Ocean engineering cable

Abstract

The ocean engineering mooring rope comprises a plurality of main stranded ropes and a core steel wire core, and the main stranded ropes are wound and woven outside the core steel wire core; the main stranded wire rope comprises a plurality of secondary stranded wire ropes and a plurality of secondary steel wire cores, and the secondary stranded wire ropes are wound and woven outside the secondary steel wire cores; the secondary stranded wire rope is obtained by winding a plurality of strands of stranded wires; the stranded wire comprises a steel wire rope bundle of an inner core and an outer wrapping layer wrapping the steel wire rope bundle. The outer coating layer is made of one of polypropylene, PET, polyamide, ultra-high molecular weight polyethylene or modified materials thereof, the rigidity is gradually reduced layer by layer from the core steel wire core to the main stranded wire rope formed by stranding the stranded wires coated with the high polymer materials, the characteristic that the outer part is soft and the inner part is rigid is realized, and the strength, the flexibility and the self-weight ratio are balanced; therefore, the ocean engineering cable has high strength, proper flexibility and flexibility, the dead weight ratio is reduced, and the service life is prolonged.

Description

Technical Field

[0001] The present application relates to a seabed pulling project, and in particular to a marine engineering cable. Background Art

[0002] As an important part of the marine engineering field, deep-sea tow cables play a key role in the development of seabed resources and the laying of communication optical cables. With the continuous increase in the depth of ocean exploration and the technical requirements, the requirements for tow cable performance are also increasing. The traditional tow cable design needs to meet the requirements of high strength and adaptability to complex underwater environments, while also taking into account a certain degree of flexibility and weight control to ensure construction efficiency and safety.

[0003] At present, in order to achieve the above goals, the industry usually adopts two main solutions: one is to use pure steel wire rope as the towing material, relying on its extremely high strength to ensure the reliability of the operation; the other is to choose chemical fiber ropes, using their lighter weight and better flexibility to reduce the difficulty of operation. In addition, there are some occasions where the corrosion resistance of ordinary materials is improved by coating a protective layer on the surface. However, these methods all have obvious limitations and have not fully achieved the comprehensive performance balance under ideal conditions.

[0004] Although the above measures can improve the problems caused by a single material to a certain extent, the existing technology still cannot effectively solve the problem of how to have both high strength and appropriate softness. Especially when facing deep sea water pressure and complex geological conditions, problems such as difficult deployment due to being too hard to control or poor stability due to being too soft and lacking sufficient support often occur. Therefore, there is an urgent need for an offshore engineering cable that can better coordinate the relationship between hardness, strength and deadweight. Summary of the invention

[0005] In order to better coordinate the relationship between the hardness, strength and deadweight of an ocean engineering cable, a marine engineering cable is provided.

[0006] The above first invention objective of the present invention is achieved through the following technical solutions: A marine engineering cable, comprising a main stranded wire rope and a core steel wire core, wherein the main stranded wire rope is in multiple numbers and is wound and braided outside the core steel wire core; The main twisted wire rope comprises a secondary twisted wire rope and a secondary steel wire core, wherein the secondary twisted wire rope is in multiple numbers and is wound and braided outside the secondary steel wire core; the secondary twisted wire rope is obtained by winding multiple strands of twisted wire; The stranded wire comprises a steel wire rope bundle of an inner core and an outer coating layer wrapping the steel wire rope bundle; The outer coating layer is one of polypropylene, PET, polyamide, ultra-high molecular weight polyethylene or modified materials thereof.

[0007] By adopting the above technical solution, the core steel wire core in the structure serves as the main load-bearing structure, providing high strength and high tensile resistance, ensuring the stability of the towline under high pressure and strong tension in the deep sea. The main stranded wire rope forms a secondary load-bearing layer to disperse the concentrated stress of the core steel wire; the secondary stranded wire rope is composed of steel wire strands wrapped with chemical fiber, which has both flexibility and local strength. The main / secondary stranded wire ropes are woven in layers to form a flexible mesh structure, which improves the torsion resistance and bending freedom. In the material composite design, steel wire is combined with polymer material, and the outer coating layer is made of polymer material to reduce the friction coefficient between the secondary strands during the complete process of the main stranded rope, reduce the surface wear during the towing process of the towing cable, and isolate seawater corrosion, extend the life of the steel wire, and absorb dynamic loads such as wave impact through elastic deformation; Use low-density polymer materials to replace some steel wires, greatly reducing the overall weight; From the core steel wire core to the main stranded rope made of stranded wires covered with polymer materials, the stiffness decreases layer by layer, achieving the characteristics of "soft outside and hard inside", balancing strength, flexibility and self-weight ratio. The marine engineering cable thus has high strength, appropriate softness and bendability, reduces the self-weight ratio and extends its service life.

[0008] Optionally: the steel wire rope bundle is obtained by winding multiple strands of steel wires.

[0009] By adopting the above technical solutions, the dynamic response is improved, and multiple strands are wound to form a "micro-damping unit". The vibration energy is consumed by friction between the strands, further improving the flexibility and fatigue resistance of marine engineering cables. The gaps between multiple steel wires can be filled with polymer materials to enhance the interfacial bonding between the steel wires and the outer coating and avoid interlayer delamination. A capillary barrier is formed between the multiple steel wires, which cooperates with the outer coating to block the seawater penetration path and reduce the corrosion rate.

[0010] Optionally: the winding structure of the steel wire rope bundle may be one of 8-strand spiral winding, 1 strand is 7-strand spiral winding of the core outer layer, 1 strand is 12-strand spiral winding of the core outer layer, 1 strand is 24-strand spiral winding of the core outer layer, and 1 strand is 37-strand spiral winding of the core outer layer.

[0011] By adopting the above technical solution and selecting the winding structure according to the needs, the stress dispersion uniformity of the marine engineering cable during twisting can be effectively improved.

[0012] Optional: The outer coating layer accounts for 20-40% of the stranded wire.

[0013] By adopting the above technical solution, the overall strength-to-weight ratio of the marine engineering cable is controlled so that both the strength and weight ratio can be taken into account to achieve a better value.

[0014] Optionally, the components of the outer coating layer include polypropylene, polyamide, and ultra-high molecular polyethylene, and the mass ratio of polypropylene, polyamide, and ultra-high molecular polyethylene is 100:125-138:100-120.

[0015] By adopting the above technical solution, the high molecular chain rigidity and hydrogen bonding of polyamide provide a high-strength skeleton, which significantly improves the overall strength as the largest component. The ultra-high molecular weight polyethylene has an ultra-long and highly oriented molecular chain, which forms an interpenetrating network with polyamide through physical entanglement, plays a synergistic reinforcement role and inhibits crack propagation. Polypropylene, as a flexible phase, fills the polyamide / ultra-high molecular weight polyethylene interface gap, reduces stress concentration, and makes the outer coating layer have excellent tensile strength. Ultra-high molecular weight polyethylene absorbs energy through molecular chain slippage during stretching, delaying the rupture of the outer coating layer. The high modulus of polyamide limits the excessive deformation of the outer coating layer, preventing the premature tensile failure of the ultra-high molecular weight polyethylene, forming a synergistic effect, and improving the overall tensile fracture rate of the outer coating layer. The viscoelastic buffer of polypropylene further disperses the local stress through elastic deformation, so that the outer coating layer has a high tensile fracture strength; Ultra-high molecular weight polyethylene has high crystallinity and non-polar molecular chains. Ultra-high molecular weight polyethylene + polypropylene and polyamide form a dense blend structure, which limits the water diffusion path, compensates for the water absorption problem of polyamide, and makes the composite material have low water absorption; Thus, performance optimization is achieved through a triple synergistic mechanism, so that the outer coating material has the advantages of high tensile strength, high tensile fracture rate and low water absorption, which is in line with the performance requirements of the outer coating for the marine engineering cable of this application.

[0016] Optionally, the outer coating layer also includes POE, and the mass ratio of POE to polypropylene is (13-16.5):100.

[0017] By adopting the above technical solution, POE can increase the sliding ability of the molecular chain after being blended with the matrix, thereby improving the elongation at break, and can significantly improve the ductility of the outer coating material. The addition of POE can also reduce the overall water absorption of the outer coating material, reduce the wear of the outer coating in the seabed environment, and reduce the failure of protection caused by seawater penetration, thereby improving the protective effect of the outer coating in addition to assisting the sliding between strands of the stranded wire and consuming vibration.

[0018] Optionally, the outer coating layer further comprises lanthanum oxide coated white carbon black, and the mass ratio of the lanthanum oxide coated white carbon black to polypropylene is (8.9-11.4):100.

[0019] By adopting the above technical solution, the lanthanum oxide-coated white carbon black has less agglomeration due to the electrostatic repulsion of rare earth ions, and can be more evenly dispersed in the outer coating layer material; The uniformly dispersed lanthanum oxide is coated with white carbon black, and the rare earth elements on its surface are chemically bonded to form a dense coating layer on the surface of the white carbon black. The coating layer containing the rare earth elements forms a chemical bond with the amino group of the polyamide, thereby improving the filler-matrix stress transfer efficiency and the tensile strength and tensile fracture rate of the outer coating layer material. In addition, the coating layer containing the rare earth elements will reduce the content of hydroxyl groups on the surface of the gas phase silica and reduce the water adsorption during the deposition process, thereby blocking the water penetration path in the outer coating layer and further reducing the water absorption of the outer coating layer. This improves the interclavicular sliding and protective effects of the outer cover layer.

[0020] Optionally, the outer coating layer further comprises polycarbodiimide, and the mass ratio of the polycarbodiimide to polypropylene is (4.3-5.8):100.

[0021] By adopting the above technical solution, polycarbodiimide can capture the carboxyl groups produced by hydrolysis, prevent the degradation chain reaction, delay the reduction of the mechanical properties of the outer coating layer when it is soaked in seawater, and extend the service life of the marine engineering cable.

[0022] In summary, this application has at least the following beneficial effects: From the core steel wire core to the main stranded wire rope made of stranded wires covered with polymer materials, the stiffness decreases layer by layer, achieving the characteristics of "soft outside and hard inside", balancing strength, flexibility and self-weight ratio. The marine engineering cable has high strength, appropriate softness and bendability, reduces the self-weight ratio and prolongs the service life; The outer coating layer is made of polypropylene, PET, polyamide or ultra-high molecular weight polyethylene or composite materials, which enhances stress dispersion and optimizes mechanical properties. It has excellent tensile strength, excellent tensile fracture rate and low water absorption, which matches the inter-strand sliding, vibration consumption and protection required by the marine engineering cable of this application. DETAILED DESCRIPTION

[0023] Raw material information Steel refers to the steel material used for the core steel wire core, secondary steel wire core, and wire rope bundle in this application. It can be adjusted and selected according to needs during actual production. This article accurately represents the improved performance changes of this application. The steel material used for the core steel wire core, secondary steel wire core, and wire rope bundle is uniformly high carbon steel SAE 1095.

[0024] Polypropylene is Borealis HD120MO, injection molding grade, melt index 20g / 10min.

[0025] PET, Zhejiang Wankai, WK-801, CAS No. 25038-59-9, intrinsic viscosity 0.80dL / g Polyamide is PA66, DuPont product 101L, density 1.14g / cm3, melting point 265℃, viscosity 2.5Pa·s.

[0026] Ultra-high molecular weight polyethylene, Beijing Oriental Petrochemical DF-704, molecular weight 3 million.

[0027] POE is Dow Chemical's product Engage TM 8180 (octene content 20%, melt index 0.5g / 10min), CAS No.: 26221-73-8.

[0028] Polycarbodiimide, a product of LANXESS, Germany P.

[0029] Lanthanum oxide coated white carbon black, the preparation method is as follows: Select white carbon black with a particle size of 0.5 μm and dry it at 80°C for 5 hours, add the dried white carbon black into deionized water, the mass ratio of white carbon black to deionized water is 1:11, ultrasonic treatment is performed for 30 minutes, and then add 0.23 mol / L lanthanum nitrate aqueous solution, the mass ratio of white carbon black to lanthanum nitrate is 3:1, add ammonia water dropwise under stirring to adjust the pH to 9, precipitate lanthanum hydroxide on the surface of white carbon black, keep the temperature for reaction for 4 hours, filter and wash until the washing liquid has a pH of 7, and obtain an intermediate product; The intermediate product was dried at 100° C. and 0.02 MPa vacuum for 10 h, and the particle size was sieved to 1 to 3 μm to obtain lanthanum oxide-coated white carbon black.

[0030] Preparation Example 1 The outer coating layer material comprises polypropylene, polyamide and ultra-high molecular polyethylene. The outer coating layer material is obtained by weighing polypropylene, polyamide and ultra-high molecular polyethylene in a mass ratio of 100:125:100 and then blending and extruding.

[0031] Preparation Example 2 An outer coating layer material, whose components are polypropylene, polyamide and ultra-high molecular polyethylene. The outer coating layer material is obtained by weighing polypropylene, polyamide and ultra-high molecular polyethylene in a mass ratio of 100:135:116 and then blending and extruding.

[0032] Preparation Example 3 The outer coating layer material comprises polypropylene, polyamide and ultra-high molecular polyethylene. The outer coating layer material is obtained by weighing polypropylene, polyamide and ultra-high molecular polyethylene in a mass ratio of 100:138:120 and then blending and extruding.

[0033] Preparation Example 4 The invention discloses an outer coating layer material, whose components are polypropylene, polyamide, ultra-high molecular polyethylene and POE. The outer coating layer material is obtained by weighing polypropylene, polyamide, ultra-high molecular polyethylene and POE in a mass ratio of 100:135:116:10 and then blending and extruding.

[0034] Preparation Example 5 An outer coating layer material, whose components are polypropylene, polyamide, ultra-high molecular polyethylene and POE. The outer coating layer material is obtained by weighing polypropylene, polyamide, ultra-high molecular polyethylene and POE in a mass ratio of 100:135:116:13 and then blending and extruding.

[0035] Preparation Example 6 An outer coating layer material, whose components are polypropylene, polyamide, ultra-high molecular polyethylene and POE. The outer coating layer material is obtained by weighing polypropylene, polyamide, ultra-high molecular polyethylene and POE in a mass ratio of 100:135:116:15 and then blending and extruding.

[0036] Preparation Example 7 An outer coating layer material, whose components are polypropylene, polyamide, ultra-high molecular polyethylene and POE. The outer coating layer material is obtained by weighing polypropylene, polyamide, ultra-high molecular polyethylene and POE in a mass ratio of 100:135:116:16.5 and then blending and extruding.

[0037] Preparation Example 8 The outer coating layer material comprises polypropylene, polyamide, ultra-high molecular polyethylene and POE. The outer coating layer material is obtained by weighing polypropylene, polyamide, ultra-high molecular polyethylene and POE in a mass ratio of 100:135:116:19 and then blending and extruding.

[0038] Preparation Example 9 An outer coating material, whose components are polypropylene, polyamide, ultra-high molecular polyethylene and POE. The outer coating material is obtained by weighing polypropylene, polyamide, ultra-high molecular polyethylene, POE and lanthanum oxide-coated white carbon black in a mass ratio of 100:135:116:15:7 and then blending and extruding.

[0039] Preparation Example 10 An outer coating material, whose components are polypropylene, polyamide, ultra-high molecular polyethylene and POE. The outer coating material is obtained by weighing polypropylene, polyamide, ultra-high molecular polyethylene, POE and lanthanum oxide-coated white carbon black in a mass ratio of 100:135:116:15:8.9 and then blending and extruding.

[0040] Preparation Example 11 An outer coating material, whose components are polypropylene, polyamide, ultra-high molecular polyethylene and POE. The outer coating material is obtained by weighing polypropylene, polyamide, ultra-high molecular polyethylene, POE and lanthanum oxide-coated white carbon black in a mass ratio of 100:135:116:15:10.8 and then blending and extruding.

[0041] Preparation Example 12 An outer coating material, whose components are polypropylene, polyamide, ultra-high molecular polyethylene and POE. The outer coating material is obtained by weighing polypropylene, polyamide, ultra-high molecular polyethylene, POE and lanthanum oxide-coated white carbon black in a mass ratio of 100:135:116:15:11.4 and then blending and extruding.

[0042] Preparation Example 13 An outer coating material, whose components are polypropylene, polyamide, ultra-high molecular polyethylene and POE. The outer coating material is obtained by weighing polypropylene, polyamide, ultra-high molecular polyethylene, POE and lanthanum oxide-coated white carbon black in a mass ratio of 100:135:116:15:13 and then blending and extruding.

[0043] Preparation Example 14 An outer coating material, whose components are polypropylene, polyamide, ultra-high molecular polyethylene and POE. The outer coating material is obtained by weighing polypropylene, polyamide and ultra-high molecular polyethylene, POE, lanthanum oxide-coated white carbon black and polycarbodiimide in a mass ratio of 100:135:116:15:7.5 and then blending and extruding.

[0044] Preparation Example 15 An outer coating material, whose components are polypropylene, polyamide, ultra-high molecular polyethylene and POE. The outer coating material is obtained by weighing polypropylene, polyamide and ultra-high molecular polyethylene, POE, lanthanum oxide-coated white carbon black and polycarbodiimide in a mass ratio of 100:135:116:15:8.9 and then blending and extruding.

[0045] Preparation Example 16 An outer coating material, whose components are polypropylene, polyamide, ultra-high molecular polyethylene and POE. The outer coating material is obtained by weighing polypropylene, polyamide and ultra-high molecular polyethylene, POE, lanthanum oxide-coated white carbon black and polycarbodiimide in a mass ratio of 100:135:116:15:10.8 and then blending and extruding.

[0046] Preparation Example 17 An outer coating material, whose components are polypropylene, polyamide, ultra-high molecular polyethylene and POE. The outer coating material is obtained by weighing polypropylene, polyamide and ultra-high molecular polyethylene, POE, lanthanum oxide-coated white carbon black and polycarbodiimide in a mass ratio of 100:135:116:15:11.4 and then blending and extruding.

[0047] Preparation Example 18 An outer coating material, whose components are polypropylene, polyamide, ultra-high molecular polyethylene and POE. The outer coating material is obtained by weighing polypropylene, polyamide and ultra-high molecular polyethylene, POE, lanthanum oxide-coated white carbon black and polycarbodiimide in a mass ratio of 100:135:116:15:13 and then blending and extruding.

[0048] The tensile strength, tensile elongation at break and water absorption of the outer coating materials of Preparation Examples 1 to 18 were tested, and the polypropylene, PET, polyamide and ultra-high molecular weight polyethylene in the raw materials were used as blank groups to prepare the same samples for testing.

[0049] The tensile strength and tensile breaking rate were tested according to ASTM D638, and the water absorption rate was tested according to ISO 62 (23° C. / 50% RH).

[0050] In addition, long-term water resistance (seawater) test was performed for Preparation Examples 14 to 18. Artificial seawater was prepared according to ASTM D1141, and the samples were immersed in 23±2°C for 30 days according to ASTM D543. The tensile strength was tested and the strength retention rate was calculated by comparison. The test results are shown in the following table.

[0051] Table 1. Test results of preparation examples 1 to 18 and blank group Combined with Table 1, by comparing Preparation Examples 1 to 3 and polyamide, it can be seen that the strength of Preparation Examples 1 to 3 is similar to that of polyamide, and the tensile fracture rate of Preparation Examples 1 to 3 is significantly greater than that of polyamide, and the water absorption rate of Preparation Examples 1 to 3 is significantly lower than that of polyamide. Therefore, in the outer coating material of the present application, the high molecular chain rigidity and hydrogen bonding of polyamide provide a high-strength skeleton, which significantly improves the overall strength as the largest component. The ultra-high molecular weight polyethylene has an ultra-long and highly oriented molecular chain, which forms an interpenetrating network with polyamide through physical entanglement and plays a synergistic reinforcement role, inhibiting crack propagation. Polypropylene fills the polyamide / ultra-high molecular weight polyethylene interface gap as a flexible phase, reduces stress concentration, and enables the outer coating layer to have excellent tensile strength; the ultra-high molecular weight polyethylene absorbs energy through molecular chain slip during stretching. The high modulus of polyamide limits excessive deformation of the outer coating layer, prevents premature tensile failure of ultra-high molecular weight polyethylene, forms a synergistic effect, and improves the overall tensile fracture rate of the outer coating layer. The viscoelastic buffer of polypropylene further disperses local stress with elastic deformation, so that the outer coating layer has high tensile fracture rate strength; ultra-high molecular polyethylene has high crystallinity and non-polar molecular chain. A dense blend structure is formed by ultra-high molecular polyethylene + polypropylene and polyamide, which limits the water diffusion path, compensates for the water absorption problem of polyamide, and makes the composite material have low water absorption; thereby, performance optimization is achieved through a triple synergistic mechanism, so that the outer coating material has the advantages of high tensile strength, high tensile fracture rate and low water absorption, which meets the performance requirements of the outer coating layer of the marine engineering cable in this application.

[0052] Further comparison of Preparation Examples 1 to 3 shows that the performance of Preparation Example 2 is better than that of Preparation Example 1 and Preparation Example 3. The present application further studies and improves the outer coating layer material, as shown in Preparation Examples 4 to 18 above.

[0053] Comparing Preparation Example 2 with Preparation Examples 4 to 8, Preparation Examples 4 to 8 further added POE on the basis of Preparation Example 2. In the test results, the tensile strength from low to high is Preparation Example 8, Preparation Example 2, Preparation Example 4, Preparation Example 7, Preparation Example 5, and Preparation Example 6, the tensile break rate from small to large is Preparation Example 2, Preparation Example 4, Preparation Example 8, Preparation Example 5, Preparation Example 7, and Preparation Example 6, and the water absorption rate from high to low is Preparation Example 2, Preparation Example 4, Preparation Example 5, Preparation Example 6, Preparation Example 8, and Preparation Example 7.

[0054] According to the results of Preparation Examples 2 and 4 to 7, the addition of POE to the outer coating layer of the present application can improve the tensile strength and elongation at break and reduce the overall water absorption of the outer coating layer material. This is because after POE is blended with the matrix, the sliding ability of the molecular chain can be increased, the ductility of the outer coating layer material can be improved, and POE has good hydrophobicity, which can reduce the wear of the outer coating layer in the seabed environment and the failure of protection caused by seawater penetration, thereby improving the protective effect of the outer coating layer in addition to assisting the sliding between strands of the stranded wire and consuming vibration.

[0055] At the same time, the strength of Preparation Example 8 increases with the addition of POE. However, the compatibility problem affects the internal interface and organic molecular chain distribution of the material, resulting in a decrease in performance. It can be seen that the addition of POE to the outer coating layer of this application should be within an appropriate range, such as the mass ratio of POE to polypropylene is (13-16.5):100.

[0056] Combining Preparation Example 6 with Preparation Examples 9 to 13, it can be seen that Preparation Examples 9 to 13 add lanthanum oxide-coated silica based on Preparation Example 6, and the amount of lanthanum oxide-coated silica added in Preparation Examples 9 to 13 increases successively.

[0057] In the test results, the tensile strengths are from low to high in the order of Preparation Example 6, Preparation Example 9, Preparation Example 13, Preparation Example 10, Preparation Example 11, and Preparation Example 12. The tensile strengths of the coating materials in Preparation Examples 6 and Preparation Examples 9 to 13 first increase and then decrease as the amount of lanthanum oxide-coated white carbon black added increases. The tensile fracture rates are as follows from small to large: Preparation Example 13, Preparation Example 6, Preparation Example 9, Preparation Example 10, Preparation Example 12, and Preparation Example 11. The tensile fracture rates of the coating materials in Preparation Examples 6 and Preparation Examples 9 to 13 first increase and then decrease as the amount of lanthanum oxide-coated white carbon black added increases. The water absorption rates from high to low are Preparation Example 6, Preparation Example 9, Preparation Example 10, Preparation Example 13, Preparation Example 11, and Preparation Example 12. The water absorption rates of the coating layer materials in Preparation Examples 6 and Preparation Examples 9 to 13 first decrease and then increase as the amount of lanthanum oxide-coated white carbon black added increases.

[0058] The reason is that the appropriate amount of lanthanum oxide coated white carbon black is added. Due to the electrostatic repulsion of rare earth ions, the lanthanum oxide coated white carbon black can be more evenly dispersed in the outer coating material, and then the coating containing rare earth elements forms a chemical bond with the amino group of polyamide, improving the filler-matrix stress transfer efficiency, and improving the tensile strength and tensile fracture rate of the outer coating material. In addition, the coating containing rare earth elements will reduce the gas phase silica during the deposition process to reduce the surface hydroxyl content and reduce water adsorption, thereby blocking the water penetration path in the outer coating, further reducing the water absorption of the outer coating. Excessive addition will lead to uneven dispersion and excessive inorganic / organic interface, increasing weak water permeation pathways, which will in turn lead to reduced performance.

[0059] Therefore, the mass ratio of lanthanum oxide-coated white carbon black to polypropylene in the outer coating layer material of the present application is (8.9-11.4):100.

[0060] Comparing Preparation Example 11 with Preparation Examples 14 to 18, Preparation Examples 14 to 18 added polycarbodiimide based on Preparation Example 11, and the amount of polycarbodiimide added in Preparation Examples 14 to 18 increased successively.

[0061] In the test results, the tensile strength of Preparation Example 11 and Preparation Examples 14 to 17 were similar, and Preparation Example 18 showed a significant decrease. The tensile break rate of Preparation Examples 11 and Preparation Examples 14 to 16 were similar, and Preparation Examples 17 to 18 gradually decreased. The water absorption rate of Preparation Examples 11 and Preparation Examples 14 to 17 decreased with the increase of the amount of polycarbodiimide added, and the water absorption rate of Preparation Example 18 increased. The reason is that polycarbodiimide can capture the carboxyl groups produced by hydrolysis, prevent the degradation chain reaction, delay the reduction of the mechanical properties of the outer coating layer when it is wetted by seawater, and extend the service life of the marine engineering cable. However, excessive addition of polycarbodiimide will lead to dispersion problems and affect the distribution of organic molecular chains, resulting in performance degradation.

[0062] Based on the fact that the water absorption rate dropped to a value close to the limit, the present application also conducted a long-term water resistance test on Preparation Examples 14 to 18. In the long-term water resistance test, the strength retention rate first increased and then decreased with the addition of polycarbodiimide.

[0063] Therefore, adding appropriate polycarbodiimide to the components of the outer coating layer in the present application can further delay the reduction of mechanical properties of the outer coating layer when it is wetted by seawater and extend the service life of the marine engineering cable. The mass ratio of polycarbodiimide to polypropylene is controlled to be (4.3-5.8):100.

[0064] Example 1 A marine engineering cable comprises a main stranded wire rope and a core steel wire core. The main stranded wire ropes are in multiple numbers and are wound and braided outside the core steel wire core.

[0065] The core wire core diameter is 1.8cm.

[0066] The main stranded wire rope comprises a secondary stranded wire rope and a secondary steel wire core.

[0067] The secondary steel wire core diameter is 0.5cm.

[0068] The secondary stranded wire ropes are multiple in number and are wound and braided outside the secondary steel wire core. The secondary stranded wire ropes are obtained by winding multiple strands of stranded wires.

[0069] The stranded wire comprises an inner core steel wire rope bundle and an outer sheath wrapping the steel wire rope bundle.

[0070] The steel wire rope bundle is obtained by winding multiple steel wires, and the diameter of each steel wire is 0.2 cm.

[0071] In this embodiment, 1 strand is 7 strands of spiral winding for the core outer layer. According to actual needs, it can also be 8 strands of spiral winding, 1 strand is 12 strands of spiral winding for the core outer layer, 1 strand is 24 strands of spiral winding for the core outer layer, or 1 strand is 37 strands of spiral winding for the core outer layer.

[0072] The 8-strand spiral winding has strong symmetry and outstanding torsion resistance, making it suitable for fast retraction and deployment operations, such as short-distance towing.

[0073] 1 strand is the core outer layer with 7 strands spirally wound, which has a balance between lightness and flexibility, low manufacturing cost, better fatigue resistance than single-strand structure, and is suitable for conventional operations at medium depth (1000-3000 meters).

[0074] 1 strand is the core with 12 outer strands spirally wound. The outer layer has a higher covering density, improved wear resistance, and stronger resistance to seawater penetration. It is suitable for high-friction seabed terrain and long-term cable laying tasks.

[0075] 1 strand is a core outer layer with 24 strands spirally wound, and multiple strands work together to disperse stress. The fluctuation of tensile strength under dynamic load is reduced, and the impact resistance is excellent. It is suitable for towing sonars on deep-sea research vessels and operations in extreme sea conditions.

[0076] 1 strand is a core outer layer with 37 strands spirally wound, with ultra-high flexibility, low bending stiffness, and extended metal fatigue resistance life, suitable for ultra-long distance optical fiber towing cables and precision instrument towing.

[0077] Through the stepped design selection of the number of outer strands, precise control of the tow cable performance can be achieved.

[0078] The outer coating layer is prepared from the material of Preparation Example 1, and the proportion of the outer coating layer in the stranded wire is 35wt%. In other embodiments, 20-40wt% can be selected to adjust the specific gravity of the marine engineering cable in turn, change the influence of gravity and buoyancy in seawater, and adapt to the requirements of the seabed terrain.

[0079] Embodiments 2 to 22 A marine engineering cable, which is different from Example 1 in that the material of the outer coating layer is different, as shown in the following table.

[0080] Table 2. Material information of the outer covering layer of the marine engineering cable of Examples 1 to 22 Comparative Example 1 A marine engineering cable, which is different from Example 1 in that the stranded wire is obtained by winding multiple strands of steel wires, with 1 strand as the core and 7 strands as the outer layer, and the diameter of each steel wire is 0.2 cm.

[0081] The hardness, strength and deadweight ratio of the marine engineering cables of Examples 1 to 22 and Comparative Example 1 were tested, and the test results are shown in the table below.

[0082] Table 3. Test results of Examples 1 to 23 and Comparative Example 1 Combining Examples 1 to 22 and Comparative Example 1, it can be seen that the tensile strength of Examples 1 to 22 is higher than that of Comparative Example 1 or is similar to that of Comparative Example 1, and the improved marine engineering cable of the present application does not show a significant decrease in tensile strength; the equal diameter specific gravity of Examples 1 to 22 is significantly lower than that of Comparative Example 1, so the improved marine engineering cable of the present application is significantly lighter in self-weight than the prior art, can obtain greater buoyancy in seawater, and is more labor-saving in pulling and winding operations; the bending strength of Examples 1 to 22 is significantly lower than that of Comparative Example 1, and the minimum bending radius of Examples 1 to 22 is significantly lower than that of Comparative Example 1, so the softness of the improved marine engineering cable of the present application is significantly lower than that of Comparative Example 1.

[0083] In summary, the improved marine engineering cable of the present application has moderate hardness, low specific gravity and high tensile strength, achieving synergistic optimization of hardness, strength and deadweight.

[0084] This specific embodiment is only an explanation of the present invention, and it is not a limitation of the present invention. After reading this specification, those skilled in the art can make non-creative modifications to this embodiment as needed, but as long as it is within the scope of protection required by the present invention, it will be protected by the patent law.

Claims

1. A marine engineering cable, characterized in that: It includes a main stranded wire rope and a core steel wire core, wherein the main stranded wire rope is in multiple numbers and is wound and braided outside the core steel wire core; The main stranded wire rope comprises a secondary stranded wire rope and a secondary steel wire core, wherein the secondary stranded wire rope is in multiple numbers and is wound and braided outside the secondary steel wire core; The secondary twisted wire rope is obtained by winding multiple strands of twisted wire; The stranded wire comprises a steel wire rope bundle of an inner core and an outer coating layer wrapping the steel wire rope bundle; The outer coating layer is one of polypropylene, PET, polyamide, ultra-high molecular weight polyethylene or modified materials thereof.

2. The marine engineering cable according to claim 1, characterized in that: The steel wire rope bundle is obtained by winding a plurality of steel wires.

3. The marine engineering cable according to claim 2, characterized in that: The winding structure of the steel wire rope bundle may be one of 8-strand spiral winding, 7-strand spiral winding with 1 strand as the core outer layer, 12-strand spiral winding with 1 strand as the core outer layer, 24-strand spiral winding with 1 strand as the core outer layer, and 37-strand spiral winding with 1 strand as the core outer layer.

4. The marine engineering cable according to claim 1, characterized in that: The outer coating of the stranded wire accounts for 20~40%.

5. The marine engineering cable according to claim 1, characterized in that: The components of the outer coating layer include polypropylene, polyamide and ultra-high molecular polyethylene, and the mass ratio of polypropylene, polyamide and ultra-high molecular polyethylene is 100:125~138:100~120.

6. The marine engineering cable according to claim 5, characterized in that: The outer coating layer also includes POE, and the mass ratio of POE to polypropylene is (13-16.5):

100.

7. The marine engineering cable according to claim 5, characterized in that: The outer coating layer also includes lanthanum oxide coated white carbon black, and the mass ratio of the lanthanum oxide coated white carbon black to polypropylene is (8.9-11.4):

100.

8. The marine engineering cable according to claim 5, characterized in that: The outer coating layer also includes polycarbodiimide, and the mass ratio of the polycarbodiimide to polypropylene is (4.3-5.8):100.

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