Submarine cable flexible splicing method

Abstract

The invention discloses a submarine cable flexible splicing method. The method comprises the following steps of submarine cable placement and alignment, armoring treatment, electric unit connection, optical cable connection, armoring recovery and flange fixation, and outer layer treatment. According to the invention, the overall outer diameter of the submarine cable splicing part is consistent with that of the submarine cable body through the electric unit splicing size recarving design and the embedded layout of the miniaturized optical cable splicing box, so that the continuous and consistent structure is ensured; the matched optical cable splicing box is designed into a small-volume structure and can be directly embedded into a natural gap of the three-core submarine cable, so that volume redundancy is avoided. Original mechanical and electrical performance of the submarine cable is completely reserved, and the submarine cable has good flexibility and bendability and is suitable for lowering of a conventional traction device, the construction process is greatly simplified, dependence on special large-scale equipment is reduced, and submarine cable emergency repair efficiency and scene adaptability are remarkably improved.

Description

Technical Field

[0001] This invention relates to the field of submarine cable splicing technology, and specifically to a flexible splicing method for submarine cables. Background Technology

[0002] In fields such as marine energy development and submarine communication network construction, submarine cables are the core carriers for energy transmission and signal transmission, and their stable operation is crucial to the reliability of marine engineering. However, submarine cables are exposed to complex marine environments for extended periods and are susceptible to failure and breakage due to ocean currents, ship anchoring, and towing by fishing gear. Therefore, submarine cable repair technology has become a key factor in ensuring the operation of marine infrastructure.

[0003] Currently, submarine cable repair commonly employs a combination of prefabricated cable joints and traditional fiber optic splice boxes. Three-core submarine cables are connected via prefabricated electrical joints, and fiber optic signal transmission is restored using independent splice boxes. Both are encased in a large metal shell to ensure strength and protection, while tensile strength is achieved through mechanical anchoring structures connected to the original armor layer of the submarine cable. However, while this solution achieves splicing functionality, it has significant drawbacks: First, its size and weight are excessive. The prefabricated joints and fiber optic splice boxes are much larger than the submarine cable itself. For example, a 220kV submarine cable repair joint can be up to 6 meters long, approximately 0.9 meters in diameter, and weigh as much as 4 tons. This not only requires the use of large-tonnage lifting vessels and large cable-laying machines, increasing repair costs, but also limits its effectiveness in near-shore shallows and in adverse weather conditions, extending the repair cycle. Second, the rigid structure design presents significant problems. The joint as a whole cannot bend with the submarine cable, making it impossible to lower using conventional traction devices. It also requires an additional segmented lifting process, increasing construction complexity. The difficulties and structural damage risks include a sudden change in stiffness at the connection with the flexible submarine cable. If the seabed topography is undulating or the ocean current is large, the submarine cable at both ends of the joint is prone to "lifting off the ground" and being exposed to the ocean current to withstand greater impact and vibration. The risk of mechanical damage from being caught by anchor chains and fishing nets is also increased. Thirdly, the structural design is redundant. The prefabricated joint and the fiber optic splice box are designed independently, and the metal shell needs to accommodate both at the same time. This results in the joint diameter being 3-6 times that of the submarine cable body, further aggravating the volume and weight problems. Moreover, the surface is subjected to greater ocean current resistance during operation, which can easily cause local scouring of the seabed, causing the joint to sink or tilt, affecting the overall stability of the submarine cable.

[0004] In summary, existing submarine cable repair joints, due to their large size, heavy weight, and rigid structure design flaws, cannot meet the requirements of marine engineering for efficient, low-cost, and highly reliable submarine cable repair. Developing a splicing technology that matches the size of the submarine cable, has flexible and bendable characteristics, and takes into account both strength and protection performance has become the key to solving the current technical problems. Summary of the Invention

[0005] To address the aforementioned technical problems, the purpose of this invention is to provide a flexible splicing method for submarine cables, which achieves flexibility and convenience in submarine cable splicing through structural optimization.

[0006] The above-mentioned objective of the present invention is achieved through the following technical solution:

[0007] A flexible splicing method for submarine cables includes the following steps:

[0008] (1) Armor treatment;

[0009] (2) Electrical unit connection; the electrical unit connection includes: conductor processing and welding, inner shielding layer restoration, insulation layer restoration, outer shielding layer restoration, metal shielding layer restoration and outer sheath restoration;

[0010] (3) Optical cable connection; The optical cable connection adopts the tensile-resistant deep-sea cable fiber optic splice box of CN222926897U, and sleeves are added at both ends of the tensile-resistant deep-sea cable fiber optic splice box; The optical cable connection includes: optical cable insertion, optical cable end treatment and fixing, assembly of connecting fiber optic splice box components, fiber optic fusion splicing and fixing, shell assembly and layered heat shrink sealing.

[0011] (4) Armor restoration and flange fixing; the flange is an armor restoration flange, the outer diameter of the armor restoration flange is consistent with the outer diameter of the submarine cable armor, and the thickness is consistent with the diameter of the submarine cable armor wire. The armor restoration flange adopts a butt joint structure, and its butt joint surface is designed as a V-shaped bevel. Both radial ends of the armor restoration flange are provided with cylindrical weld points consistent with the diameter and stranding direction of the submarine cable armor wire. The armor restoration and flange fixing includes: fixing the armor processed in step (1) according to the original submarine cable. Some sections are wound back to their original positions to complete the pre-restoration of the armor. The two parts of the armor restoration flange are fitted onto the splicing area of ​​the submarine cable. The V-shaped bevel of the armor restoration flange is welded to form a complete ring. Then, a bevel is made on the original armor of the submarine cable, and the angle of the original armor is adjusted so that the bevel of the original armor corresponds one-to-one with the cylindrical weld points on the armor restoration flange to form a V-shaped weld area. The cylindrical weld points are then welded and fixed to the original armor.

[0012] This invention utilizes a design that replicates the dimensions of the electrical unit splice and an embedded layout of a miniaturized optical cable splice box to ensure that the overall outer diameter of the submarine cable splice section is consistent with the submarine cable body, thus guaranteeing the continuity and dimensional consistency of the overall structure after splicing. The matching optical cable splice box is designed with a small volume structure, with a diameter of less than 60mm and a length of less than 200mm, allowing it to be directly embedded into the natural gaps of the three-core submarine cable without occupying additional space, effectively avoiding the redundancy problem of connector volume caused by traditional splice boxes. In the armor connection stage, a specially designed high-strength armor restoration flange is used to achieve a stable connection between the armor of the two sections of the submarine cable.

[0013] Through the above design, the flexible splicing of submarine cables of the present invention can completely preserve the original mechanical and electrical properties of the submarine cable, and has good flexibility and bendability. It can be directly lowered to the seabed by conventional traction devices. Compared with traditional submarine cable on-site repair joints, it greatly simplifies the construction process, reduces the dependence on special large equipment, and significantly improves the construction efficiency and scenario adaptability of submarine cable emergency repair.

[0014] Furthermore, the submarine cable includes an optical cable, electrical units, and armor. Specifically, the three-core submarine cable contains three independent electrical units. The optical cable and each electrical unit together form the main functional body of the submarine cable, while the armor is wrapped around the outside to provide mechanical protection and tensile support.

[0015] Furthermore, step (1) includes the steps of laying and aligning the submarine cable before the armor treatment.

[0016] Furthermore, the placement and alignment of the submarine cable includes: placing each end of the submarine cable at a suitable height, ensuring that both ends of the cut submarine cable are clean and dry, and aligning the two ends of the submarine cable in a straight line.

[0017] Further, in step (1), the armoring process includes: peeling the armor of the two ends of the submarine cable to a preset position to expose the structure to be connected below the armor.

[0018] Further, in step (2), the electrical unit includes a conductor, an inner shielding layer, an insulating layer, an outer shielding layer, a metal shielding layer, and an outer sheath.

[0019] Further, in step (2), the conductor processing and welding includes: stripping out conductors of the corresponding size according to the conductor model and then welding them.

[0020] Further, in step (2), the inner shielding layer restoration includes: using a glass polisher to cut a reactive force cone in the transition area between the electrical unit insulation layer and the inner shielding layer, sanding the insulation layer, inner shielding layer and conductor in sequence with sandpaper, and after cleaning, tightly wrapping the conductor surface with semiconducting tape at the overlap of the original inner shielding layer of the electrical unit at a 40%-60% overlap.

[0021] Further, in step (2), the insulation layer restoration includes: cleaning the surface of the electrical unit insulation layer, wrapping it with insulating tape, then wrapping it with heating tape for heating, with the heating tape overlapping the outer shielding layer at both ends by at least 40-60mm, heating to 190-210℃ and then cooling naturally, adjusting the outer diameter of the insulation to the outer diameter required by the process, and then sanding the surface of the insulation layer and the outer shielding layer with sandpaper.

[0022] Further, in step (2), the outer shielding layer restoration includes: wrapping a semiconductive strip around the outer shielding layer, heating it after wrapping, and checking the quality of the outer shielding layer restoration.

[0023] Further, in step (2), the restoration of the metal shielding layer includes: wrapping a semiconducting resistive water tape, wrapping a copper tape with an overlap of 40%-60%, welding the copper wires at both ends to the copper tape, and then wrapping another layer of semiconducting resistive water tape.

[0024] Further, in step (2), the outer sheath restoration includes: wrapping an outer sheath with the same material and thickness as the original outer sheath of the electrical unit, heating it until it adheres to the electrical unit body, and then allowing it to cool naturally.

[0025] Further, after cooling, check the outer sheath to restore its outer diameter and quality. If adjustments are needed, make appropriate adjustments, insert heat shrink tubing and heat it to make the heat shrink tubing fit against the outer surface of the continued outer sheath.

[0026] Further, in step (3), the tensile-resistant deep-sea cable fiber optic splice box includes:

[0027] The main body of the junction box includes a middle box, a cone block, and an outer shell. There are two cone blocks arranged symmetrically, and the two cone blocks are respectively located at both ends of the length direction of the middle box. The outer shell is fitted over the middle box and is fitted over the cone blocks. A large thread sealing structure is provided between the outer shell and the cone blocks. The fiber optic frame is fixedly installed on the middle box.

[0028] The fiber optic frame is fixedly installed inside the splice box body, and the fiber optic frame is used to hold fiber optic heat shrink tubing.

[0029] The small thread sealing structure consists of two symmetrically arranged structures, and the two small thread sealing structures are respectively connected to both ends of the junction box body.

[0030] The armor fastening structure is installed on the main body of the junction box;

[0031] A large thread sealing structure is provided on the body of the junction box, and the large thread sealing structure is used to seal the body of the junction box.

[0032] Furthermore, in step (3), the sleeve and the end of the tensile deep-sea cable fiber optic splice box are detachably connected to ensure that there is no gap between the sleeve and the splice box.

[0033] Furthermore, in step (3), the sleeve and the cone block of the tensile deep-sea cable fiber optic splice box are detachably connected and can be connected and separated by fasteners such as bolts and pins.

[0034] Furthermore, in step (3), the material of the sleeve is the same as the material of the outer shell of the tensile deep-sea cable fiber optic splice box.

[0035] Furthermore, in step (3), the length of the sleeve is 10-30mm to meet the requirements for optical cable installation and fixation.

[0036] Furthermore, in step (3), the inner diameter of the sleeve matches the outer diameter of the optical cable to be connected, ensuring that the optical cable fits tightly after being inserted.

[0037] Furthermore, in step (3), the optical cable includes an outer sheath, a stainless steel protective layer, and an optical fiber.

[0038] Further, in step (3), the optical cable insertion includes: inserting the optical cable into the cone block, sleeve and shell, and reserving a preset length of optical cable.

[0039] Further, in step (3), the optical cable end treatment and fixing includes: stripping the outer sheath and stainless steel protective layer of the optical cable, retaining a preset length of stainless steel protective layer, installing a clamping plate to fix the optical cable, and repeating the above operation on the other end of the optical cable.

[0040] Furthermore, the preset length of the stainless steel protective layer is 20-30mm.

[0041] Further, in step (3), the assembly of the connecting fiber optic splice box component includes: pushing the cone block and sleeve towards the middle box body, and connecting the cone block to the middle box body and the cone block to the sleeve by matching screws.

[0042] Further, in step (3), the fiber optic splicing and fixing includes: splicing the fiber optics, arranging heat shrink tubing on the arc surface of the fiber optic frame through double-sided adhesive layers, wrapping waterproof tape and fixing the fiber optic frame to the fiber optic box, and grouping the fiber optics at both ends for winding, so that the winding direction of each group of fiber optics is consistent with the position direction of the corresponding heat shrink tubing and located below the clip post.

[0043] Furthermore, the heat shrink tubing has 3 layers, with 8 heat shrink tubing in each layer; when the optical cable has 48 cores, the optical fibers at both ends are divided into 2 groups, with 24 optical fibers in each group.

[0044] Further, in step (3), the outer shell assembly includes: moving the outer shell to the intermediate box and connecting the outer shell and the intermediate box with matching screws.

[0045] Further, in step (3), the layered heat shrink seal includes: sequentially installing heat shrink tubes at the sleeve, the cone, and the outer shell, heating to completely shrink each heat shrink tube, with the heat shrink tube at the cone covering the heat shrink tube at the sleeve, and the heat shrink tube at the outer shell covering the heat shrink tube at the cone.

[0046] Furthermore, in step (4), the flange for armor restoration adopts a butt joint structure, which is different from the traditional one-piece flange, and realizes convenient fitting of the armor overlapping area; the V-shaped bevel can increase the welding contact area and improve the welding strength.

[0047] Furthermore, in step (4), after welding is completed, zinc-rich paint is sprayed onto the weld area, and the zinc-rich paint covers the entire weld area to form a zinc strip.

[0048] The zinc strip not only provides heat insulation but also acts as anodizing protection, delaying armor corrosion and extending the service life of the submarine cable.

[0049] Furthermore, in step (4), after the armor is restored and the flange is fixed, an outer layer treatment step is also included; the outer layer treatment includes: wrapping polypropylene (PP) rope around the outer layer of the armor and fixing it with tape.

[0050] Furthermore, the tape is made of polyvinyl chloride (PVC).

[0051] The beneficial effects of this invention are:

[0052] 1. This invention uses a flexible splicing method for submarine cables to replace traditional prefabricated joints. The outer diameter of the spliced ​​electrical unit is completely consistent with that of the original electrical unit of the submarine cable, and it can accurately replicate the electrical and mechanical properties of the submarine cable electrical unit. After the splicing is completed, the overall outer diameter of the spliced ​​part of the submarine cable can be kept consistent with the original submarine cable, which fundamentally solves the problem of excessive volume caused by the size redundancy of traditional prefabricated joints.

[0053] 2. This invention introduces the small optical cable splice box disclosed in patent CN222926897U. The splice box is small in size and compact in structure. It can be directly filled into the natural gap of the three-core submarine cable without occupying additional radial space. It effectively ensures the overall roundness of the submarine cable after splicing and avoids the risk of increased water flow resistance or external snagging caused by local protrusions.

[0054] 3. The flexible splicing of submarine cables of the present invention can completely preserve the original flexible characteristics and weight specifications of the submarine cable. It does not require special large-scale hoisting equipment. The cable laying operation can be directly achieved by conventional cable laying machine, which greatly simplifies the submarine cable maintenance and construction process, reduces equipment investment costs and operation difficulty, and significantly improves the efficiency and scenario adaptability of submarine cable emergency repair. Attached Figure Description

[0055] Figure 1 This is a physical image of a submarine cable repair joint in the existing technology.

[0056] Figure 2 This is a schematic diagram of the optical cable sheathing in Example 1.

[0057] Figure 3 This is a schematic diagram of the single-sided optical cable end treatment and fixation in Example 1.

[0058] Figure 4 This is a schematic diagram of the optical cable end treatment and fixation in Example 1.

[0059] Figure 5 This is a schematic diagram of the assembly of the fiber optic splice box components in Example 1.

[0060] Figure 6 This is a physical image of the fiber optic splicing and fixing completed in Example 1.

[0061] Figure 7 This is a schematic diagram of the outer shell assembly in Example 1.

[0062] Figure 8 This is a schematic diagram of the layered heat shrink seal in Example 1.

[0063] Figure 9 This is a schematic diagram of the flange used for armor restoration in Example 1.

[0064] Figure 10 This is a schematic diagram of armor restoration and flange fixing in Example 1. Detailed Implementation

[0065] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the specification of this invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0066] Current technologies for submarine cable repair generally employ a combination of prefabricated cable connectors and traditional fiber optic splice boxes. These connectors suffer from design flaws such as large size, heavy weight, and rigid structure. (See attached image.) Figure 1 As shown.

[0067] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments described are not intended to limit the present invention.

[0068] Unless otherwise specified, the experimental methods used in the following examples are conventional methods, and the materials and reagents used are commercially available.

[0069] Example 1

[0070] A flexible splicing method for HYJSAYF41-F 38 / 66 3×1600+1×48C type submarine cable includes the following steps:

[0071] (1) Placement and alignment of submarine cable: First, verify on-site whether the working space and installation environment parameters meet the construction requirements. After meeting the requirements, place each end of the submarine cable at a suitable height, ensure that both ends of the cut submarine cable are clean and dry, and align the two ends of the submarine cable in a straight line.

[0072] (2) Armor treatment: peel off the armor of the submarine cables at both ends at a certain position, separate the electrical unit and the optical cable and align them in pairs.

[0073] (3) Electrical unit connection: Conductor processing and welding, inner shielding layer restoration, insulation layer restoration, outer shielding layer restoration, metal shielding layer restoration and outer sheath restoration are carried out in sequence.

[0074] Conductor processing and welding include: stripping conductors of the corresponding size according to the conductor type, cleaning impurities from the conductor surface, and then welding.

[0075] The inner shielding layer restoration includes: using a glass polisher to cut a reactive force cone in the transition area between the electrical unit's insulation layer and the inner shielding layer; sanding the insulation layer, inner shielding layer, and conductor in sequence with sandpaper; cleaning the electrical unit with cleaning paper after sanding; and then tightly wrapping the conductor surface with semiconducting tape at the original inner shielding layer overlap of the electrical unit at a 50% overlap.

[0076] Insulation layer restoration includes: cleaning the surface of the electrical unit insulation layer and checking the cleanliness of the water-tree resistant insulation tape; wrapping the insulation tape with water-tree resistant insulation tape, ensuring that the tape is tightly fitted, the surface is flat, and there are no gaps or wrinkles; wrapping the heating tape with the heating tape overlapping the outer shielding layer at both ends by 50mm; heating to 200℃ and then allowing it to cool naturally; adjusting the outer diameter of the insulation layer to the required outer diameter; ensuring a smooth transition between the outer shielding layer and the insulation layer without steps; and then sanding the surface of the insulation layer and the outer shielding layer with sandpaper to make the surface of the insulation layer smooth and free of obvious scratches and impurities.

[0077] The outer shielding layer restoration process includes: cleaning the surface of the insulation layer and the outer shielding layer, wrapping the outer shielding layer with semiconductive tape, heating it after wrapping, and checking the quality of the outer shielding layer restoration.

[0078] The restoration of the metal shielding layer includes: wrapping a semi-conductive resistive water tape, then wrapping a copper tape with a 50% overlap, reliably soldering the copper wires at both ends to the copper tape with a soldering iron, grinding the solder joints until there are no obvious protrusions or burrs, and then wrapping another layer of semi-conductive resistive water tape.

[0079] The outer sheath restoration includes: wrapping the outer sheath with the same material and thickness as the original outer sheath of the electrical unit, heating it until it adheres to the electrical unit body, and then allowing it to cool naturally.

[0080] (4) Optical cable connection: The tensile deep-sea cable fiber optic splice box of CN222926897U is used, and sleeves are added to both ends of the tensile deep-sea cable fiber optic splice box. The optical cable is inserted, the optical cable end is treated and fixed, the connecting parts are assembled, the optical fiber is fused and fixed, the outer shell is assembled and the layered heat shrink sealing is performed in sequence.

[0081] Optical cable sheathing includes: inserting the optical cable into the cone block, sleeve, and outer shell, leaving sufficient length of optical cable remaining, such as... Figure 2 As shown.

[0082] The fiber optic cable end treatment and fixing includes: stripping the outer sheath and stainless steel protective layer of the fiber optic cable, leaving 25mm of the stainless steel protective layer, and then installing clamping clips to fix the fiber optic cable. Figure 3 As shown; and repeat the above operation on the other end of the optical cable, as follows. Figure 4 As shown.

[0083] The assembly of the fiber optic splice box components includes: pushing a conical block and a sleeve towards the central box body; connecting the conical block to the central box body and the conical block to the sleeve using matching screws, as shown below. Figure 5 As shown.

[0084] Fiber optic splicing and fixing includes: splicing the optical fibers; evenly applying a layer of double-sided adhesive to the curved surface of the fiber optic frame; sequentially arranging eight heat shrink tubing pieces on the double-sided adhesive on the curved surface of the fiber optic frame; applying another layer of double-sided adhesive to the surface of the arranged heat shrink tubing; repeating the above heat shrink tubing arrangement operation to form a three-layer superimposed structure; tightly wrapping waterproof tape from one end of the fiber optic frame to the other end to ensure a firm and secure fit between the heat shrink tubing and the fiber optic frame; installing the two fiber optic frames with the assembled heat shrink tubing at their respective preset positions in the intermediate box; and securing them with screws to ensure a stable and displacement-free connection between the fiber optic frame and the intermediate box; dividing the 48-core optical fibers at each end into two groups of 24 cores each, with 24 heat shrink tubing pieces corresponding to 24 optical fibers; ensuring that the winding direction of each group of optical fibers is consistent with the placement direction of the corresponding heat shrink tubing; and ensuring that each layer of wound optical fiber is located below the clips of the fiber optic frame. Figure 6 As shown.

[0085] The outer casing assembly includes: moving the outer casing to the intermediate housing, and connecting the outer casing and the intermediate housing using matching screws, such as... Figure 7 As shown.

[0086] Layered heat shrink sealing includes: sequentially installing heat shrink tubing at the sleeve, cone, and outer shell; heating with a blowtorch holder to fully shrink each heat shrink tubing, with the heat shrink tubing at the cone covering the heat shrink tubing at the sleeve, and the heat shrink tubing at the outer shell covering the heat shrink tubing at the cone. Figure 8 As shown.

[0087] (5) Armor restoration and flange fixing; the flange is an armor restoration flange, the outer diameter of which is consistent with the outer diameter of the submarine cable armor, and the thickness is consistent with the diameter of the submarine cable armor wire. The armor restoration flange adopts a butt joint structure, and its butt joint surface is designed with a V-shaped bevel. Both radial ends of the armor restoration flange are provided with cylindrical weld points that are consistent with the diameter and stranding direction of the submarine cable armor wire, ensuring that the armor wire and the flange are completely matched during armor restoration. The structural diagram of the armor restoration flange is shown below. Figure 9As shown; the armor restoration and flange fixing includes: winding the armor processed in step (2) back to its original position according to the original pitch of the submarine cable to complete the armor pre-restoration; fitting the two parts of the armor restoration flange onto the splicing area of ​​the submarine cable; welding the V-shaped bevel of the armor restoration flange with argon arc welding to form a complete ring on the two parts of the armor restoration flange; then making a bevel on the original armor (i.e., the armor wire body) of the submarine cable; adjusting the angle of the original armor so that the bevel of the original armor corresponds one-to-one with the cylindrical weld points on the armor restoration flange to form a V-shaped weld area; welding the cylindrical weld points to the original armor with argon arc welding to fix them. The schematic diagram of armor restoration and flange fixing is shown below. Figure 10 As shown. After welding, zinc-rich paint is sprayed onto the weld area, covering the entire weld area to form a zinc strip.

[0088] (6) Outer layer treatment: Wrap PP rope around the outer layer of the armor and secure it with tape.

[0089] After the flexible splicing of the submarine cable is completed, the outer diameter of the spliced ​​section is consistent with that of the main cable, and the overall tensile strength is 155kN, which can meet the requirements of working conditions at a water depth of 100 meters. The spliced ​​section has waterproof performance at a water depth of 100 meters, and its electrical performance is consistent with that of the main cable, possessing the same application capabilities as the HYJSAYF41-F 38 / 663×1600+1×48C submarine cable.

[0090] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art should understand that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A flexible splicing method for submarine cables, characterized in that, Includes the following steps: (1) Armor treatment; (2) Electrical unit connection; the electrical unit connection includes: conductor processing and welding, inner shielding layer restoration, insulation layer restoration, outer shielding layer restoration, metal shielding layer restoration and outer sheath restoration; (3) Optical cable connection; The optical cable connection adopts the tensile-resistant deep-sea cable fiber optic splice box of CN222926897U, and sleeves are added at both ends of the tensile-resistant deep-sea cable fiber optic splice box; The optical cable connection includes: optical cable insertion, optical cable end treatment and fixing, assembly of connecting fiber optic splice box components, fiber optic fusion splicing and fixing, shell assembly and layered heat shrink sealing. (4) Armor restoration and flange fixing; the flange is an armor restoration flange, the outer diameter of the armor restoration flange is consistent with the outer diameter of the submarine cable armor, and the thickness is consistent with the diameter of the submarine cable armor wire. The armor restoration flange adopts a butt joint structure, and its butt joint surface is designed as a V-shaped bevel. Both radial ends of the armor restoration flange are provided with cylindrical weld points consistent with the diameter and stranding direction of the submarine cable armor wire. The armor restoration and flange fixing includes: fixing the armor processed in step (1) according to the original submarine cable. Some sections are wound back to their original positions to complete the pre-restoration of the armor. The two parts of the armor restoration flange are fitted onto the splicing area of ​​the submarine cable. The V-shaped bevel of the armor restoration flange is welded to form a complete ring. Then, a bevel is made on the original armor of the submarine cable, and the angle of the original armor is adjusted so that the bevel of the original armor corresponds one-to-one with the cylindrical weld points on the armor restoration flange to form a V-shaped weld area. The cylindrical weld points are then welded and fixed to the original armor.

2. The flexible splicing method for submarine cables according to claim 1, characterized in that, In step (1), the process before armoring includes the steps of laying and aligning the submarine cable; the armoring process includes: peeling off the armor of the submarine cables at both ends to a preset position.

3. The flexible splicing method for submarine cables according to claim 1, characterized in that, In step (2), the conductor processing and welding includes: stripping the conductor of the corresponding size according to the conductor model and then welding it; the inner shielding layer restoration includes: using a glass precision cutter to cut a reactive force cone in the transition area between the electrical unit insulation layer and the inner shielding layer, sanding the insulation layer, inner shielding layer and conductor in sequence with sandpaper, and after cleaning, using semiconducting tape to tightly wrap the conductor surface at the overlap of the original inner shielding layer of the electrical unit at a 40%-60% overlap.

4. The flexible splicing method for submarine cables according to claim 1, characterized in that, In step (2), the insulation layer restoration includes: cleaning the surface of the electrical unit insulation layer, wrapping it with insulating tape, then wrapping it with heating tape for heating, with the heating tape overlapping the outer shielding layer at both ends by at least 40-60mm, heating to 190-210℃ and then cooling naturally, adjusting the outer diameter of the insulation to the outer diameter required by the process, and then sanding the surface of the insulation layer and the outer shielding layer with sandpaper; the outer shielding layer restoration includes: wrapping a semiconductive tape around the outer shielding layer, heating it after wrapping, and checking the quality of the outer shielding layer restoration.

5. The flexible splicing method for submarine cables according to claim 1, characterized in that, In step (2), the restoration of the metal shielding layer includes: wrapping a semiconducting resistive water tape, wrapping a copper tape with an overlap of 40%-60%, welding the copper wires at both ends to the copper tape, and then wrapping another layer of semiconducting resistive water tape; the restoration of the outer sheath includes: wrapping an outer sheath with the same material and thickness as the original outer sheath of the electrical unit, heating it until it adheres to the electrical unit body, and then cooling it naturally.

6. The flexible splicing method for submarine cables according to claim 1, characterized in that, In step (3), the optical cable insertion includes: inserting the optical cable into the cone block, sleeve and shell, and leaving a preset length of optical cable; the optical cable end treatment and fixing includes: stripping the outer sheath and stainless steel protective layer of the optical cable, leaving a preset length of stainless steel protective layer, installing a pressure plate to fix the optical cable, and repeating the above operation on the other end of the optical cable.

7. The flexible splicing method for submarine cables according to claim 1, characterized in that, In step (3), the assembly of the connecting fiber optic splice box component includes: pushing the cone block and sleeve towards the middle box body, and connecting the cone block to the middle box body and the cone block to the sleeve by matching screws.

8. The flexible splicing method for submarine cables according to claim 1, characterized in that, In step (3), the fiber optic splicing and fixing includes: splicing the fiber optics, arranging heat shrink tubing on the arc surface of the fiber optic frame through double-sided adhesive layers, wrapping waterproof tape and fixing the fiber optic frame to the fiber optic box, and grouping the fibers at both ends for winding, so that the winding direction of each group of fibers is consistent with the position direction of the corresponding heat shrink tubing and located below the clip.

9. The flexible splicing method for submarine cables according to claim 1, characterized in that, In step (3), the outer shell assembly includes: moving the outer shell to the intermediate box and connecting the outer shell and the intermediate box with matching screws; the layered heat shrink sealing includes: sequentially installing heat shrink tubes at the sleeve, the cone, and the outer shell, heating to make each heat shrink tube completely shrink, and the heat shrink tube at the cone covers the heat shrink tube at the sleeve, and the heat shrink tube at the outer shell covers the heat shrink tube at the cone.

10. The flexible splicing method for submarine cables according to claim 1, characterized in that, In step (4), after welding is completed, zinc-rich paint is sprayed onto the welded area, and the zinc-rich paint covers the entire welded area to form a zinc strip; after the armor is restored and the flange is fixed, the outer layer treatment step is also included; the outer layer treatment includes: wrapping polypropylene rope around the outer layer of the armor and fixing it with tape.

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