Modular dual-cable parallel system based on existing bend limiters

Abstract

This invention provides a modular dual-cable parallel system based on existing bending limiters, comprising two core components: a modular dual-cable parallel connection device for single-cable bending limiters and a dual-cable integrated center tube clamp. The modular connection device adopts an interlocking rigid structure with two independent internal channels, capable of integrating two sets of single-cable bending limiters or being used independently. The dual-cable integrated center tube clamp consists of a bending limiter connecting transition section, a dual-cable progressive center tube convergence ring, a dual-cable parallel center tube conical sleeve, and a backlash ring, achieving reliable fixation of the dual cables in parallel transition and within the J-tube. This invention achieves synchronized dual-cable bending through modular design, improving construction efficiency by over 40%; it is compatible with existing single-cable bending limiters, reducing modification costs; it precisely controls the spacing between the dual cables, avoiding collision risks; and it simplifies the dual-cable tower climbing process, requiring only a single J-tube insertion operation, making it particularly suitable for submarine cable laying operations in high-capacity flexible DC transmission projects.

Description

Technical Field

[0001] This invention belongs to the technical field of submarine cable laying equipment, specifically relating to a modular dual-cable parallel system and a central tube clamp integrated device based on existing bending limiters, particularly for the construction needs of synchronous access to the booster station for positive and negative dual cables in ±200kV and above flexible DC transmission projects. Background Technology

[0002] In deep-sea flexible DC transmission projects, the construction of dual-cable parallel submarine submersibles faces significant technical challenges at substations. Traditional split-installation methods require separate handling of the two cables, leading to the following prominent issues during construction:

[0003] 1. Existing single-cable bending limiters can only be installed in series independently. In the case of parallel operation of two submarine cables, they need to be installed sequentially, which cannot adapt to the parallel operation of two cables, resulting in low efficiency of repetitive work.

[0004] 2. There is a large stock of existing single-cable bending limiters, but their structural design cannot directly meet the requirements of dual-cable parallel operation.

[0005] 3. If two independently installed cables are close together, in addition to the inconvenience of construction, the relative positions of the two submarine cables may change under the influence of tidal currents and scouring effects, causing safety hazards.

[0006] 4. When installed separately, the dynamic offset of the two cables is large. If the two cables are inserted into the same J-shaped pipe, the cumulative wear at the entrance of the J-shaped pipe will increase significantly.

[0007] 5. Temporary binding construction measures are difficult to solve reliability problems and are prone to loosening when two cables pass through facilities such as J-shaped pipes simultaneously.

[0008] The solutions currently used in the industry have obvious flaws:

[0009] 1. Split-type installation requires two J-shaped pipe threading operations, increasing construction time by more than 40%;

[0010] 2. The binding device cannot accurately control the spacing between the two cables, causing the cables to collide at the entrance of the J-tube;

[0011] 3. Traditional center tube clamps are only suitable for single-cable structures, requiring two tube insertions or the use of two independent J-type tubes to accommodate submarine cables. Temporary binding cannot achieve balanced stress distribution in dual-cable systems.

[0012] In the prior art, patent document (CN107294043A) discloses a flexible protection device for a single submarine cable, including a J-tube, a central clamp, and a bending limiter. However, this device can only constrain a single submarine cable individually, requiring two separate installations in a dual-cable parallel scenario, resulting in repetitive work and low efficiency. Furthermore, its central clamp is a single-cable design, which cannot achieve synchronous positioning of the two cables, making it susceptible to relative displacement of the cables due to tidal currents, increasing the risk of wear. Patent document (CN113497432A) discloses a single-cable bending limiter with a monitoring cable, which protects the monitoring cable by rotating the limiter, but it is still limited to a single-cable structure and cannot solve the problems of spacing control and synchronous bending when two cables are running in parallel. In addition, this device does not involve a dual-cable integrated clamp, which cannot adapt to the requirement of two cables passing through the same J-tube, easily leading to cable collision and accelerated wear at the entrance of the J-tube.

[0013] Therefore, there is an urgent need to develop a modular connection device that can integrate traditional submarine cable bending limiters and be integrated through a special central tube clamp to solve the above problems. Summary of the Invention

[0014] This invention proposes a modular dual-cable parallel system based on existing bend limiters. This system fully utilizes existing bend limiters used on single submarine cables, connecting two independent bend limiters through an innovative dual-cable parallel modular connection device. This allows two independent submarine cables to be integrated into the dual-cable parallel system, simultaneously providing bend radius constraint protection for two parallel-laid tower-cable cables. Furthermore, a dual-cable integrated central tube clamp integrates the two loops of submarine cables into a single clamp. This system allows two submarine cables to pass through the same tower-cable J-tube simultaneously, simplifying the tower-climbing construction of dual-loop submarine cables, which originally required two operations, into a single operation. This significantly shortens the construction cycle and effectively reduces the construction difficulty of laying dual-loop submarine cables in parallel.

[0015] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0016] A modular dual-cable parallel system based on existing bend limiters includes a single-cable bend limiter, a dual-cable parallel modular connection device for the single-cable bend limiter, and a dual-cable integrated central tube clamp. The dual-cable parallel modular connection device for the single-cable bend limiter adopts an interlocking rigid integrated structure with two independent channels built in, integrating and connecting two sets of single-cable bend limiters arranged side by side. The dual-cable integrated central tube clamp is connected to the front end of the dual-cable parallel modular connection device for the single-cable bend limiter, and is used to accommodate two-loop submarine cables and realize the transition from split-line to parallel.

[0017] Furthermore, the interlocking rigid integrated structure of the single-cable bending limiter using a dual-cable parallel modular connection device adopts a fixed bolt connection, which integrates and connects the two sets of single-cable bending limiters arranged side by side, and also serves as a parallel connector.

[0018] Furthermore, the single-cable bending limiter uses a dual-cable parallel modular connection device as an independent single-section bending limiter, which can be used independently without the single-cable bending limiter.

[0019] Furthermore, the dual-cable integrated central tube clamp consists of a bending limiter connecting transition section, a dual-cable progressive central tube convergence ring, a dual-cable parallel central tube conical sleeve, and a backlash prevention ring; the bending limiter connecting transition section serves as a connecting node to connect the bending limiter and the clamp body, ensuring the overall rigidity and integrity of the system.

[0020] Furthermore, the bending limiter connecting transition section adopts a two-piece symmetrical structure, with an internal cable shaping bracket for constraining, shaping and accommodating the submarine cable.

[0021] Furthermore, the inner diameter of the dual-cable progressive central tube gathering ring gradually decreases along the cable travel direction to gradually gather the distance between the two cables, ensuring that the cables are brought together at the end of the central tube clamp.

[0022] Furthermore, the dual-cable parallel central tube conical sleeve adopts a left-right split structure, which is spliced ​​by bolts. The inside of the conical sleeve is provided with a cable shaping bracket for fixing and shaping the position and spacing of the cables.

[0023] Furthermore, the dual-cable progressive central tube convergence ring has a hollow cavity that can accommodate two submarine cables, and is used to connect the bend limiter connecting transition section and the dual-cable parallel central tube tapered sleeve.

[0024] Furthermore, the anti-reverse ring adopts an upper and lower two-set structure, which is fixed in the mounting groove of the tapered sleeve of the double-cable parallel center tube by fixing bolts, so as to fix the double-cable integrated center tube clamp as a whole in the J-shaped tube.

[0025] Furthermore, the tapered sleeve of the dual-cable parallel central tube, in conjunction with the anti-reverse ring installed on the periphery of the tapered sleeve, fixes the two submarine cables passing through the tube in a fixed position inside the J-shaped tube.

[0026] The beneficial effects of this invention include:

[0027] 1. The modular structure and segmented design enable synchronized bending of the two cables, eliminating repetitive work in traditional separate installation and improving construction efficiency by more than 40%.

[0028] 2. Compatible with existing single-cable bending limiters, enabling efficient resource reuse and reducing additional material input.

[0029] 3. Built-in dual-channel and progressive central tube convergence ring precisely control the spacing between the two cables, avoiding the risk of collision at the J-tube inlet and turbulence.

[0030] 4. The terminal integrated central tube clamp, combined with the conical sleeve shaping bracket, enables two submarine cables to be fixed simultaneously in a single J-shaped tube, solving the problem of loosening of temporary bindings and significantly improving system reliability.

[0031] 5. The integrated design simplifies the process of climbing dual cables to the tower, requiring only a single J-shaped pipe threading operation, which greatly reduces the construction difficulty and cycle, and is suitable for ±200kV and above flexible DC transmission projects. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the assembly of a dual-cable rigid integrated submarine cable bending limiter and central tube clamp system.

[0033] Figure 2 Three-view diagram of a dual-cable parallel modular connection device for a single-cable bending limiter;

[0034] Figure 3 This is a structural breakdown and assembly drawing of a dual-cable parallel modular connection device for a single-cable bending limiter.

[0035] Figure 4 This is a schematic diagram of a dual-cable parallel modular connection device for a single-cable bending limiter used in conjunction with a single-cable bending limiter.

[0036] Figure 5 This is a schematic diagram of the structure of the dual-cable integrated central tube clamp of the present invention.

[0037] Figure 6 yes Figure 5 Exploded view;

[0038] Figure 7 This is a schematic diagram of the bending limiter connection transition section structure in the dual-cable integrated central tube clamp of the present invention.

[0039] Figure 8 This is a schematic diagram of the dual-cable progressive central tube convergence ring structure in the dual-cable integrated central tube clamp of the present invention.

[0040] Figure 9 This is a schematic diagram of the dual-cable parallel central tube conical sleeve structure in the dual-cable integrated central tube clamp of the present invention.

[0041] Figure 10 This is a schematic diagram of the anti-reverse ring structure in the dual-cable integrated central tube clamp of the present invention.

[0042] Figure 11 This is a schematic diagram of the installation of components in a modular dual-cable parallel system and a central tube clamp integrated device based on an existing bend limiter.

[0043] Figures 12-13 Schematic diagram of a modular dual-cable parallel system and a central tube clamp integrated device based on existing bend limiters Detailed Implementation

[0044] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0045] like Figure 1 As shown, the modular dual-cable parallel system and central tube clamp integrated device based on existing bending limiters of the present invention consists of three key components: a dual-cable parallel modular connection device 100 for a single-cable bending limiter, a dual-cable integrated central tube clamp 200, and a single-cable bending limiter 600.

[0046] like Figure 2 , 3 As shown in Figure 4, the dual-cable parallel modular connection device 100 for the single-cable bending limiter adopts an interlocking rigid integrated structure, connected by fixing bolts 300. It has two built-in independent channels, enabling the integration and connection of two sets of parallel-arranged single-cable bending limiters 600, and also functions as a parallel connector. This device also functions as an independent single-section bending limiter, and can be used independently of the single-cable bending limiter 600 when necessary, ensuring that the two cables maintain synchronous movement during bending and avoiding relative displacement.

[0047] like Figure 5 , 6 As shown, the dual-cable integrated center tube clamp 200 consists of a bending limiter connecting transition section 210, a dual-cable progressive center tube convergence ring 220, a dual-cable parallel center tube conical sleeve 230, and a backstop ring 240.

[0048] like Figure 7 As shown, the bending limiter connecting transition section 210 adopts a two-piece symmetrical structure, with a space for accommodating the submarine cable 400 and a cable shaping bracket 211 inside the transition section. It is fixed by fixing bolts 300. It serves as a connection node to connect the dual-cable parallel modular connection device 100 for the single-cable bending limiter to the clamp body, ensuring the overall rigidity and integrity of the system.

[0049] like Figure 8 As shown, the dual-cable progressive central tube coiling ring 220 has a hollow cavity that can accommodate two submarine cables 400 and serves to connect the bend limiter connecting transition section 210 and the dual-cable parallel central tube tapered sleeve 230. At the same time, the dual-cable progressive central tube coiling ring 220 gradually coils the distance between the two cables to ensure that the cables are brought together at the end of the dual-cable integrated central tube clamp 200.

[0050] like Figure 9As shown, the conical sleeve 230 of the dual-cable parallel central tube adopts a combination structure of two pieces on the left and right sides, which are connected by fixing bolts 300. It is hollow inside and is equipped with a cable shaping bracket 231 inside the conical sleeve, which is used to fix and shape the position and spacing of the cables, and finally make the two separate submarine cables 400 completely close at the outlet position of the conical sleeve 230 of the dual-cable parallel central tube.

[0051] like Figure 10 As shown, the anti-reverse ring 240 adopts an upper and lower two-set design, and is fixed in the mounting groove of the tapered sleeve 230 of the double-cable parallel center tube by fixing bolts 300, which serves to fix the double-cable integrated center tube clamp 200 as a whole in the J-shaped tube 500.

[0052] like Figure 11 , 12 As shown in Figure 13, under normal circumstances, two parallel submarine cables 400 require the installation of two separate sets of bending limiters and center tube clamps to pass through two separately installed J-shaped pipes 500 to reach the top of the platform. The construction steps are cumbersome. However, when using a modular dual-cable parallel system based on existing bending limiters and a center tube clamp integrated device, the entire modular dual-cable parallel system based on existing bending limiters and a center tube clamp integrated device can accommodate two submarine cables 400 at once, so that the work of passing through the J-shaped pipes 500 can be completed in one go, which greatly reduces the construction difficulty and cycle.

Claims

1. A modular dual-cable parallel system based on existing bend limiter, characterized by, This includes a single-cable bend limiter, a dual-cable parallel modular connection device for the single-cable bend limiter, and a dual-cable integrated center tube clamp. The dual-cable parallel modular connection device for the single-cable bend limiter adopts an interlocking rigid integrated structure with two independent internal channels to integrate and connect two sets of single-cable bend limiters arranged side-by-side. The dual-cable integrated center tube clamp is connected to the front end of the dual-cable parallel modular connection device for the single-cable bend limiter, used to accommodate two-circuit submarine cables and achieve separate arrangement. Parallel transition; the single-cable bending limiter uses a double-cable parallel modular connection device with an interlocking rigid integrated structure connected by fixed bolts, integrating and connecting two sets of single-cable bending limiters arranged side by side, which also serves as a parallel connector; the double-cable integrated center tube clamp consists of a bending limiter connecting transition section, a double-cable progressive center tube convergence ring, a double-cable parallel center tube conical sleeve, and a backlash ring; the bending limiter connecting transition section serves as a connection node, used to connect the bending limiter and the clamp body, ensuring the overall rigidity and integrity of the system; the inner diameter of the double-cable progressive center tube convergence ring gradually decreases along the cable travel direction, used to gradually converge the spacing between the two cables, ensuring that the cables are joined together at the end of the center tube clamp; the double-cable parallel center tube conical sleeve adopts a left and right split structure, spliced ​​by bolts, and has an internal cable shaping bracket for fixing and shaping the cable position and spacing.

2. The modular dual-cable parallel system based on existing bend limiter of claim 1, wherein, The single-cable bending limiter uses a dual-cable parallel modular connection device as an independent single-section bending limiter, which can be used independently without the single-cable bending limiter.

3. The modular dual-cable parallel system based on an existing bend limiter according to claim 1, characterized in that, The bending limiter connecting transition section adopts a two-piece symmetrical structure, with an internal cable shaping bracket for constraining, shaping and accommodating the submarine cable.

4. The modular dual-cable parallel system based on an existing bend limiter according to claim 1, characterized in that, The dual-cable progressive central tube convergence ring has a hollow cavity that can accommodate two submarine cables and is used to connect the bend limiter connecting transition section and the dual-cable parallel central tube tapered sleeve.

5. The modular dual-cable parallel system based on an existing bend limiter according to claim 1, characterized in that, The anti-reverse ring adopts an upper and lower two-set structure, which is fixed in the mounting groove of the tapered sleeve of the double cable parallel center tube by fixing bolts, and is used to fix the double cable integrated center tube clamp as a whole in the J-shaped tube.

6. The modular dual-cable parallel system based on an existing bend limiter according to claim 1, characterized in that, The tapered sleeve of the dual-cable parallel central tube, in conjunction with the anti-reverse ring installed on the periphery of the tapered sleeve, fixes the two submarine cables passing through the tube in a fixed position inside the J-shaped tube.

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