Flame-retardant fireproof marine control cable and manufacturing method thereof

Abstract

The invention discloses a flame-retardant fireproof marine control cable and a manufacturing method thereof, and relates to the technical field of cable manufacturing, the flame-retardant fireproof marine control cable comprises a cable core assembly, a fireproof thermal insulation layer, a buffer support layer and an outer sheath layer; the cable core assembly comprises a plurality of spirally-twisted signal transmission wire cores and a central reinforcing piece, so that signal transmission and structural strength are guaranteed. The fireproof heat insulation layer is of a three-layer structure, and heat and flames are effectively blocked; the buffering supporting layer is composed of an annular elastic supporting piece and a buffering material and buffers external impact. Longitudinal reinforcing ribs are arranged in the outer sheath layer, and the outer surface of the outer sheath layer is provided with antiskid lines, thereby improving wear resistance, extrusion resistance and installation convenience. The steps of the manufacturing method are tightly matched, the quality performance of each layer of the cable is ensured, industrial large-scale production is adapted, and the harsh requirements of ship complex environments on the cable are met.

Description

Technical Field

[0001] The present invention relates to the technical field of cable manufacturing, and in particular to a flame-retardant and fire-resistant shipboard control cable and a manufacturing method thereof. Background Art

[0002] During ship operation, marine control cables must endure harsh environments such as high temperatures, humidity, and vibration. In the event of a fire, ordinary cables are not only prone to combustion but also serve as a pathway for the fire to spread. Furthermore, signal transmission stability cannot be guaranteed at high temperatures, posing a serious threat to the safety of the vessel and personnel.

[0003] As disclosed in a Chinese invention patent for a flame-retardant and fire-resistant shipboard control cable and a manufacturing method thereof (authorization announcement number: CN103226999B, authorization announcement date: 2015.12.09), the outer periphery of the stranded copper conductor is uniformly extruded with a flame-retardant and fire-resistant EPDM rubber insulation layer to form an insulated core of the control cable, and multiple insulated cores of the control cable are twisted together to form a control cable core. The outer periphery of the control cable core is wrapped with a low-strength non-woven fabric longitudinal sheath, the outer periphery of the low-strength non-woven fabric longitudinal sheath is extruded with an inner sheath, the outer periphery of the inner sheath is covered with an armored braided layer, and the outer periphery of the armored braided layer is extruded with an outer sheath.

[0004] Some existing flame-retardant and fire-resistant shipboard cables have problems in their structural design, such as insufficient cable core protection, easy detachment of the fireproof layer, and poor mechanical buffering performance. They are unable to meet the long-term reliable operation requirements of ships under complex working conditions. Summary of the Invention

[0005] The purpose of the present invention is to solve the shortcomings of the prior art such as insufficient cable core protection, easy detachment of the fireproof layer, and poor mechanical buffering performance, and to propose a flame retardant and fire-resistant shipboard control cable and a manufacturing method thereof.

[0006] In order to solve the problems existing in the prior art, the present invention adopts the following technical solutions: A flame-retardant and fire-resistant shipboard control cable, comprising a cable core assembly, a fireproof and heat-insulating layer, a buffer support layer and an outer sheath layer; The cable core assembly is composed of a plurality of signal transmission cores and a central reinforcement member, wherein the plurality of signal transmission cores are twisted and arranged in a spiral shape around the central reinforcement member; The fireproof and heat-insulating layer is coated on the outside of the cable core assembly and adopts a three-layer composite structure design; The buffer support layer is located between the fireproof and heat-insulating layer and the outer sheath layer, and is composed of a plurality of annular elastic support members and a buffer material filling the gaps between the annular elastic support members; The outer sheath layer is sleeved on the outer surface of the buffer support layer. A plurality of spirally distributed longitudinal reinforcing ribs are arranged inside the outer sheath layer. A plurality of evenly distributed anti-slip lines are opened on the outer surface of the outer sheath layer.

[0007] Preferably, the signal transmission core consists of a conductor, an insulation layer and a shielding layer, wherein the conductor is twisted with high-purity oxygen-free copper wire, the insulation layer is made of polytetrafluoroethylene propylene material with high temperature resistance and excellent flame retardant properties, has uniform thickness, and is tightly wrapped around the outside of the conductor, and the shielding layer is a tinned copper wire braided layer covering the surface of the insulation layer.

[0008] Preferably, the central reinforcement is made of glass fiber reinforced plastic rod.

[0009] Preferably, the inner layer of the fireproof and heat-insulating layer is a ceramic silicone rubber layer, the middle layer of the fireproof and heat-insulating layer is an aerogel felt layer, and the outer layer of the fireproof and heat-insulating layer is an intumescent fireproof coating.

[0010] Preferably, the annular elastic support member is made of silicone rubber, a plurality of raised support blocks are provided on the inner side of the annular elastic support member, and a plurality of oblique notches are provided on the outer side of the annular elastic support member.

[0011] Preferably, the buffer material is melamine foam.

[0012] Preferably, both the inner and outer surfaces of the outer sheath layer are coated with a uniformly distributed low-smoke halogen-free flame-retardant polyolefin layer, and the inner surface of the outer sheath layer is provided with a plurality of spiral chutes distributed in a spiral pattern.

[0013] Preferably, an aramid fiber braided belt is installed inside each of the spiral chutes, and each of the aramid fiber braided belts passes through and is engaged in the corresponding oblique notch in sequence.

[0014] Preferably, the interior of the aramid fiber braided belt is a hollow structure, and the longitudinal reinforcing ribs are adapted to be installed inside the aramid fiber braided belt.

[0015] The present invention also provides a method for manufacturing a flame-retardant and fire-resistant shipboard control cable, comprising the following steps: The cable core assembly manufacturing steps are as follows: High-purity oxygen-free copper wire with a diameter of 0.5mm is selected and twisted into 7 strands to form a conductor with an outer diameter of 1.2mm. An insulation layer with a thickness of 0.3mm is wrapped around the conductor using an extrusion process. A shielding layer with an 85% coverage is then braided over the insulation layer to form a signal transmission core. The six signal transmission cores are then spirally twisted around a glass fiber reinforced plastic rod with a diameter of 2mm. The twisting pitch is 20mm to form the cable core assembly. The manufacturing steps of the fireproof and heat-insulating layer are as follows: a 0.5mm thick ceramic silicone rubber layer is coated on the outside of the cable core assembly using a coating process, a 0.3mm thick aerogel felt layer is laid on the outside of the ceramic silicone rubber layer, and finally a 0.2mm thick intumescent fire-proof coating is sprayed to form a fireproof and heat-insulating layer; The buffer support layer is manufactured by: placing an annular elastic support member with an inner diameter matching the outer diameter of the fireproof and heat-insulating layer over the outer surface of the fireproof and heat-insulating layer. The annular elastic support member has a wall thickness of 1 mm and a height of 5 mm, and eight support blocks with a height of 0.5 mm are evenly distributed on the inner surface of the annular elastic support member. Melamine foam is then filled between the annular elastic support members using a mold at a filling density of 15 kg / m³ to form the buffer support layer. The outer sheath is manufactured by heating a low-smoke, halogen-free, flame-retardant polyolefin material to 180°C and then coating it with a 1.5mm thick outer sheath. A 3mm wide aramid fiber braid is then spirally embedded into a spiral chute. A 0.3mm deep anti-slip pattern is then embossed onto the outer sheath using a mold. Finished cable testing procedures include: flame retardancy testing of finished cables, including a standard bundled combustion test. The cable's carbonization height after combustion should not exceed 2.5 meters. Fire resistance testing is also conducted, including a standard 90-minute 750°C flame test. The cable must maintain normal signal transmission during the test. Electrical testing ensures insulation resistance is no less than 1000MΩ·km, and the conductor's DC resistance meets relevant standards. Mechanical testing ensures tensile strength is no less than 50N / mm², and good bending performance is achieved after 10 bends. Cables that pass these tests are then packaged and stored.

[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. In the present invention, the rational design of the conductor, insulation layer, and shielding layer in the cable core assembly ensures good electrical conductivity, insulation performance, and anti-interference capabilities of the cable, enabling stable transmission of control signals. The provision of a central reinforcement member enhances the tensile strength of the cable and improves its mechanical reliability. 2. In the present invention, the three-layer structure design of the fireproof and heat-insulating layer, from the high-temperature ceramicization of the ceramic silicone rubber layer, the efficient heat insulation of the aerogel felt layer, to the expansion and flame retardancy of the intumescent fire-retardant coating, improves the flame retardancy and fire resistance of the cable in multiple dimensions, effectively protecting the cable core assembly from normal operation in a fire environment; 3. In the present invention, the combination of the annular elastic support member and the melamine foam in the buffer support layer can effectively absorb external vibration and impact, reducing the impact on the cable core assembly. At the same time, the support structure ensures the stability of the cable structure at each layer, thereby extending the service life of the cable. 4. In the present invention, the outer sheath layer is made of low-smoke halogen-free flame-retardant polyolefin material and is provided with longitudinal reinforcement ribs and anti-slip lines, which not only improves the flame retardancy, wear resistance and weather resistance of the cable, but also facilitates the installation and fixation of the cable, adapting to the complex use environment of ships; In summary, the manufacturing method of the present invention is reasonable, the various steps are closely coordinated, the quality and performance of each layer structure of the cable can be guaranteed, and it is suitable for industrial large-scale production. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of this application. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings: Figure 1 It is a schematic diagram of the overall structure of the present invention; Figure 2 It is a schematic cross-sectional view of the overall structure of the present invention; Figure 3 It is a structural schematic diagram of the signal transmission core of the present invention; Figure 4 Schematic diagram of the cross-section of the structure of the signal transmission core of the present invention; Figure 5 It is a schematic structural diagram of the cable assembly and the fireproof and heat-insulating layer of the present invention; Figure 6 Schematic diagram of the cross-section of the cable assembly and the fireproof and heat-insulating layer of the present invention; Figure 7 Schematic diagram of the structure of the buffer support layer and the outer protective layer of the present invention; Figure 8 Schematic diagram of the cross-section of the structure of the buffer support layer and the outer protective layer of the present invention; Figure 9 Schematic diagram of the exploded cross-section of the structure of the buffer support layer and the outer sheath protective layer of the present invention; Markings in the figure: 100, signal transmission core; 101, conductor; 102, insulation layer; 103, shielding layer; 104, central reinforcement; 200, fireproof and heat-insulating layer; 201, ceramic silicone rubber layer; 202, aerogel felt layer; 203, intumescent fire-retardant coating; 300, buffer support layer; 301, annular elastic support member; 302, support block; 303, oblique notch; 304, buffer material; 400, outer sheath layer; 401, low-smoke, halogen-free, flame-retardant polyolefin layer; 402, spiral chute; 403, aramid fiber braided belt; 404, longitudinal reinforcement ribs; 405, anti-slip texture. DETAILED DESCRIPTION

[0018] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0019] Example 1: This example provides a flame retardant and fire resistant marine control cable. Figures 1-9, specifically, including a cable core assembly, a fireproof and heat-insulating layer 200, a buffer support layer 300 and an outer sheath layer 400; The cable core assembly is composed of a plurality of signal transmission cores 100 and a central reinforcement member 104, wherein the plurality of signal transmission cores 100 are twisted and arranged in a spiral shape around the central reinforcement member 104; The signal transmission core 100 is composed of a conductor 101, an insulating layer 102 and a shielding layer 103. The conductor 101 is made of high-purity oxygen-free copper wires twisted together to reduce resistance and improve conductivity. The insulation layer 102 is made of a high-temperature-resistant and flame-retardant polytetrafluoroethylene propylene material with uniform thickness and tightly wrapped around the conductor 101, providing good insulation. The shielding layer 103 is a tinned copper wire braided layer covering the surface of the insulating layer 102, which can effectively shield external electromagnetic interference and ensure the accuracy of signal transmission; The central reinforcement 104 is made of glass fiber reinforced plastic rod, which has the characteristics of high strength and light weight. It can enhance the overall tensile strength of the cable and prevent the cable core from being damaged due to stretching during use.

[0020] In the specific implementation process, Figure 5 and Figure 6 As shown, the fireproof and heat-insulating layer 200 is coated on the outside of the cable core assembly and adopts a three-layer composite structure design. The inner layer of the fireproof and heat-insulating layer 200 is a ceramic silicone rubber layer 201, which has good flexibility at room temperature and is convenient for bending and installing the cable. When exposed to high temperatures, it can be quickly ceramicized to form a hard ceramic body, effectively blocking heat transfer. The middle layer of the fireproof and heat-insulating layer 200 is an aerogel felt layer 202. Aerogel has an extremely low thermal conductivity coefficient, which can further improve the heat insulation performance of the fireproof and heat-insulating layer 200. The outer layer of the fireproof and heat-insulating layer 200 is an intumescent fireproof coating 203. When the surface temperature of the cable rises to a certain level, the intumescent fireproof coating 203 expands rapidly to form a dense foam carbonized layer, isolating oxygen and heat and preventing the spread of flames.

[0021] In the specific implementation process, Figure 8 and Figure 9 As shown, the buffer support layer 300 is located between the fireproof and heat-insulating layer 200 and the outer sheath layer 400, and is composed of a plurality of annular elastic support members 301 and a buffer material 304 filling the gaps between the annular elastic support members 301; The annular elastic support member 301 is made of silicone rubber and has good elasticity and weather resistance. A plurality of raised support blocks 302 are provided on the inner side of the annular elastic support member 301, which can fit tightly with the fireproof and heat-insulating layer 200 to play a supporting role. A plurality of oblique notches 303 are provided on the outer side of the annular elastic support member 301 for fixing the aramid fiber braid 403 and the outer sheath layer 400. The buffer material 304 is made of melamine foam, which has the characteristics of light weight, good elasticity and flame retardancy. It can effectively absorb external vibration and impact force and reduce the impact on the cable core assembly.

[0022] In the specific implementation process, Figure 7 、 Figure 8 and Figure 9 As shown, the outer sheath layer 400 is sleeved on the outer surface of the buffer support layer 300. The inner part of the outer sheath layer 400 is provided with a plurality of spirally distributed longitudinal reinforcing ribs 404. The outer surface of the outer sheath layer 400 is provided with a number of evenly distributed anti-slip grooves 405 to facilitate the installation and fixation of the cable. The inner and outer surfaces of the outer sheath layer 400 are coated with an evenly distributed low-smoke halogen-free flame-retardant polyolefin layer 401, which has excellent flame retardancy, weather resistance and wear resistance. The inner surface of the outer sheath layer 400 is provided with a number of spiral chutes 402 distributed in a spiral pattern. An aramid fiber braid 403 is installed inside each spiral chute 402. Each aramid fiber braid 403 passes through and fits into the corresponding oblique notch 303 in sequence. The interior of the aramid fiber braid 403 is a hollow structure. The longitudinal reinforcement ribs 404 are adapted to be installed inside the aramid fiber braid 403, which can further improve the cable's resistance to tensile and extrusion.

[0023] Working Principle of this embodiment: The manufacturing steps of the cable core assembly are as follows: a high-purity oxygen-free copper wire with a diameter of 0.5 mm is selected and twisted into 7 strands to form a conductor 101 with an outer diameter of 1.2 mm; an insulation layer 102 with a thickness of 0.3 mm is wrapped around the conductor 101 using an extrusion process, and then a shielding layer 103 with a coverage of 85% is braided around the insulation layer 102 to form a signal transmission core 100. Six signal transmission cores 100 are spirally twisted around a glass fiber reinforced plastic rod with a diameter of 2 mm, with a twist pitch of 20 mm, to obtain a cable core assembly; The fireproof and heat-insulating layer 200 is manufactured by coating the outer side of the cable core assembly with a ceramic silicone rubber layer 201 having a thickness of 0.5 mm, laying an aerogel felt layer 202 having a thickness of 0.3 mm on the outer side of the ceramic silicone rubber layer 201, and finally spraying a 0.2 mm thick intumescent fire-resistant coating 203 to form the fireproof and heat-insulating layer 200; The buffer support layer 300 is manufactured as follows: an annular elastic support member 301 having an inner diameter matching the outer diameter of the fireproof and heat-insulating layer 200 is placed over the outer surface of the fireproof and heat-insulating layer 200. The annular elastic support member 301 has a wall thickness of 1 mm and a height of 5 mm, and eight support blocks 302 each 0.5 mm in height are evenly distributed on the inner surface of the annular elastic support member 301. Melamine foam is then filled between the annular elastic support members 301 using a mold at a density of 15 kg / m³ to form the buffer support layer 300. The outer jacket layer 400 is manufactured by heating a low-smoke, halogen-free, flame-retardant polyolefin material to 180°C and melting it. A 1.5mm thick outer jacket layer 400 is then coated around the outside of the buffer support layer 300. A 3mm wide aramid fiber braid 403 is then spirally embedded within the spiral chute 402. A 0.3mm deep anti-slip pattern 405 is then embossed onto the outer jacket layer 400 using a mold. Finished cable testing procedures include: flame retardancy testing of finished cables, including a bundled combustion test in accordance with GB / T18380-2008. The charring height of the cables after combustion should not exceed 2.5 meters. Fire resistance testing is performed in accordance with GB / T19216.21-2003, with a 90-minute flame test at 750°C. The cables must maintain normal signal transmission during the test. Electrical performance testing ensures insulation resistance is no less than 1000MΩ·km, and the conductor's 101D DC resistance meets relevant standards. Mechanical performance testing ensures tensile strength is no less than 50N / mm², and good bending performance is achieved, with no damage or performance degradation after 10 bends. After passing these tests, the cables are packaged and stored.

[0024] Example 2: Differences from Example 1 include eight signal transmission cores 100, nine strands of high-purity oxygen-free copper wire with a diameter of 0.6 mm, twisted together, and a central reinforcement member 104 with a diameter of 2.5 mm. The ceramic silicone rubber layer 201 is 0.6 mm thick, the aerogel felt layer 202 is 0.4 mm thick, and the intumescent fire retardant coating 203 is 0.3 mm thick. The annular elastic support member 301 has a wall thickness of 1.2 mm and a height of 6 mm. The inner support block 302 is 0.6 mm high. The melamine foam filling density is 18 kg / m³. The outer jacket layer 400 is 1.8 mm thick, the aramid fiber braid 403 is 4 mm wide, and the anti-slip pattern 405 is 0.4 mm deep. Production and testing were also conducted in accordance with the aforementioned manufacturing methods and testing standards, and all performance indicators met the requirements.

[0025] Example 3: Differences from Example 1 include the use of ten signal transmission line cores 100, the conductor 101 being 11 strands of high-purity oxygen-free copper wire with a diameter of 0.7 mm, the central reinforcement 104 having a diameter of 3 mm, the ceramic silicone rubber layer 201 having a thickness of 0.7 mm, the aerogel felt layer 202 having a thickness of 0.5 mm, the intumescent fire retardant coating 203 having a thickness of 0.4 mm, the annular elastic support member 301 having a wall thickness of 1.4 mm and a height of 7 mm, the inner support block 302 having a height of 0.7 mm, the melamine foam filling density being 21 kg / m³, the outer jacket 400 having a thickness of 2.1 mm, the aramid fiber braid 403 having a width of 5 mm, and the anti-slip pattern 405 having a depth of 0.5 mm. Production and testing were similarly conducted in accordance with the aforementioned manufacturing methods and testing standards, and all performance indicators met the requirements.

[0026] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. A flame-retardant and fire-resistant shipboard control cable, comprising a cable core assembly, a fireproof and heat-insulating layer (200), a buffer support layer (300) and an outer sheath layer (400), characterized in that: The cable core assembly is composed of a plurality of signal transmission cores (100) and a central reinforcement member (104), wherein the plurality of signal transmission cores (100) are twisted and arranged in a spiral shape around the central reinforcement member (104); The fireproof and heat-insulating layer (200) is coated on the outside of the cable core assembly and adopts a three-layer composite structure design; The buffer support layer (300) is located between the fireproof and heat-insulating layer (200) and the outer sheath layer (400), and is composed of a plurality of annular elastic support members (301) and a buffer material (304) filling the gaps between the annular elastic support members (301); The outer sheath layer (400) is sleeved on the outer surface of the buffer support layer (300), a plurality of spirally distributed longitudinal reinforcing ribs (404) are provided inside the outer sheath layer (400), and a plurality of evenly distributed anti-slip patterns (405) are provided on the outer surface of the outer sheath layer (400).

2. The flame-retardant and fire-resistant shipboard control cable according to claim 1, characterized in that: The signal transmission core (100) is composed of a conductor (101), an insulating layer (102) and a shielding layer (103), wherein the conductor (101) is made of high-purity oxygen-free copper wires twisted together, the insulating layer (102) is made of a polytetrafluoroethylene propylene material with high temperature resistance and excellent flame retardancy, has a uniform thickness, and is tightly coated on the outside of the conductor (101), and the shielding layer (103) is a tinned copper wire braided layer covering the surface of the insulating layer (102).

3. The flame-retardant and fire-resistant shipboard control cable according to claim 2, characterized in that: The central reinforcement (104) is made of glass fiber reinforced plastic rod.

4. The flame-retardant and fire-resistant shipboard control cable according to claim 3, characterized in that: The inner layer of the fireproof and heat-insulating layer (200) is a ceramic silicone rubber layer (201), the middle layer of the fireproof and heat-insulating layer (200) is an aerogel felt layer (202), and the outer layer of the fireproof and heat-insulating layer (200) is an intumescent fireproof coating (203).

5. The flame-retardant and fire-resistant shipboard control cable according to claim 4, characterized in that: The annular elastic support member (301) is made of silicone rubber. A plurality of raised support blocks (302) are provided on the inner side of the annular elastic support member (301), and a plurality of oblique notches (303) are provided on the outer side of the annular elastic support member (301).

6. The flame-retardant and fire-resistant shipboard control cable according to claim 5, characterized in that: The buffer material (304) is melamine foam.

7. The flame-retardant and fire-resistant shipboard control cable according to claim 6, characterized in that: The inner and outer surfaces of the outer sheath layer (400) are coated with a uniformly distributed low-smoke, halogen-free, flame-retardant polyolefin layer (401), and the inner surface of the outer sheath layer (400) is provided with a plurality of spiral chutes (402) distributed in a spiral pattern.

8. The flame-retardant and fire-resistant shipboard control cable according to claim 7, characterized in that: An aramid fiber braided belt (403) is installed inside each spiral chute (402), and each aramid fiber braided belt (403) passes through and is engaged in the corresponding oblique notch (303) in sequence.

9. The flame-retardant and fire-resistant shipboard control cable according to claim 8, characterized in that: The interior of the aramid fiber braided belt (403) is a hollow structure, and the longitudinal reinforcing ribs (404) are adapted to be installed inside the aramid fiber braided belt (403).

10. The method for manufacturing a flame-retardant and fire-resistant shipboard control cable according to claim 9, characterized in that: The following steps are involved: The manufacturing steps of the cable core assembly are as follows: selecting high-purity oxygen-free copper wire with a diameter of 0.5 mm, twisting it into 7 strands to form a conductor (101), the outer diameter of the conductor (101) being 1.2 mm; using an extrusion process to wrap an insulating layer (102) with a thickness of 0.3 mm outside the conductor (101), and then weaving a shielding layer (103) with a coverage rate of 85% outside the insulating layer (102) to form a signal transmission core (100); spirally twisting 6 signal transmission cores (100) around a glass fiber reinforced plastic rod with a diameter of 2 mm, with a twisting pitch of 20 mm, to obtain a cable core assembly; The steps of manufacturing the fireproof and heat-insulating layer (200) are as follows: a ceramic silicone rubber layer (201) with a thickness of 0.5 mm is coated on the outer side of the cable core assembly by a coating process, an aerogel felt layer (202) with a thickness of 0.3 mm is laid outside the ceramic silicone rubber layer (201), and finally an intumescent fireproof coating (203) with a thickness of 0.2 mm is sprayed to form the fireproof and heat-insulating layer (200); The manufacturing steps of the buffer support layer (300) are as follows: an annular elastic support member (301) whose inner diameter matches the outer diameter of the fireproof and heat-insulating layer (200) is placed on the outside of the fireproof and heat-insulating layer (200), the annular elastic support member (301) having a wall thickness of 1 mm and a height of 5 mm, and 8 support blocks (302) with a height of 0.5 mm are evenly distributed on the inner side of the annular elastic support member (301); melamine foam is filled between the annular elastic support members (301) through a mold, with a filling density of 15 kg / m³, to form the buffer support layer (300); The outer sheath layer (400) is manufactured by heating a low-smoke, halogen-free, flame-retardant polyolefin material to 180° C. to melt, and wrapping an outer sheath layer (400) having a thickness of 1.5 mm on the outside of a buffer support layer (300) using a coating process. At the same time, an aramid fiber braid (403) having a width of 3 mm is spirally embedded in a spiral chute (402), and an anti-slip pattern (405) having a depth of 0.3 mm is embossed on the surface of the outer sheath layer (400) using a mold. Finished cable testing procedures include: flame retardancy testing of finished cables, including a standard bundled combustion test. The cable's carbonization height after combustion should not exceed 2.5 meters. Fire resistance testing is also conducted, including a standard 90-minute 750°C flame test. The cable must maintain normal signal transmission during the test. Electrical testing ensures insulation resistance is no less than 1000MΩ·km, and the conductor's DC resistance meets relevant standards. Mechanical testing ensures tensile strength is no less than 50N / mm², and good bending performance is achieved after 10 bends. Cables that pass these tests are then packaged and stored.

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