring 12 of this embodiment includes a detonating seat 18, a pressing block 19, an energy-gathering cover 20, and an energy-gathering charge 21. The energy-gathering charge 20 is molded by applying pressure to the detonating seat 18 and the pressing block 19 through a special structural pressing tool, and is symmetrically pressed twice under the constraint of the energy-gathering cover 20. The detonating seat 18 and the pressing block 19 are fixed on both sides of the energy-gathering cover 20 by curling and sealing, and epoxy glue is applied to bond them. The detonating seat 18 is provided with mounting holes for the detonator tube and the insensitive electric detonator. The detonating seat 18 and the pressing block 19 are respectively placed on both sides of the energy-gathering charge, and are connected and fixed by the curling bending deformation force of the two ends of the energy-gathering cover, and the connecting seams are sealed by applying epoxy glue.

[0052] The structure of the shaped charge 21 after compression molding is a combination of a central explosive column and a shaped charge. While ensuring the working reliability of the product, the charge diameter of the product is minimized as much as possible. Through the ingenious combination of the shaped charge and the explosive column, the structural size of the product is reduced, the charge amount is reduced, and the energy efficiency ratio of the agent is improved. At the same time, the center of the shaped charge is made into a explosive column structure with a reasonable aspect ratio, which simplifies the product structure. The shaped charge 21 can be made of RDX, and the aspect ratio range of the central explosive column is L / D=0.8~1.2, generally about 1 (such as Figure 3 shown).

[0053] The pre-separation surface corresponding to the cutting ring 12 can be a cylindrical load-bearing structure with uniform wall thickness, a load-bearing structure with non-uniform wall thickness, or a weakened groove-type load-bearing structure with stress concentration effect on the outer surface.

[0054] The shaped charge 21 is a combination of a central booster column and a shaped charge; wherein the length-to-diameter ratio L / D of the central booster column is in the range of 0.8 to 1.2.

[0055] The electric detonator and the central explosive column transmit the detonation signal through the channel. The constraint relationship between the electric detonator and the channel is as follows:

[0056]

[0057] Where P is the pressure generated by the electric initiator after operation, m n is the charge mass of several agents in the electric detonator, f n is the powder force value of several kinds of agents in the electric detonator, and V is the channel volume.

[0058] Effect: This formula makes the detonation signal transmission effect good.

[0059] When the explosive bolt is working, the bolt body is subjected to the action of high temperature and high pressure gas. The bolt body must have sufficient strength except for the separation surface. The constraint relationship between the cutting ring and the bolt body is as follows:

[0060] σ1=P·r 2 / (R 2 -r 2 )

[0061] σ2=P·r 2 (R 2 +r 2 ) / [b 2 (R 2 -r 2 )]

[0062] σ3=-P

[0063] Among them, σ1 is the axial stress, σ2 is the hoop stress, σ3 is the radial stress, r is the inner diameter of the bolt body, R is the outer diameter of the distribution circle of the weakest part of the bolt body, b is the median diameter, and b=r+0.5×(R-r).

[0064] Effect, through this formula the bolt body has sufficient strength.

[0065] When the explosive bolt is working, the bolt body plays a bearing role and must have sufficient breaking load. The relationship between the bolt body and the load is as follows: F = πk (D 2 -d 2 )δ b / 4;

[0066] Where k is the correction coefficient, δ b D is the outer diameter of the bolt body and d is the tensile strength of the material. This formula is used to ensure that the bolt body has sufficient breaking load.

[0067] The separation thickness of the cutting ring from the bolt body is composed of two parts: "penetration depth + fracture extension". According to previous engineering application experience, the penetration depth of low-strength materials (such as aluminum alloy) should be greater than 55%. In order to achieve a penetration depth of more than 55%, the constraint relationship between the detonating cord and the compartment is as follows:

[0068] L=τ1×(bk) / cos(α / 2)>55%×Y

[0069] Among them, L is the separation thickness, τ1 is the empirical coefficient between the length of the bevel edge with charge and the jet length, b is the height of the energy focusing angle, k is the thickness of the back shell, α is the energy focusing angle, and Y is the thickness of the bolt body.

[0070] like Figure 4 As shown, the detonator seat 18 includes a T-shaped cylindrical structure and a boss; wherein the boss is integrally connected to the upper surface of the T-shaped cylindrical structure; the cross-section of the boss is an isosceles trapezoid; and the upper surface of the detonator seat 18 is the contact surface with the shaped charge.

[0071] like Figure 4As shown, the special shape detonator for forming shaped charge in this embodiment is a truncated cone structure, that is, its main body is a T-shaped cylindrical structure, a truncated cone protrudes from the center of the T-shaped upper surface, the cross-section of the truncated cone is an isosceles trapezoid, the upper surface of the truncated cone and the T-shaped cylinder are the contact surfaces with the shaped charge 21, the material is 1Cr11Ni2W2MoV steel, and there is a metal partition body with a thickness of 0.45mm to 0.55mm between the central part and the booster tube, which separates the booster tube 13 from the shaped charge 21. On the one hand, it ensures that the booster tube can reliably detonate and transmit the shaped charge, and on the other hand, it can ensure that the shaped charge is in a completely sealed environment, thereby improving the environmental adaptability.

[0072] like Figure 5 As shown, the special shape pressing block used for forming the shaped charge in this embodiment is a truncated cone structure, that is, its main body is a T-shaped cylindrical structure, a truncated cone protrudes from the center of the T-shaped upper surface, the cross-section of the truncated cone is an isosceles trapezoid, and the upper surface of the truncated cone and the T-shaped cylinder are the contact surfaces with the shaped charge 21, and the material is 1Cr11Ni2W2MoV steel, which can ensure that the shaped charge is in a completely sealed environment, thereby improving the environmental adaptability.

[0073] like Figure 6 As shown, the special shape metal energy focusing cover 20 of this embodiment for improving the energy focusing jet effect is a "V"-shaped thin-walled circular ring structure with a through hole in the middle. The material is copper, silver, aluminum, lead and their alloys. T2 copper is the best in terms of cost and effect.

[0074] The detonating elements (insensitive electric detonators and booster tubes) of this embodiment use insensitive bridge-belt electric detonators to meet the safety performance requirements of GJB344A-2005 "General Specifications for Insensitive Electric Detonators" for electric pyrotechnic products of 1A1W5min without ignition or failure, and at the same time have anti-static, anti-radio frequency and strong electromagnetic environment adaptability.

[0075] The materials of the first bolt body 2 , the second bolt body 3 and the third bolt body 7 are all 0Cr13Ni8Mo2Al precipitation hardened stainless steel, and the hardness of the first bolt body 2 , the second bolt body 3 and the third bolt body 7 is all HRC40-45.

[0076] The materials of the detonator seat 18 and the pressing block 19 are both 1Cr11Ni2W2MoV steel or 30CrMnSiA steel or Cr17Ni2, and the hardness of the detonator seat 18 and the pressing block 19 is HRC32-38.

[0077] The materials of the clamping nut 8, the connecting nut 9 and the connecting seat 10 are all 30CrMnSiA steel.

[0078] This embodiment uses the energy-gathering cutting effect of explosive charges to meet various bearing capacity requirements at the pre-separation surface to the maximum extent, and has an extremely wide range of applicable bearing capacity.

[0079] The cutting ring of the present embodiment is a shaped charge structure, which utilizes the shaped cutting effect to form a metal jet in a continuous "emission" shape in the radial plane to perform radial cross-section cutting and separation on the bolt body from the inside to the outside. It can be applied to cylindrical load-bearing structures with uniform wall thickness on the pre-separation surface, load-bearing structures with non-uniform wall thickness, or weakened groove-type load-bearing structures with stress concentration effect on the outer surface, as well as various forms of connection structures of the same or different materials with circumferential discontinuous surfaces or radial multiple layers of separation parts. As long as the maximum separation wall thickness at the separation surface is within the effective cutting and separation thickness range of the cutting ring, the cutting and separation function can be achieved.

[0080] In the process of completing the separation function, the cutting and separation ring of this embodiment is only related to the thickness of the separation part of the bolt body. The slight bending deformation of the bolt body when subjected to bending moment has no effect on the separation function of the product itself. However, in the traditional piston push rod type explosive bolt, there is a hidden danger that the piston push rod will be stuck and unable to move when the bolt body is subjected to excessive bending moment and has slight deformation.

[0081] The detonating element of this embodiment uses an insensitive bridge belt type electric detonator to meet the safety performance requirements of electric pyrotechnics 1A1W5min without ignition and failure, and at the same time has anti-static, anti-radio frequency and strong electromagnetic environment adaptability.

[0082] The separation object in this embodiment is a steel rod, which has the characteristics of high tensile strength and high material density, and the separation thickness is relatively thick. Therefore, the energy-gathering hood is made of copper material with high material density, low compressibility, good plasticity, high vaporization temperature, which is conducive to forming a slender and unbroken metal jet and has good processing technology. The cutting ring is charged with RDX explosive with high detonation energy, high filling density and good stability to ensure sufficient jet energy density.

[0083] The shaped charge structure of this embodiment is a combination of a central explosive column and a shaped charge. While ensuring the working reliability of the product, the charge diameter of the product is minimized as much as possible. Through the ingenious combination of the shaped charge and the explosive column, the structural size of the product is reduced, the charge amount is reduced, and the energy efficiency ratio of the agent is improved.

[0084] This embodiment requires a metal partition body with a thickness of 0.45mm to 0.55mm between the detonator tube and the shaped charge. On the one hand, it ensures that the detonator tube can reliably detonate and transmit the shaped charge. On the other hand, it ensures that the shaped charge is in a completely sealed environment, thereby improving environmental adaptability.

[0085] The central part of the shaped charge in this embodiment is a booster column structure with a reasonable aspect ratio, which can effectively detonate and initiate the booster tube, thereby improving the energy efficiency ratio of the charge.

[0086] This embodiment provides a completely redundant and separated pyrotechnic system with dual detonators, dual detonators and dual cutting rings. Either side can complete the predetermined function when powered on, and the two sides do not interfere with each other.

[0087] The central part of the shaped charge in the embodiment is a booster column structure with a reasonable aspect ratio, which can effectively detonate and initiate the booster tube, thereby improving the energy efficiency ratio of the charge.

[0088] In summary, this embodiment can withstand large axial and radial loads before the explosive bolts work, has the characteristics of wide adaptability of load-bearing capacity and bending moment resistance, and strong environmental adaptability. It can be widely used in aircraft stage separation, fairing separation, launch tube cover ejection, head body separation and other fields such as satellites and spacecraft.

[0089] Although the present invention has been disclosed as above in the form of a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art may make possible changes and modifications to the technical solution of the present invention by using the methods and technical contents disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the protection scope of the technical solution of the present invention.

Claims

1. A large-tonnage double-separation-surface cutting explosive bolt, characterized in that include: A first blocking cover (11), a second blocking cover (12), a first bolt body (2), a second bolt body (3), a first filling piece (4), a second filling piece (5), a first protective cap (61), a second protective cap (62), a third bolt body (7), a first separation assembly and a second separation assembly; wherein: The first separation assembly is arranged in a concave cavity on one side of the third bolt body (7), and one end of the first bolt body (2) is connected to one end of the third bolt body (7); The second separation assembly is arranged in the concave cavity on the other side of the third bolt body (7), and one end of the second bolt body (3) is connected to the other end of the third bolt body (7); The first filling piece (4) is arranged inside the first bolt body (2); The second filling piece (5) is arranged inside the second bolt body (3); The first blocking cover (11) is connected to the other end of the first bolt body (2); The second blocking cover (12) is connected to the other end of the second bolt body (3); The first protective cap (61) is sleeved on the outer surface of the first bolt body (2); The second protective cap (62) is sleeved on the outer surface of the second bolt body (3).

2. The large-tonnage double-separation-surface cutting explosive bolt according to claim 1 is characterized in that: The first separation assembly and the second separation assembly have the same structure, and both comprise a compression nut (8), a connection nut (9), a connection seat (10), a buffer pad (11), a cutting ring (12), a detonator (13) and an electric detonator (17); wherein: The buffer pad (11) is connected to a side surface of the connecting seat (10); The outer peripheral end of the connecting seat (10) is connected to the inner wall of the concave cavity of the third bolt body (7); One end of the cutting ring (12) is connected to the connecting seat (10); The detonator tube (13) is installed in the installation hole at the other end of the cutting ring (12); One end of the electric detonator (17) is connected to the other end of the cutting ring (12); The outer peripheral end of the clamping nut (8) is connected to the inner wall of the concave cavity of the third bolt body (7); and the clamping nut (8) is pressed against the cutting ring (12); The connecting nut (9) is connected to the cutting ring (12); and the connecting nut (9) is in close contact with the clamping nut (8); The cable of the electric detonator (17) passes through the first filling piece (4) and the first protective cap (61) in sequence, or the cable of the electric detonator (17) passes through the second filling piece (5) and the second protective cap (62) in sequence.

3. The large-tonnage double-separation-surface cutting explosive bolt according to claim 1 is characterized in that: The first separation assembly and the second separation assembly both further include a first O-ring (14); wherein, One end of the electric detonator (17) is covered with a first O-ring (14) and then installed in the cutting ring (12).

4. The large-tonnage double-separation-surface cutting explosive bolt according to claim 1 is characterized in that: The first separation assembly and the second separation assembly both further include a second O-ring (15); wherein the second O-ring (15) is arranged between the clamping nut (8) and the cutting ring (12).

5. The large-tonnage double-separation-surface cutting explosive bolt according to claim 1 is characterized in that: The first separation assembly and the second separation assembly both further include a third O-ring (16); wherein the third O-ring (16) is arranged between the clamping nut (8) and the cutting ring (12).

6. The large-tonnage double-separation-surface cutting explosive bolt according to claim 1 is characterized in that: The cutting ring (12) comprises a detonating seat (18), a pressing block (19), a shaped charge (20) and a shaped charge (21); wherein: The detonating seat (18) is connected to one end of the energy collecting cover (20); The pressing block (19) is connected to the other end of the energy gathering cover (20); The shaped charge (21) is arranged inside the shaped cover (20).

7. The large-tonnage double-separation-surface cutting explosive bolt according to claim 6 is characterized in that: The shaped charge (21) is a combination of a central booster column and a shaped charge; wherein the length-to-diameter ratio L / D of the central booster column is in the range of 0.8 to 1.

2.

8. The large-tonnage double-separation-surface cutting explosive bolt according to claim 6 is characterized in that: The detonating seat (18) comprises a T-shaped cylindrical structure and a boss; wherein: The boss is integrally connected to the upper surface of the T-shaped cylindrical structure; The cross section of the boss is an isosceles trapezoid; The upper surface of the detonating seat (18) is a contact surface with the shaped charge.

9. The large-tonnage double-separation-surface cutting explosive bolt according to claim 1, characterized in that: The materials of the first bolt body (2), the second bolt body (3) and the third bolt body (7) are all 0Cr13Ni8Mo2Al precipitation hardened stainless steel, and the hardness of the first bolt body (2), the second bolt body (3) and the third bolt body (7) is HRC40-45.

10. The large-tonnage double-separation-surface cutting explosive bolt according to claim 2, characterized in that: When the explosive bolt is working, the stress generated by the cutting ring is obtained by the following formula: σ1=P·r 2 / (R 2 -r 2 ); σ2=P·r 2 (R 2 +r 2 ) / [b 2 (R 2 -r 2 )]; σ3=-P; b = r + 0.5 × (R - r); Among them, σ1 is the axial stress, σ2 is the hoop stress, σ3 is the radial stress, P is the pressure generated by the electric initiator after operation, r is the inner diameter of the third bolt body, R is the outer diameter of the distribution circle of the weakest part of the third bolt body, and b is the median diameter.

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