Submarine cable joint box and method of installing the same

Abstract

This invention relates to the field of submarine cable technology, providing a submarine cable splice box and its installation method. The splice box includes two sealing ends, each corresponding to one of the two submarine cables and adapted to be fused with the outer sheath of the cable, so that the sealing ends are sealed to the circumferential surface of the cable; and a sealing cylinder, with its two ends respectively fitted onto the two sealing ends and sealed to them. This splice box fuses the sealing ends with the outer sheath of the cable into a single unit through fusion welding, achieving a seamless connection between the splice box and the cable, greatly improving the sealing performance of the splice box. It reduces the wear and tear of spare parts, lowers the cost of product construction and operation, and simplifies installation. It also avoids irreversible radial shrinkage deformation of the internal insulation and other structures of the cable during the cable's thermal cycling stage due to excessive compression of the sealing ring, thus ensuring the electrical performance of the cable.

Description

Technical Field

[0001] This invention relates to the field of submarine cable technology, and in particular to a submarine cable junction box and its installation method. Background Technology

[0002] Submarine cables, also known as submarine cables or optical cables, are laid in the ocean and are crucial equipment for offshore power or telecommunications transmission. With the development of offshore wind power, seabed oil and gas extraction, and communication technology, the amount of submarine cables laid is increasing year by year. However, problems encountered during the application of submarine cables are also becoming increasingly prominent. During laying or operation, submarine cables are inevitably subjected to tensile forces or other external impacts, such as sand and gravel friction and anchor damage, which can cause damage. When a submarine cable is damaged, it needs to be repaired using splice boxes. Due to production length limitations, long-length submarine cables also require splicing using splice boxes.

[0003] Junction boxes are used not only to restore the electrical performance of submarine cables but also to restore their mechanical properties. However, the harsh underwater environment, especially at great depths, makes ensuring a proper seal for the junction box crucial. In related technologies, junction boxes primarily employ a single mechanical seal method, installing various types of sealing rings between the sealing end cap and the submarine cable. These sealing rings are under compression between the sealing end cap and the cable. Some sealing rings, due to excessive compression, can easily cause extrusion of the cable during thermal cycling, leading to irreversible radial shrinkage deformation of the cable's internal insulation structure, thus affecting the cable's electrical performance and waterproof sealing effect. Summary of the Invention

[0004] This invention provides a submarine cable junction box and its installation method to solve the problem that the sealing method of the submarine cable junction box in the prior art can easily cause compression of the submarine cable, affecting the electrical performance and waterproof sealing effect of the submarine cable.

[0005] This invention provides a submarine cable junction box, comprising:

[0006] Two sealing ends are fitted one-to-one on the two submarine cables and are adapted to be fused with the outer sheath of the submarine cables so that the sealing ends are sealed to the circumferential side of the submarine cables.

[0007] A sealing cylinder, the two ends of which are respectively fitted onto the two sealing ends and sealed to the sealing ends.

[0008] According to the submarine cable junction box provided by the present invention, it further includes:

[0009] Two heat shrink tubing, two sealing ends, and two submarine cables are provided in a one-to-one correspondence. The heat shrink tubing is sleeved on the corresponding submarine cable and the sealing end, and the two ends of the heat shrink tubing are heat-shrinkly connected to the submarine cable and the sealing end, respectively.

[0010] According to the present invention, a submarine cable junction box is provided, wherein the sealing end has a first connecting section and a second connecting section arranged along its axial direction and connected to each other, the inner side of the first connecting section is fused to the outer sheath of the submarine cable, the outer side of the second connecting section is sealed to the sealing cylinder, and the cross-sectional area of ​​the first connecting section is smaller than the cross-sectional area of ​​the second connecting section.

[0011] According to a submarine cable junction box provided by the present invention, the first connecting segment is provided with a tapering section, and the cross-section of the tapering section gradually decreases in the direction away from the second connecting segment.

[0012] According to the present invention, the outer surface of the tapered section of the submarine cable junction box is a conical surface.

[0013] According to a submarine cable junction box provided by the present invention, a plurality of sealing rings are distributed on the outer side of the second connecting section along the axial direction of the sealing end, and the sealing cylinder and the second connecting section are sealed and connected by the sealing rings.

[0014] According to the submarine cable junction box provided by the present invention, it further includes:

[0015] Two connecting flanges are fitted one-to-one on the outside of the two sealing ends and connected to the sealing cylinder by fasteners;

[0016] The outer side of the sealing end is provided with a limiting groove, and a portion of the connecting flange near the sealing end is confined within the limiting groove.

[0017] According to the present invention, a submarine cable junction box is provided, wherein the sealing end is made of a non-metallic organic material suitable for welding with the outer sheath of the submarine cable.

[0018] The present invention also provides a method for installing a submarine cable junction box, comprising:

[0019] Place the two sealing ends onto the two submarine cables to be spliced, and place the sealing cylinder onto either of the submarine cables.

[0020] Fabricate an intermediate joint to connect the two submarine cables;

[0021] Move the sealing cylinder so that its two ends are respectively fitted onto the two submarine cables;

[0022] The two sealing ends are pushed into the two ends of the sealing cylinder respectively, and the two ends of the sealing cylinder are fastened to the two sealing ends one by one using fasteners.

[0023] The sealing end is heated to melt it and fuse it with the outer sheath of the submarine cable.

[0024] According to the present invention, a method for installing a submarine cable splice box includes, before the two sealing ends are respectively fitted onto the two submarine cables to be spliced, the method further includes: fitting two heat shrink tubes respectively onto the two submarine cables to be spliced.

[0025] After heating the sealing end to melt it and fuse it with the outer sheath of the submarine cable, the process further includes:

[0026] Move the heat shrink tubing so that both ends of the heat shrink tubing are respectively fitted onto the corresponding sealing end and the submarine cable;

[0027] The heat shrink tubing is heated to heat shrink and connect it to the sealing end and the submarine cable respectively.

[0028] The submarine cable splice box and its installation method provided by this invention feature two sealing ends, each corresponding to one of the two submarine cables and suitable for fusion welding with the outer sheath of the cables, achieving a sealed connection between the sealing ends and the cables. A sealing cylinder is fitted onto each of the two sealing ends, achieving a sealed connection between the two sealing ends and the sealing cylinder. This submarine cable splice box fuses the sealing ends and the outer sheath of the submarine cable into one unit through fusion welding, achieving a seamless connection between the splice box and the submarine cable, greatly improving the sealing performance of the splice box. It eliminates the need for multiple sizes of sealing rings between the submarine cable and the splice box to accommodate cable tolerances, reducing the consumption of spare parts and lowering the cost of product construction and operation. Installation is simple and can significantly improve construction efficiency. It avoids irreversible radial shrinkage deformation of the internal insulation and other structures of the submarine cable during the cable thermal cycling stage due to excessive compression of the sealing rings, thus ensuring the electrical performance of the submarine cable. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in this invention 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 invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0030] Figure 1 This is a schematic diagram of the installation structure of the submarine cable junction box and the submarine cable provided by the present invention;

[0031] Figure 2 This is a partially enlarged view of the installation structure of the submarine cable junction box and the submarine cable provided by the present invention;

[0032] Figure label:

[0033] 11. Submarine cable; 12. Intermediate joint; 2. Sealing end; 21. First connecting section; 211. Gradient section; 22. Second connecting section; 221. Limiting groove; 3. Sealing cylinder; 4. Heat shrink tubing; 5. Sealing ring; 6. Connecting flange; 7. Fasteners. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0035] In the description of the embodiments of the present invention, it should be noted that, unless otherwise expressly specified and limited, the terms "first" and "second" are used to clearly describe the product components and do not represent any substantial difference.

[0036] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0037] The following is combined with Figure 1 and Figure 2 The present invention describes the submarine cable junction box and its installation method.

[0038] The submarine cable junction box provided in this embodiment of the invention is used to connect two submarine cables 11 that need to be spliced. It can be used for single-phase sealing of submarine cables, sealing of the outer sheath of the entire cable, sealing of submarine optical cables, and can also be extended to waterproof sealing of structures such as land cables.

[0039] like Figure 1 As shown, the submarine cable junction box provided in this embodiment of the invention includes a sealing cylinder 3 and two sealing ends 2. The two sealing ends 2 are fitted one-to-one onto two submarine cables 11 and are adapted to be fused with the outer sheath of the submarine cables 11 so that the sealing ends 2 are sealed to the circumferential side of the submarine cables 11. The two ends of the sealing cylinder 3 are respectively fitted onto the two sealing ends 2 and are sealed to the sealing ends 2.

[0040] It should be noted that after the two submarine cables 11 are connected through the intermediate joint 12, they are then connected through the submarine cable joint box to achieve a seal.

[0041] It is understood that the sealing cylinder 3, the sealing end 2, and the submarine cable 11 are coaxially arranged. The two sealing ends 2 are respectively fused to one end of the two submarine cables 11, so that there is no gap between the sealing end 2 and the corresponding submarine cable 11. The intermediate joint 12 is located inside the sealing cylinder 3, and the two ends of the sealing cylinder 3 are respectively sealed to the two sealing ends 2, thereby achieving the sealing of the connection part of the two submarine cables 11 by the submarine cable joint box.

[0042] Optionally, the sealing end 2 is made of a non-metallic organic material suitable for welding with the outer sheath of the submarine cable 11. For example, if the outer sheath of the submarine cable 11 is made of PE (Polyethylene) or PVC (Polyvinyl chloride), then the sealing end 2 can be made of organic materials such as HDPE (High Density Polyethylene). The sealing end 2 can be heated to melt it and fuse it with the outer sheath of the submarine cable 11, thereby achieving a sealed connection between the submarine cable 11 and the sealing end 2.

[0043] The submarine cable splice box provided in this embodiment of the invention features two sealing ends 2, which are fitted one-to-one onto two submarine cables 11 and are adapted to be fused with the outer sheath of the submarine cables 11, thus achieving a sealed connection between the sealing ends 2 and the submarine cables 11. Two ends of a sealing cylinder 3 are respectively fitted onto the two sealing ends 2, achieving a sealed connection between the two sealing ends 2 and the sealing cylinder 3. This submarine cable splice box fuses the sealing ends 2 and the outer sheath of the submarine cables 11 into one unit through fusion welding, achieving a seamless connection between the splice box and the submarine cables 11, greatly improving the sealing performance of the splice box. It eliminates the need for multiple sizes of sealing rings between the submarine cables 11 and the splice box to accommodate cable tolerances, reducing the consumption of spare parts and lowering the cost of product construction and operation. It also avoids irreversible radial shrinkage deformation of the internal insulation and other structures of the submarine cable during the cable thermal cycling stage due to excessive compression of the sealing rings, thereby ensuring the electrical performance of the submarine cable.

[0044] Compared to the traditional submarine cable junction box sealing method using a sealing ring, where the sealing ring is compressed when pushed into the sealing groove and is difficult to move, making installation time-consuming and labor-intensive, the submarine cable junction box provided in this embodiment of the invention is easy to install and can significantly improve construction efficiency.

[0045] Some embodiments of the present invention provide a submarine cable junction box that further includes two heat shrink tubing 4, with the two heat shrink tubing 4, two sealing ends 2, and two submarine cables 11 arranged in a one-to-one correspondence. The heat shrink tubing 4 is sleeved on the corresponding submarine cable 11 and sealing end 2, and both ends of the heat shrink tubing 4 are heat-shrinkly connected to the submarine cable 11 and sealing end 2, respectively.

[0046] Among them, the heat shrink tubing 4 has heat shrinking properties, which can shrink after being heated to a certain temperature, and is tightly connected to the submarine cable 11 and the sealing end 2, so that the heat shrink tubing 4 is sealed to the submarine cable 11 and the sealing end 2 respectively.

[0047] Understandably, each sealing end 2 has a first end and a second end that are opposite to each other in its axial direction. The inner side of the portion of the sealing end 2 near the first end is fused to the outer sheath of the submarine cable 11, and the outer side is heat-shrinkably connected to the heat-shrink tubing 4. The two ends of the sealing cylinder 3 are respectively fitted onto the outer sides of the portions of the two sealing ends 2 near the second end, and are sealed to the sealing end 2.

[0048] In this embodiment, the sealing end 2 is fused to the outer sheath of the submarine cable 11, thus achieving the first waterproof barrier between the sealing end 2 and the submarine cable 11. By setting two heat-shrink tubing 4, which are fitted onto the outer sides of the corresponding sealing end 2 and submarine cable 11, a second waterproof barrier is achieved for the periphery of the sealing end 2 and submarine cable 11. This embodiment, through these two seals, greatly ensures the reliability of the periphery sealing connection between the sealing end 2 and the submarine cable 11, improving the sealing performance of the submarine cable junction box.

[0049] like Figure 2 As shown, in some embodiments of the present invention, the sealing end 2 has a first connecting section 21 and a second connecting section 22 arranged along its axial direction and connected to each other. The inner side of the first connecting section 21 is fused to the outer sheath of the submarine cable 11, and the outer side of the second connecting section 22 is sealed to the sealing cylinder 3. The cross-sectional area of ​​the first connecting section 21 is smaller than the cross-sectional area of ​​the second connecting section 22.

[0050] It is understood that the first connecting section 21 is connected to the first end of the sealing end 2, and the second connecting section 22 is connected to the second end of the sealing end 2. Both the first connecting section 21 and the second connecting section 22 are annular cylindrical structures. The first connecting section 21 is a thin-walled section to facilitate the heat fusion operation. The second connecting section 22 is a thick-walled section to ensure its structural strength and enable it to reliably connect with the sealing cylinder 3.

[0051] Optionally, both the first connecting segment 21 and the second connecting segment 22 are cylindrical structures.

[0052] Optionally, the first connecting segment 21 is provided with a tapered section 211. In the direction away from the second connecting segment 22, the cross-section of the tapered section 211 gradually decreases. It should be noted that the cross-section of the tapered section 211 is its cross-section perpendicular to the axis of the sealing end 2.

[0053] Understandably, the wall thickness of the tapered section 211 gradually decreases in the direction away from the second connecting section 22 in the first connecting section 21. The tapered section 211 can be located at the end of the first connecting section 21 away from the second connecting section 22, meaning the thin-walled end of the tapered section 211 serves as the first end of the sealing end 2. Alternatively, the tapered section 211 can be located at the end of the first connecting section 21 close to the second connecting section 22, meaning the thin-walled end of the tapered section 211 is connected to the second connecting section 22. The tapered section 211 can also be located in the middle of the first connecting section 21.

[0054] Optionally, the outer surface of the tapered section 211 is a conical surface. Of course, the outer surface of the tapered section 211 can also be other irregular structures, as long as the wall thickness of the tapered section 211 gradually decreases in the direction away from the second connecting section 22. The present invention does not impose specific limitations on this.

[0055] In some embodiments of the present invention, a plurality of sealing rings 5 ​​are distributed along the axial direction of the sealing end 2 on the outer surface of the second connecting section 22, and the sealing cylinder 3 and the second connecting section 22 are sealed together by the sealing rings 5. Specifically, the outer surface of the second connecting section 22 of the sealing end 2 is provided with a plurality of sealing grooves distributed along the axial direction of the sealing end 2, and a sealing ring 5 is embedded in each sealing groove. The sealing end 2 and the sealing rings 5 ​​can be pre-assembled to improve installation efficiency.

[0056] In this embodiment of the invention, the submarine cable splice box uses the sealing end 2 and the heat shrink tubing 4 to achieve a sealed connection between the splice box and the submarine cable 11, and uses the sealing ring 5 to achieve a sealed connection between the sealing end 2 of the splice box itself and the sealing cylinder 3, thereby achieving a waterproof seal for the two spliced ​​submarine cables through three sealing methods.

[0057] The submarine cable junction box provided in this embodiment of the invention also includes two connecting flanges 6, which are fitted one-to-one on the outside of the two sealing ends 2 and connected to the sealing cylinder 3 by fasteners 7. The outer surface of the sealing end 2 is provided with a limiting groove 221, and a portion of the connecting flange 6 near the sealing end 2 is confined within the limiting groove 221.

[0058] Specifically, the sealing cylinder 3 has radially protruding flanges at both ends, and each flange has multiple first mounting holes. The inner portion of the connecting flange 6 near the sealing end 2 is located within the limiting groove 221, while the outer portion away from the sealing end 2 protrudes from the outer surface of the sealing end 2 and has multiple second mounting holes. The multiple first mounting holes and multiple second mounting holes correspond one-to-one. The connecting flange 6 and the sealing cylinder 3 are fastened together by fasteners 7 passing through the first and second mounting holes. The fasteners 7 can be bolts, rivets, or other fastening components.

[0059] Each connecting flange 6 includes a first connecting part and a second connecting part, which are interlocked to form an annular connecting structure fitted onto the sealing end 2. The limiting groove 221 is an annular groove.

[0060] This invention also provides a method for installing a submarine cable junction box, the method comprising the following steps:

[0061] S1, place the two sealing ends 2 onto the two submarine cables 11 to be spliced ​​respectively, and place the sealing cylinder 3 onto any one of the submarine cables 11.

[0062] S2, make the intermediate joint connecting the two submarine cables 11.

[0063] S3, move the sealing cylinder 3 so that both ends of the sealing cylinder 3 are respectively fitted onto the two submarine cables 11.

[0064] S4, push the two sealing ends 2 into the two ends of the sealing cylinder 3 respectively, and fasten the two ends of the sealing cylinder 3 to the two sealing ends 2 one by one with the fasteners 7.

[0065] S5, heat the sealing end 2 to melt the sealing end 2 and fuse it with the outer sheath of the submarine cable 11.

[0066] The installation method of the submarine cable junction box provided in this embodiment of the invention does not require a sealing ring between the submarine cable junction box and the submarine cable 11. By heating the sealing end 2 to melt it and fuse it with the outer sheath of the submarine cable 11, a seamless sealing connection is achieved. The installation operation is simple, time-saving and labor-saving.

[0067] Furthermore, in some embodiments of the present invention, before step S1 described above, in which the two sealing ends 2 are respectively fitted onto the two submarine cables 11 to be spliced, the method further includes the step of: fitting two heat shrink tubes 4 respectively onto the two submarine cables 11 to be spliced.

[0068] After heating and sealing the end 2 as described in step S5 above, melting the end 2 and fusing it with the outer sheath of the submarine cable 11, the process further includes:

[0069] S6, move the heat shrink tubing 4 so that both ends of the heat shrink tubing 4 are respectively fitted onto the corresponding sealing end 2 and the submarine cable 11.

[0070] S7, heat shrink tubing 4 is heated so that heat shrink tubing 4 is heat-shrinkly connected to sealing end 2 and submarine cable 11 respectively.

[0071] In this embodiment, based on the fusion of the sealing end 2 and the submarine cable 11, the heat shrink tubing 4 is heated and shrinks to strengthen the sealing connection between the sealing end 2 and the submarine cable 11, forming a double waterproof barrier between the sealing end 2 and the submarine cable 11, which further improves the waterproof sealing performance. Moreover, the installation and operation are simple, saving time and effort.

[0072] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A cable jointing box for connecting two submarine cables which need to be jointed, characterized in that, include: Two sealing ends are fitted one-to-one on the two submarine cables. The sealing ends are made of non-metallic organic materials suitable for welding with the outer sheath of the submarine cable, and are welded to the outer sheath of the submarine cable by heating and melting, so as to form a seamless sealing connection between the sealing ends and the peripheral side of the submarine cable. A sealing cylinder, wherein both ends of the sealing cylinder are respectively fitted onto the two sealing ends and are sealed to the sealing ends; The sealing end has a first connecting section and a second connecting section that are arranged along its axial direction and connected to each other. The first connecting section is a thin-walled section and the second connecting section is a thick-walled section. The inner side of the first connecting section is fused to the outer sheath of the submarine cable, and the outer side of the second connecting section is sealed to the sealing cylinder. The first connecting section has a tapered section, and the wall thickness of the tapered section gradually decreases in the direction away from the second connecting section.

2. A cable jointing box according to claim 1, characterised in that, Also includes: Two heat shrink tubing, two sealing ends, and two submarine cables are provided in a one-to-one correspondence. The heat shrink tubing is sleeved on the corresponding submarine cable and the sealing end, and the two ends of the heat shrink tubing are heat-shrinkly connected to the submarine cable and the sealing end, respectively.

3. A cable jointing box according to claim 1, characterised in that, The cross-sectional area of ​​the first connecting segment is smaller than that of the second connecting segment.

4. A cable jointing case according to claim 3, characterised in that, In the direction away from the second connecting segment from the first connecting segment, the cross-section of the tapering segment gradually decreases.

5. A cable jointing box according to claim 4, characterised in that, The outer surface of the tapered section is a conical surface.

6. A cable jointing box according to claim 3, characterised in that, Multiple sealing rings are distributed along the axial direction of the sealing end on the outer surface of the second connecting section, and the sealing cylinder and the second connecting section are sealed together by the sealing rings.

7. A cable jointing box according to claim 1, characterised in that, Also includes: Two connecting flanges are fitted one-to-one on the outside of the two sealing ends and connected to the sealing cylinder by fasteners; The outer side of the sealing end is provided with a limiting groove, and a portion of the connecting flange near the sealing end is confined within the limiting groove.

8. A method for installing a submarine cable junction box, characterized in that, include: Place the two sealing ends onto the two submarine cables to be spliced, and place the sealing cylinder onto either of the submarine cables. Fabricate an intermediate joint to connect the two submarine cables; Move the sealing cylinder so that its two ends are respectively fitted onto the two submarine cables; The two sealing ends are pushed into the two ends of the sealing cylinder respectively, and the two ends of the sealing cylinder are fastened to the two sealing ends one by one using fasteners. Heating the sealing end melts it and fuses it with the outer sheath of the submarine cable, so that the inner side of the first connecting section is fused with the outer sheath of the submarine cable, and the outer side of the second connecting section is sealed to the sealing cylinder. The sealing end has a first connecting section and a second connecting section that are arranged along its axial direction and connected to each other. The first connecting section is a thin-walled section and the second connecting section is a thick-walled section. The inner side of the first connecting section is fused to the outer sheath of the submarine cable, and the outer side of the second connecting section is sealed to the sealing cylinder. The first connecting section has a tapered section, and the wall thickness of the tapered section gradually decreases in the direction away from the second connecting section.

9. The method for installing a submarine cable junction box according to claim 8, characterized in that, Before the two sealing ends are respectively fitted onto the two submarine cables to be spliced, the method further includes: fitting two heat shrink tubes respectively onto the two submarine cables to be spliced. After heating the sealing end to melt it and fuse it with the outer sheath of the submarine cable, the process further includes: Move the heat shrink tubing so that both ends of the heat shrink tubing are respectively fitted onto the corresponding sealing end and the submarine cable; The heat shrink tubing is heated to heat shrink and connect it to the sealing end and the submarine cable respectively.

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