Protection device for a suspended submarine cable

Abstract

The application relates to a protection device applied to a suspension submarine cable, which comprises a plurality of sheath assemblies, the sheath assemblies are sequentially distributed along the length direction of the submarine cable, each sheath assembly comprises two detachably connected sheath bodies, the submarine cable is clamped between the two sheath bodies, a continuous undulating wave structure is arranged on the outer wall of the sheath body, the wave line corresponding to the wave structure extends along the length direction of the submarine cable, and the wave line corresponding to the wave structure undulates along the radial direction of the submarine cable. The undulating outer wall of the sheath body can force the seawater to generate a phase difference on different sections, thereby destroying the correlation of the Karman vortex street in the axial direction of the submarine cable, making the vortex unable to synchronously fall off, and further inhibiting vortex-induced vibration. While realizing the inhibition of the vortex-induced vibration, the overall weight of the protection device can be reduced, the fluid resistance can be reduced, the submarine cable can avoid bearing greater gravity load and the drag force of the sea current, and the installation stability of the submarine cable can be improved.

Description

Technical Field

[0001] This invention relates to the field of submarine cable protection technology, and in particular to a protection device for suspended submarine cables. Background Technology

[0002] Submarine cables, as core infrastructure connecting offshore wind power, transoceanic communications, island power grids, and deep-sea oil and gas development, directly impact the stability of energy transmission and information exchange. Submarine cables face complex marine environments over extended periods. For example, under the influence of ocean currents and waves, cables in suspended sections are prone to vortex-induced vibrations. Alternating detached vortices can cause structural fatigue damage and breakage, seriously threatening the safe operation of the cable. Related technologies typically install protective devices on suspended sections of the cable. These devices include clamps for fixing to the cable and spiral plates mounted on the clamps. The spiral plates are used to cut through ocean currents and reduce vortex-induced vibrations. However, the large number of spiral plates not only increases the weight of the protective device itself but also increases fluid resistance, increasing the gravity and drag force on the cable from ocean currents, thus affecting the cable's installation stability. Summary of the Invention

[0003] The purpose of this invention is to provide a protective device for suspended submarine cables that can effectively suppress vortex-induced vibration, reduce the overall weight and fluid resistance of the device, and improve the installation stability of the submarine cable.

[0004] To achieve this objective, the present invention adopts the following technical solution: A protective device for a suspended submarine cable is provided, comprising multiple sheath assemblies arranged sequentially along the length of the submarine cable. Each sheath assembly includes two detachably connected sheath bodies, with the submarine cable clamped between the two sheath bodies. The outer wall of each sheath body is provided with a continuous undulating wave structure, the wave line corresponding to the wave structure extending along the length of the submarine cable and undulating along the radial direction of the submarine cable.

[0005] In one embodiment, along the width direction of the sheath body, the sheath body includes an arc-shaped portion and extension portions disposed at both ends of the arc-shaped portion. The arc-shaped portion is provided with an arc-shaped groove for accommodating the submarine cable. The wave structure is disposed on the side of the arc-shaped portion opposite to the arc-shaped groove. The extension portions of the two sheath bodies located on the same side of the submarine cable are attached to each other and detachably connected by fasteners.

[0006] In one embodiment, the extension is configured as a corrugated plate structure.

[0007] In one embodiment, an elastic pad is sandwiched between two extensions located on the same side of the submarine cable in the sheath assembly.

[0008] In one embodiment, a first flexible pad is sandwiched between the arcuate portion and the submarine cable; and / or, a second flexible pad is laid on the surface of the wave structure.

[0009] In one embodiment, along the length of the submarine cable, one end of the sheath body is provided with a plug-in portion, and the other end is provided with a plug-in groove. In two adjacent sheath assemblies, the plug-in portion is inserted into the plug-in groove.

[0010] In one embodiment, the sheath assembly further includes a sleeve fitted around the periphery of the submarine cable. The sleeve includes two detachably connected semi-cylindrical bodies, with the submarine cable sandwiched between the two semi-cylindrical bodies. Two sheath bodies surround the periphery of the sleeve and are rotatable relative to the sleeve.

[0011] In one embodiment, one of the sheath body and the sleeve is provided with a limiting groove, and the other is provided with a limiting part. The limiting part is inserted into the limiting groove and can slide along the length direction of the limiting groove.

[0012] In one embodiment, the sleeve is provided with a plurality of limiting grooves, which are spaced apart along the length of the sleeve.

[0013] In one embodiment, one end of the sleeve extends along its length to the outside of the sheath body, and the limiting groove is provided on the sleeve located outside the sheath body. In two adjacent sheath assemblies, the limiting groove located outside the sheath body in one sheath assembly is used to insert with the limiting part on the sheath body in the other sheath assembly.

[0014] The advantages of this invention compared to the prior art are: This invention discloses a protective device for suspended submarine cables. It clamps the submarine cable using two detachably connected sheath bodies, facilitating the installation of the sheath bodies onto the cable. A wave structure is formed on the outer wall of the sheath body, with the wave line extending along the length of the cable, creating radial undulations. When seawater radially impacts the cable, the undulating outer wall significantly alters the flow field structure. This undulating outer wall forces a phase difference in the seawater at different cross-sections, disrupting the correlation of the Karman vortex street along the cable's axis, preventing vortices from detaching synchronously, and thus suppressing vortex-induced vibration. Furthermore, by using the wave structure on the outer wall of the sheath body and utilizing its surface shape to suppress vortex-induced vibration, compared to the existing method of adding helical plates, this method not only suppresses vortex-induced vibration but also reduces the overall weight of the protective device, lowers fluid resistance, avoids greater gravitational loads and current drag on the cable, and improves the cable's installation stability. Attached Figure Description

[0015] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

[0016] Figure 1 This is a schematic diagram of a protective device applied to a suspended submarine cable according to Embodiment 1 of the present invention.

[0017] Figure 2 This is a schematic diagram of the sheath body according to Embodiment 1 of the present invention.

[0018] Figure 3 This is a cross-sectional view of the sheath assembly according to Embodiment 1 of the present invention.

[0019] Figure 4 This is a partial cross-sectional view of a protective device applied to a suspended submarine cable according to Embodiment 2 of the present invention.

[0020] Figure 5 This is a schematic diagram of a protective device applied to a suspended submarine cable according to Embodiment 3 of the present invention.

[0021] Figure 6 This is a schematic diagram of the sleeve according to Embodiment 3 of the present invention.

[0022] Figure 7 This is a cross-sectional view of the sheath assembly according to Embodiment 3 of the present invention.

[0023] In the picture: 1. Sheath assembly; 11. Sheath body; 111. Wave structure; 112. Arc-shaped groove; 113. Insertion part; 114. Insertion slot; 115. Arc-shaped part; 116. Extension part; 117. Limiting part; 12. Elastic pad; 13. First flexible pad; 14. Second flexible pad; 15. Sleeve; 151. Limiting groove; 152. Semi-cylindrical body; 153. Mounting hole; 2. Submarine cable. Detailed Implementation

[0024] To make the technical problems solved by the present invention, the technical solutions adopted, and the technical effects achieved clearer, the technical solutions of the present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0025] Example 1 like Figures 1 to 3 As shown, this invention provides a protective device for a suspended submarine cable (hereinafter referred to as the protective device), which is installed on the suspended section of the submarine cable 2 to reduce vortex-induced vibrations generated on the submarine cable 2. The protective device includes multiple sheath assemblies 1, which are distributed sequentially along the length of the submarine cable 2. The length of the submarine cable 2 is also the axial direction of the submarine cable 2. The sheath assemblies 1 are fitted around the periphery of the submarine cable 2 to allow seawater to flow over the surface of the sheath assemblies 1. The sheath assembly 1 includes two sheath bodies 11, which surround the periphery of the submarine cable 2. The two sheath bodies 11 are interlocked and detachably connected by fasteners. The fasteners can be existing bolts, screws, etc. By detachably connecting the two sheath bodies 11, it is convenient to install the two sheath bodies 11 on the submarine cable 2 or to remove the two sheath bodies 11 from the submarine cable 2. When the two sheath bodies 11 are installed on the submarine cable 2, the submarine cable 2 is clamped between the two sheath bodies 11, thus enclosing the submarine cable 2 within the space between them. The side of the sheath body 11 facing the submarine cable 2 is the inner wall, and the side of the sheath body 11 facing away from the submarine cable 2 is the outer wall. A continuous undulating wave structure 111 is provided on the outer wall of the sheath body 11, and the surface contour line of the wave structure 111 is wave-shaped. The wave line corresponding to the wave structure 111 extends along the length of the submarine cable 2, and the wave line corresponding to the wave structure 111 undulates radially along the submarine cable 2. This structure ensures that when seawater flows radially along the submarine cable 2, some seawater flows through the crest region of the wave structure 111, and some seawater flows through the trough region of the wave structure 111.

[0026] Understandably, by setting two detachably connected sheath bodies 11 to clamp the submarine cable 2, it is convenient to install the sheath body 11 onto the submarine cable 2. By setting a wave structure 111 on the outer wall of the sheath body 11, and extending the wave line corresponding to the wave structure 111 along the length of the submarine cable 2, the wave line corresponding to the wave structure 111 undulates radially along the submarine cable 2. When seawater impacts the submarine cable 2 radially, the seawater flows through the undulating outer wall of the sheath body 11, which can significantly change the flow field structure of the seawater flowing through the outer wall of the sheath body 11. The undulating outer wall of the sheath body 11 can force the seawater to generate a phase difference at different cross-sections, thereby destroying the correlation of the Karman vortex street in the axial direction of the submarine cable 2, preventing the vortices from falling off synchronously, and thus suppressing vortex-induced vibration. Furthermore, by setting a wave structure 111 on the outer wall of the sheath body 11, the surface shape of the sheath body 11 is used to suppress vortex-induced vibration. Compared with the method of adding spiral plates in the prior art, while suppressing vortex-induced vibration, it can also reduce the overall weight of the protection device, reduce fluid resistance, avoid the submarine cable 2 from bearing greater gravity load and ocean current drag force, and improve the installation stability of the submarine cable 2.

[0027] Specifically, the sheath body 11 has a plate-like structure, and its length is parallel to that of the submarine cable 2. Along its width, the sheath body 11 includes an arcuate portion 115 and two extensions 116. The two extensions 116 are respectively located at both ends of the arcuate portion 115. The arcuate portion 115 and the extensions 116 are an integral structure. The arcuate portion 115 is semi-circular to accommodate the outer wall shape of the submarine cable 2. An arcuate groove 112 for accommodating the submarine cable 2 is provided on one side of the arcuate portion 115 in the thickness direction, and the shape of the arcuate groove 112 matches the outer wall of the submarine cable 2. A wave structure 111 is located on the side of the arcuate portion 115 opposite to the arcuate groove 112, i.e., the wave structure 111 is located on the outer wall of the arcuate portion 115. The arc-shaped portion 115 is the main body of the sheath body 11. A wave structure 111 is provided on the outer wall of the arc-shaped portion 115 so that the wave structure 111 can cover most of the surface of the sheath body 11 to meet the requirements of suppressing vortex-induced vibration. The extension portion 116 provides space for the installation of fasteners. The free end of the extension portion 116 extends radially along the submarine cable 2. In the two sheath bodies 11, the extension portions 116 located on the same side of the submarine cable 2 are attached to each other, and the two attached extension portions 116 are connected and fixed by fasteners. Under the fixing action of the fasteners, the two sheath bodies 11 clamp the submarine cable 2, and the submarine cable 2 is accommodated in the space enclosed by the two arc-shaped grooves 112.

[0028] In some embodiments, if the thickness of the sheath body 11 is sufficient, the extension 116 can be omitted, and fasteners can be directly inserted into the side wall of the arc-shaped portion 115 to further reduce the fluid resistance of the entire sheath assembly 1.

[0029] To further enhance the effect of suppressing vortex-induced vibration, the extension 116 is configured as a wave plate structure. In some embodiments, the extension 116 can be integrally pressed into a wave shape, and the shapes of two extensions 116 installed together can be matched so that the two extensions 116 can fit tightly together. In some embodiments, the side of the extension 116 used for fitting can also be set as a plane, and the surface of the extension 116 through which seawater flows can be set as a wave shape. In some embodiments, both ends of the extension 116 in the length direction are set as flat structures to facilitate the installation of fasteners.

[0030] Specifically, the arc-shaped portion 115 can be integrally pressed into a wave shape. Two arc-shaped portions 115 are fastened together to form a corrugated tube-like structure. An arc-shaped clamp is provided on the inner wall of the arc-shaped portion 115, which is used to fit against the outer wall of the submarine cable 2. In other embodiments, a wave structure 111 can be provided only on the outer wall of the arc-shaped portion 115. Two arc-shaped portions 115 are fastened together to form a cylindrical structure. The inner wall of the arc-shaped portion 115 fits against the outer wall of the submarine cable 2, and the outer wall of the arc-shaped portion 115 is set as a wave structure 111 with varying heights. It should be noted that in this embodiment, the wave line corresponding to the wave structure 111 refers to the outer contour line of the cross-section of the arc-shaped portion 115 along the radial direction of the submarine cable 2.

[0031] Specifically, the sheath assembly 1 also includes an elastic pad 12. The elastic pad 12 is elastic, such as a rubber pad. In the sheath assembly 1, the elastic pad 12 is sandwiched between two extensions 116 located on the same side of the submarine cable 2. The function of the elastic pad 12 is to improve the connection sealing between the two sheath bodies 11. When the extension 116 is generally wavy, the shape of the elastic pad 12 is matched with the shape of the contact surface of the extension 116.

[0032] Specifically, the sheath assembly 1 further includes a first flexible pad 13 and a second flexible pad 14. Both the first flexible pad 13 and the second flexible pad 14 are elastic, such as rubber pads. The first flexible pad 13 is sandwiched between the arc-shaped portion 115 and the submarine cable 2 to improve the tightness of the installation between the entire sheath body 11 and the submarine cable 2, and to prevent the outer wall of the submarine cable 2 from being damaged by the arc-shaped portion 115. The surface of the wave structure 111 is covered with the second flexible pad 14, which protects the sheath assembly 1 from rigid contact with the external environment. In practical applications, the first flexible pad 13 and the second flexible pad 14 can be arranged reasonably and flexibly according to the actual situation. For example, only the first flexible pad 13, only the second flexible pad 14, or both the first flexible pad 13 and the second flexible pad 14 can be installed.

[0033] Example 2 like Figure 4As shown (some labels refer to the references) Figures 1 to 3 The protection device in this embodiment is similar to that in Embodiment 1, except that: along the length of the submarine cable 2, one end of the sheath body 11 is provided with a plug-in portion 113. The plug-in portions 113 on the two sheath bodies 11 are interlocked and combined to form a cylindrical structure. The end of the sheath body 11 opposite to the plug-in portion 113 is provided with a plug-in groove 114, and the plug-in grooves 114 on the two sheath bodies 11 form a space for accommodating the plug-in portion 113. In two adjacent sheath assemblies 1, the plug-in portion 113 in one sheath assembly 1 is inserted into the plug-in groove 114 in the other sheath assembly 1, so that the two adjacent sheath assemblies 1 can be plugged and fixed together, so as to connect multiple sheath assemblies 1 on the submarine cable 2 into a whole.

[0034] Example 3 like Figures 5 to 7 As shown (some labels refer to the references) Figures 1 to 3 The protective device in this embodiment is similar to that in Embodiment 1, except that the sheath assembly 1 further includes a sleeve 15. The sleeve 15 is fitted around the periphery of the submarine cable 2. The sleeve 15 includes two detachably connected semi-cylindrical bodies 152, which surround the periphery of the submarine cable 2 so that the submarine cable 2 is sandwiched between the two semi-cylindrical bodies 152. By setting the sleeve 15 to two semi-cylindrical bodies 152, it is easier to install the sleeve 15 onto the submarine cable 2. Two sheath bodies 11 surround the periphery of the sleeve 15, and the sheath bodies 11 are rotatable relative to the sleeve 15. It is understood that by setting the sleeve 15 to fit onto the submarine cable 2 and rotatably connecting the sheath bodies 11 to the sleeve 15, when the direction of the ocean current changes, due to the greater scouring resistance experienced by the extension 116, the sheath bodies 11 will rotate on their own under the action of the extension 116 to adapt to the actual direction of the ocean current. By rotating the sheath body 11 relative to the sleeve 15 to adapt to the actual direction of the ocean current, the extension 116 can rotate to the position of least resistance, thereby reducing the fluid resistance of the entire protective device. At the same time, the disturbance of the ocean current will cause the sheath body 11 to rotate. When the sheath body 11 rotates, it will disrupt the regularity of the eddy current, thereby enhancing the suppression effect on eddy-induced vibration.

[0035] Specifically, a mounting hole 153 is provided on the semi-cylindrical body 152 for fasteners to pass through, and the two semi-cylindrical bodies 152 are connected and fixed by fasteners. To avoid damaging the submarine cable 2, a first flexible protective pad 13 is sandwiched between the semi-cylindrical body 152 and the submarine cable 2. A limiting groove 151 is provided on the outer wall of the sleeve 15, and the limiting groove 151 is arranged in a ring around the periphery of the sleeve 15. A limiting part 117 is provided on the sheath body 11, and the shape of the limiting part 117 is configured to cooperate with the limiting groove 151. The limiting part 117 is located on the inner wall of the arc-shaped groove 112. The limiting part 117 is inserted into the limiting groove 151, and the limiting part 117 can slide along the length direction of the limiting groove 151. In this embodiment, the cross-section of the limiting groove 151 and the limiting part 117 are both rectangular. The limiting part 117 is slidably connected to the limiting groove 151. The length of the limiting part 117 is smaller than the length of the limiting groove 151 to reduce friction when the sheath body 11 rotates. By setting the limiting part 117 to be inserted into the limiting groove 151, while allowing relative rotation between the sheath body 11 and the sleeve 15, the sheath body 11 can also be limited to prevent it from moving along the length direction of the sleeve 15 (i.e., the length direction of the submarine cable 2), thus preventing the sheath body 11 from detaching from the sleeve 15. It should be noted that the limiting groove 151 is not a single integral annular groove. The limiting groove 151 is provided on the semi-cylindrical body 152, and the limiting grooves 151 on the two semi-cylindrical bodies 152 are interconnected to form a closed annular groove. Of course, in other embodiments, the limiting groove 151 can also be provided on the inner wall of the arc-shaped groove 112, and the limiting part 117 can be provided on the outer wall of the sleeve 15.

[0036] Specifically, the sleeve 15 is provided with multiple limiting grooves 151, which are spaced apart along the length of the sleeve 15. By providing multiple limiting grooves 151, the force between the sheath body 11 and the sleeve 15 is more even, preventing jamming when the sheath body 11 rotates. Along the length of the sleeve 15, one end of the sleeve 15 extends to the outside of the sheath body 11. The sleeve 15 located outside the sheath body 11 is provided with limiting grooves 151. It can also be understood that when the sheath assembly 1 is installed on the submarine cable 2, one limiting groove 151 is exposed to seawater. In two adjacent sheath assemblies 1, the limiting groove 151 located outside the sheath body 11 in one sheath assembly 1 is used to insert with the limiting part 117 on the sheath body 11 in the other sheath assembly 1. This structure can realize the installation and fixation between two adjacent sheath assemblies 1. In addition, the sheath body 11 in each sheath assembly 1 can rotate independently to adapt to the changing direction of ocean currents. For example, refer to Figure 6As shown, the sleeve 15 is provided with four limiting grooves 151. Correspondingly, in the same sheath assembly 1, the sheath body 11 is provided with four limiting parts 117. The three limiting grooves 151 on the left side of the sleeve 15 are inserted into the three limiting parts 117 on the right side of the sheath body 11. In this embodiment, the length of the sleeve 15 is the same as the length of the sheath body 11, one end of the sleeve 15 extends to the outside of the sheath body 11, and correspondingly, the other end of the sleeve 15 is spaced apart from the end face of the sheath body 11.

[0037] The beneficial effects of this embodiment are as follows: By setting two detachably connected sheath bodies 11 to clamp the submarine cable 2, it is convenient to install the sheath body 11 onto the submarine cable 2. By setting a wave structure 111 on the outer wall of the sheath body 11, and extending the wave line corresponding to the wave structure 111 along the length of the submarine cable 2, the wave line corresponding to the wave structure 111 undulates radially along the submarine cable 2. When seawater impacts the submarine cable 2 radially, the seawater flows through the undulating outer wall of the sheath body 11, which can significantly change the flow field structure of the seawater flowing through the outer wall of the sheath body 11. The undulating outer wall of the sheath body 11 can force the seawater to generate a phase difference at different cross-sections, thereby destroying the correlation of the Karman vortex street in the axial direction of the submarine cable 2, preventing the vortices from falling off synchronously, and thus suppressing vortex-induced vibration. Furthermore, by setting a wave structure 111 on the outer wall of the sheath body 11, the surface shape of the sheath body 11 is used to suppress vortex-induced vibration. Compared with the method of adding spiral plates in the prior art, while suppressing vortex-induced vibration, it can also reduce the overall weight of the protection device, reduce fluid resistance, avoid the submarine cable 2 from bearing greater gravity load and ocean current drag force, and improve the installation stability of the submarine cable 2.

[0038] The above description is only a preferred embodiment of the present invention. For those skilled in the art, there will be changes in the specific implementation and application scope based on the ideas of the present invention. The content of this specification should not be construed as a limitation of the present invention.

Claims

1. A protective device for suspended submarine cables, characterized in that, The cable includes multiple sheath assemblies, which are distributed sequentially along the length of the submarine cable. Each sheath assembly includes two detachably connected sheath bodies, and the submarine cable is clamped between the two sheath bodies. The outer wall of each sheath body is provided with a continuous undulating wave structure, and the wave line corresponding to the wave structure extends along the length of the submarine cable and undulates along the radial direction of the submarine cable.

2. The protective device for suspended submarine cables according to claim 1, characterized in that, Along the width direction of the sheath body, the sheath body includes an arc-shaped portion and extension portions disposed at both ends of the arc-shaped portion. The arc-shaped portion is provided with an arc-shaped groove for accommodating the submarine cable. The wave structure is disposed on the side of the arc-shaped portion away from the arc-shaped groove. The extension portions of the two sheath bodies located on the same side of the submarine cable are attached to each other and detachably connected by fasteners.

3. The protective device for suspended submarine cables according to claim 2, characterized in that, The extension is configured as a corrugated plate structure.

4. The protective device for suspended submarine cables according to claim 2, characterized in that, In the sheath assembly, an elastic pad is sandwiched between the two extensions located on the same side of the submarine cable.

5. The protective device for suspended submarine cables according to claim 2, characterized in that, A first flexible pad is sandwiched between the arc-shaped portion and the submarine cable; and / or, a second flexible pad is laid on the surface of the wave structure.

6. The protective device for suspended submarine cables according to claim 1, characterized in that, Along the length of the submarine cable, one end of the sheath body is provided with a plug-in part, and the other end is provided with a plug-in groove. In two adjacent sheath assemblies, the plug-in part is inserted into the plug-in groove.

7. The protective device for suspended submarine cables according to claim 1, characterized in that, The sheath assembly further includes a sleeve fitted around the periphery of the submarine cable. The sleeve includes two detachably connected semi-cylindrical bodies, with the submarine cable sandwiched between the two semi-cylindrical bodies. Two sheath bodies surround the periphery of the sleeve, and the sheath bodies are rotatable relative to the sleeve.

8. The protective device for suspended submarine cables according to claim 7, characterized in that, One of the sheath body and the sleeve is provided with a limiting groove, and the other is provided with a limiting part. The limiting part is inserted into the limiting groove and can slide along the length direction of the limiting groove.

9. The protective device for suspended submarine cables according to claim 8, characterized in that, The sleeve is provided with a plurality of limiting grooves, which are spaced apart along the length of the sleeve.

10. The protective device for suspended submarine cables according to claim 9, characterized in that, One end of the sleeve extends along its length to the outside of the sheath body. The sleeve located outside the sheath body is provided with the limiting groove. In two adjacent sheath assemblies, the limiting groove in one sheath assembly located outside the sheath body is used to insert with the limiting part on the sheath body in the other sheath assembly.

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