Explosion-proof device and power transmission line

Abstract

The application relates to an explosion-proof device and a power transmission line, comprising a sleeve and a framework, the sleeve is used for sleeving a cable joint, the framework comprises a shape memory body, the shape memory body is arranged in the sleeve, and when the temperature of the shape memory body is greater than a preset temperature, the shape memory body can generate a restoring force to enable the sleeve to restore to the original state after deformation. Compared with the prior art, the explosion-proof device utilizes the restoring force generated by the shape memory body under heat to offset the high-pressure impact on the inside of the sleeve caused by explosion, enhances the bearing capacity of the sleeve to the pressure impact, avoids explosion failure of the explosion-proof device, and effectively improves the safety of power grid operation and on-site operators.

Description

Technical Field

[0001] This application relates to the technical field of power engineering, and in particular to an explosion-proof device and a transmission line. Background Technology

[0002] As a core component connecting two sections of cable and ensuring continuous power transmission, cable joints are prone to insulation breakdown and short circuit faults due to insulation aging, installation defects, partial discharge, etc. during long-term operation. This can release a large amount of arc energy in a short period of time, which can then lead to an explosion.

[0003] To reduce the hazards of explosions, cable joints are generally equipped with explosion-proof devices. Traditional explosion-proof devices are mostly made of ordinary steel, ceramics and other materials. Because the explosion of a cable joint will generate huge internal pressure in the explosion-proof device, the traditional explosion-proof device is difficult to withstand the impact of the instantaneous pressure under high temperature conditions, and is prone to overall rupture. The fragments after the rupture will cause secondary damage to surrounding cables, equipment and other equipment, seriously threatening the safety of the power grid and the safety of on-site personnel. Summary of the Invention

[0004] Therefore, it is necessary to provide an explosion-proof device and transmission line to address the problem that traditional explosion-proof devices may burst due to the impact of an explosion, threatening the safety of the power grid and on-site personnel.

[0005] The technical solution is as follows:

[0006] One embodiment provides an explosion-proof device, comprising:

[0007] A sleeve, which is used to cover the outside of a cable joint;

[0008] A skeleton, the skeleton including a shape memory, the shape memory being disposed in the envelope;

[0009] When the temperature of the shape memory is higher than a preset temperature, the shape memory can generate a restoring force so that the deformed cover can return to its original shape.

[0010] The aforementioned explosion-proof device surrounds the cable joint with a sheath, providing comprehensive protection. When the cable joint explodes, a large amount of heat and high-pressure impact are generated inside the sheath. This heat is transferred to the shape memory element, causing its temperature to exceed a preset level. The restoring force generated by the shape memory element then counteracts the high-pressure impact of the explosion, allowing the sheath to return to its original shape after the explosion. Compared to traditional technologies, this explosion-proof device utilizes the restoring force generated by the heated shape memory element to counteract the high-pressure impact of the explosion, enhancing the sheath's resistance to pressure shocks and preventing the explosion-proof device from bursting and failing. This effectively improves the safety of power grid operation and on-site personnel.

[0011] In one embodiment, the shape memory is ring-shaped and arranged around the axial direction of the envelope.

[0012] In one embodiment, at least two shape memory cells are provided, and the at least two shape memory cells are spaced apart along the axial direction of the envelope.

[0013] In one embodiment, the skeleton further includes a reinforcement that extends axially along the envelope and intersects at least one of the shape memory elements.

[0014] In one embodiment, the reinforcement is provided in at least two parts, and the at least two reinforcements are arranged at circumferential intervals along the cover.

[0015] In one embodiment, the envelope includes an explosion-proof layer and a thermally conductive layer, the explosion-proof layer being sleeved outside the thermally conductive layer, and the skeleton being disposed inside the explosion-proof layer.

[0016] In one embodiment, the thermally conductive layer includes a fireproof felt and a thermally conductive filler, the fireproof felt having a first pore and the thermally conductive filler filling the first pore.

[0017] In one embodiment, the explosion-proof layer includes castable filler that wraps around the skeleton and at least a portion of the castable filler fills the first pores.

[0018] In one embodiment, the skeleton has a second pore, and at least a portion of the casting filler is filled within the second pore.

[0019] Another embodiment provides a power transmission line including a first cable, a second cable, a cable joint, and an explosion-proof device as described above, wherein the first cable is connected to the second cable through the cable joint, and the sheath is fitted over the cable joint.

[0020] The aforementioned transmission line uses an enclosure to protect the cable joint. When the cable joint explodes, a large amount of heat and high-pressure impact are generated inside the enclosure. This heat is transferred to the shape memory element, causing its temperature to exceed a preset temperature. The restoring force generated by the shape memory element then counteracts the high-pressure impact of the explosion, allowing the enclosure to return to its original shape after the explosion. Compared to traditional technologies, this transmission line utilizes the restoring force generated by the heated shape memory element to counteract the high-pressure impact of the explosion on the enclosure, enhancing its resistance to pressure shocks and preventing the explosion-proof device from rupturing and failing. This effectively improves the safety of power grid operation and on-site personnel. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the structure of the envelope in one embodiment of this application.

[0023] Figure 2 This is a schematic diagram of the skeleton structure in one embodiment of this application.

[0024] Figure 3 This is a schematic diagram of the structure of the fireproof felt in one embodiment of this application.

[0025] Figure 4 This is a schematic diagram of the structure combining the explosion-proof layer and the heat-conducting layer in one embodiment of this application.

[0026] Attached image annotations:

[0027] 100. Enclosure; 110. Explosion-proof layer; 111. Casting filler; 120. Thermally conductive layer; 121. Fireproof felt; 122. Thermally conductive filler; 200. Skeleton; 210. Shape memory element; 220. Reinforcing body. Detailed Implementation

[0028] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0029] In the description of this application, it should be understood that if terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0030] Furthermore, where the terms "first" and "second" appear, these terms are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0031] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0032] In this application, unless otherwise expressly specified and limited, the use of descriptions such as "above" or "below" the second feature indicates that the first and second features are in direct contact or indirect contact via an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. Similarly, "below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0033] It should be noted that if an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. If so, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.

[0034] Please see Figure 1 and Figure 2One embodiment of this application provides an explosion-proof device, including a sleeve 100 and a frame 200. The sleeve 100 is used to cover the outside of a cable connector. The frame 200 includes a shape memory 210, which is disposed on the sleeve 100. When the temperature of the shape memory 210 is higher than a preset temperature, the shape memory 210 can generate a restoring force so that the sleeve 100 after deformation can return to its original shape.

[0035] The aforementioned explosion-proof device places the sleeve 100 over the cable joint, providing comprehensive protection. When the cable joint explodes, a large amount of heat and high-pressure impact are generated inside the sleeve 100. This heat is transferred to the shape memory element 210, causing its temperature to exceed a preset temperature. The restoring force generated by the shape memory element 210 then counteracts the high-pressure impact on the inside of the sleeve 100 caused by the cable joint explosion, allowing the sleeve 100 to return to its original shape after the explosion. Compared to traditional technologies, this explosion-proof device utilizes the restoring force generated by the heated shape memory element 210 to counteract the high-pressure impact on the inside of the sleeve 100, enhancing the sleeve 100's ability to withstand pressure shocks and preventing the explosion-proof device from rupturing and failing. This effectively improves the safety of power grid operation and on-site personnel.

[0036] Further, please refer to Figure 1 and Figure 2 The sheath 100 has a stepped structure that is narrow at both ends and wide in the middle to match the shape of the cable connector.

[0037] Furthermore, the envelope 100 has a cavity and a first opening and a second opening at both ends of the cavity. The first opening and the second opening are respectively used for two cables to pass through, and the two cables are connected in the cavity through a cable connector.

[0038] Optionally, the shape memory 210 can be disposed on the outer wall of the cover 100, or on the cavity wall of the cover 100, or inside the cover 100, as long as it can cause the cover 100 to deform. No specific limitation is made here.

[0039] Optionally, in some embodiments, the shape memory 210 is made of a shape memory material, including but not limited to shape memory alloys, shape memory polymers, shape memory ceramics, etc.

[0040] In one embodiment, the shape memory 210 is made of shape memory alloy (SMA), which has high recovery force, high mechanical strength, fast response speed and high temperature resistance, which can effectively improve the practicality of explosion-proof devices.

[0041] Furthermore, the shape memory alloy, which is the shape memory element 210, needs to have its chemical composition and heat treatment process precisely designed to ensure that the reversible phase transformation response temperature (i.e., the preset temperature) between its austenitic and martensitic phases is set in a range slightly below the critical explosion temperature of the cable joint. This allows the shape memory alloy to transform from the austenitic state to the martensitic structure when the temperature of the sheath 100 exceeds the preset temperature, and to generate high-intensity shrinkage recovery stress. After the explosion, it can restore its original shape, thereby enabling the sheath 100 to return to its original state.

[0042] Optionally, the shape memory alloy can be a copper-based shape memory alloy or an iron-based shape memory alloy, as long as its phase change response temperature is set slightly below the critical explosion temperature of the cable joint and it can achieve the corresponding shrinkage recovery and energy absorption functions. No specific limitation is made here.

[0043] For example, the phase transformation temperature range of shape memory alloys can be from 120°C to 160°C, and the explosion temperature range of cable joints can be from 250°C to 300°C.

[0044] Please see Figure 2 In one embodiment, the shape memory 210 is annular and arranged axially around the sleeve 100.

[0045] The annular shape memory 210 is arranged around the envelope 100 to achieve uniform support and force on the envelope 100; under the heat generated by the explosion of the cable joint, the annular shape memory 210 can be heated synchronously in the circumference, thereby generating a restoring force synchronously, so as to apply a uniform radial restoring force to the envelope 100, so that the envelope 100 can more quickly restore its original shape.

[0046] In one embodiment, the envelope 100 has a circular cross-section, and the shape memory 210 has an annular shape to match the cross-sectional shape of the envelope 100.

[0047] Please see Figure 2 In one embodiment, at least two shape memory cells 210 are provided, and the at least two shape memory cells 210 are spaced apart along the axial direction of the envelope 100.

[0048] The pressure impact generated by the cable joint explosion is unevenly distributed along the axial direction of the sleeve 100. At least two spaced shape memory elements 210 can synchronously generate restoring force in different regions along the axial direction of the sleeve, which can more comprehensively offset the explosion impact, make the sleeve 100 more uniformly stressed, and thus make the sleeve 100 more stable and reliable in restoring its original shape after the cable joint explosion.

[0049] Further, please refer to Figure 2At least two annular shape memory elements 210 are arranged parallel to and spaced apart along the axial direction of the sleeve 100 to uniformly apply radial restoring force to different areas along the axial direction of the sleeve 100, making the sleeve 100 more stable and reliable in restoring its original shape after the cable joint explodes.

[0050] Please see Figure 2 In one embodiment, the skeleton 200 further includes a reinforcement 220 that extends along the axial direction of the envelope 100 and intersects with at least one shape memory 210.

[0051] The reinforcing body 220 extending axially along the envelope 100 can form a cross-reinforcing structure with at least one shape memory rubber 210, thereby improving the overall structural strength and impact resistance of the envelope 100. In addition, the reinforcing body 220 can also position the shape memory 210, preventing it from shifting, twisting, or even falling off during explosive impact or thermal deformation, ensuring that the shape memory 210 can always be in the predetermined position and apply a restoring force to that position.

[0052] Please see Figure 2 In one embodiment, at least two reinforcements 220 are provided, and the at least two reinforcements 220 are spaced apart circumferentially along the cover 100.

[0053] At least two reinforcing bodies 220 are distributed at intervals along the circumference of the envelope 100 to provide uniform support and reinforcement at different positions along the circumference of the envelope 100, preventing the envelope 100 from tearing or breaking due to the explosive impact of the cable joint; in addition, the at least two reinforcing bodies 220 can also limit and constrain the shape memory 210 at multiple positions, further preventing the shape memory 210 from shifting or twisting, and improving the reset effect of the envelope 100 after the explosion.

[0054] Further, please refer to Figure 2 Both the shape memory 210 and the reinforcement 220 are filamentous. The filamentous shape memory 210 is arranged around the axial direction of the sleeve 100, and the filamentous reinforcement 220 extends along the axial direction of the sleeve 100 to jointly form a spatial grid skeleton 200 on the sleeve 100. This disperses and transmits the impact force when the cable joint explodes, effectively reduces local stress concentration, reduces the risk of tearing or damage to the sleeve 100, and improves explosion-proof reliability.

[0055] Optionally, in some embodiments, the reinforcement 220 is made of high-performance inorganic fibers, such as basalt fiber, carbon fiber, silicon boron fiber, etc., as long as it has high heat resistance and high tensile strength, and can be formed into a high-modulus, high-toughness spatial grid skeleton 200 through three-dimensional weaving. No specific limitation is made here.

[0056] Further, please refer to Figure 2 The filamentous shape memory 210 is orthogonally woven in three dimensions under strict proportional control along the transverse direction and the filamentous reinforcement 220 along the longitudinal direction to form a high-strength, high-modulus spatial grid skeleton 200. During the weaving process, the diameter and spatial gap uniformity of the reinforcement 220 and the shape memory 210 need to be controlled to ensure the overall structural toughness and thermal management consistency of the skeleton 200.

[0057] Please see Figure 1 and Figure 4 In one embodiment, the cover 100 includes an explosion-proof layer 110 and a heat-conducting layer 120, with the explosion-proof layer 110 sleeved outside the heat-conducting layer 120 and the skeleton 200 disposed inside the explosion-proof layer 110.

[0058] The heat-conducting layer 120 can cover the cable joint. On the one hand, it can dissipate the heat generated during the operation of the cable joint in a timely manner when the cable joint is in normal use, so as to avoid the heat accumulation and overheating of the cable joint and accelerated aging. On the other hand, when the cable joint explodes, the heat-conducting layer 120 can quickly and evenly conduct the heat generated by the explosion to the shape memory 210 inside the explosion-proof layer 110, so that the shape memory 210 can quickly reach the preset temperature and generate the recovery force in time, thereby improving the response speed and protection timeliness of the explosion-proof device.

[0059] In addition, the outer explosion-proof layer 110 has high structural strength and impact resistance, which can not only effectively withstand the high-pressure impact generated by the explosion of the cable joint, but also prevent the impact of external objects on the explosion-proof device.

[0060] Please see Figure 3 In one embodiment, the thermally conductive layer 120 includes a fireproof felt 121 and a thermally conductive filler 122. The fireproof felt 121 has a first pore, and the thermally conductive filler 122 fills the first pore.

[0061] The fireproof felt 121 has good flexibility and conformability, so as to closely fit the surface of the cable joint and adapt to the wrapping requirements of cable joints of different specifications. At the same time, the fireproof felt 121 itself has fireproof and heat insulation effects, which can isolate external open flames and high temperature corrosion during normal operation of the cable joint to protect the cable joint. The first pore of the fireproof felt 121 provides a filling space for the heat-conducting filler 122. After the heat-conducting filler 122 fills the pores, it can form a heat conduction path to conduct the heat generated by the cable joint during normal operation, so as to avoid heat accumulation. It can also quickly and evenly transfer the high temperature generated by the cable joint explosion to the shape memory 210 in the explosion-proof layer 110, so that the shape memory 210 can quickly reach the preset temperature and ensure that the explosion-proof device can respond in a timely manner.

[0062] Optionally, the fireproof felt 121 can be made of silica aerogel felt, alumina aerogel felt or carbon aerogel felt, or other types of nanoporous thermal insulation materials, as long as they have low thermal conductivity, high specific surface area and first pores for filling the thermally conductive filler 122. No specific limitation is made here.

[0063] Furthermore, the first pore of the fireproof felt 121 is a number of nanopores on the fireproof felt 121.

[0064] Optionally, the thermally conductive filler 122 can be a high thermal conductivity ceramic filler such as boron nitride (BN) filler, alumina filler, or aluminum nitride filler that can meet the requirements of thermal conductivity and interfacial bonding. No specific limitation is made here.

[0065] Preferably, the fireproof felt 121 is made of silica aerogel felt, and the thermally conductive filler 122 is made of boron nitride filler. Before use, it needs to be dried in a vacuum environment to remove adsorbed water from the aerogel pad. The boron nitride filler is functionalized to successfully graft amino-rich molecular chains onto its edges and surface, significantly enhancing its hydrophilicity and surface activity, preparing for subsequent improvement of the thermal conductivity of the aerogel felt. A vacuum-assisted impregnation process is used to uniformly embed the modified boron nitride filler into the first pore of the aerogel felt. A boron nitride dispersion with a solid content of 10-15% is first prepared and ultrasonically treated to ensure uniform dispersion. Under vacuum conditions, multiple impregnation-vacuum cycles are used to disperse the boron nitride filler in the inorganic network structure with high density, uniformity, and stability. Finally, the aerogel felt is dried to achieve high overall uniform thermal conductivity of the thermally conductive layer 120 while maintaining ultra-low radial thermal conductivity.

[0066] Please see Figure 2 In one embodiment, the explosion-proof layer 110 includes a castable filler 111, which is wrapped around the skeleton 200 and at least a portion of the castable filler 111 fills the first pores.

[0067] The casting filler 111 is wrapped around the shape memory body 210 and the reinforcing body 220, and at least part of it penetrates into the first pores of the fireproof felt 121, so that the explosion-proof layer 110, the heat-conducting layer 120, the shape memory body 210 and the reinforcing body 220 form an integrated structure, avoiding misalignment or detachment between the layers and improving the overall structural strength and stability of the explosion-proof device; the casting filler 111 fills the first pores of the fireproof felt 121, which can effectively eliminate the interlayer gap between the explosion-proof layer 110 and the heat-conducting layer 120, thereby reducing the cross-sectional thermal resistance and allowing the heat of the heat-conducting layer 120 to be transferred to the explosion-proof layer 110 more quickly.

[0068] Optionally, the casting filler 111 can be epoxy resin casting material, polyurethane casting material or silicone casting material, as long as it can form a high-strength explosion-proof structure for the shape memory body 210 and the reinforcing body 220, and no specific limitation is made here.

[0069] In one embodiment, the skeleton 200 has a second pore, and at least a portion of the casting filler 111 fills the second pore.

[0070] At least a portion of the casting filler 111 fills the second pores of the skeleton 200, so that the skeleton 200 and the casting filler 111 form a mechanical interlock, making the skeleton 200 and the casting filler 111 more secure; the skeleton 200 and the casting filler 111 can jointly withstand the explosive impact, significantly improving the structural strength, toughness and tear resistance of the explosion-proof layer 110; in addition, it can also eliminate the thermal resistance caused by the internal voids of the skeleton 200, so that heat can be transferred smoothly.

[0071] In one embodiment, the reinforcing body 220 is made of basalt fiber bundles, the surface of which has second pores, and at least a portion of the casting filler 111 can fill the second pores to achieve a more robust connection with the reinforcing body 220.

[0072] Furthermore, the second pore is a nanopore on the surface of the reinforcement 220 made of basalt fiber bundles.

[0073] Preferably, the casting filler 111 is made of boron nitride modified epoxy resin.

[0074] Furthermore, the boron nitride modified epoxy resin used as the casting filler 111 needs to undergo surface functionalization modification to improve the thermal conductivity and cross-sectional bonding strength of the casting filler 111. Under vacuum conditions, the boron nitride-epoxy resin mixture is cast onto the skeleton 200 to ensure that it fully wets the second pores of the reinforcing body 220. After casting, it is left to cure at a temperature higher than room temperature to form a high-strength, high-impact-resistant cover 100.

[0075] The assembly process of the explosion-proof layer 110 and the heat-conducting layer 120 is as follows:

[0076] ① Preform preparation: Place the explosion-proof layer 110 preform, which has been three-dimensionally woven and impregnated with boron nitride-epoxy resin mixture, into the lower mold of the hot press mold. At the same time, cut the fireproof layer, which has been embedded with boron nitride filler and dried, into the required shape.

[0077] ②Layering: The cut fireproof layer is precisely laid on the inner surface of the explosion-proof layer 110 preform.

[0078] ③ Hot-press curing: The upper mold of the hot-press mold is closed, pressure is applied, and heat is applied simultaneously. Under the action of temperature and pressure, the boron nitride-epoxy resin in the explosion-proof layer 110 softens and becomes fluid, partially penetrating into the first pores of the fireproof felt 121 of the fireproof layer under pressure. At the same time, the heat causes the epoxy resin to undergo a cross-linking reaction, achieving complete curing.

[0079] ④ Cooling and demolding: Maintain pressure until curing is complete, cool to below room temperature, release pressure, and demold to obtain an integrated explosion-proof device.

[0080] Please see Figure 4 Through this process, the fireproof layer and the heat-conducting layer 120 form a "mortise and tenon" mechanical interlocking structure and a high-strength chemical bond in the interface area, characterized by epoxy resin penetration and interweaving. This achieves a seamless interface bond, ensuring efficient heat conduction between layers and the integrity of the structure under extreme conditions.

[0081] The boron nitride embedded in the fireproof layer forms a directional heat transfer path, rapidly guiding the heat generated during cable joint operation from the inside to the outside. Meanwhile, the boron nitride-modified epoxy resin in the explosion-proof layer 110 further diffuses and dissipates heat laterally. Simultaneously, the extremely low thermal conductivity of the fireproof felt 121 constitutes a highly efficient heat insulation barrier, preventing the high temperatures of an external fire from penetrating the interior. This "internal conduction and external dissipation + intermediate insulation" mechanism perfectly balances the requirements of high thermal conductivity (ensuring normal operating current carrying capacity) and high-temperature insulation (fireproofing).

[0082] Another embodiment provides a power transmission line including a first cable, a second cable, a cable joint, and an explosion-proof device as described above. The first cable is connected to the second cable through the cable joint, and a sheath 100 is fitted over the cable joint.

[0083] In the aforementioned transmission line, the sheath 100 is fitted over the cable joint to provide protective enclosure. When the cable joint explodes, a large amount of heat and high-pressure impact are generated inside the sheath 100. This heat is transferred to the shape memory element 210, causing its temperature to exceed a preset temperature. The restoring force generated by the shape memory element 210 then counteracts the high-pressure impact on the inside of the sheath 100 caused by the cable joint explosion, allowing the sheath 100 to return to its original shape after the explosion. Compared to traditional technologies, this transmission line utilizes the restoring force generated by the heated shape memory element 210 to counteract the high-pressure impact on the inside of the sheath 100, enhancing the sheath 100's resistance to pressure shocks. This prevents the explosion-proof device from rupturing and failing, thereby effectively improving the safety of power grid operation and on-site personnel.

[0084] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0085] The above embodiments merely illustrate several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. An explosion-proof device, characterized in that, include: A sleeve, which is used to cover the outside of a cable joint; A skeleton, the skeleton including a shape memory, the shape memory being disposed in the envelope; When the temperature of the shape memory is higher than a preset temperature, the shape memory can generate a restoring force so that the deformed cover can return to its original shape.

2. The explosion-proof device according to claim 1, characterized in that, The shape memory element is ring-shaped and arranged around the axial direction of the envelope.

3. The explosion-proof device according to claim 1, characterized in that, The shape memory is provided in at least two parts, and the at least two shape memory are spaced apart along the axial direction of the envelope.

4. The explosion-proof device according to claim 3, characterized in that, The skeleton also includes a reinforcement that extends along the axial direction of the envelope and intersects with at least one of the shape memory elements.

5. The explosion-proof device according to claim 4, characterized in that, The reinforcing body is provided in at least two parts, and the at least two reinforcing bodies are arranged at intervals along the circumference of the cover.

6. The explosion-proof device according to claim 1, characterized in that, The envelope includes an explosion-proof layer and a thermally conductive layer, with the explosion-proof layer covering the thermally conductive layer and the skeleton located inside the explosion-proof layer.

7. The explosion-proof device according to claim 6, characterized in that, The thermally conductive layer includes a fireproof felt and a thermally conductive filler. The fireproof felt has a first pore, and the thermally conductive filler is filled in the first pore.

8. The explosion-proof device according to claim 7, characterized in that, The explosion-proof layer includes castable filler, which is wrapped around the skeleton, and at least a portion of the castable filler fills the first pores.

9. The explosion-proof device according to claim 8, characterized in that, The skeleton has a second pore, and at least a portion of the casting filler is filled in the second pore.

10. A power transmission line, characterized in that, The power transmission line includes a first cable, a second cable, a cable joint, and an explosion-proof device as described in any one of claims 1-9, wherein the first cable is connected to the second cable through the cable joint, and the sheath is fitted over the cable joint.

Images