Superconducting material-based high-efficiency transmission cable for ship and preparation method of superconducting material-based high-efficiency transmission cable

Abstract

The invention relates to the field of cables, and discloses an efficient transmission cable for a ship based on a superconducting material and a preparation method thereof.The efficient transmission cable comprises an outer layer assembly and a cooling liquid flowing pipe located on the inner side of the outer layer assembly, and a flow channel for cooling liquid to flow is formed between the outer wall face of the cooling liquid flowing pipe and the outer layer assembly; a plurality of groups of conduction assemblies are arranged in the cooling liquid flowing pipe at equal intervals, a plurality of groups of wire cores are arranged on the inner sides of the conduction assemblies at equal intervals, and middle reinforcing cores are arranged among the plurality of groups of wire cores, so that a superconducting state with resistance approaching zero can be realized in a low-temperature environment, and Joule heat loss generated by resistance of a traditional cable is greatly reduced. Compared with a conventional cable, the total transmission loss can be reduced to below 50%, the electric energy utilization rate of a ship electric power system can be remarkably improved, and energy waste is reduced. The system is especially suitable for electric intensive ships such as large passenger ships and warships, can reduce the overall operation energy consumption, and accords with the energy-saving development trend of ships.

Description

Technical Field

[0001] The present invention relates to the field of cables, and in particular to a high-efficiency transmission cable for ships based on superconducting materials and a preparation method thereof. Background Art

[0002] In the field of shipbuilding and marine engineering, the performance of power transmission systems plays a decisive role in the operational efficiency, safety, and reliability of ships. Traditional marine cables have exposed many limitations when dealing with the challenges of increasing ship electrification and complex marine environments.

[0003] From an electrical performance perspective, the widespread use of various high-power devices on ships is driving increasing demands for cable current carrying capacity. The conductor materials and insulation structures of traditional cables limit further increases in current carrying capacity, making it difficult to meet the power demands of high-power devices operating simultaneously. This leads to increased power transmission losses and reduced energy utilization. For example, on large cruise ships, with numerous entertainment facilities, high-power lighting systems, and advanced propulsion systems operating simultaneously, the resistance losses of traditional cables increase significantly, resulting in significant energy waste and potentially causing safety hazards such as cable overheating.

[0004] In terms of adaptability to the marine environment, ships are constantly exposed to harsh conditions such as high humidity, salt spray corrosion, mechanical vibration, and extreme temperature fluctuations. The insulation and sheathing materials of traditional cables, such as ordinary rubber or polyvinyl chloride, are susceptible to aging and cracking in seawater corrosion and salt spray environments, leading to a decrease in insulation performance and even short circuit failures. Furthermore, during navigation, continuous mechanical vibration can loosen the internal conductor connections of the cable, affecting the stability of power transmission. For example, during the months-long transoceanic voyage of ocean-going cargo ships, traditional cables are subject to the harsh environment, significantly increasing the probability of failure, seriously impacting the normal operation of the ship.

[0005] In terms of space utilization and installation convenience, the compact interiors of ships and the complex wiring requirements place high demands on cable flexibility and ease of installation. Traditional cables lack flexibility, making routing difficult in confined spaces, increasing installation time and labor costs. Furthermore, excessive bending during installation can easily damage the cable's internal structure and reduce its service life. For example, in confined and equipment-intensive areas like ship engine rooms, traditional cable installation is extremely difficult and inefficient.

[0006] To address these issues, the application of superconducting technology in marine cables has become a research hotspot. Under specific low-temperature conditions, superconducting materials have near-zero electrical resistance, enabling near-lossless power transmission and significantly improving the efficiency of shipboard power systems. However, practical application of superconducting cables on ships requires overcoming a number of challenges. To this end, we propose a high-efficiency transmission cable for ships based on superconducting materials and its fabrication method. Summary of the Invention

[0007] In view of the deficiencies in the prior art, the present invention provides a high-efficiency transmission cable for ships based on superconducting materials and a preparation method thereof, which solves the above-mentioned problems.

[0008] To achieve the above-mentioned objectives, the present invention provides the following technical solutions: a high-efficiency transmission cable for ships based on superconducting materials and a preparation method thereof, comprising an outer layer component and a coolant flow tube located inside the outer layer component, a flow channel for the flow of cooling liquid is provided between the outer wall surface of the coolant flow tube and the outer layer component, a plurality of groups of conductive components are equidistantly arranged inside the coolant flow tube, a plurality of groups of wire cores are equidistantly arranged inside the conductive components, and an intermediate reinforcing core is provided between the plurality of groups of wire cores.

[0009] Preferably, the core is made of copper-based high-temperature superconducting material, and the copper-based high-temperature superconducting material includes any one of yttrium barium copper oxide, bismuth strontium calcium copper oxide, thallium barium calcium copper oxide or mercury barium calcium copper oxide.

[0010] Preferably, the outer layer component includes an outer rubber layer, an intermediate flame retardant layer and a thermal insulation layer, the intermediate flame retardant layer is compounded on the inner side of the outer rubber layer, the thermal insulation layer is compounded on the inner side of the intermediate flame retardant layer, the outer rubber layer is any one of chloroprene rubber, EPDM rubber or chlorinated polyethylene rubber, the intermediate flame retardant layer is any one of an intumescent flame retardant material, a composite of glass fiber cloth and a flame retardant rubber coating or a ceramic silicone rubber belt, and the thermal insulation layer is any one of aerogel felt, a multi-layer thermal insulation material or a rigid polyurethane foam.

[0011] Preferably, the flow channel includes annular grooves equidistantly opened on the surface of the coolant flow tube and multiple groups of strip-shaped connecting channels opened on the surface of the coolant flow tube, the multiple groups of strip-shaped connecting channels are respectively located between two adjacent annular grooves, and the strip-shaped connecting channels connect the two adjacent annular grooves, and circular holes are opened at both ends of the outer layer component, and the circular holes on both sides correspond to the positions of the annular grooves at the two ends of the coolant flow tube.

[0012] Preferably, the conducting component includes an annular connecting component, multiple groups of inner wall protrusions and an inner annular component, the inner side of the annular connecting component is fixedly installed with multiple groups of inner wall protrusions, the ends of the multiple groups of inner wall protrusions are fixedly installed with the inner annular component, the multiple groups of wire cores are arranged on the inner side of the inner annular component, and the position of the annular connecting component corresponds to the inside and outside of the annular groove position.

[0013] Preferably, the coolant flow pipe is provided with a plurality of connection holes at positions corresponding to the annular grooves, and the annular connection assembly is integrally formed with heat conduction protrusions at positions corresponding to the connection holes, and the heat conduction protrusions are located inside the connection holes.

[0014] Preferably, the inner sides of multiple groups of inner ring components are connected in series through multiple strip connecting blocks, and each strip connecting block is connected in series with multiple groups of inner ring components. An annular tube is fixedly installed at one end of the strip connecting block, and the wire core is arranged inside the annular tube, which wraps the wire core.

[0015] Preferably, an intermediate reinforcement core is provided between the multiple groups of annular tubes.

[0016] A method for preparing a high-efficiency transmission cable for ships based on superconducting materials, comprising the following steps: Step 1: Prefabrication of coolant flow pipe; Seamless pipe is used as base material and processed into straight pipe of required diameter through cold rolling or extrusion process; Use a CNC lathe to machine annular grooves at equal distances on the outer wall of the pipe; The adjacent annular grooves are connected by processing a strip-shaped connecting channel through laser cutting or milling; A connecting hole is drilled at the position corresponding to the annular groove, and the hole diameter matches the heat conduction protrusion of the annular connecting component; Electrolytic polishing of the inner and outer walls of the pipe; Step 2: Pretreatment of insulation layer: If it is aerogel felt or multi-layer insulation material, cut it into a coil that matches the length of the coolant flow pipe and the width is slightly larger than the circumference of the pipe; If it is rigid polyurethane foam, it is processed into a tubular shape by compression molding, with an inner diameter slightly larger than the outer diameter of the coolant flow pipe; Step 3: Composite molding: Flexible insulation layer: Fix the coolant flow pipe on the rotating fixture and evenly coat the outer wall with low-temperature curing silicone rubber adhesive; Start the rotary tooling and simultaneously spirally wrap the insulation layer coil around the outer wall of the pipe. Adhesive is used to bond the overlapped parts to ensure there are no wrinkles or bubbles. After winding is completed, it is cured at room temperature for one day to form a "thermal insulation layer-coolant flow pipe" complex; Hard insulation layer: Using the injection molding composite process, the pre-treated coolant flow pipe is placed into the mold as an insert; Inject molten polyurethane foam raw material into the mold to fill the gap between the pipe and the mold (i.e. the space outside the runner); Step 4: Compound the middle flame retardant layer and the outer rubber layer on the outside of the thermal insulation layer in sequence; Step 5: Assemble the inner ring component, strip connection block, ring tube and wire core according to the design, and fill the middle reinforcement core between the ring tubes to complete the preparation of the overall cable.

[0017] Compared with the prior art, the present invention provides a high-efficiency transmission cable for ships based on superconducting materials and a preparation method thereof, which has the following beneficial effects: Significantly improve power transmission efficiency and reduce energy consumption: The cable core utilizes copper-based high-temperature superconducting material, which achieves a near-zero resistance superconducting state at low temperatures, significantly reducing the Joule heating losses associated with traditional cables. Compared to conventional cables, this reduces total transmission losses to less than 50%, significantly improving the energy efficiency of ship power systems and reducing energy waste. This material is particularly suitable for power-intensive vessels such as large passenger ships and warships, reducing overall operating energy consumption and aligning with the trend toward energy-saving shipbuilding. Enhanced current carrying capacity and power density to meet high power requirements: Cable cores made of superconducting materials have extremely high current-carrying capacity, 3-5 times that of traditional cables of the same cross-section. This easily meets the power demands of the increasing number of high-power devices onboard ships, such as propulsion systems, radar equipment, and large-scale entertainment facilities. Without increasing the cable cross-section to increase current carrying capacity, higher power transmission can be achieved within limited space, adapting to the growing demand for ship electrification. Optimize structural design and improve space utilization: The overall structure utilizes a multi-layer composite design, with compact and rational component layout. The flow channel design between the outer components and the coolant flow tubes ensures efficient cooling without occupying excessive space. The series structure of the conductive components and the placement of a central reinforcing core simplify the internal layout while ensuring strength. Compared to traditional cables, while maintaining the same power transmission requirements, the overall size is smaller and the flexibility is improved, making it easier to route and install within the confines of a vessel, reducing the internal space occupied and increasing the flexibility of the overall ship layout. Enhance environmental adaptability and extend service life: The outer rubber layer is made of seawater-, ozone-, and chemical-resistant materials, effectively protecting against salt spray, moisture, and other corrosive agents in the marine environment. The flame-retardant middle layer provides fire-resistant and heat-insulating properties to mitigate the risk of high temperatures or fires on board. The thermal insulation layer reduces the impact of external heat on the internal low-temperature environment, ensuring cooling system efficiency. Furthermore, the composite process of each component ensures structural stability, capable of withstanding mechanical vibration and shock during navigation, significantly reducing the probability of failure due to environmental factors and extending the cable's service life. Improve operational stability and safety: The zero-resistance nature of superconducting materials reduces heat generation and the risk of fires caused by overheating. The cooling system, through the circulation of refrigerant fluids such as liquid nitrogen, continuously provides a stable low-temperature environment for the superconducting material, ensuring its stable superconducting properties and preventing unstable power transmission caused by temperature fluctuations. The intermediate flame-retardant layer can slow the spread of flames in the event of a fire, buying time for emergency response on board. The intermediate reinforcement core enhances the overall strength and toughness of the cable, reducing the possibility of short circuits and disconnections due to mechanical damage, further improving the safety and reliability of the ship's power system. Reduce long-term operating costs: Although the initial R&D and manufacturing costs of superconducting cables are relatively high, from a long-term operation perspective, their low-loss characteristics can significantly reduce electricity waste and lower the energy consumption costs of ships; their longer service life reduces the number of replacements and maintenance times, reducing operation and maintenance costs; at the same time, their efficient power transmission capabilities can optimize the configuration of the ship's power system, reduce unnecessary equipment redundancy, and indirectly reduce the overall operation and management costs of the ship. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the structure of the present invention; Figure 2 for Figure 1 A in the figure is a partially enlarged schematic diagram; Figure 3 Schematic diagram of the coolant flow pipe; Figure 4 is a schematic side view of a coolant flow pipe; Figure 5 for Figure 4 AA cross-sectional view in FIG; Figure 6 for Figure 5 A partial enlarged schematic diagram of point B in FIG.

[0019] In the figure: 1. Outer rubber layer; 2. Middle flame-retardant layer; 3. Heat-insulating layer; 4. Circular hole; 5. Coolant flow pipe; 6. Annular groove; 7. Strip-shaped connecting channel; 8. Connecting hole; 9. Heat-conducting protrusion; 10. Annular connecting component; 11. Inner wall protrusion; 12. Inner annular component; 13. Strip-shaped connecting block; 14. Annular tube; 15. Wire core; 16. Middle reinforcing core. DETAILED DESCRIPTION

[0020] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0021] See also Figure 1-6 A high-efficiency transmission cable for ships based on superconducting materials includes an outer layer component and 5 located inside the outer layer component, a flow channel for cooling liquid is provided between the outer wall surface of the 5 and the outer layer component, a plurality of groups of conductive components are arranged equidistantly inside the 5, a plurality of groups 15 are arranged equidistantly inside the conductive components, and 16 is provided between the plurality of groups 15.

[0022] 15. Copper-based high-temperature superconducting materials are used, and the copper-based high-temperature superconducting materials include any one of yttrium barium copper oxide, bismuth strontium calcium copper oxide, thallium barium calcium copper oxide or mercury barium calcium copper oxide. The copper-based high-temperature superconducting material is produced by the powder-in-tube method, and the copper-based high-temperature superconducting material is ground into powder to obtain superconducting powder. The superconducting powder is then filled into a metal tube and made into a strip through drawing, rolling and heat treatment.

[0023] The outer layer components include 1, 2 and 3, wherein 2 is compounded on the inner side of 1, and 3 is compounded on the inner side of 2. 1 is any one of chloroprene rubber, EPDM rubber or chlorinated polyethylene rubber. 2 is any one of an intumescent flame retardant material, a composite formed by glass fiber cloth and a flame retardant adhesive coating, or a ceramic silicone rubber belt. 3 is any one of aerogel felt, a multi-layer insulation material or a rigid polyurethane foam.

[0024] The flow channel includes 6 opened at equal intervals on the surface of 5 and multiple groups of 7 opened on the surface of 5, the multiple groups of 7 are respectively located between two adjacent 6, and 7 connects the two adjacent 6, 4 is opened at both ends of the outer layer component, and the 4 on both sides respectively correspond to the positions of 6 at the two ends of 5. The two 4 are connected to the pipeline, and then liquid nitrogen or other refrigeration liquid is injected, which can realize circulation on the outer wall surface of 5, and at the same time transfer the temperature to the conduction component, and then transfer it to 15 to realize superconductivity.

[0025] The conductive components include 10, multiple groups 11 and 12. Multiple groups 11 are fixedly installed on the inner side of 10, 12 is fixedly installed at the ends of multiple groups 11, and multiple groups 15 are arranged on the inner side of 12. The position of 10 corresponds to the inside and outside of 6.

[0026] There are multiple groups of 8 at the positions corresponding to 6 of 5, and 9 is integrally formed at the positions corresponding to 8 of 10. 9 is located inside 8. When liquid nitrogen flows, it passes through 6 and contacts 9, and then transfers the temperature to 10, 11 and 12.

[0027] The inner sides of the multiple groups 12 are connected in series through multiple 13, and each 13 is connected in series with multiple groups 12. One end of the 13 is fixedly mounted with 14, and the 15 is arranged inside the 14, and the 14 wraps the 15 to achieve low-temperature superconductivity.

[0028] 16 is provided between the multiple groups of 14. By adding 16, the strength and toughness of the cable can be further increased.

[0029] Structure Description: External rubber layer 1: As the outermost layer of the cable, it comes into direct contact with the external environment and protects the internal structure. It is made of chloroprene rubber, EPDM rubber, or chlorinated polyethylene rubber. These materials offer excellent wear, weather, and corrosion resistance, resisting erosion from seawater, humid air, mechanical friction, and other external factors, ensuring the cable's stability and service life in the complex ship environment. Intermediate flame-retardant layer 2: Laminated inside the outer rubber layer 1, it primarily provides fire-blocking and heat-insulating functions, slowing the spread of flames and reducing heat transfer to the interior. It is made of either an intumescent flame-retardant material, a composite of fiberglass cloth and a flame-retardant adhesive coating, or a ceramic silicone rubber tape. Intumescent flame-retardant materials expand upon exposure to fire, forming a dense charcoal layer that isolates oxygen and heat. Fiberglass cloth is heat-resistant and non-flammable, and a flame-retardant adhesive coating enhances its flame-retardant properties and adheres seamlessly to the inner and outer layers. The ceramic silicone rubber tape, while flexible at room temperature, rapidly ceramicizes upon exposure to fire to form a hard, inorganic shell. It offers excellent flame-blocking and heat-insulating properties, is environmentally friendly and halogen-free, and meets ship fire safety requirements. Thermal Insulation Layer 3: Laminated inside the intermediate flame-retardant layer 2, its core function is to reduce the transfer of external heat into the low-temperature areas within the cable, thereby reducing the energy consumption of the refrigeration system and providing a suitable low-temperature environment for the superconducting material. It is made of either aerogel felt, multi-layer insulation material, or rigid polyurethane foam. Aerogel felt has extremely low thermal conductivity, excellent thermal insulation properties, and is lightweight and cryogenically resistant. Multi-layer insulation material is composed of alternating layers of aluminum foil or aluminized film and fiberglass cloth, achieving efficient insulation through a combination of reflective and low-thermal conductivity materials. Rigid polyurethane foam has a closed-cell structure, low thermal conductivity, and high mechanical strength. Choosing a cryogenically resistant material prevents embrittlement in ultra-low-temperature environments. Circular holes 4: These holes, located at either end of the outer component, correspond to the annular grooves 6 at the extreme ends of the coolant flow tube 5. By connecting pipes to these two holes, liquid nitrogen or other refrigerant liquids can be injected into the flow channel, providing inlet and outlet channels for the coolant's circulation. These holes are crucial for achieving cooling system circulation. Coolant flow tube 5: Located inside the outer layer, it serves as the primary channel for coolant flow. Multiple conductive components are equidistantly spaced within it. Made of ultra-low-temperature-resistant, high-strength materials such as 316L stainless steel or aluminum alloy, it maintains excellent toughness and strength in cryogenic environments like liquid nitrogen. Its smooth surface reduces flow resistance. The space between its outer wall and the outer layer forms a channel for the cooling liquid. Its structural design and material properties ensure stable circulation of the cooling liquid, delivering low temperatures to the conductive components and wire core 15. Annular grooves 6 are evenly spaced on the surface of the coolant flow tube 5 and form a crucial component of the flow path. Once injected, the coolant flows within these grooves. Their annular structure increases the contact area with the outer wall of the coolant flow tube 5, improving cooling efficiency and facilitating even transfer of low temperatures to the coolant flow tube 5, which in turn transmits the low temperature to the wire core 15 via the conductive assembly. Strip-shaped connecting channels 7: Multiple groups are opened on the surface of the coolant flow tube 5, and are located between two adjacent annular grooves 6, while also connecting two adjacent annular grooves 6. Their function is to connect the independent annular grooves 6 with each other, forming a complete circulation channel, ensuring that the cooling liquid can circulate smoothly throughout the channel, avoiding cooling dead spots, and ensuring uniform cooling effect. Connection hole 8: Located on the coolant flow tube 5 at the location corresponding to the annular groove 6, it provides a mounting and connection channel for the heat transfer protrusion 9. Through connection hole 8, the heat transfer protrusion 9 can contact the coolant flow tube 5, thereby transferring the low temperature of the cooling liquid in the annular groove 6 to the conductive component. This is a key connection structure for achieving low-temperature conduction. Heat transfer protrusion 9: This protrusion is integrally formed on the annular connector 10 at the location corresponding to the connection hole 8 and is located inside the connection hole 8. When a cooling liquid such as liquid nitrogen flows within the annular groove 6, it comes into contact with the heat transfer protrusion 9, efficiently transferring the low temperature to the annular connector 10. The heat transfer protrusion 9 then transfers the low temperature to the inner annular component 12 via the inner wall protrusion 11, ultimately transferring the low temperature to the wire core 15. This is a critical structure in the low-temperature transfer path. Annular connecting assembly 10: As part of the conductive assembly, its position corresponds to the inside and outside of annular groove 6. Multiple sets of inner wall protrusions 11 are fixedly mounted on the inner side. These protrusions receive low temperatures from the cooling liquid through heat-conducting protrusions 9 and transfer them to the inner wall protrusions 11, thus fulfilling the dual functions of connecting and transferring low temperatures, ensuring that the low temperatures are efficiently transferred from the flow channel to the inner annular assembly 12. Inner wall protrusion 11 is fixedly mounted on the inner side of annular connecting assembly 10, with its distal end fixedly connected to inner annular assembly 12. Its primary function is to transfer the low-temperature received by annular connecting assembly 10 to inner annular assembly 12. Its structural design also enhances the overall stability and strength of the conductive assembly, ensuring a smooth low-temperature transfer path and the structural reliability of the assembly. Inner annular assembly 12: Connected to annular connector assembly 10 via inner wall protrusions 11, multiple cores 15 are located inside it. This assembly receives low-temperature heat from inner wall protrusions 11 and transfers it to the cores 15, providing the low-temperature environment necessary to maintain the superconducting state. Its annular structure also provides a certain degree of stability and protection for the cores 15. Strip-shaped connecting blocks 13 are used to connect multiple sets of inner ring assemblies 12 in series. Each strip-shaped connecting block 13 connects multiple sets of inner ring assemblies 12 in series. This series connection forms a single integrated structure, enhancing the integrity and stability of the conductive assembly. It also facilitates the transfer of low temperatures between the individual inner ring assemblies 12, ensuring a consistent low-temperature environment. Ring tube 14: Fixedly mounted at one end of the strip-shaped connecting block 13, it houses the core 15, encasing and protecting it. This encapsulation reduces heat exchange between the core and the outside world, maintaining a low temperature and ensuring its superconducting state. It also provides mechanical protection from damage from external structures. Core 15: Made of copper-based high-temperature superconducting material, including yttrium barium copper oxide, bismuth strontium calcium copper oxide, thallium barium calcium copper oxide, or mercury barium calcium copper oxide. Produced using the powder-in-tube method, the copper-based high-temperature superconducting material is first ground into a powder to produce superconducting powder. This powder is then filled into a metal tube and drawn, rolled, and heat-treated to form a strip. Core 15 is the core component of the cable's efficient power transmission. It exhibits superconducting properties at low temperatures, achieving zero resistance and enabling low-loss or even lossless power transmission. Intermediate reinforcement core 16: Located between the multiple annular tubes 14, it primarily enhances the cable's strength and toughness. Its structural support improves the cable's overall mechanical performance, enabling it to withstand certain external forces such as stretching and bending during shipboard installation and use. This reduces damage to the cable caused by mechanical stress and ensures its structural stability and service life.

[0030] A method for preparing a high-efficiency transmission cable for ships based on superconducting materials, comprising the following steps: Production of outer components: Insulation layer 3 pretreatment: The insulation layer roll is unrolled through the unwinder. If it is a flexible material (such as aerogel felt, MLI), it can directly enter the composite station; if it is a hard material (such as PU foam), it needs to be pre-processed into a tube or semi-tube shape.

[0031] Middle flame retardant layer 2 composite: If the flame retardant layer is in the form of a strip (such as expanded graphite strip or ceramic silicone rubber strip), it should be spirally wound around the outside of the thermal insulation layer 3 using a winding machine. The winding tension should be uniform (to avoid wrinkles), and the overlap rate should be controlled at 10%-20% to ensure sealing.

[0032] If the flame retardant layer is a coating (such as flame retardant glue), an extrusion coating process is used to evenly coat the molten flame retardant glue on the outside of the thermal insulation layer, and the coating is solidified by cooling to form a continuous coating.

[0033] External rubber layer 1 compound: The extrusion coating process is used: the rubber raw material (such as CR, EPDM) is heated and melted in an extruder, and then continuously coated on the outside of the flame retardant layer 2 in a tubular form through a mold. The extrusion temperature is adjusted according to the rubber type (such as about 120-150℃ for EPDM) to ensure that the rubber and the flame retardant layer are tightly fitted.

[0034] Vulcanization and curing: The composite outer layer component enters the vulcanization tank or continuous vulcanization production line (such as steam vulcanization, microwave vulcanization) to cross-link and cure the rubber layer to enhance its mechanical strength and aging resistance; at the same time, the adhesive of the flame retardant layer (if any) is also cured at this stage to ensure a strong bond between the layers.

[0035] Post-processing stage: Cooling: After vulcanization, the components are cooled to room temperature through a cold water tank to avoid degradation of the performance of the inner layer materials (such as the insulation layer) due to high temperature.

[0036] Cutting and Inspection: Cut according to cable length requirements, conduct ultrasonic testing or visual inspection to check the fit between layers to ensure there are no bubbles, delamination or damage.

[0037] Prefabrication of coolant flow pipe 5: Step 1: Tube Forming: Seamless pipes (316L stainless steel or aluminum alloy) are used as the base material and are processed into straight pipes of the required diameter through cold rolling or extrusion (the diameter is determined by the flow channel design and must match the inner diameter of the insulation layer of the outer component).

[0038] Step 2: Structural processing (annular groove 6, strip-shaped connecting channel 7, connecting hole 8): Use a CNC lathe to machine annular grooves 6 at equal intervals on the outer wall of the pipe. The depth and width of the grooves are designed according to the flow rate of the flow channel (usually 5-10mm in depth and 10-20mm in width); The strip-shaped connecting channels 7 are processed by laser cutting or milling to connect the adjacent annular grooves 6 to ensure that the liquid nitrogen can circulate; At the position corresponding to the annular groove 6, a connecting hole 8 is processed by a drilling machine, and the hole diameter matches the heat conduction protrusion 9 of the annular connecting component 10 (the gap is controlled at 0.1-0.3mm to ensure heat conduction efficiency).

[0039] Step 3: Surface Preparation: Electrolytically polish the inner and outer walls of the pipe to reduce surface roughness (Ra ≤ 0.8 μm) and reduce liquid nitrogen flow resistance; spray a low-temperature compatible adhesive primer (such as silicone adhesive) on the outer wall to enhance the bonding strength with the thermal insulation layer 3.

[0040] Composite process of outer layer component and coolant flow pipe 5: It is necessary to achieve a tight bond between the "insulation layer 3 → coolant flow tube 5" and reserve space for the flow channel (the gap between the insulation layer and the coolant flow tube is the outer boundary of the liquid nitrogen flow channel). The process is as follows: Step 1: Pretreatment of thermal insulation layer 3: If using aerogel blanket or multi-layer insulation (MLI), cut it into a coil that matches the length of the coolant flow pipe 5 and is slightly wider than the pipe circumference (allowing a 10-20mm overlap). If it is a rigid polyurethane foam, it is processed into a tubular shape by compression molding, and the inner diameter is slightly larger than the outer diameter of the coolant flow pipe 5 (a flow channel gap is reserved, usually 0.5-1 mm).

[0041] Step 2: Composite Molding: Flexible insulation layer (aerogel felt / MLI): Fix the coolant flow pipe 5 on the rotating fixture, and evenly coat the outer wall with low-temperature curing silicone rubber adhesive (such as Dow Corning 734); Start the rotary tooling (speed 5-10r / min), and simultaneously spirally wrap the insulation layer coil around the outer wall of the pipe. Adhesive is used to bond the overlapped parts to ensure there are no wrinkles or bubbles. After winding is completed, it is cured at room temperature for 24 hours (or accelerated curing in a 60°C oven for 4 hours) to form a "thermal insulation layer-coolant flow pipe" complex.

[0042] Rigid insulation layer (polyurethane foam): Using the injection molding composite process, the pre-treated coolant flow pipe 5 is placed into the mold as an insert; Inject molten polyurethane foam raw material (temperature 80-100°C) into the mold to fill the gap between the pipe and the mold (i.e. the space outside the runner); Step 3: Compounding of the outer rubber layer 1 and the middle flame retardant layer 2: According to the previously designed "continuous lamination process", the middle flame retardant layer 2 and the outer rubber layer 1 are compounded in sequence on the outside of the thermal insulation layer 3, and attention is paid to controlling the composite tension (to avoid squeezing the thermal insulation layer and causing the flow channel gap to become smaller).

[0043] After cooling and solidification, the mold is removed and the polyurethane foam and the outer wall of the pipe are formed into a whole through physical biting and chemical bonding.

[0044] Assembly of the conduction component and the coolant flow pipe 5: After the outer layer assembly and the coolant flow pipe 5 are assembled, the heat conduction protrusion 9 of the annular connection assembly 10 is inserted into the connection hole 8 of the coolant flow pipe and fixed by interference fit or low-temperature welding such as silver-copper brazing to ensure a smooth heat conduction path; Subsequently, the inner annular component 12, the strip connecting block 13, the annular tube 14 and the wire core 15 are assembled according to the design, and the intermediate reinforcing core 16 is filled between the annular tubes 14 to complete the preparation of the entire cable.

[0045] 3. Key process points: Runner gap control: The runner gap between the insulation layer 3 and the coolant flow pipe 5 must be uniform (error ≤ 0.2mm) to avoid local narrowing that causes poor liquid nitrogen flow. It can be monitored in real time through mold positioning or laser diameter measuring instrument.

[0046] Low-temperature compatibility: All adhesives must be resistant to ultra-low temperatures of -200°C (such as silicones) to avoid embrittlement and cracking at low temperatures; low-temperature welding rods must be used for welding metal parts (such as ER316L welding wire for 316L stainless steel).

[0047] Leakage test: After the compounding is completed, the flow channel sealing is tested by a helium mass spectrometer leak detector to ensure that there is no leakage of liquid nitrogen (leakage rate ≤ 1×10⁻ 9 Pa・m³ / s).

[0048] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. It comprises an outer layer component and a coolant flow pipe (5) located inside the outer layer component, characterized in that: A flow channel for cooling liquid flow is provided between the outer wall surface of the cooling liquid flow pipe (5) and the outer layer component. A plurality of groups of conductive components are equidistantly provided inside the cooling liquid flow pipe (5). A plurality of groups of wire cores (15) are equidistantly arranged inside the conductive components. An intermediate reinforcing core (16) is provided between the plurality of groups of wire cores (15).

2. The high-efficiency transmission cable for ships based on superconducting materials according to claim 1, characterized in that: The wire core (15) is made of copper-based high-temperature superconducting material, and the copper-based high-temperature superconducting material includes any one of yttrium barium copper oxide, bismuth strontium calcium copper oxide, thallium barium calcium copper oxide or mercury barium calcium copper oxide.

3. The high-efficiency transmission cable for ships based on superconducting materials according to claim 2, characterized in that: The outer layer component comprises an outer rubber layer (1), an intermediate flame retardant layer (2) and a heat insulation layer (3), wherein the intermediate flame retardant layer (2) is compounded on the inner side of the outer rubber layer (1), and the heat insulation layer (3) is compounded on the inner side of the intermediate flame retardant layer (2), the outer rubber layer (1) is any one of chloroprene rubber, EPDM rubber or chlorinated polyethylene rubber, the intermediate flame retardant layer (2) is any one of an intumescent flame retardant material, a composite formed by glass fiber cloth and a flame retardant adhesive coating or a ceramic silicone rubber belt, and the heat insulation layer (3) is any one of aerogel felt, a multilayer insulation material or a rigid polyurethane foam.

4. The high-efficiency transmission cable for ships based on superconducting materials according to claim 3, characterized in that: The flow channel includes annular grooves (6) equidistantly provided on the surface of the coolant flow tube (5) and a plurality of strip-shaped connecting channels (7) provided on the surface of the coolant flow tube (5), wherein the plurality of strip-shaped connecting channels (7) are respectively located between two adjacent annular grooves (6), and the strip-shaped connecting channels (7) are connected to the two adjacent annular grooves (6), and circular holes (4) are provided at both ends of the outer layer component, and the circular holes (4) on both sides respectively correspond to the positions of the annular grooves (6) at the two ends of the coolant flow tube (5).

5. The high-efficiency transmission cable for ships based on superconducting materials according to claim 4, characterized in that: The conductive component comprises an annular connection component (10), multiple groups of inner wall protrusions (11) and an inner annular component (12), wherein the inner side of the annular connection component (10) is fixedly mounted with the multiple groups of inner wall protrusions (11), and the inner annular component (12) is fixedly mounted at the ends of the multiple groups of inner wall protrusions (11), and multiple groups of wire cores (15) are arranged on the inner side of the inner annular component (12), and the position of the annular connection component (10) corresponds to the inner and outer positions of the annular groove (6).

6. The high-efficiency transmission cable for ships based on superconducting materials according to claim 5, characterized in that: The cooling liquid flow pipe (5) is provided with a plurality of connection holes (8) at positions corresponding to the annular groove (6), and the annular connection assembly (10) is integrally formed with a heat conduction protrusion (9) at positions corresponding to the connection holes (8), and the heat conduction protrusion (9) is located inside the connection hole (8).

7. The high-efficiency transmission cable for ships based on superconducting materials according to claim 6, characterized in that: The inner sides of the multiple groups of inner ring components (12) are connected in series via multiple strip-shaped connecting blocks (13), and each strip-shaped connecting block (13) is connected in series with the multiple groups of inner ring components (12). An annular tube (14) is fixedly mounted on one end of the strip-shaped connecting block (13), and the wire core (15) is arranged inside the annular tube (14), and the annular tube (14) wraps the wire core (15).

8. The high-efficiency transmission cable for ships based on superconducting materials according to claim 7, characterized in that: An intermediate reinforcement core (16) is provided between the multiple groups of annular tubes (14).

9. A method for preparing a high-efficiency transmission cable for ships based on superconducting materials, according to any one of claims 1 to 8, characterized in that: Includes the following: Step 1: prefabrication of the coolant flow pipe (5); Seamless pipe is used as base material and processed into straight pipe of required diameter through cold rolling or extrusion process; Using a CNC lathe to machine annular grooves (6) at equal intervals on the outer wall of the pipe; Processing a strip-shaped connecting channel (7) by laser cutting or milling to connect adjacent annular grooves (6); A connecting hole (8) is machined at a position corresponding to the annular groove (6) using a drilling machine, and the hole diameter matches the heat conduction protrusion (9) of the annular connecting component (10); Electrolytic polishing of the inner and outer walls of the pipe; Step 2: Pretreatment of the insulation layer (3): If it is aerogel felt or multi-layer insulation material, it is cut into a coil that matches the length of the coolant flow pipe (5) and the width is slightly larger than the circumference of the pipe; If it is a rigid polyurethane foam, it is processed into a tubular shape by molding, and the inner diameter is slightly larger than the outer diameter of the coolant flow pipe (5); Step 3: Composite molding: Flexible insulation layer: Fix the coolant flow pipe (5) on the rotating fixture, and evenly coat the outer wall with low-temperature curing silicone rubber adhesive; Start the rotary tooling and simultaneously spirally wrap the insulation layer coil around the outer wall of the pipe. Adhesive is used to bond the overlapped parts to ensure there are no wrinkles or bubbles. After winding is completed, it is cured at room temperature for one day to form a "thermal insulation layer-coolant flow pipe" complex; Hard insulation layer: The pre-treated coolant flow pipe (5) is placed in the mold as an insert using an injection molding composite process; Inject molten polyurethane foam raw material into the mold to fill the gap between the pipe and the mold; Step 4: Compounding the middle flame retardant layer (2) and the outer rubber layer (1) in sequence on the outside of the heat insulation layer (3); Step 5: Assemble the inner ring component (12), the strip connecting block (13), the ring tube (14) and the wire core (15) according to the design, and fill the middle reinforcing core (16) between the ring tubes (14) to complete the preparation of the overall cable.

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