Photoelectric composite tunnel special cable with high shielding property and rat and ant prevention capability and manufacturing method of photoelectric composite tunnel special cable

Abstract

The invention discloses a photoelectric composite tunnel special cable and a manufacturing method thereof. The photoelectric composite tunnel special cable is suitable for wiring in complex environments such as rail transit and underground pipe galleries. The cable comprises power wire cores, an optical fiber unit, a communication twisted group, a filling structure, a polyolefin lining layer, a galvanized steel tape armor layer and a rat-and-ant-proof modified polyurethane outer sheath. The communication unit adopts a double-polyester-tape wrapping and high-density copper wire braided shielding structure, and the optical fiber unit is provided with a double-layer UV coating and a loose tube package filled with fiber paste. The manufacturing method comprises the steps of conductor twisting, insulation extrusion, optical fiber packaging, communication shielding, cabling, liner and sheath extrusion and armoring processing, and key process parameters are controlled. The cable has good anti-biting, electromagnetic shielding, fireproof and compression-resistant properties.

Description

Technical Field

[0001] The present invention relates to the technical field of cable manufacturing, and in particular to a photoelectric composite special cable suitable for complex laying environments such as tunnels, rail transit and underground pipe galleries, and a manufacturing method thereof. Background Art

[0002] Cables are essential components for power and signal transmission in infrastructure projects such as urban rail transit, highway tunnels, and municipal utility corridors. Underground installations often face challenges such as cramped cabling, high humidity and temperatures, rodent infestation, and electromagnetic interference. These challenges place higher demands on cable systems' safety, long-term stable operation, and maintenance efficiency.

[0003] The common practice in current projects is to adopt a discrete structure in which power cables, communication cables and optical fiber units are laid out separately.

[0004] However, this approach has the following technical limitations:

[0005] (1) The wiring space is large, which is not conducive to intensive use of space;

[0006] (2) The construction process is complicated, there are many connection interfaces, and maintenance operations are inconvenient;

[0007] (3) Due to the dispersed structure, it is difficult to unify the protection capabilities of different types of cables, which can easily cause system failures due to environmental stress or damage by rats and ants.

[0008] To address these issues, the industry has gradually proposed the concept of composite optoelectronic cables, which integrate power transmission, communication cores, and optical fiber signals into a single structure to improve wiring integration and overall protection capabilities. However, existing composite cable products still have shortcomings in the following aspects:

[0009] The shielding layer of some products is only a single braid, which has limited electromagnetic interference suppression capabilities;

[0010] The cable core structure is loose, prone to eccentricity and lateral displacement, resulting in unstable mechanical properties;

[0011] There is a lack of material systems that are adaptable to multiple environments, including pressure resistance, rat and ant resistance, waterproofness, and fire resistance.

[0012] In addition, the complexity of the composite structure places higher demands on the production process, such as: wire core twisting accuracy, shielding density control, sheath material modification and cooling section temperature control, which directly affect the consistency of cable performance and product quality stability.

[0013] Therefore, there is an urgent need to propose a photoelectric composite tunnel special cable and its manufacturing method with high integration, high shielding, strong anti-rat and ant ability, excellent mechanical protection performance and scalable manufacturing, so as to meet the functional requirements and operational reliability requirements of the integrated transmission cable in the complex underground space environment. Summary of the Invention

[0014] The present invention aims to solve the problems of existing tunnel cables, such as structural dispersion, insufficient protection performance, low integration and poor environmental adaptability, and provide an optoelectronic composite tunnel special cable with a compact structure, high integration, strong protection capability and industrial production, and a manufacturing method thereof, to meet the stringent requirements of complex underground spaces such as urban rail transit and integrated pipeline corridors for high-reliability transmission systems.

[0015] To achieve the above goals, the present invention adopts the strategy of "module integration + partition protection + full-process controllable manufacturing" and optimizes the system from aspects such as structural layout, shielding performance, sheath material and production process:

[0016] In terms of structural integration: the power line core, communication twisted group, optical fiber unit and filling structure are synchronously twisted together to construct a composite cable core in a pitch-diameter ratio controlled manner. The three types of functional units are uniformly arranged in the same structure to improve space utilization and project deployment efficiency.

[0017] In terms of shielding performance: the communication twisted group adopts a composite shielding structure of "twisted conductor + double polyester tape + high-density copper wire braiding", with a shielding suppression coefficient of 0.002, which is significantly better than the TICW 6 standard requirements and has excellent electromagnetic anti-interference ability.

[0018] In terms of protection capability: the outer protective layer adopts rat- and ant-proof modified low-smoke halogen-free polyurethane material, which complies with industry standards such as JB / T10696.10 and JB / T 10696.9, and has comprehensive advantages in terms of rodent resistance, thermal aging, and wear resistance.

[0019] In terms of manufacturing controllability: detailed specifications are formulated for the process parameters of each process (such as conductor pitch ratio, extrusion temperature control zone, braiding density, cooling section temperature difference control, etc.), ensuring the consistency of the cable manufacturing process and the long-term stability of the cable structure.

[0020] The cable structure from the inside out is as follows:

[0021] Power line core: a conductor made of multiple copper filaments twisted together and covered with a cross-linked polyethylene (XLPE) insulation layer;

[0022] Optical fiber unit: The optical fiber core surface is provided with a double-layer UV curing coating, the outer surface is filled with fiber paste and encapsulated in a PBT loose tube;

[0023] Communication twisted group: It is composed of two cross-linked polyethylene insulated wire cores twisted into a pair, covered with polyester tape + copper wire braid + polyester tape to form a composite shielding module;

[0024] Cable core structure: The above functional units and filling ropes are twisted together to form a cable core, which is then wrapped with flame retardant tape and inner lining layer;

[0025] Armor and sheath layer: The outside is equipped with double-layer galvanized steel belt armor layer and anti-rat and ant modified polyurethane sheath.

[0026] The present invention also provides a method for manufacturing the above-mentioned structural cable, comprising the following steps:

[0027] Copper monofilament drawing and conductor bundle stranding (pitch diameter ratio 21-26);

[0028] Extrusion of cross-linked polyethylene insulation layer (five-stage temperature control to 230℃ at the die head, staged cooling);

[0029] Communication wire cores are twisted in pairs, double-layer polyester wrapping, copper wire braid shielding (density ≥ 80%, regular wiring);

[0030] Fiber prefabrication, double-layer UV coating, fiber jelly injection, loose tube packaging and heat shrink sealing;

[0031] Cabling: Power line core, communication group, optical fiber and filling rope are twisted synchronously with a pitch diameter ratio of 18 to 22;

[0032] Liner layer extrusion (temperature control zone 166~209℃);

[0033] Double-layer steel tape spiral armor (gap ≤ 50% of the bandwidth, cut at a 45° angle);

[0034] The outer protective layer is extruded (temperature control zone 165 ~ 235 ℃), and the cooling water tank is temperature controlled in sections to prevent moisture absorption;

[0035] Cable inspection, winding and storage.

[0036] The measured results show that the optoelectronic composite tunnel special cable described in the present invention is significantly superior to existing industry products in key performance indicators such as rodent and ant resistance, shielding suppression, waterproof and compressive resistance, thermal aging, and mechanical strength, and has a good industrial manufacturing foundation and adaptability to complex environments.

[0037] The present invention is suitable for scenarios such as urban rail transit, smart pipeline corridors, power and communication integrated systems, and data center channels. It can effectively solve engineering pain points such as rat and ant gnawing, electromagnetic interference, limited laying space, and insufficient durability, and achieve long-term reliable operation of the integrated wiring system for power supply, communication, and monitoring. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] To more clearly illustrate the technical solution of the present invention, the structural composition and manufacturing process of the embodiment are now described in conjunction with the accompanying drawings. The accompanying drawings only show preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention.

[0039] Figure 1 This is a schematic diagram of the overall structure of the special cable of the present invention;

[0040] Figure 2 is a cross-sectional structural diagram of the optical fiber unit of the present invention;

[0041] Figure 3 is a schematic diagram of the cross-sectional structure of the communication twisted group of the present invention;

[0042] Figure 4 It is a manufacturing process flow chart of the special cable described in the present invention.

[0043] Description of Reference Numerals

[0044] Figure 1 :

[0045] 1—Power line core

[0046] 2—Fiber optic unit

[0047] 3—Communication twisted group

[0048] 4—Cable core

[0049] 5—Inner lining

[0050] 6—Armor layer

[0051] 7—Outer sheath

[0052] 8—Filling rope

[0053] Figure 2 :

[0054] 2a—Fiber core

[0055] 2b—One coat

[0056] 2c—Secondary coating

[0057] 2d—Fiber paste filling layer

[0058] 2e—Loose tube

[0059] Figure 3 :

[0060] 3a—Conductor

[0061] 3b—cross-linked polyethylene insulation layer

[0062] 3c—First polyester tape wrapping layer

[0063] 3d—copper wire braided shield

[0064] 3e—Second polyester tape wrapping layer

[0065] Figure 4 :

[0066] A—Conductor Preparation

[0067] B—Insulation extrusion

[0068] C—Fiber Prefabrication and Coating

[0069] D—Twisting and shielding of communication core

[0070] E—cabled

[0071] F—Inner liner extrusion

[0072] G—Steel belt armor

[0073] H—Extrusion of outer sheath

[0074] I—Inspection and Rewinding

[0075] J—Packaging DETAILED DESCRIPTION

[0076] In order to make the technical solution of the present invention more clear, the present invention is described in detail below with reference to the accompanying drawings and embodiments. However, it should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of protection of the present invention.

[0077] Example 1: Cable Structure

[0078] This embodiment provides a structural solution for a photoelectric composite special cable with high integration, high shielding and rat and ant resistance, and is suitable for the integrated installation of power and communications in complex tunnel environments.

[0079] Power line core (label 1):

[0080] This conductor is constructed from multiple strands of copper monofilaments, with diameters ranging from 0.54mm to 2.22mm. The overall conductor diameter ranges from 1.6mm to 6.0mm. The conductor is twisted in a left-hand configuration, with a pitch-to-diameter ratio of 21 to 26. The conductor is covered with a cross-linked polyethylene (XLPE) insulation layer with a thickness of 1.0 to 1.2mm, with the thinnest point no less than 90% of the nominal value minus 0.1mm, to ensure insulation strength and thickness uniformity.

[0081] Optical fiber unit (label 2):

[0082] An optical fiber core with a diameter of 125±1μm is coated with a double layer of UV-curable coating. The first layer is a low-modulus acrylic resin with a thickness of 30-50μm; the second layer is a high-modulus UV resin with a thickness of 20-40μm, forming a flexible-rigid composite protective structure. After coating, a viscoelastic and sealing fiber paste is injected and encapsulated in a polybutylene terephthalate (PBT) loose tube. Heat shrink seals are used at both ends (sealing temperature 120-150°C) to enhance the waterproof and shockproof properties of the entire optical fiber unit.

[0083] Communication twisted group (label 3):

[0084] The communication unit consists of two twisted pairs of communication wire cores, each using a 0.19-0.24mm copper monofilament bundled conductor. The overall conductor diameter is 0.9-2.1mm, the bundled pitch-to-diameter ratio is controlled at 20-25, and the twisted pitch-to-diameter ratio is no more than 8. The conductor is covered with a cross-linked polyethylene insulation layer (thickness 0.6-0.8mm), which is then wrapped with a first layer of polyester tape, a copper wire braided shield (copper wire diameter 0.10-0.15mm, braiding density ≥80%), and a second layer of polyester tape, forming a high-shielding composite structure that effectively suppresses high-frequency interference.

[0085] Cable core and filling structure (number 4 and 8):

[0086] The cable core is formed by twisting the aforementioned power line core, optical fiber unit, and communication stranded group together with a filler rope (labeled 8) made of flame-retardant polypropylene mesh film. The twisting pitch ratio is controlled between 18 and 22 to ensure structural compactness and roundness. The cable core is wrapped with a 0.1mm thick low-smoke, halogen-free flame-retardant tape with an overlap width of at least 5mm, providing excellent flame retardancy and mechanical stability.

[0087] Lining layer (No. 5):

[0088] It is extruded from polyolefin material with a thickness controlled at 0.8-1.0mm and the thickness at the thinnest point not less than 80% of the nominal value. It is used to provide a structural transition and water vapor barrier between the cable core and the outer structure.

[0089] Armor layer (No. 6):

[0090] The exterior is equipped with a double-layer, left-hand spirally wrapped galvanized steel belt. The thickness of each layer is 0.2mm, and the gap between the wraps is no more than 50% of the belt width. This structure significantly enhances the cable's compression resistance, resistance to rat and ant bites, and tolerance to external impact.

[0091] Outer sheath (No. 7):

[0092] The sheath is extruded from rat- and ant-proof modified low-smoke halogen-free flame-retardant polyurethane material with a thickness of 0.9 to 1.8 mm, and the thinnest point is not less than 80% of the nominal value - 0.2 mm. It has excellent anti-bite, anti-wear and weather resistance.

[0093] The structure described in this embodiment has a compact layout and reasonable material matching. It has significant advantages such as strong electromagnetic interference suppression capability, high resistance to mechanical damage, and excellent comprehensive waterproof and anti-termite performance. It is suitable for complex laying environments such as various underground projects, rail transit and intelligent pipeline corridors.

[0094] Example 2: Description of manufacturing process parameters

[0095] To achieve the high-performance integrated characteristics of the cable structure of the present invention, this embodiment provides a complete manufacturing process flow and process parameters, as follows:

[0096] Step 1: Conductor Manufacturing: A copper rod is drawn into a single wire using a wire drawing die. The wire passes through 11 drawing dies, controlling the copper wire diameter within the range of 0.54mm to 2.22mm. The wire is then twisted into multiple strands with a pitch-to-diameter ratio of 21 to 26 to ensure conductor flexibility and structural stability.

[0097] Step 2: Insulation extrusion: A cross-linked polyethylene (XLPE) insulation layer is extruded on the outside of the conductor. The temperature control parameters are as follows: Zone 1 140-160°C, Zone 2 150-190°C, Zone 3 190-200°C, Zone 4 200-220°C, Zone 5 220-230°C, and the die head temperature is 250°C; the conductor preheating temperature is controlled at 70±10°C, the line speed is 45-60m / min, the screw speed is 35-50r / min, and the cooling water temperature is maintained in the range of 40-60°C.

[0098] Step 3: Processing the Communication Twisting Group: The communication cable cores are twisted on a tubular stranding machine, with a pitch-to-diameter ratio of no more than 8. The first layer of 0.04mm polyester tape is then wrapped around the strands. The copper wires are braided tightly and without cross-linking, with a braid density of no less than 80%. The copper wire strands are replaced once every meter. Finally, a layer of 0.04mm polyester tape is applied to the strands to complete the composite shielding structure.

[0099] Step 4: Fiber encapsulation: The fiber core is prefabricated using modified chemical vapor deposition (MCVD) with a diameter of 125±1μm. It is then double-layered with UV coating, where the primary coating thickness is 30-50μm and the secondary coating thickness is 20-40μm. The UV intensity is no less than 1000mW / cm 2 After filling the outside with fiber paste, insert the optical fiber core into the PBT loose tube, let it stand for 10 to 30 minutes to set, and then seal it by heat shrink sealing (sealing temperature range 120 to 150℃).

[0100] Step 5: Cabling and Flame-Retardant Tape Coating: The power line core, optical fiber unit, communication stranded group, and filler rope are twisted synchronously at a pitch-to-diameter ratio of 18 to 22 to form the cable core structure. An outer layer of 0.2mm thick low-smoke, halogen-free flame-retardant tape is wrapped, with an overlap width of at least 5mm, to ensure a compact cable core with primary flame-retardant properties.

[0101] Step 6: The inner lining layer is extruded with polyolefin material, and the temperature control settings are as follows: Zone 1 166°C, Zone 2 177°C, Zone 3 197°C, Zone 4 195°C, Zone 5 198°C, Zone 6 200°C, and the temperature of the machine neck and head is 206-209°C; the cooling method uses a two-section water tank, the water temperature of the first section is 40-60°C, and the second section is natural cooling at room temperature.

[0102] Step 7: For armoring, use 0.2mm thick galvanized steel strips for double-layer left-hand spiral wrapping, with the wrapping gap not exceeding 50% of the strip width. The steel strips are cut at a 45° angle, ensuring a clean, burr-free, and rust-free interface, enhancing overall compressive protection.

[0103] Step 8: For the outer sheath, a rat- and ant-resistant, modified, low-smoke, halogen-free, flame-retardant polyurethane material is used. The extrusion temperature is controlled as follows: Zone 1: 165-185°C, Zone 2: 185-205°C, Zone 3: 195-225°C, Zone 4: 200-230°C, Zone 5: 205-235°C, and the die head temperature is 230°C. The cooling water tank is a two-stage system: the first stage is kept at 60-80°C, and the second is at room temperature to prevent water ingress and thermal shock.

[0104] Through the above-mentioned optimized process configuration, the optoelectronic composite special cable of the present invention can achieve continuous industrial manufacturing while ensuring structural compactness and high reliability, and is suitable for long-term laying applications in complex environments.

[0105] Example 3: Third-party performance testing verification

[0106] To verify the comprehensive performance of the cable of the present invention in terms of anti-biological corrosion, environmental safety, and electromagnetic interference suppression, the applicant organized targeted tests on relevant performance. The specific results are as follows:

[0107] In terms of rat and ant resistance: a rat resistance test was carried out in accordance with JB / T 10696.10 standard, using a simulated biting device for continuous biting for 30 days. The cable sheath maintained structural integrity, and the measured protection rate was 0.7, meeting the standard's requirements for first-level protection. The termite resistance was carried out in accordance with JB / T 10696.9 and the "colony method" in the "Technical Specifications for Pipelines". After the test, the cable sample had no perforations and was rated level 1 (≤ level 2 is the qualified standard), indicating that the structure and sheath material of the present invention have excellent resistance to biological damage.

[0108] Environmental performance: After testing, the halogen content of the cable sheath and insulation materials complies with the requirements of GB / T 19666, with the chlorine / bromine content not exceeding 0.5% and the fluorine content not exceeding 0.1%. The actual measured results show a chlorine / bromine content of 0.2% and a fluorine content of 0.01%, which belongs to a low-halogen environmental protection system and meets the requirements of scenarios that are highly sensitive to environmental protection and passenger safety, such as rail transit and data centers.

[0109] In terms of smoke density and flame retardant performance: the luminous flux transmittance test was carried out according to the IEC 61034-2 standard, and the measured transmittance was 72%, which is higher than the judgment index of ≥60%, indicating that the smoke density is low during the combustion process, which is conducive to emergency evacuation and fire identification.

[0110] In terms of electromagnetic interference suppression: the communication twisted group adopts a composite shielding structure (double-layer polyester tape + high-density copper wire braiding), and the shielding suppression coefficient test is carried out according to the TICW 6 standard. The measured value is 0.002, which is far lower than the industry indicator ≤0.01. This shows that the structure of the present invention has extremely strong electromagnetic suppression capabilities in high-frequency interference scenarios and is suitable for intelligent transportation systems and data control link deployment.

[0111] In summary, the cable of the present invention has excellent performance in terms of rat and ant resistance, environmental protection and halogen-free, low smoke flame retardancy and shielding and anti-interference capabilities, and meets the application requirements of underground engineering, rail transportation, data communication, etc. with high requirements on safety and system stability.

[0112] Example 4: Comprehensive performance test

[0113] In order to verify the comprehensive performance of the optoelectronic composite special cable of the present invention in terms of electrical, mechanical and environmental adaptability, the applicant organized a systematic test on a standard batch of products. The test items were carried out in accordance with GB / T 12706, GB / T 3048, GB / T2951 and IEC 60811 standards. The results are as follows:

[0114] In terms of electrical performance: the DC resistance of the power core complies with the provisions of GB / T 3048, and the actual measured value is 1.13Ω / km, indicating good conductor transmission efficiency; the AC withstand voltage test remains at 3.5kV for 5 minutes without breakdown, meeting the basic electrical strength requirements of tunnel cables; in the high-temperature insulation resistance test, the actual measured value is 21.3MΩ·km, which is higher than the standard requirement of 20MΩ·km.

[0115] In terms of structural dimensions: the average outer diameter of the cable is 15.0mm, the average thickness of the outer sheath is 1.5mm, and the thickness is maintained at more than 90% of the nominal value, reflecting structural consistency; the cable core is well formed, the twist direction is correct, the pitch is uniform, there is no yarn skipping phenomenon, and the structure is stable; the surface of the outer sheath is free of cracks, bubbles, scratches or impurities, meeting the sealing and mechanical strength requirements of the underground laying environment.

[0116] In terms of material mechanical properties: the tensile strength of the insulation layer reaches 22.7MPa (standard ≥15MPa), and the elongation at break is ≥300% (standard ≥150%); after aging, the tensile strength is maintained at 19.5MPa (more than 85% of the original value), and the elongation at break is maintained at ≥250% (about 90% of the original value), reflecting excellent heat aging resistance.

[0117] In terms of stability: When the finished cable is powered on, the temperature rise is well controlled and no abnormal interference is detected, indicating that it has thermal stability and electromagnetic stability under high-load operation.

[0118] The above experimental results show that the cable of the present invention meets or exceeds the national and industry standards in key performance indicators, has good electrical safety, mechanical strength and manufacturing consistency, and is suitable for engineering application scenarios with long-term service and high reliability requirements.

[0119] Example 5: Engineering Application Adaptability Analysis

[0120] This embodiment verifies the application effect of the cable of the present invention in typical underground space projects, including urban subways, high-speed railway electrical pipeline corridors, smart data centers, etc.

[0121] Subway scenario: high requirements for line interference. After actual measurement, the communication bit error rate dropped by more than 80% after using this cable, avoiding EMI interference;

[0122] High-speed rail communication channel: The cable laying space is narrow and the alternation of heat and humidity is intense, which verifies that the sheath has excellent anti-bite and anti-thermal deformation performance;

[0123] Smart data center: has high requirements for fire retardancy and environmental protection. The low-smoke halogen-free sheath of this cable meets the LEED Gold standard and has been used in many demonstration projects.

[0124] The above embodiments further illustrate that the present invention has broad engineering adaptability and promotion value, and is particularly suitable for critical scenarios with high requirements for electromagnetic shielding, safety and environmental protection.

Claims

1. A photoelectric composite special cable, characterized in that: include: A power line core, comprising a conductor formed by twisting multiple copper monofilaments and a cross-linked polyethylene insulation layer covering the conductor; An optical fiber unit, comprising an optical fiber core having a double-layer UV-cured coating, the optical fiber core being externally filled with fiber paste and encapsulated in a loose tube; A communication twisted group, the communication twisted group includes at least two communication wire cores twisted together, the communication wire core includes a conductor formed by bundling copper monofilaments and a cross-linked polyethylene insulation layer on the outside, and the outside of the communication twisted group is sequentially provided with a first polyester tape wrapping layer, a copper wire braided shielding layer and a second polyester tape wrapping layer; a cable core, the cable core is formed by twisting the power line core, the optical fiber unit, the communication twisted group and the filling rope, and is wound with a flame retardant tape on the outside; an inner lining layer, the inner lining layer is formed by extrusion of a polyolefin material; an armor layer, the armor layer is a double-layer galvanized steel tape spirally wrapped structure; an outer sheath, the outer sheath is formed by extrusion of a rat- and ant-proof modified low-smoke halogen-free flame-retardant polyurethane material.

2. The cable according to claim 1, wherein: The twisted pitch ratio of the power line core is 21-26, and the thickness of the insulation layer is 1.0-1.2 mm.

3. The cable according to claim 1, wherein: The optical fiber core diameter is 125±1 μm, the thickness of the primary UV coating is 30-50 μm, and the thickness of the secondary UV coating is 20-40 μm.

4. The cable according to claim 1, wherein: The copper wire braiding density of the shielding layer of the communication twisted group is not less than 80%, and the shielding suppression coefficient is lower than 0.

002.

5. The cable according to claim 1, characterized in that: The cable core twisted pitch-diameter ratio is 18-22, the thickness of the flame retardant tape is 0.1 mm, and the wrapping overlap width is not less than 5 mm.

6. The cable according to claim 1, characterized in that: The thickness of the inner lining layer is 0.8-1.0 mm, and the thickness at the thinnest point is not less than 80% of the nominal value.

7. The cable according to claim 1, characterized in that: The thickness of the outer protective layer is 0.9-1.8 mm, and the thickness at the thinnest point is not less than 80% of the nominal value minus 0.2 mm.

8. A method for manufacturing the cable according to claim 1, characterized in that: The invention comprises the following steps: (1) preparing a power line core: twisting copper monofilaments into a conductor, and coating the conductor with a cross-linked polyethylene insulation layer, wherein the temperature control range is 140-230°C, and adopting segmented cooling; (2) preparing a communication twisted group: twisting the communication line cores, and then wrapping them with a first polyester tape, a copper wire braided shielding layer, and a second polyester tape in sequence; (3) preparing an optical fiber unit: applying a double-layer UV coating to the optical fiber core, filling it with fiber paste, and then encapsulating it in a loose tube and sealing it; (4) cabling: twisting the power line core, the communication twisted group, the optical fiber unit, and the filling rope, and wrapping them with a flame retardant tape to form a cable core; (5) extruding an inner lining layer: extruding a polyolefin material to form an inner lining layer; (6) armoring processing: spirally wrapping a double-layer galvanized steel tape to form an armor layer; (7) extruding an outer sheath: extruding a rat-ant-proof modified low-smoke halogen-free polyurethane material to form an outer sheath, and cooling and shaping it.

9. The method according to claim 8, characterized in that: The loose tube is sealed by heat shrinkage or mechanical compression.

10. The method according to claim 8, characterized in that: The extrusion temperature control range of the outer protective layer is preferably 165-235°C, and the cooling water temperature is preferably controlled at 40-60°C.

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