High-strength submarine high-voltage photoelectric composite cable

Abstract

The invention discloses a high-strength submarine high-voltage photoelectric composite cable, and belongs to the technical field of photoelectric composite cable production, firstly, the photoelectric composite cable comprises an optical fiber unit, an electromagnetic shielding-compression-resistant layer, a power conductor layer, a non-metal composite armor layer and an outer sheath layer which are sequentially arranged from inside to outside; wherein the optical fiber unit is formed by pre-stretching an optical fiber, embedding the pre-stretched optical fiber into a polyether-ether-ketone spiral skeleton, and filling and fixing the pre-stretched optical fiber with silica gel; the electromagnetic shielding-compressive layer comprises outer conductive graphene polyethylene and inner foamed silicone rubber; the power conductor layer is formed by wrapping annealed copper stranded wires with crosslinked polyethylene; the non-metal composite armor layer is formed by impregnating a basalt fiber woven belt with modified epoxy resin; and the outer sheath layer is prepared by mixing high-density polyethylene with silicon carbide nanoparticles. Through structural design and material combination, the problem of optical signal loss caused by metal armoring corrosion, electromagnetic interference and sheath high-pressure deformation of a traditional submarine photoelectric composite cable is solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of submarine cables, and particularly relates to a high-strength composite cable applicable to deep-sea environments (water depth ≥ 3000 meters), integrating high-voltage power transmission (10 - 220 kV), optical signal communication (single-mode optical fiber, wavelength 1550 nm), corrosion resistance, and anti-mechanical impact functions, and is applicable to scenarios such as transoceanic communication, power supply for undersea oil and gas fields, and ocean observation networks. Background Art

[0002] Deep-sea engineering has extremely high requirements for the reliability of composite cables. Taking a deep-sea oil and gas field in the South China Sea as an example, its power supply system needs to transmit 220 kV high-voltage electricity through submarine cables and simultaneously transmit real-time monitoring data (bandwidth ≥ 10 Gbps). Existing composite cables need to withstand ocean current impacts (flow velocity ≥ 3 m / s), deep-sea high pressures (≥ 30 MPa), and sulfide corrosion within a 30-year life cycle, and also need to avoid biological damage such as shark bites. According to industry statistics, the annual economic loss caused by submarine cable failures globally exceeds 1.5 billion US dollars, and 60% of which is caused by mechanical damage and corrosion.

[0003] Traditional composite cables adopt a structure of galvanized steel wire armor + polyethylene sheath + copper conductor, and have the following defects: (1) Metal armor corrosion: Under the erosion of seawater Cl - ions, the annual corrosion rate is ≥ 0.1 mm, resulting in a 35% decrease in tensile strength after 5 years (from the initial 500 MPa to 325 MPa); (2) Electromagnetic interference: The electromagnetic coupling effect between the metal armor and the copper conductor increases the bit error rate (BER) of optical signals to 10 -6 , exceeding the tolerance of submarine repeaters (requiring BER ≤ 10 -9 ); (3) Sheath deformation: Under deep-sea high pressure, the compression deformation of the polyethylene sheath is ≥ 2%, resulting in an increase in the micro-bending loss of optical fibers to 0.15 dB / km (the standard requirement is ≤ 0.05 dB / km).

[0004] The existing technology cannot meet the long-term stability requirements of deep-sea engineering. Therefore, there is an urgent need to develop a composite cable with non-metallic armor, excellent compressive and bending resistance, and electromagnetic shielding performance to reduce the full-life cycle cost and improve the reliability of data transmission. Summary of the Invention

[0005] The purpose of the present invention is to provide a high-strength submarine high-voltage optical and electrical composite cable to solve the problems of optical signal loss caused by metal armor corrosion, electromagnetic interference, and high-voltage deformation of the sheath, and at the same time improve the tensile strength and fatigue life.

[0006] The purpose of the present invention can be achieved through the following technical solutions: A high-strength submarine high-voltage optical power composite cable, comprising an optical fiber unit, an electromagnetic shielding - compressive layer, a power conductor layer, a non-metallic composite armor layer, and an outer sheath layer, which are arranged in sequence from the inside to the outside; The optical fiber unit is formed by pre-stretching an optical fiber and embedding it into a polyether ether ketone spiral skeleton, and filling and fixing it with silicone gel; The electromagnetic shielding - compressive layer includes an outer layer of conductive graphene polyethylene and an inner layer of foamed silicone rubber; The power conductor layer is composed of cross-linked polyethylene-coated annealed copper stranded wires; The non-metallic composite armor layer is made of basalt fiber braided tape impregnated with modified epoxy resin; The outer sheath layer is made of high-density polyethylene blended with 3wt% silicon carbide nanoparticles.

[0007] Further, the spiral angle of the polyether ether ketone spiral skeleton is 30°, the pitch is 50mm, the outer diameter is 6mm, and 24 grooves are provided inside; the optical fiber is embedded in the grooves in a pre-stretched state of 0.05% - 0.15%.

[0008] Further, the Shore A hardness of the silicone gel is 30, and the viscosity is 5000cP.

[0009] Further, the thickness of the outer layer of conductive graphene polyethylene is 2mm; the inner layer of foamed silicone rubber has a thickness of 4mm, and the density of the foamed silicone rubber is 0.5 - 0.7g / cm 3 .

[0010] Further, the conductive graphene polyethylene is prepared by the following steps: First, the conductive graphene polyethylene includes the following raw materials in parts by mass: 100 parts of high-density polyethylene, 3 - 7 parts of graphene, and 1 part of silane coupling agent KH-550; Then, weigh each raw material according to the parts by mass, mix graphene and KH-550 in proportion, add absolute ethanol according to a solid-liquid ratio of 1:20, ultrasonically disperse for 30min, dry at 60°C to remove the solvent to obtain pretreated graphene, and then add the pretreated graphene and high-density polyethylene into a twin-screw extruder to extrude and granulate. After completion, obtain pellets, inject the pellets into a mold, press at 170 - 185°C to form a 2mm thick sheet, cool and cut to obtain conductive graphene polyethylene.

[0011] Further, the foamed silicone rubber is prepared by the following steps: First, the foamed silicone rubber includes the following raw materials in parts by mass: 100 parts of methyl vinyl silicone rubber, 4 - 5 parts of azodicarbonamide, and 1 - 2 parts of bis(2,5-dimethyl-2,5-di(t-butylperoxy)hexane); Then, weigh each raw material by parts by mass. Plasticate methyl vinyl silicone rubber on an open mill for 5 min, add azodicarbonamide and bis(2,5-dimethyl-2,5-di(tert-butylperoxy)hexane) vulcanizing agent, and mix for 10 min until uniform to obtain a rubber compound. Place the rubber compound into a mold and cure it in two stages on a flat vulcanizer: The first stage: 160 °C × 5 min; The second stage: 170 °C × 10 min. After curing, demold and then place it in an oven at 120 °C for 2 h to obtain foamed silicone rubber.

[0012] Further, the monofilament diameter of the basalt fiber braided tape is 0.2 mm, and the tensile strength is 2800 MPa.

[0013] Further, the modified epoxy resin contains 3 wt% nano-silica.

[0014] Further, the thickness of the outer sheath layer is 5 mm.

[0015] Advantages of the present invention: Through structural design and material combination, the present invention solves the problems of metal armor corrosion, electromagnetic interference and optical signal loss caused by high-voltage deformation of the sheath existing in traditional submarine optical composite cables, and at the same time improves the tensile strength and fatigue life. The following combines specific test data to elaborate on the advantages of the present invention in detail: (1) The non-metallic composite armor layer solves the corrosion problem, and the tensile strength retention rate is increased by 50%: For the traditional galvanized steel wire armor (Comparative Example 1), the tensile strength decreased from the initial 500 MPa to 325 MPa (a decrease of 35%) after 5000 h of salt spray, while the present invention uses a basalt fiber braided tape impregnated with modified epoxy resin (Example 2), and the tensile strength retention rate after 5000 h of salt spray is as high as 95% (497 MPa / 518 MPa). The data comparison proves that: the non-metallic armor layer, through the high strength of basalt fiber (2800 MPa) and the Cl - penetration resistance of nano-silica modified epoxy resin, completely solves the problem of strength attenuation caused by metal corrosion and meets the long-term service requirements of deep-sea engineering.

[0016] (2) The electromagnetic shielding - compressive layer is designed in a coordinated manner, and the optical signal loss is reduced by 85%: Under a deep-sea pressure of 30 MPa, the optical signal loss of Example 2 only increases by 0.021 dB / km (from 0.198 dB / km to 0.219 dB / km), while the losses of Comparative Example 2 (ordinary PE lining) and Comparative Example 3 (solid silicone rubber) reach 0.286 dB / km and 0.261 dB / km respectively. The key mechanism: Conductive graphene polyethylene (7 wt% graphene): forms a continuous conductive network, and the shielding effectiveness reaches 42 dB (only 18 dB for Comparative Example 2), and the bit error rate decreases from 10 -6Reduce to 10 -10 , meeting the requirements of the subsea repeater; Foamed silicone rubber: Absorbs pressure through pore collapse to avoid microbending of the optical fiber (in Comparative Example 3, due to insufficient deformation buffering of solid silicone rubber, the loss increased by 24%).

[0017] (3) Pre-tensioned optical fiber and PEEK skeleton design, with the compressive deformation performance increased by 3 times: In Example 2, the optical fiber was embedded in the PEEK spiral skeleton (spiral angle 30°) in a pre-tensioned state of 0.1%, and filled with silicone gel (Shore A 30), so that the increase in optical fiber loss under 30 MPa pressure was ≤0.02 dB / km. Comparative verification: The loss of the traditional structure (without pre-tension + straight skeleton) reached 0.15 dB / km under the same pressure, while the present invention offset the compressive strain through pre-tension and dispersed the stress by combining the spiral skeleton, reducing the loss by 87%; in Comparative Example 3 (solid silicone rubber), due to the lack of deformation buffering of the foamed structure, the loss was 19% higher than that of Example 2 (0.261 dB / km vs 0.219 dB / km).

[0018] (4) Fatigue life increased to 3 times that of the traditional one, and the full life cycle cost reduced by 60%: In the simulated ocean current impact test, the fatigue life of Example 2 reached 1.2×10 7 cycles, significantly higher than that of Comparative Example 1 (4×10 6 cycles) and Comparative Example 3 (6×10 6 cycles). The core reasons are: Energy absorption by foamed silicone rubber: The closed-cell structure dissipates energy through pore compression - rebound under cyclic loading, delaying crack propagation; Conclusion: Through the collaborative innovation of the non-metallic armor layer, electromagnetic shielding - compressive lining, and pre-tensioned optical fiber structure, the present invention has achieved significant improvements in corrosion resistance (strength retention rate ≥95% after 5000 h of salt spray), low signal loss (≤0.02 dB / km under 30 MPa), high shielding efficiency (42 dB), and long fatigue life (1.2×10 7 cycles). This composite cable can meet the deep-sea engineering requirements with a water depth ≥3000 meters and a service life ≥25 years. Specific embodiments

[0019] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in combination with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts fall within the protection scope of the present invention. The raw materials, reagents, or devices used in the following embodiments can be obtained from conventional commercial channels or can be obtained by existing known methods without special instructions.

[0020] Example 1

[0021] A high-strength submarine high-voltage optoelectronic composite cable, comprising, from inside to outside in sequence, an optical fiber unit, an electromagnetic shielding and pressure-resistant layer, a power conductor layer, a non-metallic composite armor layer, and an outer sheath layer: (1) The structure and functions of the optical fiber unit are as follows: Spiral skeleton: Made of polyetheretherketone (PEEK) material, with a spiral angle of 30°, a pitch of 50 mm, an outer diameter of 6 mm, and 24 grooves (single groove diameter 0.25 mm) provided inside.

[0022] Optical fiber arrangement: G.652.D single-mode optical fibers are embedded in the above grooves in a pre-stretched state of 0.05% to eliminate installation stress.

[0023] Filling material: Silicone gel (Shore A hardness 30, viscosity 5000 cP), filling the gap to buffer external pressure, and forming a flexible support layer after curing.

[0024] Function: Inhibit micro-bending loss caused by deep-sea high pressure.

[0025] (2) The structure, process and functions of the electromagnetic shielding and pressure-resistant layer are as follows: Outer layer (shielding layer): Conductive graphene polyethylene, with a thickness of 2 mm.

[0026] Inner layer (pressure-resistant layer): Foamed silicone rubber, with a thickness of 4 mm and a density of 0.5 g / cm 3 .

[0027] Process: Double-layer co-extrusion molding (temperature 185°C) to ensure tight bonding between layers.

[0028] Function: Block electromagnetic interference of the power conductor, absorb deformation of deep-sea pressure, and protect the optical fiber unit.

[0029] Among them, the conductive graphene polyethylene is prepared by the following steps: Raw materials: 100 parts (by mass) of high-density polyethylene (HDPE, melt index 0.5 g / 10 min), 3 parts (by mass) of graphene, 1 part (by mass) of silane coupling agent KH-550.

[0030] Preparation steps: Weigh each raw material by mass parts. Mix graphene with KH-550 in proportion, add absolute ethanol (solid-liquid ratio 1:20), disperse ultrasonically for 30 min (power 300 W), dry at 60 °C to remove the solvent, and obtain pretreated graphene. Then add the pretreated graphene and high-density polyethylene into a twin-screw extruder (length-diameter ratio 40:1), set the temperature zones: Zone 1: 150 °C (to prevent premature melting of PE); Zone 2: 170 °C (for melting and mixing); Zone 3: 185 °C (for uniform dispersion); screw rotation speed 200 rpm, residence time 3 min, extrude and pelletize. After completion, obtain pellets. Inject the pellets into a mold, press at 170 °C to form a 2-mm thick sheet, cut after cooling, and obtain conductive graphene polyethylene.

[0031] Among them, the foamed silicone rubber is prepared by the following steps: Raw materials: 100 parts (by mass) of methyl vinyl silicone rubber (VMQ, hardness Shore A 30), 4 parts (by mass) of azodicarbonamide (decomposition temperature 160 °C), 1 part (by mass) of bis(2,5-dimethyl-2,5-di(tert-butylperoxy)hexane) curing agent.

[0032] Preparation steps: Weigh each raw material by mass parts. Plasticize the methyl vinyl silicone rubber on an open mill for 5 min (roll temperature 50 °C), add azodicarbonamide and bis(2,5-dimethyl-2,5-di(tert-butylperoxy)hexane) curing agent, knead for 10 min until uniform to obtain a rubber compound. Put the rubber compound into a mold and cure in a flat vulcanizer in two stages: The first stage: 160 °C × 5 min (the blowing agent decomposes to generate gas to form closed cells); The second stage: 170 °C × 10 min (for complete cross-linking and shaping). After curing, demold and then cure in an oven at 120 °C for 2 h to obtain foamed silicone rubber.

[0033] (3) The structure and function of the power conductor layer are as follows: Conductor: Annealed copper stranded wire with a cross-sectional area of 240 mm 2 (meeting the IEC 60228 standard), stranded in 3 layers with a pitch-diameter ratio of 12:1.

[0034] Insulation layer: Cross-linked polyethylene (XLPE), thickness 8 mm, withstand voltage level 220 kV.

[0035] Function: Transmit high-voltage electricity, and the insulation layer can withstand deep-sea high voltage and electrical stress.

[0036] (4) The materials, process and function of the non-metallic composite armor layer are as follows: Matrix material: Basalt fiber braided tape, single filament diameter 0.2 mm, tensile strength 2800 MPa, braided at a 45° crossing angle (fiber volume fraction 60%).

[0037] Modified material: Modified epoxy resin (epoxy value 0.45, polyamide 650 curing agent, adding 3wt% nano-silica), after impregnating the fiber, preheated at 80°C for 10 min and cured at 130°C for 2 h to form a continuous phase structure with a thickness of 8 mm.

[0038] (5) The materials and functions of the outer sheath layer are as follows: Materials: High-density polyethylene (HDPE) blended with 3wt% silicon carbide nanoparticles (100 nm), with a thickness of 5 mm.

[0039] Functions: Prevent biological attachment (such as barnacles, shark bites), and reduce the frictional resistance of ocean currents.

[0040] Example 2

[0041] A high-strength submarine high-voltage optoelectronic composite cable, including an optical fiber unit, an electromagnetic shielding - compressive layer, a power conductor layer, a non-metallic composite armor layer, and an outer sheath layer arranged in sequence from inside to outside: (1) The structure and functions of the optical fiber unit are as follows: Spiral skeleton: Made of polyether ether ketone (PEEK) material, with a spiral angle of 30°, a pitch of 50 mm, an outer diameter of 6 mm, and 24 grooves (single groove diameter 0.25 mm) inside.

[0042] Optical fiber arrangement: G.652.D single-mode optical fibers are embedded in the above grooves in a pre-stretched state of 0.1% to eliminate installation stress.

[0043] Filling material: Silicone gel (Shore A hardness 30, viscosity 5000 cP), filling the gap to buffer the external pressure, and forming a flexible support layer after curing.

[0044] Function: Inhibit the microbending loss caused by deep-sea high pressure.

[0045] (2) The structure, process, and functions of the electromagnetic shielding - compressive layer are as follows: Outer layer (shielding layer): Conductive graphene polyethylene, with a thickness of 2 mm.

[0046] Inner layer (compressive layer): Foamed silicone rubber, with a thickness of 4 mm and a density of 0.6 g / cm 3 .

[0047] Process: Double-layer co-extrusion molding (temperature 185°C) to ensure tight layer bonding.

[0048] Function: Block the electromagnetic interference of the power conductor, absorb the deformation of deep-sea pressure, and protect the optical fiber unit.

[0049] Among them, the conductive graphene polyethylene is prepared by the following steps: Raw materials: 100 parts (by mass) of high-density polyethylene (HDPE, melt index 0.5 g / 10 min), 7 parts (by mass) of graphene, and 1 part (by mass) of silane coupling agent KH-550.

[0050] Preparation steps: Weigh each raw material according to the parts by mass. Mix graphene and KH-550 in proportion, add absolute ethanol (solid-liquid ratio 1:20), and ultrasonically disperse for 30 min (power 300 W). Dry at 60 °C to remove the solvent to obtain pretreated graphene. Then add the pretreated graphene and high-density polyethylene to a twin-screw extruder (length-diameter ratio 40:1). Set the temperature zones: Zone 1: 155 °C (to prevent premature melting of PE); Zone 2: 175 °C (for melting and mixing); Zone 3: 190 °C (for uniform dispersion); screw speed 200 rpm, residence time 3 min, and extrude and pelletize. After completion, obtain pellets. Inject the pellets into a mold, press at 180 °C to form a 2-mm-thick sheet, cool and cut to obtain conductive graphene polyethylene.

[0051] Among them, the foamed silicone rubber is prepared by the following steps: Raw materials: 100 parts (by mass) of methyl vinyl silicone rubber (VMQ, hardness Shore A 30), 5 parts (by mass) of azodicarbonamide (decomposition temperature 160 °C), and 2 parts (by mass) of bis(2,5-dimethyl-2,5-di(tert-butylperoxy)hexane).

[0052] Preparation steps: Weigh each raw material according to the parts by mass. Plasticate the methyl vinyl silicone rubber on an open mill for 5 min (roll temperature 50 °C), add azodicarbonamide and bis(2,5-dimethyl-2,5-di(tert-butylperoxy)hexane), and knead for 10 min until uniform to obtain a rubber compound. Put the rubber compound into a mold and vulcanize in two stages on a flat vulcanizer: The first stage: 160 °C × 5 min (the blowing agent decomposes to generate gas to form closed cells); The second stage: 170 °C × 10 min (for complete cross-linking and shaping). After vulcanization, demold and then cure in an oven at 120 °C for 2 h to obtain foamed silicone rubber.

[0053] (3) The structure and function of the power conductor layer are as follows: Conductor: Annealed copper stranded wire with a cross-sectional area of 240 mm 2 (meeting the IEC 60228 standard), stranded in 3 layers with a pitch-diameter ratio of 12:1.

[0054] Insulation layer: Cross-linked polyethylene (XLPE), thickness 8 mm, withstand voltage level 220 kV.

[0055] Function: Transmit high-voltage electricity, and the insulation layer can withstand the high pressure and electrical stress in the deep sea.

[0056] (4) The materials, processes, and functions of the non-metallic composite armor layer are as follows: Matrix material: Basalt fiber braided tape, single fiber diameter 0.2 mm, tensile strength 2800 MPa, braided at a 45° crossing angle (fiber volume fraction 60%).

[0057] Modifying material: Modified epoxy resin (epoxy value 0.45, polyamide 650 curing agent, adding 3 wt% nano-silica), after impregnating the fibers, preheated at 80°C for 10 min and cured at 130°C for 2 h to form a continuous phase structure with a thickness of 8 mm.

[0058] (5) The material and function of the outer sheath layer are as follows: Material: High-density polyethylene (HDPE) blended with 3 wt% silicon carbide nanoparticles (20 nm), thickness 5 mm.

[0059] Function: Prevent biofouling (such as barnacles, shark bites), reduce the frictional resistance of ocean currents.

[0060] Example 3

[0061] A high-strength submarine high-voltage optoelectronic composite cable, including an optical fiber unit, an electromagnetic shielding - compressive layer, a power conductor layer, a non-metallic composite armor layer, and an outer sheath layer arranged in sequence from inside to outside: (1) The structure and function of the optical fiber unit are as follows: Spiral skeleton: Made of polyether ether ketone (PEEK) material, spiral angle 30°, pitch 50 mm, outer diameter 6 mm, with 24 grooves inside (single groove diameter 0.25 mm).

[0062] Optical fiber arrangement: G.652.D single-mode optical fibers are embedded in the above grooves in a pre-stretched state of 0.15% to eliminate installation stress.

[0063] Filling material: Silicone gel (Shore A hardness 30, viscosity 5000 cP), filling the gap to buffer the external pressure, and forming a flexible support layer after curing.

[0064] Function: Inhibit the microbending loss caused by deep-sea high pressure.

[0065] (2) The structure, process and function of the electromagnetic shielding - compressive layer are as follows: Outer layer (shielding layer): Conductive graphene polyethylene, thickness 2 mm.

[0066] Inner layer (compressive layer): Foamed silicone rubber, thickness 4 mm, density 0.7 g / cm 3 .

[0067] Process: Double-layer co-extrusion molding (temperature 185°C) to ensure tight layer bonding.

[0068] Function: Block the electromagnetic interference of the power conductor, absorb the deformation of deep-sea pressure, and protect the optical fiber unit.

[0069] Among them, the conductive graphene polyethylene is prepared by the following steps: Raw materials: 100 parts (by mass) of high-density polyethylene (HDPE, melt index 0.5 g / 10 min), 7 parts (by mass) of graphene, and 1 part (by mass) of silane coupling agent KH-550.

[0070] Preparation steps: Weigh each raw material according to the parts by mass. Mix graphene and KH-550 in proportion, add absolute ethanol (solid-liquid ratio 1:20), ultrasonically disperse for 30 min (power 300 W), dry at 60 °C to remove the solvent to obtain pretreated graphene. Then add the pretreated graphene and high-density polyethylene to a twin-screw extruder (length-diameter ratio 40:1), set the temperature zones: Zone 1: 160 °C (to prevent premature melting of PE); Zone 2: 180 °C (for melting and mixing); Zone 3: 190 °C (for uniform dispersion); screw speed 200 rpm, residence time 3 min, extrude and pelletize. After that, inject the pellets into a mold, press at 185 °C to form a 2-mm-thick sheet, cut after cooling to obtain the conductive graphene polyethylene.

[0071] Among them, the foamed silicone rubber is prepared by the following steps: Raw materials: 100 parts (by mass) of methyl vinyl silicone rubber (VMQ, hardness Shore A 30), 5 parts (by mass) of azodicarbonamide (decomposition temperature 160 °C), and 2 parts (by mass) of bis(2,5-dimethyl-2,5-di(tert-butylperoxy)hexane).

[0072] Preparation steps: Weigh each raw material according to the parts by mass. Plasticate the methyl vinyl silicone rubber on an open mill for 5 min (roll temperature 50 °C), add azodicarbonamide and bis(2,5-dimethyl-2,5-di(tert-butylperoxy)hexane), and knead for 10 min until uniform to obtain a rubber compound. Put the rubber compound into a mold and vulcanize in two stages on a flat vulcanizer: The first stage: 160 °C × 5 min (the blowing agent decomposes to generate gas to form closed cells); The second stage: 170 °C × 10 min (for complete cross-linking and shaping). After vulcanization, demold and then cure in an oven at 120 °C for 2 h to obtain the foamed silicone rubber.

[0073] (3) The structure and function of the power conductor layer are as follows: Conductor: Annealed copper stranded wire with a cross-sectional area of 240 mm 2 (meeting the IEC 60228 standard), stranded in 3 layers with a pitch-diameter ratio of 12:1.

[0074] Insulation layer: Cross-linked polyethylene (XLPE), thickness 8 mm, withstand voltage level 220 kV.

[0075] Function: Transmit high-voltage electricity, and the insulation layer can withstand the high pressure and electrical stress in the deep sea.

[0076] (4) The materials, processes, and functions of the non-metallic composite armor layer are as follows: Matrix material: Basalt fiber braided tape, single filament diameter 0.2 mm, tensile strength 2800 MPa, braided at a 45° crossing angle (fiber volume fraction 60%).

[0077] Modified material: Modified epoxy resin (epoxy value 0.45, polyamide 650 curing agent, adding 3 wt% nano-silica), after impregnating the fiber, preheated at 80 °C for 10 min and cured at 130 °C for 2 h to form a continuous phase structure with a thickness of 8 mm.

[0078] (5) The materials and functions of the outer sheath layer are as follows: Material: High-density polyethylene (HDPE) blended with 3 wt% silicon carbide nanoparticles (20 nm), thickness 5 mm.

[0079] Function: Prevent biological attachment (such as barnacles, shark bites), reduce the frictional resistance of ocean currents.

[0080] Settings of Comparative Examples 1 - 3 (control variable method): Specifically, Comparative Examples 1 - 3 are all control groups of Example 2, and the specific settings are as shown in Table 1 below: Table 1

[0081] Among them, the solid silicone rubber in Comparative Example 3 is the raw material methyl vinyl silicone rubber (VMQ, hardness Shore A 30) in Example 2.

[0082] Performance testing and data analysis: (1) Tensile strength test (GB / T 2952 - 2008) Method: Take a 1 m cable section, clamp both ends, stretch it at a rate of 10 mm / min until it breaks, record the maximum load, and the results are shown in Table 2 below: Table 2

[0083] (2) Optical signal loss test (IEC 60793 - 1 - 40) Method: Place the cable section in a 30 MPa pressure chamber, test the loss change at a wavelength of 1550 nm, and the results are shown in Table 3 below: Table 3

[0084] (3) Electromagnetic shielding effectiveness test (ASTM D4935 - 18) Method: Use the flange coaxial method to test the shielding effectiveness in the 1 MHz - 1 GHz frequency band, and the results are shown in Table 4 below: Table 4

[0085] (4)Fatigue life test (simulating ocean current impact) Method: Apply cyclic bending stress (strain 0.3%, frequency 2 Hz) to the cable section, record the number of fracture cycles, and the results are shown in Table 5 below: Table 5

[0086] It should be noted that in this document, terms such as "including", "comprising" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or elements inherent to such process, method, article or device.

[0087] Although the embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A high-strength submarine high-voltage optical and electrical composite cable, characterized in that, It includes an optical fiber unit, an electromagnetic shielding - compressive layer, a power conductor layer, a non - metallic composite armor layer, and an outer sheath layer which are arranged from the inside to the outside in sequence; The optical fiber unit is formed by pre - stretching an optical fiber and then embedding it into a polyether ether ketone helical skeleton, and filling and fixing it with silicone gel; The electromagnetic shielding - compressive layer includes an outer layer of conductive graphene polyethylene and an inner layer of foamed silicone rubber; The power conductor layer is composed of cross - linked polyethylene - coated annealed copper stranded wire; The non - metallic composite armor layer is made of basalt fiber braided tape impregnated with modified epoxy resin; The outer sheath layer is made of high - density polyethylene blended with 3wt% silicon carbide nanoparticles.

2. The high-strength submarine high-voltage optical and electrical composite cable according to claim 1, wherein The helical angle of the polyether ether ketone helical skeleton is 30°, the pitch is 50mm, the outer diameter is 6mm, and 24 grooves are arranged inside; the optical fiber is embedded in the grooves in a state of pre - stretching of 0.05% - 0.15%.

3. A high-strength submarine high-voltage optical power composite cable according to claim 1, characterized in that, The Shore A hardness of the silicone gel is 30 and the viscosity is 5000cP.

4. The high-strength submarine high-voltage optical and electrical composite cable according to claim 1, characterized in that, The thickness of the outer layer of conductive graphene polyethylene is 2mm; the inner layer of foamed silicone rubber The thickness is 4 mm, and the density of the foamed silicone rubber is 0.5 - 0.7 g / cm 3 .

5. A high-strength submarine high-voltage optical and electrical composite cable according to claim 1, characterized in that, The conductive graphene polyethylene is prepared by the following steps: First, the conductive graphene polyethylene includes the following raw materials in parts by mass: 100 parts of high - density polyethylene, 3 - 7 parts of graphene, and 1 part of silane coupling agent KH - 550; Then, weigh each raw material according to the parts by mass, mix graphene and KH - 550 in proportion, add absolute ethanol according to the solid - liquid ratio of 1:20, ultrasonically disperse for 30min, dry at 60℃ to remove the solvent to obtain pretreated graphene, then add the pretreated graphene and high - density polyethylene into a twin - screw extruder to extrude and granulate. After completion, obtain pellets, inject the pellets into a mold, press at 170 - 185℃ to form a 2mm - thick sheet, cut after cooling to obtain conductive graphene polyethylene.

6. The high-strength submarine high-voltage optical power composite cable according to claim 1, characterized in that The foamed silicone rubber is prepared by the following steps: First, the foamed silicone rubber includes the following raw materials in parts by mass: 100 parts of methyl vinyl silicone rubber, 4 - 5 parts of azodicarbonamide, and 1 - 2 parts of bis - 2,5 - dimethyl - 2,5 - di(t - butylperoxy)hexane; Then, weigh each raw material according to the parts by mass, plasticize the methyl vinyl silicone rubber on an open mill for 5min, add azodicarbonamide and bis - 2,5 - dimethyl - 2,5 - di(t - butylperoxy)hexane, mix and knead for 10min until uniform to obtain a rubber compound. Put the rubber compound into a mold and vulcanize in a flat vulcanizer in two stages: The first stage: 160℃×5min; The second stage: 170℃×10min. After vulcanization, demold and then place it in an oven at 120℃ for 2h of curing to obtain foamed silicone rubber.

7. A high-strength submarine high-voltage optical power composite cable according to claim 1, characterized in that, The single - filament diameter of the basalt fiber braided tape is 0.2mm and the tensile strength is 2800MPa.

8. The high-strength submarine high-voltage optical and electrical composite cable according to claim 1, wherein The modified epoxy resin contains 3wt% nano - silica.

9. A high-strength submarine high-voltage optical and electrical composite cable according to claim 1, characterized in that, The thickness of the outer sheath layer is 5mm.

Images