Double-self-locking anti-falling ocean pipe cable bending limiting device

Abstract

The invention discloses a double-self-locking anti-falling ocean pipe cable bending limiting device, and relates to the technical field of ocean pipe cable protection equipment. The bending limiter comprises a plurality of bending limiting units, each bending limiting unit is composed of two bending limiting single bodies, each bending limiting single body comprises a first connecting section and a second connecting section, each first connecting section is provided with a plurality of connectors, each second connecting section is provided with a plurality of grooves, and the connectors are matched with the grooves. The first connecting section can be arranged in the second connecting section and can move and rotate relative to the second connecting section. Each bending limiting unit is divided into a first bending limiting single body and a second bending limiting single body, and the first bending limiting single bodies and the second bending limiting single bodies are connected through mortise and tenon joint structures and bolts. The first connector is matched with the first groove, the second connector is matched with the second groove to form a double-bending-limiting protection structure, torque generated by bending of the ocean pipe cable can be borne at the same time, the problem of local stress concentration can be effectively solved, the connection strength is enhanced, and the stability of long-term service is effectively improved.

Description

Technical Field

[0001] The invention relates to the technical field of marine cable protection equipment, and in particular to a double self-locking anti-falling marine cable bending limiter. Background Art

[0002] As a bending protection device for flexible pipes and cables, bend limiters are mainly used to prevent excessive bending and breakage. They have the advantages of small space occupation and simple structure. At present, bend limiters generally adopt a Haff structure, which is connected end to end through the male and female heads. When the marine pipe and cable are subjected to large bending stress, they form a lock, thereby dispersing the stress to the surrounding structure to protect the pipe and cable. However, under the coupling effect of waves, ocean currents and scouring on the seabed, the protective effect of the bend limiter gradually weakens, making it difficult to effectively protect the marine pipe and cable in the long term, resulting in a high failure rate and huge economic losses.

[0003] Chinese patent document CN110762340A discloses an embedded steel cylinder type marine flexible cable bend limiter, including n sections of bend limiter body, each section of bend limiter body is connected by two identical monomers, each monomer is a variable diameter semi-cylindrical structure, including a male head, a neck section, a female head and an embedded steel cylinder with an angle; the embedded steel cylinder adopts a semi-cylindrical structure, in the middle neck section. The patent document adds a steel cylinder to the neck of the existing bend limiter to enhance the local rigidity and reduce the stress concentration at the excessive section of the bend limiter to improve the overall fatigue resistance. However, the production process of adding a steel cylinder to the neck is relatively complicated, and the long-term stability of the steel cylinder on the seabed cannot be guaranteed after long-term use. At the same time, in order to avoid the problem of loosening and separation of the bolts under the influence of seawater scouring and wave currents when connecting the two monomers, a large number of bolts are installed, which makes the installation and disassembly operations in the marine environment cumbersome, greatly reducing the construction efficiency. Summary of the invention

[0004] In view of the fact that the components added to the current bend limiter to improve durability have a complex structure, resulting in a complex production process, which cannot ensure long-term stability on the seabed, and the cumbersome installation and disassembly operations. At the same time, the problem of local stress concentration cannot be alleviated in the structure. The present invention provides a double self-locking and anti-detachment marine cable bending limiter.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions: a double self-locking anti-detachment marine cable bending limiter includes a plurality of bending limit units, each of which is axially arranged and connected, and has a channel for accommodating the marine cable, each of which is composed of two bending limit monomers, each of which is semi-cylindrical, including a first connecting section and a second connecting section, the outer wall of the first connecting section is axially arranged with a plurality of connectors protruding outward, and the inner wall of the second connecting section is axially arranged with a plurality of grooves formed by depressions, and the connectors are adapted to the grooves; between adjacent bending limit units, the first connecting section located on the rear side is arranged in the second connecting section located on the front side, and moves and rotates relative to the second connecting section; the bending limit unit is divided into a first bending limit monomer and a second bending limit monomer, and the first bending limit monomer and the second bending limit monomer are interlocked by a mortise and tenon structure, and are fixedly connected by bolts.

[0006] Furthermore, the outer wall of the first connecting section is stepped, including a primary step and a secondary step, the primary step is located outside the secondary step, and along the radial direction of the first connecting section, the primary step is lower than the secondary step.

[0007] Furthermore, the connector includes a first connector and a second connector, the first connector is located outside the primary step, the second connector is located outside the secondary step, and the second connector is higher than the first connector.

[0008] Furthermore, the inner wall of the second connecting section is stepped, including three steps and four steps, the three steps are located inside the four steps, and along the radial direction of the second connecting section, the three steps are lower than the four steps.

[0009] Furthermore, the groove includes a first groove and a second groove, the first groove is arranged on the three-step ladder, the second groove is arranged on the four-step ladder, the first connector is configured in the first groove, and the second connector is configured in the second groove.

[0010] Further, there is a gap between the first connecting head and the first groove, and there is also a gap between the second connecting head and the second groove.

[0011] Furthermore, a plurality of corresponding fixing holes are provided between the first bending limiting monomer and the second bending limiting monomer, the bolts are adapted to be inserted into the fixing holes, and are connected with gaskets and anti-loosening nuts.

[0012] Furthermore, both sides of the contact surface of the first bending limiting monomer have tenon structures, and both sides of the contact surface of the second bending limiting monomer have mortise structures, and the tenon structures are arranged inside the mortise structures.

[0013] Furthermore, the tenon structure is formed by a connecting block protruding from a contact surface of the first bending limiting unit, and the mortise structure is formed by a depression on a side wall of the second bending limiting unit.

[0014] Furthermore, each of the bending limiting units is made of polyurethane material.

[0015] The beneficial effects of the present invention are as follows: in the present invention, a double bending limit protection structure is formed by cooperating the first connector with the first groove and the second connector with the second groove, and the two connectors can be used to simultaneously bear the torque generated by the bending of the marine cable, thereby improving the bearing capacity, and can also effectively alleviate the problem of local stress concentration, and improve the strength of the connection between adjacent bending limit units. In the present invention, the separation between the first bending limit monomer and the second bending limit monomer is avoided by a fastening method combining the mortise and tenon structure with bolts, wherein the tenon structure of the first bending limit monomer is embedded in the mortise structure of the second bending limit monomer to improve the stability and convenience of the connection, and at the same time, the stability of the connection between the first bending limit monomer and the second bending limit monomer is further improved by bolts, gaskets and anti-loosening nuts. This fastening method not only significantly reduces the number of bolts used and reduces the difficulty of installation, but also improves the stability of the present invention under long-term service on the seabed. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 Shown is a schematic diagram of the structural principle of an embodiment of the present invention.

[0017] Figure 2 Shown Figure 1 sectional view of .

[0018] Figure 3 Shown Figure 2 Side view of .

[0019] Figure 4 Shown Figure 1 Schematic diagram of the structure of the second bending limiting monomer.

[0020] Explanation of the reference numerals in the accompanying drawings: 1. First bending limiting unit; 2. Second bending limiting unit; 3. Tenon structure; 4. Mortise structure; 5. First connecting section; 6. Second connecting section; 7. First connecting head; 8. Second connecting head; 9. First groove; 10. Second groove; 11. Fixing hole; 12. Bolt. DETAILED DESCRIPTION

[0021] The invention discloses a double self-locking anti-drop marine cable bending limiter. An implementation mode of the invention is described in detail below in conjunction with the accompanying drawings.

[0022] like Figure 1 As shown, the bending limiter includes a plurality of bending limit units, each of which is sequentially arranged and connected along the axial direction, and each of which has a channel for accommodating marine cables along the coaxial direction, and the aperture of the channel is larger than the diameter of the marine cables, so as to ensure that the marine cables can smoothly penetrate into the channel and have a certain degree of mobility. Each bending limit unit is made of polyurethane material, which has good elasticity and corrosion resistance, can adapt to complex seabed environments, and improves durability. Each bending limit unit is composed of a first bending limit monomer 1 and a second bending limit monomer 2, and the first bending limit monomer 1 and the second bending limit monomer 2 are approximately semi-cylindrical, and the first bending limit monomer 1 and the second bending limit monomer 2 are assembled to form a cylindrical bending limit unit. The first bending limit monomer 1 and the second bending limit monomer 2 both include a first connecting section 5 and a second connecting section 6, and the outer wall of the first connecting section 5 is stepped, including a first step and a second step, and the first step is located outside the second step, and along the radial direction of the first connecting section 5, the height of the first step is lower than the height of the second step. A plurality of connectors are arranged along the axial direction on the outer wall of the first connecting section 5. The connectors include a first connector 7 and a second connector 8. The first connector 7 is located at the outer edge of the primary step, and the second connector 8 is located between the primary step and the secondary step and at the outer edge of the secondary step. Along the radial direction of the first connecting section 5, the height of the first connector 7 is lower than that of the second connector 8.

[0023] Combination Figure 2 and Figure 3 As shown, the inner wall of the second connecting section 6 is stepped, including three steps and four steps, the three steps are located inside the four steps, and along the radial direction of the second connecting section 6, the three steps are lower than the four steps. The inner wall of the second connecting section 6 is arranged with a plurality of grooves along the axial direction, the grooves include a first groove 9 and a second groove 10, the first groove 9 is arranged on the third step, the second groove 10 is arranged on the four steps, and along the radial direction of the second connecting section 6, the top of the first groove 9 is lower than the top of the second groove 10. The first groove 9 is matched with the first connector 7, and there is a gap between the first connector 7 and the first groove 9. After the first connector 7 is arranged in the first groove 9, the first connector 7 can move and rotate relative to the first groove 9. The second groove 10 is matched with the second connector 8, and there is a gap between the second connector 8 and the second groove 10. After the second connector 8 is arranged in the second groove 10, the second connector 8 can move and rotate relative to the second groove 10.

[0024] The first bending limiting monomer 1 is connected to the second bending limiting monomer 2 through a mortise and tenon structure and a bolt 12, and the contact surface of the first bending limiting monomer 1 is in contact with the contact surface of the second bending limiting monomer 2. Both sides of the contact surface of the first bending limiting monomer 1 have a mortise structure 3, and the mortise structure 3 is formed by a connecting block protruding from the contact surface of the first bending limiting monomer 1. In this embodiment, the connecting block is in a rectangular shape. Both sides of the contact surface of the second bending limiting monomer 2 have a mortise structure 4, and the mortise structure 4 is formed by a recessed notch on the side wall of the second bending limiting monomer 2. The mortise structure 3 is arranged in the mortise structure 4 and is fixed by clamping with the mortise structure 4. The first bending limiting monomer 1 has a plurality of fixing holes 11, and the second bending limiting monomer 2 also has a plurality of fixing holes 11. The fixing holes 11 of the first bending limiting monomer 1 correspond to the fixing holes 11 of the second bending limiting monomer 2. The first bending limiting monomer 1 and the second bending limiting monomer 2 are connected by bolts 12 that are adapted to be inserted into the fixing holes 11, and the ends of the bolts 12 are fastened by gaskets and anti-loosening nuts.

[0025] When the front bend limiting unit and the rear bend limiting unit are installed on the marine cable, the front bend limiting unit includes a first bend limiting monomer 1 and a second bend limiting monomer 2. For ease of description, the rear bend limiting unit includes a third bend limiting monomer and a fourth bend limiting monomer, wherein the structure of the first bend limiting monomer 1 is the same as that of the third bend limiting monomer, and the structure of the second bend limiting monomer 2 is the same as that of the fourth bend limiting monomer. First, the channel on the first bend limiting monomer 1 in the front bend limiting unit is configured on the marine cable, and then the second bend limiting monomer 2 in the front bend limiting unit is fixedly engaged with the first bend limiting monomer 1 through the mortise and tenon structure, so that the tenon structure 3 on the first bend limiting monomer 1 can be adapted to be inserted into the mortise structure 4 of the second bend limiting monomer 2, and finally the first bend limiting monomer 1 and the second bend limiting monomer 2 are detachably fixedly connected by using bolts 12 in conjunction with gaskets and anti-loosening nuts. After the front bend limiting unit is installed, the channel on the third bend limiting unit in the rear bend limiting unit is arranged on the marine cable, and at the same time, the second connection section 6 on the third bend limiting unit can be sleeved on the first connection section 5 of the first bend limiting unit 1 or the second bend limiting unit 2, ensuring that the first connector 7 is arranged in the first groove 9 and the second connector 8 is arranged in the second groove 10. Then, the fourth bend limiting unit is embedded and fixed with the third bend limiting unit through the mortise and tenon structure, so that the tenon structure 3 on the third bend limiting unit can be inserted into the mortise structure 4 of the fourth bend limiting unit, and finally, the bolt 12 is matched with the gasket and the anti-loosening nut to detachably and fixedly connect the third bend limiting unit with the fourth bend limiting unit.

[0026] The first connector 7 cooperates with the first groove 9, and the second connector 8 cooperates with the second groove 10 to form a double bending limit protection structure. The double bending limit protection structure can use the first connector 7 and the second connector 8 to simultaneously bear the torque generated by the bending of the marine cable, thereby improving the bearing capacity, and can also alleviate the problem of local stress concentration, and improve the strength of the connection between the front bending limit unit and the rear bending limit unit. The first bending limit monomer 1 and the second bending limit monomer 2 are fastened by a combination of bolts 12 and mortise and tenon structures to avoid separation between the first bending limit monomer 1 and the second bending limit monomer 2. The tenon structure 3 of the first bending limit monomer 1 is embedded in the mortise structure 4 of the second bending limit monomer 2 to improve the stability of the connection. At the same time, the first bending limit monomer 1 and the second bending limit monomer 2 are further connected by bolts 12, gaskets and anti-loosening nuts. This fastening method not only significantly reduces the number of bolts 12 used, reduces the difficulty of installation, but also improves the stability under long-term service on the seabed.

[0027] Compared with the common submarine cable bending limiters on the market, the present invention has the following advantages: the maximum stress value is the lowest, and the cooperation between the first connector 7 and the second connector 8 can enable the present invention to have a higher safety margin and anti-destruction ability when subjected to stress; the stress distribution is more uniform. When the present invention is subjected to stress, the stress concentration point can be dispersed, reducing the high stress value borne by a single male and female head area, improving the bending bearing capacity, and avoiding structural fatigue or local damage caused by stress concentration; reducing the risk of local failure. The present invention can effectively improve the overall rigidity and bending resistance of the structure through the structural design of double male and female heads, and can maintain the stability of the structure even when the limit bending radius is reached. In extreme cases, when the first connector 7 is damaged, the second connector 8 can still play a bending limiting role on the marine cable and avoid the overall structure from falling off.

[0028] Of course, the above description is not a limitation of the present invention, and the present invention is not limited to the above examples. Changes, modifications, additions or substitutions made by technicians in this technical field within the essential scope of the present invention should also fall within the protection scope of the present invention.

Claims

1. A double self-locking anti-drop marine cable bending limiter, characterized in that: The invention comprises a plurality of bend limiting units, each of which is connected along the axial direction and has a channel for accommodating a marine cable. Each of the bend limiting units is composed of two bend limiting monomers. Each of the bend limiting monomers is semi-cylindrical and comprises a first connecting section (5) and a second connecting section (6). The outer wall of the first connecting section (5) is provided with a plurality of connectors protruding outwardly along the axial direction, and the inner wall of the second connecting section (6) is provided with a plurality of grooves recessed along the axial direction, and the connectors are matched with the grooves. Between adjacent bend limiting units, the first connecting section (5) located at the rear side is arranged in the second connecting section (6) located at the front side, and moves and rotates relative to the second connecting section (6). The bend limiting unit is divided into a first bend limiting monomer (1) and a second bend limiting monomer (2). The first bend limiting monomer (1) and the second bend limiting monomer (2) are interlocked by a mortise and tenon structure and fixedly connected by bolts (12).

2. A double self-locking anti-drop marine cable bending limiter according to claim 1, characterized in that: The outer wall of the first connecting section (5) is stepped, comprising a primary step and a secondary step, wherein the primary step is located outside the secondary step and along the radial direction of the first connecting section (5), the primary step is lower than the secondary step.

3. A double self-locking anti-drop marine cable bending limiter according to claim 2, characterized in that: The connector comprises a first connector (7) and a second connector (8), the first connector (7) being located outside the primary step, the second connector (8) being located outside the secondary step, and the second connector (8) being higher than the first connector (7).

4. A double self-locking anti-drop marine cable bending limiter according to claim 3, characterized in that: The inner wall of the second connecting section (6) is stepped, including three steps and four steps, wherein the three steps are located on the inner side of the four steps, and along the radial direction of the second connecting section (6), the three steps are lower than the four steps.

5. A double self-locking anti-drop marine cable bending limiter according to claim 4, characterized in that: The groove comprises a first groove (9) and a second groove (10); the first groove (9) is arranged on the three-step ladder, the second groove (10) is arranged on the four-step ladder, the first connector (7) is arranged in the first groove (9), and the second connector (8) is arranged in the second groove (10).

6. A double self-locking anti-drop marine cable bending limiter according to claim 5, characterized in that: There is a gap between the first connecting head (7) and the first groove (9), and there is also a gap between the second connecting head (8) and the second groove (10).

7. A double self-locking anti-drop marine cable bending limiter according to claim 1, characterized in that: A plurality of corresponding fixing holes (11) are provided between the first bending limiting monomer (1) and the second bending limiting monomer (2), and the bolts (12) are adapted to be inserted into the fixing holes (11) and are connected with gaskets and anti-loosening nuts.

8. The double self-locking anti-drop marine cable bending limiter according to claim 1 is characterized in that: Both sides of the contact surface of the first bending limiting monomer (1) are provided with tenon structures (3), and both sides of the contact surface of the second bending limiting monomer (2) are provided with mortise structures (4), and the tenon structures (3) are arranged in the mortise structures (4).

9. A double self-locking anti-drop marine cable bending limiter according to claim 8, characterized in that: The tenon structure (3) is formed by a connecting block protruding from the contact surface of the first bending limiting monomer (1), and the mortise structure (4) is formed by a depression in the side wall of the second bending limiting monomer (2).

10. A double self-locking anti-drop marine cable bending limiter according to claim 1, characterized in that: Each of the bending limiting units is made of polyurethane material.

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