A wear-resistant and corrosion-resistant submarine optical cable and a preparation method thereof

Abstract

The present application relates to the technical field of submarine cable preparation, and particularly relates to a wear-resistant and corrosion-resistant submarine cable and a preparation method thereof. The wear-resistant and corrosion-resistant submarine cable comprises, from inside to outside, a center optical unit, a first armor layer, a copper pipe layer, an insulation layer, a second armor layer, a first resin filling layer, a wear-resistant organic material layer, a rubber filling layer, a third armor layer, a second resin filling layer and a composite sheath layer. The third armor layer is obtained by spacing twisting the galvanized steel wire or zinc alloy plated steel wire outside the rubber filling layer. The present application embeds the steel wire in a spacing twisting mode, breaks through the layer number limitation of the traditional one or two layers of outer armor of the submarine cable, introduces a resin-based viscous rubber filler to fill the gap between the steel wires, forms an integrated structure, significantly improves the overall breaking tensile force of the optical cable, and can resist the long-term corrosion of seawater, the severe wear of rocks and trawl nets, and the continuous erosion of salt spray environment, so that the optical cable can keep long-term reliable operation.

Description

Technical Field

[0001] This invention relates to the field of submarine optical cable manufacturing technology, specifically to a wear-resistant and corrosion-resistant submarine optical cable and its manufacturing method. Background Technology

[0002] Currently, the submarine optical cables commonly used in the marine communication field are mainly of two types: SA (single-armored) and DA (double-armored). These cables typically consist of a central optical unit, inner steel wires, a copper conductor tube, an insulation layer, outer steel wires, and an outer sheath. The core difference between the two lies in the number of outer armor steel wires: SA-type cables are mainly used in medium-risk areas with greater water depth (hundreds to thousands of meters) and relatively flat seabeds, but still with slight rock friction, such as scenarios involving sporadic fishing trawling, small anchor scraping, or slight ocean current scouring; while DA-type cables mainly serve shallow water areas to resist direct mechanical damage caused by anchors, etc. However, when faced with special and harsh environments, such as complex and variable nearshore sea conditions, rugged rocky bottoms, or even extreme laying paths extending directly from steep cliffs into the sea, the structural shortcomings of traditional SA / DA submarine cables make it difficult for their performance to meet environmental requirements. These types of submarine cables are relatively lightweight, and under the repeated erosion of tides and waves, they easily sway and rub against rough rock surfaces. Day after day, this mechanical wear gradually erodes the outer sheath, outer steel wires, and even the insulation layer, ultimately threatening the safety of the optical communication unit. Even more serious is the fact that during this wear process, the high concentration of salt spray permeating the seashore is relentlessly penetrating—accelerating its penetration along the damaged areas, causing the exposed metal armor and structural layers to fall into a vicious cycle of electrochemical corrosion. Wear and corrosion reinforce each other, continuously escalating the problem and rapidly rendering the traditional protective system of optical cables ineffective.

[0003] Existing technology, utility model patent CN210142533U discloses a submarine optical cable, including an optical unit, an armor layer stranded outside the optical unit, a conductor layer covering the armor layer, an insulation layer extruded on the conductor layer, a reinforcing layer covering the insulation layer, and an outer sheath extruded outside the reinforcing layer. The submarine optical cable also includes a sensing optical fiber, which is distributed between the reinforcing layer and the outer sheath. Utility model patent CN212301996U discloses a lightweight protective submarine optical cable, including an optical fiber unit, an inner armor layer, a conductor, an insulation layer, an outer armor layer, and an outer sheath. Multiple inner armor layers are spirally stranded outside the optical fiber unit. A conductor is provided outside the inner armor layer, and an insulation layer is extruded outside the conductor. An outer armor layer is longitudinally wrapped outside the insulation layer, and an outer sheath is extruded outside the outer armor layer. The optical fiber unit is composed of an optical fiber and a stainless steel tube.

[0004] Existing submarine optical cables are limited by manufacturing processes, typically producing only two to three layers of steel wire and one to two armor layers. Furthermore, to achieve the required minimum breaking load, only high-strength steel wire can be used. However, high-strength steel wire has a low carbon content during manufacturing, resulting in insufficient corrosion resistance. Therefore, traditional submarine optical cables struggle to simultaneously achieve both minimum breaking load and corrosion resistance. To meet the demands of the diverse and harsh underwater environment, there is an urgent need for a submarine optical cable that combines abrasion resistance, corrosion resistance, and tensile strength. Summary of the Invention

[0005] To address the technical challenges of submarine optical cables prepared using traditional methods as described in the background art being rapidly corroded, worn, and broken in harsh underwater environments, this invention provides a wear-resistant and corrosion-resistant submarine optical cable and its preparation method.

[0006] To achieve the above technical objectives, the following technical solution is provided: In a first aspect, the present invention provides a wear-resistant and corrosion-resistant submarine optical cable, comprising, from the inside out: A central optical unit, comprising an optical fiber, a water-blocking filler, and a stainless steel tube; The first armor layer is formed by twisting phosphated steel wire around the outside of the central optical unit; A copper tube layer covers the outside of the first armor layer; The insulating layer is formed by covering the outside of the copper tube layer with polyethylene; the polyethylene is high-density polyethylene. The second armor layer is formed by twisting galvanized steel wire or zinc alloy coated steel wire around the outside of the insulation layer; further, the second armor layer includes two layers of the galvanized steel wire or zinc alloy coated steel wire, and the surface of the galvanized steel wire or zinc alloy coated steel wire is coated with an asphalt layer.

[0007] The first resin filling layer is obtained by filling the gaps between adjacent galvanized steel wires or zinc alloy coated steel wires of the second armor layer with a resin-based adhesive. Further, after the resin-based adhesive is cured, it forms an integral bonding structure with the galvanized steel wires or zinc alloy coated steel wires. The resin-based adhesive is selected from at least one of epoxy resin, polyurethane adhesive, and resin-based hot melt adhesive. The resin matrix of the resin-based hot melt adhesive is a thermoplastic resin, including at least one of ethylene-vinyl acetate copolymer (EVA) and polyamide.

[0008] The wear-resistant organic material layer is obtained by coating the outside of the first resin-filled layer with a wear-resistant organic material; further, the wear-resistant organic material is selected from at least one of high-density polyethylene and thermoplastic polyurethane.

[0009] The adhesive filler layer is obtained by applying a resin-based viscous colloid to the exterior of the wear-resistant organic material layer; further, the resin-based viscous colloid is selected from at least one of epoxy resin adhesive, polyurethane adhesive, and resin-based hot melt adhesive, wherein the resin matrix of the resin-based hot melt adhesive is a thermoplastic resin, including at least one of ethylene-vinyl acetate copolymer (EVA) and polyamide; further, the resin-based viscous colloid used in the adhesive filler layer has a curing time of <3 seconds, wherein curing refers to the surface drying and solidification of the resin-based viscous colloid, with no flowability.

[0010] The third armor layer is formed by intermittently twisting galvanized steel wire or zinc alloy coated steel wire outside the adhesive filler layer; further, the meaning of intermittent twisting is: during the twisting process, two adjacent galvanized steel wires or zinc alloy coated steel wires are not tightly attached, but maintain a preset interval distance, which is 0.8-1.5 times the outer diameter of the steel wire; Furthermore, the outer diameter of the galvanized steel wire or zinc alloy coated steel wire used in the third armor layer is 1.0-4.0 mm; the outer diameter of the galvanized steel wire or zinc alloy coated steel wire used in the first armor layer is 0.5-2 mm; and the outer diameter of the galvanized steel wire or zinc alloy coated steel wire used in the second armor layer is 1.2-4.2 mm.

[0011] Furthermore, the technical significance of the intermittent twisting lies in providing a uniform space for the subsequent application of the second resin filling layer, allowing the viscous colloid to fully penetrate and fill the gaps between the steel wires, and after curing, forming a strong composite structure between the steel wires and the resin. This structure can not only effectively disperse external pressure and prevent deformation or breakage due to local stress concentration in the steel wires, but also further isolate seawater through the resin layer, thereby improving the overall tensile strength and corrosion resistance of the armor layer.

[0012] The second resin filling layer is formed by filling the gaps between adjacent galvanized steel wires or zinc alloy coated steel wires of the third armor layer with a resin-based adhesive and covering the surface of the third armor layer; further, the resin-based adhesive is selected from at least one of epoxy resin, polyurethane adhesive, and resin-based hot melt adhesive, and the resin matrix of the resin-based hot melt adhesive is a thermoplastic resin, including at least one of ethylene-vinyl acetate copolymer (EVA) and polyamide. A composite sheath layer is obtained by extruding it onto the outside of the second resin filler layer. The composite sheath layer is made of polyethylene or a mixture of polyethylene and polyurethane. Further, in the polyethylene and polyurethane mixture, the polyethylene content is ≥63% by mass percentage. In a second aspect, the present invention provides a method for preparing a wear-resistant and corrosion-resistant submarine optical cable as described in the first aspect, comprising the following steps: S1. Optical unit fabrication: Water-blocking filler is injected into a stainless steel tube and an optical fiber is inserted. The central optical unit is fabricated by drawing, diameter reduction and continuous welding processes. S2. Preparation of the first armor layer and copper tube layer: Phosphated steel wire is twisted and wrapped around the outside of the central optical unit. Copper strip is wound around the outside of the cable core with the twisted armor layer and welded together. They are then fed into a copper tube rolling mold for drawing and welding to form a cable core with the copper tube layer. S3. Insulation layer preparation: High-density polyethylene is continuously extruded and wrapped around the cable core with copper tube layer using a high-temperature extrusion process to obtain the insulation layer. S4. Preparation of the second armor layer: Galvanized steel wire or zinc alloy coated steel wire is stranded outside the insulation layer to form the second armor layer; S5. Preparation of the first resin filling layer: The gaps between the stranded steel wires of the second armor layer are filled with resin-based adhesive colloid, which is cured to form the first resin filling layer. S6. Preparation of wear-resistant organic material layer: A wear-resistant organic material is coated on the outer layer of the first resin filling layer to form the wear-resistant organic material layer; S7. Preparation of adhesive filler layer: A resin-based adhesive is coated on the outer surface of the wear-resistant organic material layer to form the adhesive filler layer; S8. Preparation of the third armor layer: Galvanized steel wire or zinc alloy coated steel wire is intermittently twisted onto the surface of the adhesive filler layer to form the third armor layer; S9. Preparation of the second resin filling layer: Fill the gaps between the stranded steel wires of the third armor layer with resin-based adhesive and cure it, and cover the surface of the third armor layer with resin-based adhesive to form the second resin filling layer. S10, Preparation of composite sheath layer: On the outer surface of the second resin filler layer, a composite material made of polyethylene or a mixture of polyethylene and polyurethane is extruded to form the composite sheath layer; the polyethylene is high-density polyethylene.

[0013] Furthermore, in the S8 intermediate stranding process, the two adjacent galvanized steel wires or zinc alloy coated steel wires are not tightly bonded together, but maintain a preset interval distance, which is 0.8-1.5 times the outer diameter of the steel wire. Furthermore, the outer diameter of the galvanized steel wire or zinc alloy coated steel wire is 1.0 mm to 4.0 mm.

[0014] Furthermore, the galvanized steel wire or zinc alloy coated steel wire mentioned in S8 is pre-formed by a pre-forming device, with the wire tension of the galvanized steel wire or zinc alloy coated steel wire set to 100 N-300 N and the stranding pitch to 300 mm-500 mm, and then single-layer stranded by an armoring device. Furthermore, the resin-based adhesive in S5, S7, and S9 is selected from at least one of epoxy resin adhesive, polyurethane adhesive, and resin-based hot melt adhesive, and the resin matrix of the resin-based hot melt adhesive is a thermoplastic resin, including at least one of ethylene-vinyl acetate copolymer (EVA) and polyamide. Furthermore, in S4, the second armor layer has two layers of stranded steel wires; Furthermore, in S4, asphalt is coated on the surface of the steel wire, which not only gives the optical cable foundation tensile strength, but also improves the corrosion resistance of the steel wire through the sealing effect of the asphalt, effectively delaying the erosion of seawater and salt spray. Furthermore, the resin-based adhesive described in S5 forms an integral bonding structure with the steel wire after curing, which significantly enhances the integrity and anti-loosening ability of the armor layer. Furthermore, the wear-resistant organic material described in S6 has high hardness and low coefficient of friction, which can effectively resist long-term wear on the outer layer of the optical cable from objects such as seabed rocks and trawl nets.

[0015] Furthermore, the adhesive filler described in S7 is used to ensure the adhesion between the interleaved galvanized steel wires or zinc alloy coated steel wires, which not only plays a role in buffering and sealing, but also enhances the interfacial bonding force between the third armor layer and the wear-resistant organic material layer.

[0016] Furthermore, S9, the second resin filling layer is used to seal the gaps between the steel wires, on the one hand preventing salt spray from penetrating inward along the gaps, and on the other hand enhancing the adhesion of the composite sheath layer.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This invention uses an intermittent stranding method to embed galvanized steel wire or zinc alloy coated steel wire, breaking through the traditional limitation of one or two layers in submarine cable armor. It reasonably increases the number of armor layers within a limited space, and introduces resin-based adhesive filler to fill the gaps in the steel wires to form an integrated structure. This effectively improves the adhesion between the layers, ensuring that the armor layers maintain a high degree of integration when subjected to complex mechanical stress, avoiding local failure caused by relative slippage, and significantly improving the overall tensile strength of the optical cable at break.

[0018] 2. This invention provides a multi-layered composite protection system to ensure wear and corrosion resistance. By synergistically utilizing adhesive fillers, resin fillers, wear-resistant organic materials, and a composite sheath material made of polyethylene and polyurethane, a multi-layered protective barrier is constructed from the inside out. This system can simultaneously resist long-term corrosion from seawater, severe abrasion from rocks and trawl nets, and continuous erosion from salt spray environments, enabling optical cables to maintain long-term reliable operation even in extreme conditions such as cliff-entry and shallow rocky areas. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 A cross-sectional view of the wear-resistant and corrosion-resistant submarine optical cable provided by the present invention; Among them, 1-central optical unit, 2-first armor layer, 3-copper tube layer, 4-insulation layer, 5-second armor layer, 6-first resin filling layer, 7-wear-resistant organic material layer, 8-adhesive filling layer, 9-second resin filling layer, 10-third armor layer, and 11-composite sheath layer. Detailed Implementation

[0021] The present invention will be further described below with reference to embodiments, but the scope of protection of the present invention is not limited thereto. It should be noted that the implementation steps in the embodiments can be further adjusted according to the specific experimental environment, and the implementation steps not specified are usually conditions in conventional experiments.

[0022] Example 1 This embodiment provides a wear-resistant and corrosion-resistant submarine optical cable and its preparation method, including the following steps: Step 1: Optical Unit Fabrication Excess fiber paste (water-blocking filler) is precisely injected into the stainless steel tube to ensure that the optical fiber receives sufficient buffering and sealing protection inside the tube; then, through drawing and diameter reduction and continuous welding processes, a dense and stable central optical unit is produced.

[0023] Step 2: Preparation of the first armor layer and copper tube layer Phosphated steel wire is stranded and wrapped around the outside of the central optical unit to form a first armor layer; copper strip is wound around the cable core with the first armor layer and welded together, and then fed into a copper tube winding mold for drawing and welding to form a cable core with a copper tube layer. In this embodiment, the outer diameter of the phosphated steel wire is 2.15 mm and the stranding pitch is 200 mm.

[0024] Step 3: Preparation of Insulating Layer A high-density polyethylene (HDPE) insulation layer is obtained by continuously extruding high-density polyethylene over a cable core with a copper tube layer using a high-temperature extrusion process. In this embodiment, the insulation layer has a thickness of 3.0 mm.

[0025] Step 4: Preparation of the second armor layer Two layers of galvanized steel wire are stranded outside the insulation layer to form a second armor layer, and a layer of asphalt with a thickness of 0.1 mm is uniformly coated on the surface of the galvanized steel wire. In this embodiment, the outer diameter of the galvanized steel wire is 3.23 mm. This step not only imparts tensile strength to the optical cable foundation, but also improves the corrosion resistance of the steel wire through the sealing effect of the asphalt.

[0026] Step 5: Preparation of the first resin filler layer Epoxy resin (a resin-based adhesive) is filled into the gaps between the stranded steel wires of the second armor layer. After curing, this filler forms an integral bond with the steel wires, significantly enhancing the integrity and anti-loosening ability of the armor layer, thus forming the first resin-filled layer.

[0027] Step 6: Preparation of the wear-resistant organic material layer Outside the first resin-filled layer, a layer of high-density polyethylene (HDPE) is extruded to form a wear-resistant organic material layer. In this embodiment, the thickness of the wear-resistant organic material layer is 2.5 mm. This material has high hardness and a low coefficient of friction, effectively resisting long-term wear from seabed rocks and trawl nets on the outer layer of the optical cable.

[0028] Step 7: Preparation of the adhesive filler layer A layer of polyurethane adhesive (resin-based viscous colloid) is uniformly applied to the outer surface of the wear-resistant organic material layer to form an adhesive filler layer. In this embodiment, the surface drying and curing time of the polyurethane adhesive is 2 seconds (<3 seconds). This adhesive layer not only serves as a buffer and sealant but also enhances the interfacial bonding between the subsequent third armor layer and the inner structure.

[0029] Step 8: Preparation of the Third Armor Layer The galvanized steel wires are intermittently twisted onto the surface of the adhesive filler layer using a preforming device to form a third armor layer. In this embodiment, the outer diameter of the galvanized steel wire is 3.55 mm, and a preset interval distance of 3.55 mm (i.e., 1.0 times the outer diameter of the steel wire) is maintained between two adjacent steel wires; the wire tension is set to 200 N, and the twisting pitch is 400 mm.

[0030] Step 9: Preparation of the second resin filling layer Polyurethane adhesive is filled into the gaps between the stranded steel wires of the third armor layer and cured. Simultaneously, polyurethane adhesive is applied to the surface of the third armor layer to form a second resin-filled layer. This further seals the gaps between the steel wires, preventing salt spray from penetrating inwards along the seams.

[0031] Step 10: Preparation of the composite sheath layer Finally, a composite material made of polyethylene and polyurethane is extruded onto the outer surface of the second resin filler layer using an extrusion process to form a composite sheath layer. In this embodiment, the mass percentage of polyethylene in the mixture is 70%, and the thickness of the composite sheath layer is 3.0 mm. This composite sheath combines the weather resistance of polyethylene with the high wear resistance and high elasticity of polyurethane.

[0032] Example 2 This embodiment shares the same basic structure and preparation steps as Embodiment 1. The main difference lies in the selection of some materials and the values ​​of process parameters, which tend to be closer to the lower limit of the scope of the claims or specific combinations thereof. The specific differences are as follows: In the first armor layer, the outer diameter of the phosphated steel wire is 1.5 mm; the thickness of the insulation layer is 1.5 mm.

[0033] In the second armor layer, two layers of zinc alloy coated steel wire are used instead of galvanized steel wire. The outer diameter of the steel wire is 2.0 mm, and the thickness of the surface asphalt layer is 0.05 mm.

[0034] In the first and second resin filler layers, the resin-based adhesive is replaced with a resin-based hot melt adhesive, and the resin matrix is ​​ethylene-vinyl acetate copolymer (EVA).

[0035] In the wear-resistant organic material layer, thermoplastic polyurethane (TPU) is used instead of high-density polyethylene, with a thickness of 1.0 mm.

[0036] In the adhesive filler layer, a resin-based hot melt adhesive is used, and the resin matrix is ​​polyamide.

[0037] In the third armor layer, zinc alloy coated steel wire is used, with an outer diameter of 2.90 mm; the preset interval between two adjacent steel wires is 2.32 mm (i.e., 0.8 times the outer diameter of the steel wire); the wire tension is set to 100 N, and the twisting pitch is set to 300 mm.

[0038] In the composite sheath layer, the polyethylene content in the polyethylene and polyurethane mixture is 63% by mass, and the thickness of the composite sheath layer is 2.0 mm.

[0039] Example 3 This embodiment shares the same basic structure and preparation steps as Embodiment 1. The main difference lies in the selection of some materials and the values ​​of process parameters, which tend to be closer to the upper limit of the scope of the claims or another specific combination. The specific differences are as follows: In the first armor layer, the outer diameter of the phosphated steel wire is 3.0 mm; the thickness of the insulation layer is 3.0 mm.

[0040] The second armor layer uses two layers of galvanized steel wire with an outer diameter of 4.0 mm and a surface asphalt layer thickness of 0.2 mm.

[0041] In the first and second resin filler layers, the resin-based adhesive is replaced with polyurethane adhesive.

[0042] The wear-resistant organic material layer uses high-density polyethylene (HDPE) with a thickness of 2.5 mm.

[0043] In the adhesive filler layer, epoxy resin adhesive is used, and its surface drying curing time is 2.5 seconds.

[0044] In the third armor layer, galvanized steel wire with an outer diameter of 4.0 mm is used; the preset interval between two adjacent steel wires is 6.0 mm (i.e., 1.5 times the outer diameter of the steel wire); the wire tension is set to 300 N and the twisting pitch is set to 500 mm.

[0045] In the composite sheath layer, the polyethylene content in the polyethylene and polyurethane mixture is 80% by mass, and the thickness of the composite sheath layer is 4.0 mm.

[0046] Comparative Example 1 The third armor layer consists of uninterrupted stranded galvanized steel wire, and the remaining preparation conditions are the same as in Example 1.

[0047] Comparative Example 2 The third armor layer consists of interleaved strands of galvanized steel wire, and no second resin-filled layer is prepared. All other preparation conditions are the same as in Example 1.

[0048] Comparative Example 3 The third armor layer consists of stranded galvanized steel wire without gaps. The first and second resin filling layers are not prepared. All other preparation conditions are the same as in Example 1.

[0049] Comparative Example 4 Instead of preparing the third armor layer and the second resin filler layer, the composite sheath layer is directly coated over the adhesive filler layer, and all other preparation conditions are the same as in Example 1.

[0050] Comparative Example 5 The third armor layer, the second resin filling layer, the adhesive filling layer, and the composite sheath layer are not prepared. Instead, two layers of wrapped PP rope are covered on the surface of the wear-resistant organic material layer outside the second armor layer. All other preparation conditions are the same as in Example 1.

[0051] Experimental Example The performance of the submarine optical cables prepared in the examples and comparative examples was tested: (1) According to Appendix F of the communication industry product standard YD / T 2283-2020, the adhesion between the third armor layer and the adhesive filler layer in Examples 1-3 and Comparative Examples 1-3, as well as the adhesion between the second armor layer and the insulation layer and the insulation layer and the copper tube layer in Examples 1-3 and Comparative Examples 1-5, were tested. The test results are shown in the table below:

[0052] The data in the table shows that: The adhesion between the insulation layer and the copper tube layer in Examples 1-3 and Comparative Examples 1-5 is higher than the adhesion between the second armor layer and the insulation layer; the adhesion between the second armor layer and the insulation layer in Comparative Examples 1 and 3 is higher than the adhesion between the third armor layer and the adhesive filler layer; while in Examples 1-3 and Comparative Example 2, which uses intermittent twisting, the adhesion between the third armor layer and the adhesive filler layer is higher than the adhesion between the second armor layer and the insulation layer.

[0053] (2) According to Appendix E of the communication industry product standard YD / T 2283-2020, the ultimate tensile strength (UTS) of the Example 1 and Comparative Example 4 was tested; the UTS of the submarine optical cable prepared in Example 1 was ≥700KN, and the UTS of the conventional outer armored submarine optical cable prepared in Comparative Example 4 was <500KN.

[0054] (3) According to the communication industry product standard GB / T 7424.21-2021 E2 abrasion-resistant special rock grinding test method, the abrasion performance of submarine optical cables was tested. Granite rock was used for grinding. The submarine optical cables prepared in Example 1 and Comparative Example 5 were continuously rubbed for 6 hours under a load of 100KN. The wear of the composite sheath layer in Example 1 did not exceed 40% of the nominal thickness of the sheath. The outer PP rope of Comparative Example 5 was broken after 5 wear cycles, and the second armor layer was worn by 0.1mm. According to the theoretical calculation based on the number of structural layers, Example 1 can meet more than 15,000 wear cycles, and Comparative Example 5 meets less than 9,000 wear cycles. Therefore, the structural abrasion resistance of Example 1 is 1.6 times that of Comparative Example 5.

[0055] (4) According to the communication industry product standards YD / T 2283-2020 GB / T 2423.17 (IEC 60068-2-11) Neutral Salt Spray (NSS) and IEC60794-1-220 F20 Salt Spray Corrosion Method for Optical Cables, the interlayers of the submarine optical cable prepared in Example 1 passed the salt spray test. The total number of protective layers of the submarine optical cable in Example 1 is more than that of the submarine optical cable in Comparative Example 5. This structural difference brings it better corrosion resistance.

[0056] (5) The interlayer bonding is sufficient to support the increase in the number of armor layers: The tensile strength at break of 500 kN was tested according to standard 7.6.5 of submarine optical cable YDT2283-2080. Examples 1-3 and Comparative Examples 1-5 were tested as follows: Experimental results: The submarine optical cables of Examples 1-3 and Comparative Examples 2, 4 and 5 all passed the test. Comparative Examples 1 and 3 showed cable slippage and failed the test.

[0057] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A wear-resistant and corrosion-resistant submarine optical cable, characterized in that, From the inside out, it includes: Central optical unit; The first armor layer is formed by twisting phosphated steel wire around the outside of the central optical unit; A copper tube layer covers the outside of the first armor layer; The insulating layer is formed by covering the outside of the copper tube layer with polyethylene. The second armor layer is formed by twisting galvanized steel wire or zinc alloy coated steel wire around the outside of the insulation layer; The first resin filling layer is obtained by filling the gaps between adjacent galvanized steel wires or zinc alloy coated steel wires of the second armor layer with a resin-based viscous colloid. The wear-resistant organic material layer is obtained by coating the outside of the first resin-filled layer with wear-resistant organic material; The adhesive filler layer is obtained by applying a resin-based viscous colloid to the outside of the wear-resistant organic material layer; The third armor layer is formed by intermittently twisting galvanized steel wire or zinc alloy coated steel wire outside the adhesive filler layer; the intermittent twisting is achieved by maintaining a preset interval between two adjacent galvanized steel wires or zinc alloy coated steel wires during the twisting process, and the preset interval is 0.8-1.5 times the outer diameter of the galvanized steel wire or zinc alloy coated steel wire. The second resin filling layer is obtained by filling the gaps between adjacent galvanized steel wires or zinc alloy coated steel wires of the third armor layer with a resin-based viscous colloid and covering the surface of the third armor layer. The composite sheath layer is obtained by extruding polyethylene or a mixture of polyethylene and polyurethane onto the outside of the second resin-filled layer.

2. The submarine optical cable according to claim 1, characterized in that, The second armor layer comprises two layers of galvanized steel wire or zinc alloy coated steel wire.

3. The submarine optical cable according to claim 1 or 2, characterized in that, The surface of the galvanized steel wire or zinc alloy coated steel wire of the second armor layer is coated with an asphalt layer.

4. The submarine optical cable according to claim 1 or 2, characterized in that, The resin-based adhesive is selected from at least one of epoxy resin adhesive, polyurethane adhesive, and resin-based hot melt adhesive. The resin matrix of the resin-based hot melt adhesive is a thermoplastic resin, including at least one of ethylene-vinyl acetate copolymer (EVA) and polyamide.

5. The submarine optical cable according to claim 1 or 2, characterized in that, The wear-resistant organic material is selected from at least one of high-density polyethylene and thermoplastic polyurethane.

6. The submarine optical cable according to claim 1 or 2, characterized in that, In the polyethylene and polyurethane mixture, the polyethylene content is ≥63% by mass percentage.

7. A method for manufacturing a submarine optical cable as described in any one of claims 1 to 6, characterized in that, Including the following steps: Water-blocking filler is injected into a stainless steel tube and an optical fiber is inserted. The central optical unit is then manufactured through a drawing and diameter reduction process and a continuous welding process. Phosphated steel wire is twisted and wrapped around the outside of the central optical unit to obtain the first armor layer; The copper strip is wrapped around the outside of the first armor layer and welded to form a copper tube, thus obtaining the copper tube layer. A high-density polyethylene layer is continuously extruded over the copper tube layer to obtain an insulation layer. A second armor layer is formed by stranding galvanized steel wire or zinc alloy coated steel wire around the insulation layer. A resin-based adhesive is filled into the gaps between the stranded steel wires of the second armor layer, and after curing, the first resin-filled layer is formed. A wear-resistant organic material is coated on the outer layer of the first resin filler layer to form the wear-resistant organic material layer; A resin-based adhesive is coated on the outer surface of the wear-resistant organic material layer to form the adhesive filler layer; Galvanized steel wire or zinc alloy coated steel wire is intermittently twisted onto the surface of the adhesive filler layer to form the third armor layer; A resin-based adhesive is filled into the gaps between the stranded steel wires of the third armor layer and cured, and then a resin-based adhesive is applied to the surface of the third armor layer to form the second resin filling layer. On the outer surface of the second resin filler layer, polyethylene or a composite material made of polyethylene and polyurethane is extruded to form the composite sheath layer.

8. The preparation method according to claim 7, characterized in that, The polyethylene or a composite material made of polyethylene and polyurethane, wherein the polyethylene is high-density polyethylene.

9. The preparation method according to claim 7 or 8, characterized in that, The outer diameter of the galvanized steel wire or zinc alloy coated steel wire is 1.0 mm to 4.0 mm.

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