Energy-gathering type preposed prefabricated fragment warhead structure

Abstract

The invention discloses an energy gathering type front prefabricated fragment warhead structure. The charging top end is designed to be the spherical segment cavity, the fragment box protruding outwards in a certain shape is filled with the prefabricated fragments, the lining is arranged at the spherical segment cavity, and through the material and structure matching design, the fragments cannot converge and collide in the radial direction in the driving process, deformation is small, and a better flight trajectory is achieved; and the two layers of gas closing structures restrain detonation products, so that leakage of the detonation products in gaps of the prefabricated fragments is greatly reduced, the energy utilization rate is increased, and the fragment power is increased.

Description

Technical Field

[0001] This invention relates to the field of warhead technology, and more specifically to a shaped charge warhead structure with pre-formed fragments. Background Technology

[0002] Pre-fragmented warheads utilize explosive detonation to drive pre-fragmented balls, such as steel or tungsten balls, loaded within their casing to damage personnel, lightly armored vehicles, and technical weapons. This type of warhead is the most widely used. Traditional pre-fragmented warheads disperse fragments uniformly in all directions, with most fragments failing to function. Therefore, directional fragmentation warheads, employing special structures to concentrate fragments and launch them in one direction, have been developed. The pre-embedded pre-fragmented warhead is a type of directional fragmentation warhead. Its pre-fragmented fragments are concentrated in the warhead's head, and explosive detonation drives the fragments along the warhead's axis, damaging targets within a circular sector. This damage field shape is particularly suitable for use with unmanned aerial vehicle (UAV) munitions and anti-UAV air defense munitions.

[0003] Currently, there are two main types of pre-fragmented warhead structures. One type arranges pre-fragmented fragments on the end face of a traditional cylindrical or protruding round-headed charge. Its advantage is its simple structure, but its disadvantages include low explosive energy utilization, low fragmentation velocity, and low yield. Inspired by shaped charge structures, designers have proposed a shaped charge pre-fragmented warhead structure. This structure involves creating a cavity at one end of the charge and filling it with pre-fragmented fragments. Utilizing the Munroe effect, it enhances axial energy output, significantly improving explosive energy utilization. With the same charge size, it achieves higher fragmentation velocity and greater yield.

[0004] The problems with the structure of shaped charge warheads with pre-formed fragments are as follows: First, the violent collision during fragment driving results in large fragment deformation, which affects the yield. Second, the design parameters of the initial velocity and dispersion angle of the fragments are coupled, resulting in low flexibility in the design of the fragment power field. Third, there is a lot of leakage of detonation products, resulting in low detonation energy utilization. Therefore, shaped charge warheads with pre-formed fragments are currently still in the theoretical research stage and are difficult to use in practice. Summary of the Invention

[0005] In view of this, the present invention provides an improved structure for a shaped charge warhead with pre-formed fragments, which solves the problems of large fragment deformation and excessive leakage of detonation products in existing shaped charge warheads, improves the energy utilization rate of explosives, and enhances the fragmentation power.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following solution: The shaped charge warhead structure of the present invention includes: a shell, a pressure screw, an upper cover, a lower cover, pre-fragmented components, an inner liner, a charge, a bottom cover, and a fuse; The outer shell has openings at both ends, and a bottom cover is installed at the bottom of the outer shell. The propellant is filled inside the outer shell, and the fuse passes through a pre-drilled hole on the bottom cover and contacts the bottom of the propellant. A spherical cavity is provided at the top of the propellant. The inner liner is attached to the spherical cavity. The lower cover and the upper cover form a convex fragment box, which is installed on the top of the outer shell. A screw is used to fix the inner liner, the lower cover, and the upper cover. Pre-made fragments are filled in the fragment box. The material density of the inner liner is greater than that of the lower cover.

[0007] Preferably, the radius of curvature R of the cavity in the charge sphere is... ZY =(100%~150%)D, where D is the diameter of the charge.

[0008] Preferably, the radius of curvature R of the fragment box G =(70%~90%)R ZY ;R ZY Let be the radius of curvature of the cavity in the explosive charge sphere.

[0009] Preferably, the lower cover is made of alloy steel, aluminum alloy, or titanium alloy, with a thickness H. XG =(3%~5%)D, and 4mm≤H XG ≤10mm, where D is the diameter of the charge.

[0010] Preferably, the inner lining is made of materials such as copper, alloy steel, aluminum alloy, and titanium alloy, with a thickness H. NC =(6%~7.5%)DH XG D is the diameter of the charge, H XG This refers to the thickness of the bottom cover.

[0011] Preferably, the top cover is made of nylon, polyethylene, or polytetrafluoroethylene, with a thickness of H. SG =(2%~5%)D, and 3mm≤H SG ≤10mm, where D is the diameter of the charge.

[0012] Preferably, the outer shell is made of 30CrMnSiNi2A steel, 22SiMn2TiB steel, or 28CrMo steel, with a wall thickness of H. WK =(8%~15%)D, where D is the diameter of the charge.

[0013] Preferably, the explosive charge is made by compression or injection using B explosive, 8701 explosive or JO-8 explosive, and the aspect ratio is not less than 0.8.

[0014] Preferably, the pre-formed fragments are arranged in 1 to 4 layers and are fixed by injecting epoxy resin, polyester resin or phenolic resin.

[0015] Preferably, the fragments are made of alloy steel, tungsten alloy, or energetic materials with good blast resistance, and have a diameter D. F=(2%~8%)D, and 4mm≤D F ≤15mm, where D is the diameter of the charge.

[0016] Beneficial effects: (1) Existing shaped charge warheads with pre-formed fragments drive the fragments in the cavity to converge toward the center and collide violently radially during the detonation of the shaped charge, resulting in large fragment deformation and a high fragmentation rate. The present invention replaces the existing shaped charge warheads with pre-formed fragments that are filled in the cavity of the shaped charge with fragments that are loaded in a fragment box that protrudes outward in a certain shape. The fragments will not converge and collide radially during the driving process, and the deformation is smaller, thus having a better flight trajectory and terminal power.

[0017] (2) The fragment arrangement structure of existing shaped charge warheads depends on the shaped charge structure. To increase fragment velocity, the radius of curvature of the shaped charge must be reduced, which will make the fragments disperse more densely and reduce the damage field, and vice versa. Therefore, the fragment kill field design is not flexible. This invention separates the fragment arrangement structure that controls the fragment dispersion range from the shaped charge structure that controls the fragment velocity. They can be adjusted separately within a certain range as needed, which improves the flexibility of warhead design.

[0018] (3) Existing shaped charge warheads with pre-formed fragments have no lining or only a very thin lining between the pre-formed fragments and the explosive charge. If the lining is too thick, it will enclose the fragments under the detonation drive of the explosive. A thinner lining is prone to rupture under the detonation, resulting in a large amount of leakage of detonation products from the gaps between the pre-formed fragments, which reduces the utilization rate of the explosive energy. The present invention adopts a two-layer gas-tight structure, which uses its material and structural matching design to constrain the detonation products during the fragment driving process, greatly reducing the leakage of detonation products between the gaps between the pre-formed fragments, improving the energy utilization rate, and increasing the fragment yield. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of the present invention.

[0020] Figure 2 This is a schematic diagram of the outer shell structure of the present invention.

[0021] Figure 3 This is a schematic diagram of the screw pressing structure of the present invention.

[0022] Figure 4 This is a schematic diagram of the upper cover structure of the present invention.

[0023] Figure 5 This is a schematic diagram of the lower cover structure of the present invention.

[0024] Figure 6 This is a schematic diagram of the pre-fragmented structure of the present invention.

[0025] Figure 7 This is a schematic diagram of the inner lining structure of the present invention.

[0026] Figure 8 This is a schematic diagram of the charge loading structure of the present invention.

[0027] Figure 9 This is a schematic diagram of the bottom cover structure of the present invention.

[0028] Figure 10 This is a schematic diagram of the fuse structure of the present invention.

[0029] Figure 11 Numerical simulation of fragment scattering during the operation of an embodiment of the present invention, wherein (a) is a side view; (b) is a top view.

[0030] Figure 12 Numerical simulation of fragment dispersion when a conventional shaped charge front-mounted fragmentation warhead of the same size as the embodiment of the present invention is used, wherein (a) is a side view; (b) is a top view.

[0031] Among them, 1-outer shell, 2-press screw, 3-upper cover, 4-lower cover, 5-pre-formed fragments, 6-inner liner, 7-charge, 8-bottom cover, 9-fuze. Detailed Implementation

[0032] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0033] This invention provides a structure for a shaped charge warhead with pre-formed fragments, such as... Figure 1 As shown, it includes an outer shell 1, a pressure screw 2, an upper cover 3, a lower cover 4, a pre-formed fragment 5, an inner liner 6, a charge 7, a bottom cover 8, and a fuse 9.

[0034] The outer shell 1 is a hollow cylinder of revolution, such as Figure 2 As shown, the outer shell 1 is open at both ends. One end has an internal thread or screw hole structure that mates with the bottom cover 8; the other end has a stepped groove for fixing the inner liner 6, the lower cover 4, and the upper cover 3, and the inner wall has threads that mate with the pressure screw 2; the middle section of the outer shell 1 is a hollow cylinder with a smooth inner wall that mates with the charge 7. The outer shell 1 is preferably made of 30CrMnSiNi2A steel, 22SiMn2TiB steel, 28CrMo steel, etc., with a yield strength of not less than 1300MPa; the wall thickness of the charge section outer shell is preferably H. WK =(8%~15%)D, where D is the diameter of charge 7.

[0035] The charge 7 is a cylindrical structure with a spherical cavity at one end, and its diameter is the same as the inner diameter of the middle section of the outer shell 1. Figure 8 As shown. The charge 7 is made using common explosives such as B explosive, 8701 explosive, and JO-8 through compression or injection, with a diameter of D and an aspect ratio of not less than 0.8. The radius of curvature of the spherical cavity of the charge 7 is preferably R.ZY =(100%~150%)D, which can utilize the focusing effect to concentrate the detonation energy of the explosive in the direction of the fragments, while preventing the detonation products in this direction from being too concentrated on the axis, resulting in uneven fragment dispersion.

[0036] The lower cover 4 and the upper cover 3 cooperate to form a fragment box with a certain internal space that protrudes outward, and are installed on the top of the outer shell 1. Specifically, the upper cover 3 is a rotating structure with one open end, and the side wall is cylindrical, which cooperates with the stepped groove of the outer shell 1. The top center is shaped like a spherical cap and protrudes outward. The diameter of the protruding part is the same as the diameter of the charge. Outside the protruding part is a circular plane, which is used to cooperate with the pressure screw 2 by clamping force. Figure 4 As shown. The lower cover 4 is an open-ended rotating structure that mates with the upper cover 3. Its sidewalls are cylindrical, with an outer diameter identical to the inner diameter of the upper cover 3. The bottom is a spherical cap that bulges inwards. Figure 5 As shown. The radius of curvature R of the protruding portions of the upper cover 3 and the lower cover 4. G Same, preferred R G =(70%~90%)R ZY A radius of curvature that is too small will result in sparse fragments at the center of the fragment dispersion field, and a large velocity difference between the center and the edge fragments; a radius of curvature that is too large will result in fragments being too concentrated, and may even be pushed towards the center by lateral detonation products, causing them to collide and deform. The height of the sidewalls of the upper cover 3 and the lower cover 4 is determined by the height of the fragment arrangement inside them.

[0037] The upper cover 3 is made of lightweight non-metallic materials such as nylon, polyethylene, and polytetrafluoroethylene, serving a sealing function and being fragile under explosion, allowing fragments to easily fly out; the preferred wall thickness of the protruding portion at the top of the upper cover 3 is H. SG =(2%~5%)D, but should not be less than 3mm or more than 10mm. If it is too thin, the fragments will be ejected from the fragment box too quickly, wasting detonation energy; if it is too thick, the fragments will have difficulty breaking through the upper cover 3, resulting in uneven dispersion. The lower cover 4 is made of metal materials such as alloy steel, aluminum alloy, and titanium alloy. In addition to encapsulating fragments, it also forms a gas-sealing layer when the charge 7 detonates to form a detonation wave, preventing premature fragment breakage. The wall thickness of the protruding part at the bottom of the lower cover 4 is preferably H. XG = (3%~5%)D, but should not be less than 4mm or more than 10mm. If it is too thin, the lower cover 4 will break prematurely during detonation, weakening the air-tightening effect. If it is too thick, the lower cover 4 will absorb too much detonation energy, affecting the fragment dispersion speed.

[0038] The inner liner 6 is a thin circular sheet with a spherical cap-shaped protrusion in the center that mates with the propellant charge, and a ring-shaped plane around its edge that mates with the stepped grooves of the outer shell. Figure 7As shown. The inner liner 6 is made of metal materials such as copper, alloy steel, aluminum alloy, and titanium alloy. The material density should be greater than that of the material used in the lower cover 4 so that stress waves are attenuated at the interface between the two materials. The thickness of the spherical protrusion of the inner liner 6 is preferably H. NC =(6%~7.5%)DH XG If it is too thick, it will hinder its overturning and deformation, and will consume detonation energy, reducing the fragment velocity; if it is too thin, it may break under the impact of detonation, and will not be able to play the role of air sealing and buffering.

[0039] The pre-formed fragments 5 are filled into a fragment box composed of the upper cover 3 and the lower cover 4, arranged in single or multiple layers, and fixed by injecting grouting materials such as epoxy resin, polyester resin, and phenolic resin. The number of fragment layers is generally 1 to 4. Due to the double-layer airtight protection of the inner liner 6 and the lower cover 4, the pre-formed fragments 5 can be designed into spherical, cylindrical, cubic, triangular prism, petal-cut columnar, or even needle-shaped or arrow-shaped shapes according to the target characteristics, thus broadening their applicability. The fragments are made of alloy steel, tungsten alloy, or other metallic materials, or can be made of energetic materials with good blast resistance. The pre-formed fragments 5 are preferably spherical, with a preferred diameter D. F =(2%~8%)D, if the fragments are too small, they will easily break into a large number of fragments under the impact of the detonation, and if the fragments are too large, the fragment density in the dispersion field will be too low, which is not conducive to exerting its power.

[0040] The pressure screw 2 is a rotating annular ring with threads on its outer side that mate with the outer shell 1. Its inner diameter is the same as the diameter of the charge 7. Figure 3 As shown. The pressure screw 2 is made of alloy steel or aluminum alloy, and its height is preferably 5~15mm.

[0041] The bottom cover 8 is a stepped disc with a central hole. Its outer diameter is the same as that of the outer shell. One end is flat, and the other end is a stepped disc that engages with the outer shell 1 via threads or bolts. A central hole mates with the fuse 9. The bottom cover 8 is made of 30CrMnSiNi2A steel, 22SiMn2TiB steel, 28CrMo steel, etc., with a yield strength of not less than 1300MPa and a preferred thickness of H. DG =(15%~20%)D.

[0042] The fuse 9 is cylindrical, with the same dimensions as the central hole of the bottom cover 8, and is connected to the bottom cover 8 by threads or bolts. The fuse 9 is a time-delay or proximity fuse.

[0043] When the warhead engages, the explosive charge 7 is detonated by the fuse 9. The detonation products move towards the inner liner 6 under the constraint of the bottom cover 8 and the outer shell 1. Driven by the detonation, the inner liner 6 flips and deforms forward, colliding with the lower cover 4. The inner liner 6 then adheres to the lower cover 4, forming a sealed structure that prevents the detonation products from leaking forward. Propelled by the detonation products, it drives the pre-fragmented fragments 5 forward. Simultaneously, the shock wave generated by the detonation products passes through the inner liner 6 and is transmitted to the lower cover 4. Because the inner liner 6 has a higher material density than the lower cover 4, the shock wave intensity is weakened, thus protecting the pre-fragmented fragments 5. Driven forward by the inner liner 6 and the lower cover 4, the pre-fragmented fragments 5 break through the upper cover 3 and fly out along the warhead axis, forming a circular fragmentation kill field. Due to the cavity structure of the charge 7, the axial velocity of the pre-fragmented fragments 5 decreases from the center of the warhead axis to the edge. Due to the protruding shape of the lower cover 4, the pre-fragmented fragments 5 all have a radial velocity away from the axis. The radial velocity decreases along the axis to the edge. Therefore, the fragments will not collide with each other along the axis, ensuring that the deformation of the pre-fragmented fragments 5 is small.

[0044] The following example illustrates this point: The shaped charge warhead structure of this embodiment includes: outer shell 1, pressure screw 2, upper cover 3, lower cover 4, pre-fragmented fragments 5, inner liner 6, explosive charge 7, bottom cover 8, and fuse 9.

[0045] The outer shell 1 is made of 30CrMnSiNi2A steel (density 7.85g / cm³). 3 It is made of material with an outer diameter of 180mm, an inner diameter of 150mm for the charge section, a wall thickness of 15mm, and an inner diameter of 166mm for the stepped groove section.

[0046] Among them, the pressure screw 2 is made of 30CrMnSiA steel (density 7.85g / cm³). 3 It is made of material with an outer diameter of 166mm, an inner diameter of 150mm, and a height of 8mm, and is connected to the outer shell 1 by threads.

[0047] The top cover 3 is made of nylon 66 (density 1.15 g / cm³). 3 It is made of a cylindrical part with a wall thickness of 5mm, a radius of curvature of 200mm, an outer diameter of 166mm, an inner diameter of 158mm, and a depth of 13mm.

[0048] The lower cover 4 is made of aluminum alloy (density 2.75g / cm³). 3 It is made of spherical notch with a wall thickness of 5mm, cylindrical sidewall with an outer diameter of 158mm, an inner diameter of 150mm, and a depth of 8mm.

[0049] Among them, the pre-fragmented fragment 5 is made of 30CrMnSiNi2A steel (density 7.85g / cm³). 3 Made of 8mm in diameter, arranged in a single layer inside the fragment box composed of upper cover 3 and lower cover 4.

[0050] Among them, the inner lining 6 is made of 30CrMnSiA steel (density 7.85g / cm³). 3 It is made of ) and has a thickness of 4mm.

[0051] Among them, charge 7 is made of 8701 explosive, with a diameter of 150mm, a length of 180mm, and a spherical cavity curvature radius of 200mm.

[0052] The bottom cover 8 is made of 30CrMnSiNi2A steel (density 7.85g / cm³). 3 It is made of 180mm outer diameter and 25mm thickness, and is connected to the outer shell 1 by a 10mm high thread. The center hole diameter is 50mm.

[0053] Among them, the fuse 9 is a time-delay fuse with a diameter of 50mm and a height of 25mm, and is connected to the bottom cover 8 by threads.

[0054] In this embodiment, the simulation calculation results of the pre-fragment 5 fragment scattering are as follows: Figure 11 As shown, the initial velocity of the fragments in the center can reach up to 2742 m / s, while the initial velocity of the fragments at the edges is 2177 m / s. Moreover, the fragments are scattered evenly, which is beneficial to improving the damage efficiency.

[0055] Simulation results of fragment dispersion for traditional shaped charge warheads with pre-formed fragments arranged closely to the inner liner, which have the same structure as this embodiment, are as follows: Figure 12 As shown, the initial velocity of the fragments in the center can reach up to 2568 m / s, while the initial velocity of the fragments at the edge is 2094 m / s. The initial velocity of the fragments is lower than that in this embodiment. Furthermore, the fragments disperse rapidly to the surrounding area after colliding with the axis during the driving process, resulting in sparse fragments in the central area and overly concentrated fragments at the edge, which is not conducive to improving the damage effectiveness.

[0056] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A structure for a shaped charge warhead with pre-formed fragments, characterized in that, include: Outer shell (1), screw (2), upper cover (3), lower cover (4), pre-fragmented fragments (5), inner liner (6), charge (7), bottom cover (8) and fuse (9); The outer shell (1) has openings at both ends, the bottom cover (8) is installed at the bottom of the outer shell (1), the charge (7) is filled inside the outer shell (1), and the fuse (9) passes through the pre-reserved through hole on the bottom cover (8) and contacts the bottom of the charge (7); the top of the charge (7) is provided with a spherical cavity; the inner liner (6) is attached to the spherical cavity; the lower cover (4) and the upper cover (3) form an outwardly protruding fragment box, which is installed on the top of the outer shell (1); the pressure screw (2) is used to fix the inner liner (6), the lower cover (4) and the upper cover (3); the pre-made fragments (5) are filled in the fragment box; the material density of the inner liner (6) is greater than that of the lower cover (4).

2. The warhead structure as described in claim 1, characterized in that, The radius of curvature R of the spherical cavity of the charge (7) ZY =(100%~150%)D, where D is the diameter of the charge (7).

3. The warhead structure as described in claim 1 or 2, characterized in that, The radius of curvature R of the fragment box G =(70%~90%)R ZY ;R ZY The radius of curvature of the cavity in the sphere (7) for loading the explosive.

4. The warhead structure as described in claim 1, characterized in that, The lower cover (4) is made of alloy steel, aluminum alloy or titanium alloy, with a thickness H. XG =(3%~5%)D, and 4mm≤H XG ≤10mm, D is the diameter of the charge (7).

5. The warhead structure as described in claim 1 or 4, characterized in that, The inner lining (6) is made of copper, alloy steel, aluminum alloy or titanium alloy, with a thickness of H. NC =(6%~7.5%)DH XG D is the diameter of the charge (7), H XG The thickness of the lower cover (4) is given.

6. The warhead structure as described in claim 1, characterized in that, The top cover (3) is made of nylon, polyethylene or polytetrafluoroethylene, with a thickness of H. SG =(2%~5%)D, and 3mm≤H SG ≤10mm, D is the diameter of the charge (7).

7. The warhead structure as described in claim 1, characterized in that, The outer shell (1) is made of 30CrMnSiNi2A steel, 22SiMn2TiB steel or 28CrMo steel, with a wall thickness of H. WK =(8%~15%)D, where D is the diameter of the charge (7).

8. The warhead structure as described in claim 1, characterized in that, The charge (7) is made by pressing or injection using B explosive, 8701 explosive or JO-8 explosive, with an aspect ratio of not less than 0.

8.

9. The warhead structure as described in claim 1, characterized in that, The pre-made fragments (5) are arranged in 1 to 4 layers and are fixed by injecting epoxy resin, polyester resin or phenolic resin.

10. The warhead structure as described in claim 1 or 9, characterized in that, The pre-formed fragments (5) are made of alloy steel, tungsten alloy, or energetic materials with good explosion resistance, and have a diameter D. F =(2%~8%)D, and 4mm≤D F ≤15mm, D is the diameter of the charge (7).

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