A compression and torsion resistant submarine cable

Abstract

The application provides a kind of anti-pressure anti-torsion submarine cable, including center support, a plurality of conductor units, a plurality of edge gap supports, optical fiber units, signal transmission units and protective anti-torsion anti-pressure units.The conductor units are arranged around the periphery of the center support, and the edge gap supports are arranged between adjacent conductor units.The optical fiber units and the signal transmission units are respectively embedded in different edge gap supports.The protective anti-torsion anti-pressure units include, from outside to inside, a first protective layer, a first water-blocking layer, a first anti-tension anti-torsion armor layer, a second protective layer, a second anti-tension anti-torsion armor layer, a second water-blocking layer, and a third protective layer.The application realizes surface contact pressure resistance through the center support, realizes anti-torsion through the double armor layer of reverse cross-weaving, isolates electromagnetic interference and provides rigid protection through the independently embedded optical fiber and signal units, and solves the problem of insufficient anti-pressure, anti-torsion, optical and electrical interference, and water-blocking performance of the existing submarine cable by combining the multi-layer continuous water-blocking structure.

Description

Technical Field

[0001] This invention relates to the field of cable technology, and more specifically to a pressure- and torsion-resistant submarine cable. Background Technology

[0002] As marine resource development extends to the deep sea, submarine cables, as key carriers of energy and data transmission, face increasingly harsh service environments. High pressure in the deep sea, strong ocean currents, complex seabed topography, and dynamic loads during laying and retrieval place extremely high demands on the compressive strength, torsional strength, water-blocking sealing, and long-term structural stability of submarine cables.

[0003] Existing submarine cables, when addressing the aforementioned challenges, suffer from the following main technical deficiencies: In deep-sea environments, cables must withstand immense hydrostatic pressure as well as dynamic impacts from ocean currents and marine life. Traditional cable structures, with their relatively simple internal filling and buffer layers, are ill-suited for effectively dissipating external pressure. When pressure is directly transmitted to the cable core, it can cause insulation deformation, fiber optic signal attenuation, and in severe cases, even permanent damage to the cable's internal structure, affecting the stable transmission of power or signals.

[0004] Traditional submarine cables typically employ a circular cross-section central support member, which forms only line contact with the surrounding conductor units. This small contact area results in extremely uneven stress distribution. Under the long-term effects of ultra-high hydrostatic pressure and external impact loads in the deep sea, this line contact structure is highly susceptible to severe stress concentration, leading to radial displacement or circumferential slippage of the conductor units. This, in turn, compresses the insulation layer inside the conductor units, causing uneven insulation thickness, localized damage, or even insulation breakdown, significantly shortening the cable's service life.

[0005] Furthermore, in existing fiber optic composite submarine cables, optical fiber units are typically directly twisted together with power conductor units and filled into the gaps between the conductor units. The strong electromagnetic fields generated during power transmission can cause severe electromagnetic interference to the optical signals transmitted through the optical fibers, leading to increased signal attenuation, shortened transmission distance, and a significantly higher bit error rate. Simultaneously, optical fiber units generally lack independent rigid protective structures. When the cable is subjected to external pressure or torsional loads, the optical fibers are easily squeezed, bent, or sheared, causing interruptions in optical signal transmission and drastically reducing the reliability of signal transmission.

[0006] Furthermore, the gap between the conductor units and the outer sheath of existing submarine cables is usually filled with ordinary filler strips or filler ropes. These fillers have limited mechanical properties and cannot form effective surface contact support with adjacent conductor units and sheath layers. Under the combined action of external pressure and torsional loads, relative displacement and deformation easily occur between the functional layers, damaging the overall structural integrity of the cable and failing to form a synergistic compressive and torsional resistance structure, further reducing the mechanical properties of the cable.

[0007] In summary, how to provide a new type of submarine cable that can simultaneously solve the problems of pressure resistance, torsion resistance, photoelectric interference, water blockage, and structural integrity is a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0008] This invention is made to solve the above-mentioned problems, and its purpose is to provide a pressure- and torsion-resistant submarine cable.

[0009] The present invention provides a pressure- and torsion-resistant submarine cable, characterized by comprising: a central support member, multiple conductor units, multiple edge support members, at least one optical fiber unit, at least one signal transmission unit, and a protective torsion and pressure-resistant unit; The central support is in the shape of a Reuleaux polygon and is located at the center of the cable. The number of sides of the central support is the same as the number of conductor units. Multiple conductor units are arranged around the outer periphery of the central support, and a side gap support is provided between each two adjacent conductor units; The fiber optic unit and the signal transmission unit are respectively embedded in different edge support components; The protective anti-torsion and anti-compression unit covers the outer periphery of the conductor unit, the edge support, the optical fiber unit and the signal transmission unit. The protective anti-torsion and anti-compression unit includes, from the outside to the inside, a first protective layer, a first water-blocking layer, a first tensile and torsion-resistant armor layer, a second protective layer, a second tensile and torsion-resistant armor layer, a second water-blocking layer and a third protective layer.

[0010] Furthermore, the first and second shielding layers are shielding layers woven from tin-plated copper wire or nickel-plated carbon fiber.

[0011] Furthermore, both the first tensile and torsional armor layer and the second tensile and torsional armor layer are made of high-strength materials through a cross-weaving process, and the weaving directions of the two are opposite.

[0012] Furthermore, the conductor unit, from the inside out, includes a conductive core, a conductor semiconducting shielding layer, a main insulation layer, an insulating semiconducting shielding layer, a first semiconducting water-resistant layer, a metal shielding layer, a second semiconducting water-resistant layer, and a semiconducting layer; wherein, the conductive core is composed of multiple first copper conductors, and water-blocking adhesive is filled between adjacent first copper conductors; the material of the main insulation layer is any one of cross-linked polyethylene, ethylene propylene rubber, or polyolefin insulating material; the materials of the conductor semiconducting shielding layer and the insulating semiconducting shielding layer are both carbon black-filled semiconducting composite materials.

[0013] Furthermore, the metal shielding layer can be any one of a copper strip structure, a steel strip structure, or a copper wire braided structure; the first semiconducting resistive water layer and the second semiconducting resistive water layer can be any one of a semiconducting resistive water strip or a semiconducting resistive water paste.

[0014] Furthermore, the material of the central support is any one of rigid engineering plastic, fiberglass, or aluminum alloy; the material of the edge support is any one of elastic rubber, polyurethane, or glass fiber composite material.

[0015] Furthermore, the optical fiber unit comprises, from the inside out, an optical fiber, a first protective layer for the optical fiber, a first water-blocking layer for the optical fiber, a metallic protective layer for the optical fiber, a second water-blocking layer for the optical fiber, and a second protective layer for the optical fiber; wherein, the metallic protective layer for the optical fiber is a stainless steel layer or an aluminum alloy layer.

[0016] Furthermore, the signal transmission unit includes, from the inside out, a signal center support, multiple signal transmission cores, a signal support, and a signal protective sleeve; the multiple signal transmission cores are arranged in a ring around the signal center support, and a signal support is provided between two adjacent signal transmission cores; each signal transmission core includes multiple second copper conductors and an insulating layer covering the outer periphery of the multiple second copper conductors, and water-blocking adhesive is filled between adjacent second copper conductors.

[0017] Furthermore, the signal protection sleeve comprises, from the inside out, a first water-blocking layer, a metal shielding layer, a second water-blocking layer, and a signal protection layer; wherein, the metal shielding layer is any one of a copper strip structure, a steel strip structure, or a copper wire braided structure.

[0018] Furthermore, the materials of the first water-blocking layer, the second water-blocking layer, the first water-blocking layer of the optical fiber, the second water-blocking layer of the optical fiber, the first water-blocking layer of the signal, and the second water-blocking layer of the signal are all intumescent water-blocking materials. When the intumescent water-blocking material comes into contact with water, it absorbs water and expands to form a sealing layer.

[0019] Furthermore, the materials of the first protective layer, the second protective layer, and the third protective layer are all polyethylene, polypropylene, or polyamide; the materials of the first tensile and torsion armor layer and the second tensile and torsion armor layer are both high-strength steel wire or steel strip.

[0020] The role and effect of invention According to the present invention, the compression- and torsion-resistant submarine cable utilizes a Reuleaux polygonal central support member to form surface contact with the conductor unit, eliminating stress concentration, preventing conductor displacement and insulation layer damage under pressure, and extending cable life. Furthermore, the central support member and the edge support member work together to achieve full surface contact support between each layer, avoiding relative displacement and deformation, forming a synergistic compression- and torsion-resistant overall load-bearing structure. Simultaneously, by setting first and second tensile and torsion-resistant armor layers with opposite braiding directions, a reverse cross-braiding structure is formed, effectively offsetting torque and preventing armor loosening, cable core kinking, and conductor breakage. In addition, the optical fiber unit and signal transmission unit are independently embedded within the edge support member, isolating electromagnetic interference and possessing independent rigid protection (such as a metal protective layer) to resist compression and shearing, ensuring stable signal transmission. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the cross-sectional structure of a pressure- and torsion-resistant submarine cable according to the present invention; Figure 2 This is a schematic diagram of the cross-sectional structure of the optical fiber unit in this invention; Figure 3 This is a schematic diagram of the cross-sectional structure of the signal transmission unit in this invention.

[0022] Explanation of reference numerals in the attached figures: 10. Central support component; 20. Conductor unit; 21. Conductive core; 22. Conductor semi-conductive shielding layer; 23. Main insulation layer; 24. Insulating semi-conductive shielding layer; 25. First semi-conductive water-blocking layer; 26. Metallic shielding layer; 27. Second semi-conductive water-blocking layer; 28. Semi-conductive layer; 30. Edge support component; 40. Optical fiber unit; 41. Optical fiber; 42. First protective layer of optical fiber; 43. First water-blocking layer of optical fiber; 44. Metallic protective layer of optical fiber; 45. Second water-blocking layer of optical fiber; 46. Second protective layer of optical fiber; 50. 51. Signal transmission unit; 52. Signal center support; 53. Signal transmission core; 54. Signal support; 55. Signal protection sleeve; 56. First water-blocking layer; 57. Metal shielding layer; 58. Second water-blocking layer; 59. Signal protection layer; 20. Protective anti-torsion and anti-compression unit; 61. First protective layer; 62. First water-blocking layer; 63. First tensile and torsional armor layer; 64. Second protective layer; 65. Second tensile and torsional armor layer; 66. Second water-blocking layer; 67. Third protective layer. Detailed Implementation

[0023] To make the technical means, creative features, objectives and effects of this invention easy to understand, the invention will be described in detail below with reference to the accompanying drawings.

[0024] like Figures 1 to 3As shown, this embodiment provides a pressure- and torsion-resistant submarine cable suitable for deep-sea environments, used for the simultaneous transmission of power and optical signals.

[0025] like Figure 1 As shown, the compression- and torsion-resistant submarine cable provided in this embodiment includes a central support 10, multiple conductor units 20, multiple edge support units 30, at least one optical fiber unit 40, at least one signal transmission unit 50, and a protective torsion- and compression-resistant unit 60.

[0026] The central support member 10 is located at the center of the cable, and its cross-section is a Reuleaux polygon. In this embodiment, there are three conductor units 20, therefore the central support member 10 is a Reuleaux triangle. Each side of the central support member 10 is a flat or slightly concave arc surface, used to form surface contact with the conductor unit 20. The material of the central support member 10 is any one of rigid engineering plastics (such as polyetheretherketone PEEK), fiberglass, or aluminum alloy. In this embodiment, fiberglass is preferably used for the central support member 10 to balance strength and lightweight.

[0027] Multiple conductor units 20 are arranged around the outer periphery of the central support 10. The inner surface of each conductor unit 20 is in contact with the corresponding edge of the central support 10, forming a stable surface contact. A gap is formed between two adjacent conductor units 20, and a gap support 30 is provided in each gap. The material of the gap support 30 is any one of elastic rubber, polyurethane, or glass fiber composite material. In this embodiment, the gap support 30 is preferably made of polyurethane elastomer to provide good cushioning and support.

[0028] The optical fiber unit 40 and the signal transmission unit 50 are respectively embedded in different edge support members 30. In this embodiment, a total of three edge support members 30 are provided, one of which embeds the optical fiber unit 40, another embeds the signal transmission unit 50, and the third is a solid structure. The shape of the edge support member 30 is adapted to the space between the adjacent conductor unit 20 and the outer protective layer to ensure the compactness of the overall structure.

[0029] The protective anti-torsion and anti-compression unit 60 covers the outer periphery of the conductor unit 20, the edge support member 30, the optical fiber unit 40, and the signal transmission unit 50. The protective anti-torsion and anti-compression unit 60 includes, from the outside to the inside, a first protective layer 61, a first water-blocking layer 62, a first tensile and torsion-resistant armor layer 63, a second protective layer 64, a second tensile and torsion-resistant armor layer 65, a second water-blocking layer 66, and a third protective layer 67.

[0030] The materials of the first protective layer 61, the second protective layer 64, and the third protective layer 67 are all polyethylene (PE), polypropylene (PP), or polyamide (PA). In this embodiment, high-density polyethylene (HDPE) is preferably used for the protective layers to provide excellent water pressure resistance and corrosion resistance.

[0031] Both the first tensile and torsional armor layer 63 and the second tensile and torsional armor layer 65 are made of high-strength materials using a cross-weaving process, and their weaving directions are opposite. In this embodiment, the first tensile and torsional armor layer 63 is woven in a left-hand direction, and the second tensile and torsional armor layer 65 is woven in a right-hand direction. The high-strength material is high-strength steel wire or steel strip. Furthermore, a non-metallic protective layer is provided on the surface of both the first tensile and torsional armor layer 63 and the second tensile and torsional armor layer 65 to ensure the armor layers' effectiveness in deep-sea environments.

[0032] In this embodiment, the armor layer is preferably made of galvanized high-strength steel wire. Through reverse cross-weaving, the two armor layers can mutually cancel out torsional moments, significantly improving the cable's torsional resistance. The non-metallic protective layer is preferably a coating protective layer.

[0033] The first water-blocking layer 62 and the second water-blocking layer 66 are both made of intumescent water-blocking materials. Intumescent water-blocking materials can rapidly absorb water and expand upon contact with it, increasing in volume several times to form a dense sealing layer that prevents moisture from penetrating along the cable's axial direction. In this embodiment, an intumescent water-blocking tape is preferably used as the water-blocking layer.

[0034] like Figure 1 As shown, each conductor unit 20 includes, from the inside out, a conductive core 21, a conductor semiconducting shielding layer 22, a main insulating layer 23, an insulating semiconducting shielding layer 24, a first semiconducting resistive water layer 25, a metal shielding layer 26, a second semiconducting resistive water layer 27, and a semiconducting layer 28.

[0035] The conductive core 21 is made of multiple first copper conductors twisted together, and water-blocking adhesive is filled between adjacent first copper conductors to prevent moisture from penetrating longitudinally along the conductor gaps.

[0036] The main insulation layer 23 is made of any one of cross-linked polyethylene (XLPE), ethylene propylene rubber (EPR), or polyolefin insulating materials. In this embodiment, the main insulation layer 23 is preferably made of cross-linked polyethylene because it has excellent electrical insulation properties and heat resistance.

[0037] Both the conductor semiconducting shielding layer 22 and the insulating semiconducting shielding layer 24 are made of carbon black-filled semiconducting composite material, which is used to uniform the electric field and prevent partial discharge.

[0038] The metal shielding layer 26 can be any one of a copper strip structure, a steel strip structure, or a copper wire braided structure. In this embodiment, the metal shielding layer 26 preferably adopts a copper strip wrapping structure to provide effective electromagnetic shielding.

[0039] The first semiconducting resistive water layer 25 and the second semiconducting resistive water layer 27 are either semiconducting resistive water strips or semiconducting resistive water pastes. In this embodiment, the semiconducting resistive water layer is preferably a semiconducting resistive water strip.

[0040] like Figure 2 As shown, the optical fiber unit 40 includes, from the inside out, an optical fiber 41, a first protective layer 42, a first water-blocking layer 43, a metal protective layer 44, a second water-blocking layer 45, and a second protective layer 46.

[0041] Fiber 41 is a single-mode or multimode fiber used to transmit optical signals.

[0042] The first protective layer 42 and the second protective layer 46 of the optical fiber are made of polypropylene or polyamide materials to provide mechanical protection.

[0043] The first water-blocking layer 43 and the second water-blocking layer 45 of the optical fiber are made of expandable water-blocking materials to ensure the longitudinal water-blocking performance of the optical fiber unit 40.

[0044] The optical fiber metal protective layer 44 is a stainless steel layer or an aluminum alloy layer. In this embodiment, the optical fiber metal protective layer 44 is preferably made of stainless steel tubing to provide independent rigid protection against external extrusion and shear forces.

[0045] like Figure 3 As shown, the signal transmission unit 50 includes, from the inside out, a signal center support 51, multiple signal transmission cores 52, a signal support 53, and a signal protective sleeve 54.

[0046] The signal center support 51 is located at the center of the signal transmission unit 50 and is made of rigid engineering plastic.

[0047] Multiple signal transmission cores 52 are arranged in a ring around the signal center support 51, and a signal support 53 is provided between two adjacent signal transmission cores 52. Each signal transmission core 52 includes multiple second copper conductors and an insulating layer covering the outer periphery of the multiple second copper conductors, and water-blocking adhesive is filled between adjacent second copper conductors.

[0048] The signal support 53 is made of elastic rubber or polyurethane material and is used to fix and buffer the signal transmission core 52.

[0049] The signal protection sleeve 54 comprises, from the inside out, a first water-blocking layer 541, a metal shielding layer 542, a second water-blocking layer 543, and a protective layer 544. The first water-blocking layer 541 and the second water-blocking layer 543 are made of expandable water-blocking material.

[0050] The signal metal shielding layer 542 can be any one of a copper strip structure, a steel strip structure, or a copper wire braided structure. In this embodiment, the signal metal shielding layer 542 preferably adopts a copper wire braided structure to provide efficient electromagnetic shielding and prevent external electromagnetic fields from interfering with the signal transmission core 52. In this embodiment, the signal protection layer 544 is made of polyethylene or polyurethane material.

[0051] In this embodiment, the materials of the first water-blocking layer 62, the second water-blocking layer 66, the first water-blocking layer 43 of the optical fiber, the second water-blocking layer 45 of the optical fiber, the first water-blocking layer 541 of the signal, and the second water-blocking layer 543 of the signal are all expansion-type water-blocking materials (such as expansion-type water-blocking tape or water-blocking powder), ensuring that a continuous longitudinal water-blocking barrier can be formed after the entire cable is damaged at any location.

[0052] The manufacturing method of the compression- and torsion-resistant submarine cable in this embodiment is as follows: First, the central support component 10 is prepared. The glass fiber reinforced composite material is processed into a long strip support component with a Reuleaux triangular cross-section using extrusion molding or injection molding processes.

[0053] Next, conductor unit 20 is prepared. Multiple first copper conductors are stranded together, and water-blocking adhesive is injected during the stranding process to form a conductive core 21. Then, a conductor semiconducting shielding layer 22, a main insulating layer 23, and an insulating semiconducting shielding layer 24 are extruded sequentially. Next, a first semiconducting water-resistant layer 25 is wrapped around it, followed by a longitudinal or wrapping metal shielding layer 26, then a second semiconducting water-resistant layer 27, and finally a semiconducting layer 28 is extruded.

[0054] Next, fiber unit 40 is prepared. Fiber 41 is placed inside a stainless steel tube, filled with water-blocking paste, and a metal protective layer 44 is formed by a drawing process. Then, a first water-blocking layer 43, a first extruded protective layer 42, a second water-blocking layer 45, and a second extruded protective layer 46 are sequentially wrapped around the outside of the stainless steel tube.

[0055] Next, the signal transmission unit 50 is prepared. Multiple second copper conductors are twisted together and an insulating layer is extruded to form a signal transmission core 52. A signal center support 51 is placed in the center, and signal transmission cores 52 are arranged around it, with signal support members 53 filling the gaps. Then, a first water-blocking layer 541, a braided metal shielding layer 542, a second water-blocking layer 543, and an extruded protective layer 544 are sequentially wrapped around it.

[0056] Next, the cable is stranded. A central support 10 is placed at the center, and three conductor units 20 are arranged around the central support 10 at 120° intervals, so that the inner surface of each conductor unit 20 is in contact with the corresponding edge of the central support 10. Side gap supports 30 are placed in the gaps between adjacent conductor units 20, and the optical fiber unit 40 and the signal transmission unit 50 are respectively embedded in two different side gap supports 30. The entire assembly is stranded to form a stable cable core.

[0057] Finally, the anti-torsion and anti-compression unit 60 is wrapped around the outer periphery of the cable core. The third protective layer 67 is extruded in sequence, the second water-blocking layer 66 is wrapped around, the second tensile and torsion armor layer 65 is reverse-cross braided, the second protective layer 64 is extruded, the first tensile and torsion armor layer 63 is reverse-cross braided (the braiding direction is opposite to that of the second tensile and torsion armor layer 65), the first water-blocking layer 62 is wrapped around, and the first protective layer 61 is extruded.

[0058] After completing the above steps, the compression- and torsion-resistant submarine cable of this embodiment is obtained.

[0059] The role and effect of the embodiments The pressure- and torsion-resistant submarine cable of this invention exhibits superior insulation structure compared to traditional cables, remaining undeformed and unbroken even under high-pressure deep-sea environments. Furthermore, the armor layer remains intact and the cable core remains undisturbed under repeated torsional loads. Even after damage to the outer sheath, water penetration distance is effectively controlled to a minimum. Additionally, electromagnetic interference is significantly reduced, signal transmission is stable, and the optical fiber remains undamaged during compression tests. Therefore, this invention successfully solves the problems of pressure resistance, torsion resistance, photoelectric interference, water resistance, and structural integrity in existing technologies, making it suitable for combined power and signal transmission in harsh deep-sea environments.

[0060] The above embodiments are preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention.

Claims

1. A pressure- and torsion-resistant submarine cable, characterized in that, include: The system includes a central support, multiple conductor units, multiple edge support units, at least one optical fiber unit, at least one signal transmission unit, and a protective anti-torsion and anti-compression unit. The central support member is in the shape of a Reuleaux polygon and is located at the center of the cable. The number of sides of the central support member is the same as the number of conductor units. Multiple conductor units are arranged around the outer periphery of the central support member, and a side gap support member is provided between each two adjacent conductor units; The optical fiber unit and the signal transmission unit are respectively embedded in different edge support members; The protective anti-torsion and anti-compression unit covers the outer periphery of the conductor unit, the edge support, the optical fiber unit and the signal transmission unit. The protective anti-torsion and anti-compression unit includes, from the outside to the inside, a first protective layer, a first water-blocking layer, a first tensile and torsion-resistant armor layer, a second protective layer, a second tensile and torsion-resistant armor layer, a second water-blocking layer and a third protective layer.

2. The compression- and torsion-resistant submarine cable according to claim 1, characterized in that, Both the first tensile and torsional armor layer and the second tensile and torsional armor layer are made of high-strength materials through a cross-weaving process, and the weaving directions of the two are opposite.

3. The compression- and torsion-resistant submarine cable according to claim 1, characterized in that, The conductor unit, from the inside out, includes a conductive core, a conductor semiconducting shielding layer, a main insulating layer, an insulating semiconducting shielding layer, a first semiconducting resisting water layer, a metal shielding layer, a second semiconducting resisting water layer, and a semiconducting layer. The conductive core is composed of multiple first copper conductors, and water-blocking adhesive is filled between adjacent first copper conductors. The material of the main insulation layer is any one of cross-linked polyethylene, ethylene propylene rubber, or polyolefin insulation material; Both the conductor semiconducting shielding layer and the insulating semiconducting shielding layer are made of carbon black-filled semiconducting composite material.

4. The compression- and torsion-resistant submarine cable according to claim 3, characterized in that, The metal shielding layer can be any one of a copper strip structure, a steel strip structure, or a copper wire braided structure. The first semiconducting resistive water layer and the second semiconducting resistive water layer are either semiconducting resistive water strips or semiconducting resistive water pastes.

5. The compression- and torsion-resistant submarine cable according to claim 1, characterized in that, The material of the central support member is any one of rigid engineering plastic, fiberglass, or aluminum alloy; the material of the edge support member is any one of elastic rubber, polyurethane, or glass fiber composite material.

6. The compression- and torsion-resistant submarine cable according to claim 1, characterized in that, The optical fiber unit, from the inside out, includes an optical fiber, a first protective layer for the optical fiber, a first water-blocking layer for the optical fiber, a metallic protective layer for the optical fiber, a second water-blocking layer for the optical fiber, and a second protective layer for the optical fiber. The optical fiber metal protective layer is a stainless steel layer or an aluminum alloy layer.

7. The compression- and torsion-resistant submarine cable according to claim 1, characterized in that, The signal transmission unit, from the inside out, includes a signal center support, multiple signal transmission cores, a signal support, and a signal protective sleeve. Multiple signal transmission cores are arranged in a ring around the signal center support, and a signal support is provided between two adjacent signal transmission cores; each signal transmission core includes multiple second copper conductors and an insulating layer covering the outer periphery of the multiple second copper conductors, and water-blocking adhesive is filled between adjacent second copper conductors.

8. The compression- and torsion-resistant submarine cable according to claim 7, characterized in that, The signal protection sleeve comprises, from the inside out, a first water-blocking layer, a metal shielding layer, a second water-blocking layer, and a signal protection layer. The signal metal shielding layer can be any one of a copper strip structure, a steel strip structure, or a copper wire braided structure.

9. The compression- and torsion-resistant submarine cable according to any one of claims 1, 6, or 8, characterized in that, The materials of the first water-blocking layer, the second water-blocking layer, the first water-blocking layer of the optical fiber, the second water-blocking layer of the optical fiber, the first water-blocking layer of the signal, and the second water-blocking layer of the signal are all expansion-type water-blocking materials. When the expansion-type water-blocking material comes into contact with water, it absorbs water and expands to form a sealing layer.

10. The compression- and torsion-resistant submarine cable according to claim 1, characterized in that, The materials of the first protective layer, the second protective layer, and the third protective layer are all any one of polyethylene, polypropylene, or polyamide; Both the first tensile and torsional armor layer and the second tensile and torsional armor layer are made of high-strength steel wire or steel strip.

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