Fireproof flame-retardant communication cable

Abstract

The invention discloses a fire-resistant flame-retardant communication cable, which relates to the technical field of communication cables and comprises a conductor arranged in the center of a cable axis and provided with a wire, an insulating layer arranged on the outer side of the conductor, and a combined fire-resistant layer composed of three fire-resistant layers, interlamellar spacing exists among the three fire-resistant layers, and the interlamellar spacing is reduced after the temperature of the cable rises. A first guide groove is formed in the outer side of the combined refractory layer, the isolation layer is arranged on the outer side of the combined refractory layer, a second guide groove is formed in the inner side of the isolation layer, the second guide groove corresponds to the first guide groove, an expansion unit is arranged in the expansion cavity, and the expansion unit expands after being heated to a first temperature; the expansion units are arranged in the fireproof layer and the isolation layer, the leakage prevention unit is unlocked along with temperature rise in a fire disaster, the expansion units are heated to rapidly expand to form a fireproof plug, a gap between cable layers and an axial channel are tightly plugged, and the effect of accurately preventing flame from spreading in the axial direction of the cable is achieved.

Description

Technical Field

[0001] This invention relates to the field of communication cable technology, specifically to a fire-resistant and flame-retardant communication cable. Background Technology

[0002] Fire-resistant and flame-retardant communication cables are core transmission equipment in critical fields such as construction, industrial control, rail transportation, and ships. They are mainly used to maintain uninterrupted communication links in extreme environments such as fires. Their core properties must be both fire-resistant and flame-retardant to ensure that signal transmission is not interrupted for a specified time when a fire occurs, while reducing the risk of secondary disasters caused by the spread of flames. They are an important basic component for ensuring emergency communication and personnel safety in critical scenarios. Existing fire-resistant and flame-retardant communication cables lack specific structures designed to block axial flames. They rely solely on the stacking of conventional layers such as fire-resistant layers, protective layers, and outer sheaths for fire protection, using the inherent thermal insulation properties of these materials to prevent heat conduction to the core conductor. The protective layers and outer sheaths are made of low-smoke, halogen-free flame-retardant materials, primarily assisting in fire protection by inhibiting their own combustion and reducing the rate of flame spread. However, this design, which relies solely on the stacking of layers, has significant drawbacks. Due to inherent limitations in the forming processes of each layer (such as wrapping tension and longitudinal seam accuracy), and the differences in the thermal expansion coefficients and mechanical strengths of different layers, tiny gaps inevitably remain between the layers during production. Under conditions such as cable bending during installation, vibration during long-term use, or changes in ambient temperature, these initial gaps will further stretch and expand, forming continuous axial channels. In a fire environment, these channels become natural pathways for the rapid propagation of flames and high-temperature smoke. High-temperature airflow can use these gaps to break through the passive protection of conventional layers and spread rapidly along the cable axis, accelerating the burning rate of the cable in areas not directly on fire. Summary of the Invention

[0003] The purpose of this invention is to provide a fire-resistant and flame-retardant communication cable to solve the problems mentioned in the background art.

[0004] To achieve the above objectives, the present invention provides the following technical solution: a fire-resistant and flame-retardant communication cable, comprising: a conductor disposed at the center of the cable axis, and having wires disposed thereon; An insulating layer is disposed on the outside of the conductor; The composite fire-resistant layer consists of three fire-resistant layers with interlayer spacing. The interlayer spacing decreases as the cable temperature rises. A first guide groove is provided on the outer side of the composite fire-resistant layer. An isolation layer is disposed on the outside of the combined fire-resistant layer. A second guide groove is provided on the inner side of the isolation layer. The second guide groove corresponds to the first guide groove and is combined to form an expansion cavity. An expansion unit is disposed in the expansion cavity. The expansion unit expands after being heated to a first temperature. The isolation layer includes a leak-proof unit, which is housed in the expansion cavity. The leak-proof unit creates a gap after being heated to the first temperature. A sealing layer is disposed outside the isolation layer. The sealing layer includes a fire extinguishing unit. After the expansion unit expands, the fire extinguishing unit sprays fire extinguishing powder onto the outside of the cable.

[0005] Preferably, the leak-proof unit includes two connecting rings, a sleeve ring, and a first spring. The two connecting rings are connected by a hot-melt material. When the leak-proof unit is heated to a first temperature, the hot-melt material melts, and the two connecting rings are disconnected. The sleeve ring is sleeved on one side of the connecting ring. The side of the sleeve ring connected to the connecting ring has a hollow cavity. The first spring is provided in the hollow cavity. The connecting ring can move along the hollow cavity. The connecting ring is connected to the sleeve ring through the first spring.

[0006] Preferably, the fire extinguishing unit includes a fixing ring, a pressure ring, a fire extinguishing airbag, and a fire extinguishing nozzle. The fixing ring has an annular inner cavity, and the fire extinguishing airbag is disposed in the annular inner cavity. The fire extinguishing airbag is compressible and its inner cavity is filled with fire extinguishing powder. The pressure ring is disposed at the outermost edge of the annular inner cavity, making the annular inner cavity a hollow chamber. The pressure ring can deform when squeezed and can extend along the annular inner cavity. The fire extinguishing nozzle is disposed on the outside of the fire extinguishing airbag and communicates with the inner cavity of the fire extinguishing airbag. One end of the fire extinguishing nozzle passes through the outside of the fixing ring. When the fire extinguishing airbag is compressed, the fire extinguishing powder is sprayed out through the fire extinguishing nozzle.

[0007] Preferably, the composite refractory layer is composed of a first refractory layer, a second refractory layer, and a third refractory layer arranged coaxially, and there are gaps between the first refractory layer, the second refractory layer, and the third refractory layer. A slider is provided between the first refractory layer and the second refractory layer, and the second refractory layer and the third refractory layer are respectively provided with mating grooves. The slider and the mating groove have a reserved distance, and the slider can be embedded in the inner cavity of the mating groove.

[0008] Preferably, the fire extinguishing nozzle includes a fixed base and a valve plate. The fixed base has two chambers: a first chamber and a second chamber. The direction of the first chamber is set as a first direction. In a first state, the valve plate is located in the inner cavity of the second chamber and is in contact with the inner wall of the second chamber. In a second state, it is located in the inner cavity of the first chamber and has a gap with the inner wall of the first chamber.

[0009] Preferably, the inner wall of the second chamber is provided with a fitting groove, and a stop block and a second spring are provided in the fitting groove. The stop block can move along the fitting groove, and the stop block and the fitting groove are connected by the second spring. When the valve plate is in the first state, it is blocked from entering the first chamber by the stop block. One side of the stop block is set at an angle. When the valve plate is subjected to a pushing force in the first direction, it squeezes the inclined surface of the stop block and causes the stop block to move into the inner cavity of the fitting groove, so that the valve plate is not blocked.

[0010] Preferably, the outer side of the sealing layer is wrapped with an outer sheath, and the outer sheath has a reserved gap, so that the extinguishing powder can pass through the gap and be sprayed on the outside of the sealing layer for fire extinguishing.

[0011] Preferably, the conductor has inner and outer double layers, both the inner and outer layers are provided with a plurality of dividing slots, the wires are arranged in the dividing slots, and the conductors and dividing slots are interference fit.

[0012] Preferably, the expansion unit is made of a material that expands when heated, and the first temperature is the critical temperature at which the material expands. The slider, the anti-leakage unit, and the fire extinguishing unit are arranged along the cable axis and correspond to each other.

[0013] Preferably, when the expansion unit is not heated and expanded, the valve plate is in the first state. After the expansion unit is heated and expanded, the fire extinguishing airbag is compressed and generates pressure, which causes the valve plate to be pushed in the first direction and enter the first chamber, where it is in the second state.

[0014] Compared with the prior art, the beneficial effects of the present invention are: In this invention, by setting expansion units in the fire-resistant layer and the isolation layer, the anti-leakage unit unlocks as the temperature rises during a fire, and the expansion unit expands rapidly when heated to form a fireproof plug, which tightly seals the gap between cable layers and the axial channel, thereby achieving the effect of accurately blocking the spread of flames along the cable axial direction. 2. In this invention, by setting a fire extinguishing unit in the sealed layer, the expansion unit simultaneously squeezes the fire extinguishing unit when it expands, causing it to spray fire extinguishing agent to cover the outer layer of the cable. On the basis of blocking the axial spread of flames, it further extinguishes the open flames on the outer layer of the cable and forms a protective layer, achieving the dual protection effect of sealing and fire extinguishing. 3. In this invention, protrusions are set between the three fire-resistant layers to maintain the gap between the layers and preserve the flexibility of the cable. When a fire occurs, the expansion unit expands to make the three fire-resistant layers fit tightly against the sealed heat insulation barrier, thereby strengthening the heat insulation performance of the fire-resistant layer and solving the problem of heat insulation failure of the fire-resistant layer at high temperatures. Attached Figure Description

[0015] Figure 1 This is a schematic cross-sectional view of a fire-resistant and flame-retardant communication cable according to the present invention; Figure 2This is a cross-sectional view of the insulation layer in a fire-resistant and flame-retardant communication cable according to the present invention; Figure 3 For the present invention Figure 2 Enlarged view of the structure of area A in the middle; Figure 4 This is a structural exploded view of the anti-leakage unit in a fire-resistant and flame-retardant communication cable according to the present invention; Figure 5 This is a schematic diagram of the overall structure of the sealing layer in a fire-resistant and flame-retardant communication cable according to the present invention; Figure 6 This is a structural exploded view of the fire extinguishing unit in a fire-resistant and flame-retardant communication cable according to the present invention; Figure 7 This is a cross-sectional view of a fire extinguishing nozzle in a fire-resistant and flame-retardant communication cable according to the present invention. Figure 8 This is a schematic diagram of the longitudinal section of the composite fire-resistant layer in a fire-resistant and flame-retardant communication cable according to the present invention; Figure 9 For the present invention Figure 8 Enlarged view of the structure in area B.

[0016] In the diagram: 100, conductor; 110, wire; 200, insulation layer; 300, combined fire-resistant layer; 310, first fire-resistant layer; 320, second fire-resistant layer; 330, third fire-resistant layer; 340, slider; 350, mating groove; 400, isolation layer; 410, leak-proof unit; 411, connecting ring; 412, sleeve ring; 413, first spring; 420, locking clamp; 430, expansion chamber; 500, sealing layer; 510, fire extinguishing unit; 511, fixing ring; 512, pressure ring; 513, fire extinguishing airbag; 514, fire extinguishing nozzle; 5141, fixing seat; 5142, first chamber; 5143, second chamber; 5144, valve plate; 5145, stop block; 5146, second spring; 5147, fitting groove; 600, outer sheath. Detailed Implementation

[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] Reference Figures 1-3 As shown: A fire-resistant and flame-retardant communication cable, comprising: Conductor 100 is located at the center of the cable axis and is provided with wire 110; An insulating layer 200 is disposed on the outside of the conductor 100; The combined fire-resistant layer 300 consists of three fire-resistant layers with interlayer spacing between them. The interlayer spacing decreases as the cable temperature rises. A first guide groove is provided on the outer side of the combined fire-resistant layer 300. An isolation layer 400 is disposed on the outside of the combined fire-resistant layer 300. A second guide groove is formed on the inner side of the isolation layer 400. The second guide groove corresponds to the first guide groove and is combined to form an expansion cavity 430. An expansion unit is disposed in the expansion cavity 430. The expansion unit expands after being heated to a first temperature. The isolation layer 400 includes a leak-proof unit 410, which is accommodated in the expansion cavity 430. The leak-proof unit 410 creates a gap after being heated to the first temperature. A sealing layer 500 is disposed outside the isolation layer 400. The sealing layer 500 includes a fire extinguishing unit 510. After the expansion unit expands, the fire extinguishing unit 510 sprays fire extinguishing powder onto the outside of the cable.

[0019] In this embodiment, when the cable catches fire, the anti-discharge unit 410 is heated to a first temperature, creating a gap. The expansion unit, located in the expansion cavity 430, is also heated to the first temperature, causing it to expand. Both sides of the expansion cavity 430 are provided with inclined guide structures, allowing the expansion unit to expand radially toward the isolation layer 400. This causes the isolation layer 400 to deform on both sides of the expansion cavity 430, compressing the combined fire-resistant layer 300 and the sealing layer 500. When the combined fire-resistant layer 300 is compressed, the interlayer spacing of the three fire-resistant layers decreases, allowing the three fire-resistant layers to tightly adhere to a sealed heat insulation barrier, enhancing the heat insulation performance of the fire-resistant layer. When the sealing layer 500 is compressed, the fire extinguishing unit 510 sprays fire extinguishing powder onto the outside of the cable, extinguishing the open flames on the outside of the cable. Locking clamps 420 are provided on both sides of the expansion cavity 430 on the outside of the isolation layer 400 to prevent the expansion unit from expanding axially.

[0020] according to Figure 4 As shown, the leak-proof unit 410 includes two connecting rings 411, a sleeve ring 412, and a first spring 413. The two connecting rings 411 are connected by a hot-melt material. When the leak-proof unit 410 is heated to a first temperature, the hot-melt material melts, and the two connecting rings 411 are disconnected. The sleeve ring 412 is sleeved on one side of the connecting ring 411. The side of the sleeve ring 412 connected to the connecting ring 411 has a hollow cavity. The first spring 413 is provided in the hollow cavity. The connecting ring 411 can move along the hollow cavity. The connecting ring 411 is connected to the sleeve ring 412 through the first spring 413.

[0021] In this embodiment, when the anti-leakage unit 410 is heated to the first temperature, the hot melt material between the two connecting rings 411 melts. The hot melt material can be a low melting point alloy or a hot melt ceramic adhesive. The first spring 413, which was initially in a stretched state, returns to its original state, causing the two connecting rings 411 to move into the hollow cavity of the sleeve ring 412 respectively. A gap is generated between the two connecting rings 411, and heat enters the expansion cavity 430, heating the expansion unit and allowing the expansion unit to extend in both directions.

[0022] according to Figures 5-6 As shown, the fire extinguishing unit 510 includes a fixing ring 511, a pressure ring 512, a fire extinguishing airbag 513, and a fire extinguishing nozzle 514. The fixing ring 511 has an annular inner cavity. The fire extinguishing airbag 513 is disposed in the annular inner cavity. The fire extinguishing airbag 513 can be compressed and its inner cavity is filled with fire extinguishing powder. The pressure ring 512 is disposed at the outermost edge of the annular inner cavity, making the annular inner cavity a hollow chamber. The pressure ring 512 can deform when squeezed and can extend along the annular inner cavity. The fire extinguishing nozzle 514 is disposed on the outside of the fire extinguishing airbag 513 and communicates with the inner cavity of the fire extinguishing airbag 513. One end of the fire extinguishing nozzle 514 passes through the outside of the fixing ring 511. When the fire extinguishing airbag 513 is compressed, the fire extinguishing powder is sprayed out through the fire extinguishing nozzle 514.

[0023] In this embodiment, when the expansion unit expands, it squeezes the pressure ring 512, causing the pressure ring 512 to deform and extend into the annular inner cavity of the fixed ring 511. Since the fire extinguishing airbag 513 is located in the annular inner cavity, the pressure ring 512 squeezes the fire extinguishing airbag 513 to compress it. When the fire extinguishing airbag 513 is compressed, positive pressure is generated inside. Under the action of pressure, the fire extinguishing powder is sprayed out through the fire extinguishing nozzle 514.

[0024] according to Figures 8-9 As shown, the composite refractory layer 300 is composed of a first refractory layer 310, a second refractory layer 320, and a third refractory layer 330 arranged coaxially, and there are gaps between the first refractory layer 310, the second refractory layer 320, and the third refractory layer 330. A slider 340 is provided between the first refractory layer 310 and the second refractory layer 320. The second refractory layer 320 and the third refractory layer 330 are respectively provided with mating grooves 350. The slider 340 and the mating groove 350 have a reserved distance, and the slider 340 can be embedded in the inner cavity of the mating groove 350.

[0025] In this embodiment, a slider 340 is provided between the first fire-resistant layer 310, the second fire-resistant layer 320, and the third fire-resistant layer 330. The slider 340 creates gaps between the layers, ensuring the bending flexibility of the cable at room temperature. When the expansion unit compresses the combined fire-resistant layer 300, the slider 340 can move along the inner side of each fire-resistant layer. One side of the slider 340 is set as an inclined surface. When the combined fire-resistant layer 300 is compressed, each fire-resistant layer is compressed and extends to both sides, causing the slider 340 to move. When the slider 340 moves to the mating groove 350, the slider 340 is embedded in the mating groove 350, causing the gaps between the fire-resistant layers to disappear and completely closing the original interlayer gaps, forming a dense heat insulation barrier without pores.

[0026] according to Figure 7 As shown, the fire extinguishing nozzle 514 includes a fixed base 5141 and a valve plate 5144. The fixed base 5141 has two chambers: a first chamber 5142 and a second chamber 5143. The direction of the first chamber 5142 is set as the first direction, such as... Figure 7 In the direction indicated by the arrow, the valve plate 5144 is located in the inner cavity of the second chamber 5143 in the first state and is in contact with the inner wall of the second chamber 5143. In the second state, it is located in the inner cavity of the first chamber 5142 and has a gap with the inner wall of the first chamber 5142.

[0027] In this embodiment, when the valve plate 5144 is in the first state, it is in contact with the inner wall of the second chamber 5143 to prevent the extinguishing powder in the inner cavity of the fire extinguishing airbag 513 from leaking. When the valve plate 5144 is in the second state, it enters the inner cavity of the first chamber 5142. At the same time, when the valve plate 5144 is in the second state, positive pressure is generated in the inner cavity of the fire extinguishing airbag 513. Under the pressure, the extinguishing powder is sprayed out through the gap between the valve plate 5144 and the first chamber 5142.

[0028] Continue according to Figure 7 As shown, the inner wall of the second chamber 5143 is provided with a fitting groove 5147. A stop block 5145 and a second spring 5146 are provided in the fitting groove 5147. The stop block 5145 can move along the fitting groove 5147. The stop block 5145 and the fitting groove 5147 are connected by the second spring 5146. When the valve plate 5144 is in the first state, it is blocked from entering the first chamber 5142 by the stop block 5145. One side of the stop block 5145 is set at an angle. When the valve plate 5144 is pushed in the first direction, it squeezes the inclined surface of the stop block 5145, causing the stop block 5145 to move into the inner cavity of the fitting groove 5147, so that the valve plate 5144 is not blocked.

[0029] In this embodiment, when the valve plate 5144 is in the first state, it is blocked by the stop block 5145 to prevent it from entering the second state and causing the extinguishing powder to leak. When pressure is generated inside the extinguishing airbag 513, the valve plate 5144 is pushed upward by the first direction. The pushing force continues to act on the inclined surface of the stop block 5145, causing the stop block 5145 to enter the inner cavity of the fitting groove 5147. At the same time, the pushing force exceeds the elastic force of the second spring 5146, causing the valve plate 5144 to enter the first chamber 5142. The valve plate 5144 is no longer blocked and enters the first chamber 5142.

[0030] according to Figure 1 As shown, the outer side of the sealing layer 500 is wrapped with an outer sheath 600, and the outer sheath 600 has a reserved gap, so that the extinguishing powder can pass through the gap and be sprayed on the outside of the sealing layer 500 for fire extinguishing.

[0031] In this embodiment, the fire extinguishing powder sprayed by the fire extinguishing nozzle 514 can be sprayed onto the outside of the cable through the gap in the outer sheath 600, extinguishing the fire while forming an isolation zone to prevent the flame from continuing to spread axially.

[0032] according to Figure 1 As shown, the conductor 100 has inner and outer double layers, and both the inner and outer layers are provided with a number of dividing slots. The wire 110 is arranged in the dividing slots, and the conductor 100 and the dividing slots are both interference fit.

[0033] In this embodiment, the spacing between the conductors 110 is increased to effectively reduce heat accumulation. At the same time, the interference fit design ensures that the position of the conductors 110 is fixed and avoids misalignment when bending.

[0034] according to Figures 1-2 As shown, the expansion unit is made of a material that expands when heated, and the first temperature is the critical temperature at which the material expands. The slider 340, the anti-leakage unit 410, and the fire extinguishing unit 510 are arranged along the cable axis and correspond to each other.

[0035] In this embodiment, the expansion unit can be made of ceramicized expandable silicone rubber or expandable graphite. When the leak prevention unit 410 creates a gap, the expansion material in the expansion cavity 430 expands, and the isolation layer 400 deforms in the expansion cavity 430. Since the slider 340, the fire extinguishing unit 510 and the leak prevention unit 410 correspond to each other, the deformation point of the isolation layer 400 generates a thrust that acts on the slider 340 and the fire extinguishing unit 510.

[0036] according to Figure 7 As shown, when the expansion unit is not heated and expanded, the valve plate 5144 is in the first state. After the expansion unit is heated and expanded, the fire extinguishing airbag 513 is compressed and generates pressure, which causes the valve plate 5144 to be subjected to a thrust in the first direction, pushing the valve plate 5144 into the first chamber 5142 and then into the second state.

[0037] In this embodiment, when the expansion unit is not heated and expanded, the pressure ring 512 does not squeeze the fire extinguishing airbag 513, so that the fire extinguishing airbag 513 is in an initial uncompressed state and does not generate sufficient pressure, so that the valve plate 5144 does not receive sufficient thrust, and thus the valve plate 5144 is blocked by the stop block 5145. When the expansion unit expands, the valve plate 5144 enters the second state.

[0038] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A fire-resistant and flame-retardant communication cable, characterized in that: include: A conductor (100) is located at the center of the cable axis and is provided with a wire (110). An insulating layer (200) is disposed on the outside of the conductor (100); The combined fire-resistant layer (300) consists of three fire-resistant layers with interlayer spacing between them. The interlayer spacing decreases as the cable temperature rises. A first guide groove is provided on the outer side of the combined fire-resistant layer (300). An isolation layer (400) is disposed on the outside of the combined fire-resistant layer (300). A second guide groove is provided on the inner side of the isolation layer (400). The second guide groove corresponds to the first guide groove and is combined to form an expansion cavity (430). An expansion unit is disposed in the expansion cavity (430). The expansion unit expands after being heated to a first temperature. The isolation layer (400) includes a leak-proof unit (410). The leak-proof unit (410) is accommodated in the expansion cavity (430). The leak-proof unit (410) creates a gap after being heated to a first temperature. A sealing layer (500) is disposed outside the isolation layer (400). The sealing layer (500) includes a fire extinguishing unit (510). After the expansion unit expands, the fire extinguishing unit (510) sprays fire extinguishing powder onto the outside of the cable.

2. The fire-resistant and flame-retardant communication cable according to claim 1, characterized in that: The leak-proof unit (410) includes two connecting rings (411), a sleeve ring (412), and a first spring (413). The two connecting rings (411) are connected by a hot melt material. When the leak-proof unit (410) is heated to a first temperature, the hot melt material melts, and the two connecting rings (411) are disconnected. The sleeve ring (412) is sleeved on one side of the connecting ring (411). The connecting side of the sleeve ring (412) and the connecting ring (411) has a hollow cavity. The first spring (413) is provided in the hollow cavity. The connecting ring (411) can move along the hollow cavity. The connecting ring (411) is connected to the sleeve ring (412) through the first spring (413).

3. The fire-resistant and flame-retardant communication cable according to claim 2, characterized in that: The fire extinguishing unit (510) includes a fixing ring (511), a pressure ring (512), a fire extinguishing airbag (513), and a fire extinguishing nozzle (514). The fixing ring (511) has an annular inner cavity. The fire extinguishing airbag (513) is disposed in the annular inner cavity. The fire extinguishing airbag (513) can be compressed and its inner cavity is filled with fire extinguishing powder. The pressure ring (512) is disposed at the outermost edge of the annular inner cavity to form a hollow chamber. The pressure ring (512) can deform after being squeezed and can extend along the annular inner cavity. The fire extinguishing nozzle (514) is disposed on the outside of the fire extinguishing airbag (513) and communicates with the inner cavity of the fire extinguishing airbag (513). One end of the fire extinguishing nozzle (514) passes through the outside of the fixing ring (511). When the fire extinguishing airbag (513) is compressed, the fire extinguishing powder is sprayed out through the fire extinguishing nozzle (514).

4. The fire-resistant and flame-retardant communication cable according to claim 3, characterized in that: The composite refractory layer (300) is composed of a first refractory layer (310), a second refractory layer (320), and a third refractory layer (330) arranged coaxially. The first refractory layer (310), the second refractory layer (320), and the third refractory layer (330) have gaps between each other. A slider (340) is provided between the first refractory layer (310) and the second refractory layer (320). The second refractory layer (320) and the third refractory layer (330) are respectively provided with mating grooves (350). The slider (340) and the mating groove (350) have a reserved distance, and the slider (340) can be embedded in the inner cavity of the mating groove (350).

5. A fire-resistant and flame-retardant communication cable according to claim 3, characterized in that: The fire extinguishing nozzle (514) includes a fixed base (5141) and a valve plate (5144). The fixed base (5141) has two chambers: a first chamber (5142) and a second chamber (5143). The direction of the first chamber (5142) is set as a first direction. In the first state, the valve plate (5144) is located in the inner cavity of the second chamber (5143) and is in contact with the inner wall of the second chamber (5143). In the second state, it is located in the inner cavity of the first chamber (5142) and has a gap with the inner wall of the first chamber (5142).

6. The fire-resistant and flame-retardant communication cable according to claim 5, characterized in that: The inner wall of the second chamber (5143) is provided with a fitting groove (5147). A stop block (5145) and a second spring (5146) are provided in the fitting groove (5147). The stop block (5145) can move along the fitting groove (5147). The stop block (5145) and the fitting groove (5147) are connected by the second spring (5146). When the valve plate (5144) is in the first state, it is blocked from entering the first chamber (5142) by the stop block (5145). One side of the stop block (5145) is set at an angle. When the valve plate (5144) is pushed in the first direction, it squeezes the inclined surface of the stop block (5145) to move the stop block (5145) into the inner cavity of the fitting groove (5147) so that the valve plate (5144) is not blocked.

7. The fire-resistant and flame-retardant communication cable according to claim 1, characterized in that: The outer side of the sealing layer (500) is wrapped with an outer sheath (600), and the outer sheath (600) has a reserved gap, so that the extinguishing powder can pass through the gap and be sprayed on the outside of the sealing layer (500) for fire extinguishing.

8. The fire-resistant and flame-retardant communication cable according to claim 1, characterized in that: The conductor (100) has inner and outer double layers, and both the inner and outer layers are provided with a number of dividing slots. The wire (110) is arranged in the dividing slots, and the conductor (100) and the dividing slots are both interference fit.

9. A fire-resistant and flame-retardant communication cable according to claim 4, characterized in that: The expansion unit is made of a material that expands when heated, and the first temperature is the critical temperature at which the material expands. The slider (340), the anti-leakage unit (410), and the fire extinguishing unit (510) are arranged along the cable axis and correspond to each other.

10. A fire-resistant and flame-retardant communication cable according to claim 5, characterized in that: When the expansion unit is not heated and expanded, the valve plate (5144) is in the first state. After the expansion unit is heated and expanded, the fire extinguishing airbag (513) is compressed and generates pressure, which causes the valve plate (5144) to be pushed in the first direction and enter the first chamber (5142) and then enters the second state.

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