Pressure relief device

Abstract

The utility model relates to a pressure relief device, belongs to the technical field of safety, and solves the problems that the mechanical property of a containing part is damaged due to pressure relief of an existing device for containing explosives, and the maintenance cost is high. The pressure relief device is arranged at a closing-up part of an explosive containing part, is communicated with the explosive containing part and a fuze, and comprises a shell assembly, a pressure relief hole, a bracket and a wafer assembly, the shell assembly comprises a shell outer layer assembly, a shell interlayer part and a shell inner layer part; the thermal expansion coefficient of the material of the shell interlayer component is greater than that of the material of the shell inner layer component; the pressure relief holes comprise a first pressure relief hole and a second pressure relief hole; the first pressure relief hole is formed in the side wall of the shell assembly, and the second pressure relief hole is formed in the bottom of the shell assembly. The pressure relief device is independently arranged, so that the original design strength of the explosive containing part is not damaged, the maintenance cost is reduced, and double pressure relief can be realized.

Description

Technical Field

[0001] The utility model relates to the technical field of safety, in particular to a pressure relief device. Background Art

[0002] Dangerous and explosive materials may be exposed to strong external stimuli such as fire, bullet / fragment impact, jet, and detonation during transportation, storage, and in complex battlefield environments, which can easily lead to their own ignition and explosion, thus developing into accidents such as chain explosions in ammunition depots and explosion damage to ships / armored vehicles. Solving the insensitivity of ammunition under typical stimuli is of great significance to the safety and combat effectiveness of combat troops.

[0003] Devices that contain explosive items need to withstand extremely high pressure. The current pressure relief technology mainly involves opening holes or adding stress grooves on the shell of the container for explosive items. The current shell material is high-strength steel with a high fragmentation rate. Directly opening holes on the shell will damage the mechanical properties of the shell itself and may even affect the performance of the container for explosive items. In addition, the structure and material performance tests of the pressure relief holes of the container shell are routinely carried out, and the maintenance and repair costs are high. Utility Model Content

[0004] In view of the above analysis, the embodiment of the utility model aims to provide a pressure relief device to solve the problem that the pressure relief of the existing device for containing explosive items damages the mechanical properties of the containing part of the explosive items and has high maintenance costs.

[0005] The purpose of this utility model is mainly achieved through the following technical solutions:

[0006] A pressure relief device comprises a housing assembly, a pressure relief hole, a bracket and a cover plate assembly;

[0007] The shell assembly comprises a shell outer layer component, a shell sandwich component and a shell inner layer component; the thermal expansion coefficient of the material of the shell sandwich component is greater than the thermal expansion coefficient of the material of the shell inner layer component; the upper part of the shell inner layer component is provided with an internal thread, and the internal thread is used to connect the accommodating part of the explosive article; the lower part of the shell inner layer component is provided with an external thread, and the external thread is used to connect the fuse;

[0008] The pressure relief hole comprises a first pressure relief hole and a second pressure relief hole; the first pressure relief hole is arranged on the side wall of the shell component, and the second pressure relief hole is arranged on the bottom of the shell component;

[0009] The bracket is arranged inside or outside the second pressure relief hole, and the cover plate assembly covers the second pressure relief hole.

[0010] Furthermore, the bracket is fixed outside the second pressure relief hole.

[0011] Further, the cover plate assembly is hinged to the bracket, and the cover plate assembly can rotate around the hinge.

[0012] Further, the bracket is made of a metal material, and the cover plate assembly is made of a magnetic material.

[0013] Further, the bracket is fixed inside the second pressure relief hole.

[0014] Further, a spring is arranged on the bracket, and the other end of the spring is connected to the cover plate assembly.

[0015] Further, the first pressure relief hole is a through hole that is circumferentially distributed on the side wall of the housing assembly with the axis of the housing as the center.

[0016] Further, the inside of the first pressure relief hole is filled with a fusible material.

[0017] Further, a sealing layer is arranged outside the fusible material.

[0018] Further, the fusible material is polycarbonate.

[0019] Compared with the prior art, the present utility model can at least achieve one of the following beneficial effects:

[0020] (1) Compared with the prior art in which a pressure relief structure is formed by drilling holes or slots in the outer shell of the accommodating part of explosive articles, the present utility model separately provides a pressure relief device outside the accommodating part of explosive articles, and the pressure relief device is communicated with the accommodating part of explosive articles. On the one hand, the original design strength of the accommodating part of explosive articles is not damaged. On the other hand, the gas pressure generated by the charge in the accommodating part of explosive articles at high temperature can be directly transmitted to the pressure relief device, and the pressure is relieved through the pressure relief hole of the housing. The pressure relief device is arranged at the necking part of the accommodating part of explosive articles with relatively weak bearing capacity, which is easy to quickly relieve the pressure and reduces the danger of disaster caused by the explosion of the charge in the accommodating part of explosive articles.

[0021] (2) Compared with the prior art, the pressure relief device of the present utility model is composed of an outer layer component of the housing, an intermediate layer component of the housing, and an inner layer component of the housing. The difference in the thermal expansion coefficients of the materials of the intermediate layer component of the housing and the inner layer component of the housing is relatively large, which can cause the two materials to accelerate the thread destruction due to different deformation sizes at high temperature to quickly relieve the pressure and ensure the safety of the charge inside the accommodating part of explosive articles.

[0022] (3) Compared with the prior art, the utility model realizes double pressure relief by setting the second pressure relief hole, the bracket and the cover plate assembly, avoiding pressure relief failure caused by changes in the physical and chemical properties of materials during storage, transportation, etc. of a certain component. Since the bracket and the cover plate assembly are attracted by magnetic force and connected by a hinge, they can automatically reset after pressure relief, enabling unidirectional flow of internal gas, thereby enhancing the insensitive characteristics of the accommodating part for explosive articles.

[0023] (4) The second pressure relief hole in the utility model plays a role in pressure relief when the internal pressure of the device for accommodating explosive articles is relatively high and pressure relief is required; when the internal gas in the accommodating part of the explosive articles is relatively small and the pressure is relatively low, the cover plate assembly fits tightly with the bracket and the second pressure relief hole, sealing the inside of the accommodating part of the explosive articles, preventing the internal charge from coming into direct contact with the flame, and playing a role in moisture-proof sealing during storage and transportation.

[0024] (5) The utility model sets a spring between the bracket and the cover plate assembly, and uses the elastic force of the spring to realize the opening and automatic closing of the cover plate assembly. After pressure relief, it can automatically reset, enabling unidirectional flow of internal gas and enhancing the insensitive characteristics of the accommodating part for explosive articles.

[0025] (6) The utility model fills the first pressure relief hole with fusible material, which can form a pressure relief channel in case of accidents such as high temperature and fire, reduce the combustion growth rate after ignition of the internal charge in the accommodating part of the explosive articles, effectively control the development of the internal charge in the accommodating part of the explosive articles towards higher-level reactions such as explosion and detonation, thereby reducing or preventing the occurrence of disastrous accidents.

[0026] (7) Compared with the prior art, the pressure relief device in the utility model is independently arranged relative to the accommodating part for explosive articles and the fuse, which can significantly improve the maintenance convenience of insensitive ammunition. During inspection and maintenance, if a component is damaged, only the pressure relief device needs to be replaced or repaired, without the need to modify the accommodating part for explosive articles itself, reducing the maintenance cost.

[0027] In the utility model, the above technical solutions can also be combined with each other to achieve more preferred combination schemes. Other features and advantages of the utility model will be described in the following content, and some advantages can be made obvious from the description or understood by implementing the utility model. The purpose and other advantages of the utility model can be realized and obtained through the content specifically pointed out in the text and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The drawings are only for the purpose of showing specific embodiments and are not considered as a limitation to the utility model. Throughout the drawings, the same reference signs represent the same components.

[0029] Figure 1This is a schematic structural diagram of the first pressure relief hole in specific embodiment 1;

[0030] Figure 2 It is a schematic structural diagram of the second pressure relief hole of specific embodiment 1;

[0031] Figure 3 is a cross-sectional schematic diagram of a pressure relief device of specific embodiment 1;

[0032] Figure 4 It is a cross-sectional schematic diagram of the pressure relief device of specific embodiment 2.

[0033] Reference numerals:

[0034] 1-shell assembly, 101-shell outer layer component, 102-shell sandwich component, 103-shell inner layer component, 1031-internal thread, 1032-external thread, 2-pressure relief hole, 201-first pressure relief hole, 2011-fusible material, 2012-sealing layer, 202-second pressure relief hole, 3-bracket, 4-cover plate assembly, 5-spring. DETAILED DESCRIPTION

[0035] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings, wherein the accompanying drawings constitute a part of the present invention and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not used to limit the scope of the present invention.

[0036] When the container for explosive items is subjected to abnormal environmental stimulation, such as fire, the internal charge will decompose and produce a large amount of gas. In order to prevent the explosive charge from exploding or even detonating due to excessive internal air pressure, the internal gas of the container for explosive items needs to be discharged in time.

[0037] Example 1

[0038] This embodiment provides a pressure relief device, which is installed between the container of the explosive article and the fuse, and is connected with the container of the explosive article and the fuse. The pressure relief device includes a housing component 1, a pressure relief hole 2, a bracket 3 and a cover plate component 4.

[0039] In order to facilitate pressure relief of the device for containing explosive items, the pressure relief device is arranged at the closing part of the containing part of the explosive items with weak bearing capacity. The upper part of the shell assembly 1 is provided with an internal thread 1031 for connecting with the closing part of the shell of the containing part of the explosive items; the lower part is provided with an external thread 1032 for connecting with the fuse.

[0040] Compared with the prior art, in which a pressure relief structure is formed by punching holes or slotting on the shell of the container of the explosive article, in this embodiment, an additional pressure relief device is arranged between the container of the explosive article and the fuse, and the pressure relief device is connected to the container of the explosive article. On the one hand, the original design strength of the container of the explosive article is not destroyed, and on the other hand, the gas pressure generated by the explosive article container at high temperature can be directly transmitted to the pressure relief device, and the pressure is relieved through the pressure relief hole 2 of the shell. The pressure relief device is arranged at the closing part of the container of the explosive article with weak bearing capacity, which is easy to quickly achieve pressure relief, reducing the risk of disaster caused by the explosion of the explosive article container.

[0041] The shell assembly 1 includes a shell outer layer component 101, a shell sandwich component 102 and a shell inner layer component 103. In order to avoid the problem of flight air resistance of the device containing explosive items due to the installation of a pressure relief device, the shell outer layer component 101 matches the outer curve of the container for explosive items, and the shell outer layer component 101 is made of the same high-strength steel as the outer shell of the container for explosive items.

[0042] In order to achieve pressure relief as soon as possible at high temperatures, the shell sandwich component 102 and the shell inner component 103 are made of materials with different thermal expansion coefficients. The shell sandwich component 102 is made of a temperature-sensitive alloy with a large thermal expansion coefficient; the shell inner component 103 with threads at both ends is made of a fusible alloy with a low thermal expansion coefficient, medium strength and a low melting point. The thermal expansion coefficients of the shell sandwich component 102 and the shell inner component 103 are quite different, which can accelerate the destruction of the threads of the two materials under high temperature to achieve pressure relief as soon as possible.

[0043] Compared with the prior art, the pressure relief device of this embodiment is composed of an outer shell component 101, a shell sandwich component 102 and a shell inner layer component 103. The thermal expansion coefficients of the materials of the shell sandwich component 102 and the shell inner layer component 103 are quite different, which can accelerate the destruction of the threads due to the different deformation sizes of the two materials under high temperature conditions, so as to achieve pressure relief as soon as possible and ensure the safety of the explosive charge inside the accommodating part of the explosive items.

[0044] When the device for accommodating explosive items releases pressure, the pressure is released through the pressure relief hole 2. The pressure relief hole 2 includes a first pressure relief hole 201. The first pressure relief hole 201 is a plurality of through holes arranged on the side wall of the pressure relief device housing assembly 1. Specifically, in order to make the load of the device for accommodating explosive items uniform, the through holes have equal diameters and are evenly distributed on the side wall of the housing along the circumferential direction.

[0045] When pressure relief is required in a high-temperature environment, a material that is easy to melt is filled inside the first pressure relief hole 201 so that a pressure relief channel is automatically formed inside the device for accommodating explosive items. In this embodiment, polycarbonate is used. As an alternative to this embodiment, other fusible materials 2011 can also be used. The outside of the fusible material 2011 is sealed with a sealing layer 2012 made of the same material as the outer layer component 101 of the housing to prevent the fusible material 2011 from coming into direct contact with air, which may cause changes in its physical and chemical properties. Specifically, the thickness of the outer sealing layer 2012 is 10 μm - 1 mm. The melting point of polycarbonate is 220 °C. When the temperature is higher than 220 °C, the polycarbonate inside the first pressure relief hole 201 melts to form a pressure relief channel. Under the action of strong pressure, the gas directly acts on the outer sealing layer 2012, cracking the outer sealing layer 2012 and discharging through the first pressure relief hole 201 to achieve pressure relief.

[0046] In this embodiment, a fusible material 2011 is filled in the first pressure relief hole 201, which can form a pressure relief channel in case of accidents such as high temperature and fire, reduce the combustion growth rate after the charge inside the accommodating part of the explosive item is ignited, and effectively control the development of the charge in the accommodating part of the explosive item towards higher-level reactions such as explosion and detonation, thereby reducing or eliminating the occurrence of disastrous accidents.

[0047] Furthermore, to prevent the first pressure relief hole 201 from failing to relieve pressure during storage and transportation, a second pressure relief hole 202 is also provided. The second pressure relief hole 202 is a through hole provided at the bottom of the housing. In this embodiment, the second pressure relief hole 202 includes a central circular hole at the center of the bottom of the housing and circular holes evenly distributed around the central circular hole along the circumferential direction. It should be noted that in order to relieve pressure quickly, the diameter of the central circular hole is set larger than the diameter of the circular holes distributed in the circumference.

[0048] A bracket 3 is provided at the orifice of the second pressure relief hole 202. The bracket 3 is made of circular ring-shaped metal and is fixed to the outer surface of the housing, and the fixing method is welding or riveting.

[0049] The cover plate assembly 4 is made of magnetic material and covers the second pressure relief hole 202 from the outside of the housing. The cover plate assembly 4 includes a central circular plate covering the central through hole and small circular plates covering several small circular holes. The cover plate assembly 4 is hingedly connected to the bracket 3. In this embodiment, the hinge connection between the cover plate assembly 4 and the bracket 3 is set to be connected by a hinge. Specifically, the hinge covers one-eighth of the circumference of the circular plate, and the cover plate assembly 4 can rotate 90° around the hinge.

[0050] During the normal transportation and storage of the accommodating part for explosive articles, the cover plate assembly 4 and the bracket 3 are tightly combined under the action of magnetic force. When encountering abnormal environmental stimuli, the internal charge of the accommodating part for explosive articles decomposes, generating a large amount of gas. The cover plate assembly 4 is pushed open under the gas pressure, rotates around the hinge, and the gas is discharged through the second pressure relief hole 202 exposed by the cover plate assembly 4 to achieve pressure relief. After the pressure relief is completed, the disc fits back onto the bracket 3 under the action of magnetic force.

[0051] Compared with the prior art, in this embodiment, by providing the second pressure relief hole 202, the bracket 3, and the cover plate assembly 4, double pressure relief is achieved, avoiding pressure relief failure caused by changes in the physical and chemical properties of materials during storage and transportation and other processes. Since the bracket 3 and the cover plate assembly 4 are attracted and hinged by magnetic force, automatic reset can be achieved after pressure relief, enabling unidirectional flow of the internal gas, thereby enhancing the insensitive characteristics of the accommodating part for explosive articles.

[0052] The second pressure relief hole 202 in this embodiment plays a role in pressure relief when the internal pressure of the device for accommodating explosive articles is relatively large and pressure relief is required; when the internal gas of the accommodating part for explosive articles is less and the pressure is relatively small, the cover plate assembly 4 fits tightly with the bracket 3, sealing the inside of the accommodating part for explosive articles to prevent the internal charge from coming into direct contact with the flame, and playing a role in moisture-proof sealing during storage and transportation.

[0053] The working process of this embodiment is as follows:

[0054] Under the action of high temperature, the fusible material 2011 filled in the first pressure relief hole 201 melts. Under the strong pressure of the internal gas, the gas directly acts on the external sealing layer 2012, cracking the external sealing layer 2012, and is discharged through the first pressure relief hole 201 to start pressure relief;

[0055] The inner fusible alloy reaches the melting point, the material becomes soft, and the strength of the fusible alloy thread reaches the limit;

[0056] Under the strong gas pressure inside the accommodating part for explosive articles, the cover plate assembly 4 is pushed open, and the second pressure relief hole 202 starts to relieve pressure;

[0057] When the gas pressure is relatively large, due to the large difference in the thermal expansion coefficients of the materials of the housing sandwich component 102 and the inner housing component 103, displacement occurs at the fusible alloy thread, the fusible alloy thread is sheared and damaged, the fuse is ejected by the gas, and at the same time, the alloy with a high thermal expansion coefficient in the housing sandwich of the pressure relief device deforms at high temperature, and displacement occurs in the normal direction of the port interface of the accommodating part for explosive articles, causing the fuse to break free from the thread.

[0058] Compared with the prior art, the pressure relief device in this embodiment can significantly improve the maintenance convenience of insensitive ammunition. During inspection and repair, if a component is damaged, only the pressure relief device needs to be replaced or repaired, without modifying the accommodating part of the explosive itself, reducing the maintenance cost.

[0059] Embodiment 2

[0060] In Embodiment 1, the cover plate assembly 4 and the bracket 3 are fixed by magnetic attraction. When the gas pressure is relatively high, the gas blows open the cover plate assembly 4, and the disc rotates around the hinge. After the gas is discharged, the disc automatically covers the second pressure relief port under the action of magnetic force, sealing the internal charge of the device for accommodating the explosive.

[0061] In this embodiment, the bracket 3 of Embodiment 1 is arranged inside the second pressure relief port, and a plurality of springs 5 are uniformly arranged on the bracket 3. The other end of the spring 5 is connected to the disc.

[0062] During the transportation of the accommodating part of the explosive, the disc seals the second pressure relief port. At this time, the spring 5 is in an extended state. The elastic force of the spring 5 tightly pulls the disc, making the disc closely adhere to the outside of the second pressure relief port.

[0063] When pressure relief is required, the internal gas impact force is greater than the elastic force of the spring 5, and the disc is blown open to achieve pressure relief.

[0064] After pressure relief, the internal gas pressure is weak, less than the elastic force of the spring 5, and the spring 5 tightly pulls the disc again, closely adhering to the outside of the second pressure relief port to seal the internal charge.

[0065] In this embodiment, a spring 5 is arranged between the bracket 3 and the cover plate assembly 4, and the opening and automatic closing of the cover plate assembly 4 are realized by using the elastic force of the spring 5. After pressure relief, automatic reset can be achieved, enabling the internal gas to flow unidirectionally, and improving the insensitive characteristics of the accommodating part of the explosive.

[0066] The above is only the preferred specific embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present utility model should be covered within the protection scope of the present utility model.

Claims

1. A pressure relief device, characterized in that: It comprises a housing assembly (1), a pressure relief hole (2), a bracket (3) and a cover assembly (4); The shell assembly (1) comprises a shell outer layer component (101), a shell sandwich component (102) and a shell inner layer component (103); the thermal expansion coefficient of the material of the shell sandwich component (102) is greater than the thermal expansion coefficient of the material of the shell inner layer component (103); the upper part of the shell inner layer component (103) is provided with an internal thread (1031), and the internal thread (1031) is used to connect to a accommodating part of explosive items; the lower part of the shell inner layer component (103) is provided with an external thread (1032), and the external thread (1032) is used to connect to a fuse; The pressure relief hole (2) comprises a first pressure relief hole (201) and a second pressure relief hole (202); the first pressure relief hole (201) is arranged on the side wall of the shell component (1), and the second pressure relief hole (202) is arranged on the bottom of the shell component (1); The bracket (3) is arranged inside or outside the second pressure relief hole (202), and the cover plate assembly (4) covers the second pressure relief hole (202).

2. The pressure relief device according to claim 1, characterized in that: The bracket (3) is fixed outside the second pressure relief hole (202).

3. The pressure relief device according to claim 2, characterized in that: The cover plate assembly (4) is hinged to the bracket (3), and the cover plate assembly (4) is capable of rotating around the hinge.

4. The pressure relief device according to claim 3, characterized in that: The cover plate assembly (4) is made of magnetic material.

5. The pressure relief device according to claim 1, characterized in that: The bracket (3) is fixed inside the second pressure relief hole (202).

6. The pressure relief device according to claim 5, characterized in that: The bracket (3) is provided with a spring (5), and the other end of the spring (5) is connected to the cover plate assembly (4).

7. The pressure relief device according to claim 1, characterized in that: The first pressure relief hole (201) is a through hole centered on the axis of the housing assembly (1) and distributed in a circular pattern on the side wall of the housing assembly (1).

8. The pressure relief device according to claim 7, characterized in that: The first pressure relief hole (201) is filled with fusible material (2011).

9. The pressure relief device according to claim 8, characterized in that: A sealing layer (2012) is provided outside the fusible material (2011).

10. The pressure relief device according to claim 8, characterized in that: The fusible material (2011) is polycarbonate.

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