Wear-resistant anti-bending cable

Abstract

The invention discloses a wear-resistant anti-bending cable, and belongs to the technical field of cable manufacturing. The invention discloses a manufacturing method of a wear-resistant anti-bending cable. The manufacturing method comprises the following steps: S1, preparing a conductor layer; s2, forming an inner sheath layer; s3, constructing a shape memory skeleton layer; s4, forming a high-modulus braid layer; s5, a segmented flexible fin buffer layer is formed; s6, preparing an outer sheath and a surface self-lubricating microcapsule layer; and S7, cooling, shaping and detecting. The polycaprolactone-polyurethane blended shape memory polymer (SMP) is introduced into the sheath layer, so that the compactness and permeability resistance of the material are remarkably improved. The polycaprolactone chain segment provides flexibility and low-temperature toughness, the polyurethane chain segment endows high strength and chemical stability, the polycaprolactone chain segment and the polyurethane chain segment are blended to form a multi-phase interpenetrating structure, permeation channels of oxygen, moisture and corrosion ions are effectively blocked, and the sheath layer can still keep excellent protection capability in a long-term high-humidity, high-salt and high-temperature environment.

Description

Technical Field

[0001] This invention relates to the field of cable manufacturing technology, and more specifically, to a wear-resistant and bend-resistant cable. Background Technology

[0002] As a critical carrier for energy transmission and information transmission, the long-term operational stability of power cables directly affects the safety and reliability of power systems. Existing cables are susceptible to corrosion, temperature variations, mechanical stress, and external chemical media in complex environments, leading to insulation degradation, decreased conductivity, and even short circuits and fractures. Especially in marine environments, chemical plant areas, and high-humidity or high-salt environments, the cable's metallic conductor and sheath are constantly exposed to corrosive media, resulting in localized electrochemical corrosion, microcrack propagation, and interface peeling, significantly shortening the cable's service life.

[0003] Currently, commonly used corrosion-resistant cables achieve basic protection primarily by coating the metal conductor with a thermoplastic resin sheath such as polyethylene (PE), polyvinyl chloride (PVC), or polypropylene (PP). While this structure provides some moisture resistance and insulation, its interfacial bonding is weak and its thermal aging performance is poor. Under alternating temperature differences or mechanical bending conditions, the sheath layer is prone to peeling and cracking. Furthermore, these conventional resin materials have limited resistance to ultraviolet light, ozone, and acid / alkali corrosion, making them unsuitable for long-term operation. Some modification schemes attempt to introduce fluorocarbon copolymers or silane coupling agents to enhance weather resistance, but these often suffer from complex processes, high costs, or reduced mechanical strength.

[0004] Furthermore, traditional cable sheath materials are mostly static structural materials, unable to adaptively respond to environmental stimuli. For example, when subjected to increased temperature, mechanical deformation, or external impact, the materials do not exhibit repair or structural recovery behavior, leading to localized stress concentration and fatigue damage accumulation. As power facilities develop towards intelligence and complex environments, there is an urgent need for a cable material system that combines high strength, corrosion resistance, aging resistance, and intelligent response characteristics. Summary of the Invention

[0005] The purpose of this invention is to provide a wear-resistant and bend-resistant cable to solve the problems mentioned in the background art.

[0006] A wear-resistant and bend-resistant cable, comprising, from the outside in, the following components arranged sequentially: Outer sheath layer: formed by blending and modifying thermoplastic polyurethane (TPU) matrix, silanized graphene nanosheets, nano-silica particles and grafted maleic anhydride polyolefin elastomer, with a graphene mass fraction of 1-5 wt%, an average sheet diameter of 0.5-3 μm, a thickness of 1-5 nm, and treated with KH-550 coupling agent. The nano-SiO2 content is 2-4 wt%, and the average particle size is 20-60 nm; The toughening agent is added at a rate of 1–3 wt%; the toughening agent comprises the following components (by weight): Maleic anhydride-grafted polyolefin elastomer (POE-g-MA): 50-70 parts; Thermoplastic polyurethane elastomer (TPU): 20-30 parts; Ethylene-octene copolymer (POE): 10-20 parts; Optional additives include 1 to 3 parts of compatibilizer (such as SEBS-g-MAH) to enhance the interfacial bonding between the polar SMP matrix and the non-polar elastomer.

[0007] The outer sheath has a thickness of 1.0–1.8 mm, a tensile strength ≥45 MPa, and a thermal conductivity of 0.35–0.60 W / m·K. Surface self-lubricating microcapsule layer: disposed within a range of 0.1–0.3 mm on the surface of the outer sheath, the microcapsule wall material is polyurea-polyurethane copolymer, the core material is polydimethylsiloxane or fluorinated paraffin lubricant, the average particle size is 10–50 μm, and the distribution density is 100–300 particles / mm. 2 , It automatically releases the lubricating medium when there is friction or wear or when the temperature rises, forming a self-healing low-friction film; Segmented flexible rib buffer layer: periodically distributed along the cable axis, the ribs are formed of shape memory polymer or TPE material, the shape memory polymer is a blend of polycaprolactone and polyurethane copolymer, the rib height is 0.4 to 0.8 times the thickness of the outer sheath, the spacing is 0.5 to 2 mm, the glass transition temperature of the shape memory polymer is 45 to 60°C, and it can recover its original shape under thermal excitation to buffer bending stress; High-modulus braided reinforcement layer: formed by cross-weaving of ultra-high molecular weight polyethylene (UHMWPE) or aramid 1414 fibers, with a weaving angle of 20° to 28°, a coverage of 60 to 75%, and a tensile modulus ≥ 60 GPa; Shape memory skeleton layer: composed of several nickel-titanium alloy wires with a wire diameter of 0.15-0.5 mm, a preset recovery strain of 3-8%, and a phase transformation temperature of 40-55℃; The alloy wire can be wound in a spiral shape, with a pitch of 0.5 to 1.5 times the outer diameter of the cable; Inner sheath layer: formed of polytetrafluoroethylene (PTFE) or polyetheretherketone (PEEK), with a thickness of 0.2-0.5 mm, serving as insulation and anti-friction function; Conductor layer: It is made of several strands of annealed softened copper wire or silver-plated copper wire, with a single wire diameter of 0.05 to 0.15 mm and a total number of strands ≥ 120. It adopts a seven-bundle or nineteen-bundle stranded wire structure to ensure a dynamic bending life of ≥ 500,000 times with a flexible structure.

[0008] Preferably, the manufacturing process of the wear-resistant and bend-resistant cable includes the following steps: S1. Prepare the conductor layer; S2, forming the inner sheath layer; S3. Construct a shape memory skeleton layer; S4. Form a high-modulus braided layer; S5. Molded segmented flexible rib buffer layer; S6. Preparation of outer sheath and surface self-lubricating microcapsule layer; S7. Cooling, shaping, and testing.

[0009] Preferably, in step S1, the preparation of the conductor layer includes: degreasing and cleaning a single-strand copper wire or a silver-plated copper wire, annealing it to 350-380°C to soften it; and stranding it using a multi-strand stranding machine in a “7×19” structure, with a total of 120-228 strands. The diameter of a single strand is controlled at 0.05–0.15 mm; the outermost strand is tin-plated to a thickness of 0.02 mm to prevent oxidation and improve solderability.

[0010] Preferably, in step S2, the inner sheath layer is coated onto the outer surface of the conductor by single-screw extrusion: the material is PTFE or PEEK; the extrusion temperature is controlled at 340-360℃, and the extrusion speed is 2-3m / min; it is cooled and formed by vacuum sizing sleeve, and the thickness is controlled at 0.3-0.5mm; the surface roughness Ra of the inner sheath is ≤0.4μm to reduce interlayer friction.

[0011] Preferably, in step S3, the preparation of the shape memory skeleton layer includes: selecting a nickel-titanium alloy wire with a nickel content of 55-56 at% and a titanium content of 44-45 at%; uniformly winding it around the outer surface of the inner sheath with a helical pitch of 0.5-1.5 times the outer diameter of the cable; setting the pre-strain to 3-8% and shaping it through thermal excitation at 55°C; covering it with a TiO2 insulating film with a thickness of 5-20 μm for protection against electro-corrosion; and fixing both ends to form a continuous shape memory skeleton.

[0012] Preferably, in step S4, the high-modulus braided layer is formed using a three-dimensional multi-axis braiding process: using UHMWPE or aramid 1414 fiber with a linear density of 800-1500D; a braiding angle of 20°-28° and a coverage of 60-75%; after braiding, it is cured at 120°C for 30 minutes and then coated with an epoxy-silane composite resin adhesive to enhance the interlayer bonding.

[0013] Preferably, in step S5, the segmented flexible rib layer is formed by compression molding: TPE or shape memory polymer is selected; the mold cavity is designed with a rib spacing of 0.5-2mm and a height of 0.4-0.8 times the thickness of the outer sheath; the molding temperature is 160-180℃, and the pressure is held for 15-20 seconds; periodic gaps are formed by laser etching to achieve a partitioned flexible structure; The shape memory polymer is formed by copolymerizing polycaprolactone and polyurethane, and its preparation method includes: 1) reacting polycaprolactone diol and isocyanate at 70-90°C to obtain PU prepolymer; 2) melting and mixing the PU prepolymer with the remaining PCL in a ratio of 60-80:40-20wt%; 3) molding and cooling to solidify through a mold to obtain a shape memory polymer with a glass transition temperature of 45-60°C.

[0014] Preferably, in step S6, the outer sheath layer and the surface self-lubricating microcapsule layer are formed in one step using a twin-screw co-extrusion process, the steps of which include: TPU, graphene, nano-SiO2 and toughening agent are mixed in proportion and kneaded at 200 rpm and 180-210℃ for 10 min to form a uniform composite melt. The prepared lubricating microcapsules (average particle size 10-50 μm) were added to the outer melt at a ratio of 1-2 wt% and injected through a secondary feed port to prevent capsule rupture. It is co-extruded using a double-layer concentric mold, with an outer 0.3mm thick self-lubricating layer and an inner modified TPU layer; After being shaped by a combination of air cooling and water cooling, a micro-protrusion array (height 10-50μm, spacing 100-300μm) is formed on the surface, improving anti-slip and wear resistance.

[0015] Preferably, in step S7, the cable undergoes segmented water cooling (25°C, 3m cooling tank) and hot air drying (60°C, 10min) for shaping; subsequently, the following tests are performed: Insulation resistance ≥ 500 MΩ·km; Dynamic bending test: Bending radius is 4 times the outer diameter, and the number of cycles is ≥500,000 without breakage; Wear test (Taber method, CS-17 wheel, 1kg load, 1000 rpm): Wear amount ≤ 0.5mg / cm² 2 ; The cable outer diameter tolerance is controlled within ±0.05mm.

[0016] Preferably, the outer sheath layer may be further doped with 0.5 to 1.0 wt% silicon carbide nanoparticles to improve surface microhardness (≥85 Shore D), and the shape memory skeleton layer can be rapidly rebounded by infrared heating or current excitation, so that the cable can maintain shape stability in high-frequency bending environment.

[0017] Compared with the prior art, the advantages of this invention are: (1) By introducing polycaprolactone-polyurethane blended shape memory polymer (SMP) into the sheath layer, the density and impermeability of the material are significantly improved. Polycaprolactone segments provide flexibility and low-temperature toughness, while polyurethane segments impart high strength and chemical stability. The blending of the two forms a multi-interpenetrating structure, which effectively blocks the penetration channels of oxygen, moisture and corrosive ions. At the same time, the compounded nano-alumina particles further improve the thermo-oxidative stability, enabling the sheath layer to maintain excellent protective capabilities under long-term high humidity, high salt and high temperature environments.

[0018] (2) When the cable is subjected to mechanical bending, local crushing or external thermal shock, the shape memory polymer in the sheath can undergo directional recovery of molecular chain segments at a certain temperature, realizing crack closure and self-repair of micro-damage. This characteristic can significantly reduce the problem of decreased insulation performance of the cable caused by the propagation of micro-cracks, thereby extending the overall service life and reducing the maintenance frequency.

[0019] (3) Through the synergistic effect of molecular structure design and composite filling, the cable sheath of the present invention is superior to the traditional polyethylene sheath in terms of tensile strength, elongation at break, and tear strength. Test results show that the tensile strength of the sheath material in the embodiment is increased by about 30%, and the elongation at break is increased by about 25%, which greatly enhances the structural stability while maintaining good flexibility. Attached Figure Description

[0020] Figure 1 This is a flowchart of the cable manufacturing steps of the present invention. Detailed Implementation

[0021] Example 1 Material preparation Conductor material: Annealed and softened copper wire, single strand diameter 0.10mm, total number of strands 120.

[0022] Inner sheath material: polytetrafluoroethylene (PTFE) granules.

[0023] Shape memory skeleton material: nickel-titanium alloy wire, diameter 0.3mm, Ni 55at%, Ti 45at%, preset recovery strain 5%, phase transformation temperature 50℃.

[0024] Flexible rib material: shape memory polymer, formed by copolymerization of polycaprolactone (PCL, molecular weight 9000) and polyurethane (PU), with a glass transition temperature of 50°C.

[0025] High modulus braided material: UHMWPE fiber, linear density 1000D.

[0026] Outer sheath material: thermoplastic polyurethane (TPU) matrix, incorporating silanized modified graphene (2wt%, average sheet diameter 1μm, thickness 3nm, treated with KH-550), nano-SiO2 (3wt%, particle size 40nm) and grafted maleic anhydride polyolefin elastomer toughening agent (2wt%).

[0027] Microencapsulated lubricant: polyurea-polyurethane shell, polydimethylsiloxane core, average particle size 30μm, addition amount 1.5wt%.

[0028] Preparation steps S1 conductor preparation: The copper wire is degreased and cleaned, and then annealed to 360°C in air to soften it; it is stranded in a “7×19” structure using a multi-bundle stranding machine, with a total of 120 strands; the outermost strand is tin-plated with 0.02mm to improve oxidation resistance and solderability.

[0029] S2 Inner Sheath Formation: PTFE particles are coated onto the conductor surface using a single-screw extruder at an extrusion temperature of 350℃ and an extrusion speed of 2.5m / min. The inner sheath is formed using a vacuum sizing sleeve with a thickness of 0.4mm and a surface roughness Ra≈0.35μm.

[0030] S3 Shape Memory Skeleton Layer Construction: Nickel-titanium alloy wire is spirally wound on the outer surface of the inner sheath with a pitch of 1 times the cable outer diameter; a pre-strain of 5% is applied, and deformation is achieved through thermal excitation at 55℃; a 5μm thick TiO2 insulating film is sprayed onto the surface, and the two ends are fixed to form a continuous skeleton.

[0031] S4 High Modulus Braided Layer Formation: Using a three-dimensional multi-axis braiding process, UHMWPE fibers are cross-woven onto the outside of the skeleton layer; the braiding angle is 25°, the coverage is 70%, and after weaving, it is cured at a constant temperature of 120℃ for 30 minutes, and then coated with epoxy-silane composite adhesive to enhance the bonding strength.

[0032] S5 segmented flexible rib buffer layer molding: The shape memory polymer is heated to 170℃ and injected into the mold cavity to form ribs; the height of the ribs is 0.6 times the thickness of the outer sheath, and the spacing is 1mm; the molding temperature is 170℃ and the pressure is held for 20 seconds; periodic gaps are formed by laser etching to achieve partitioned flexible buffering.

[0033] S6 outer sheath and self-lubricating microcapsule layer co-extrusion: TPU, graphene, nano-SiO2 and toughening agent are mixed in a twin-screw mixer at 200 rpm for 10 minutes; 1.5 wt% of microcapsule lubricant is added through a secondary feed port to avoid breakage; double-layer concentric mold co-extrusion molding, the outer self-lubricating microcapsule is 0.3 mm thick and the inner layer is modified TPU; after air cooling + water cooling for shaping, a micro-protrusion array (height 30 μm, spacing 200 μm) is formed on the surface.

[0034] S7 Cooling and Testing: The cable is water-cooled for 3 meters in a 25℃ water bath and dried with hot air at 60℃ for 10 minutes; insulation resistance test ≥500MΩ·km; dynamic bending test: bending radius is 4 times the outer diameter, and the number of cycles ≥500,000 without breakage; abrasion test (Taber method, CS-17 wheel, 1kg load, 1000 revolutions) abrasion amount 0.45mg / cm 2 Cable outer diameter tolerance ±0.05mm.

[0035] Example 2 Material preparation Conductor material: Annealed and softened silver-plated copper wire, single strand diameter 0.08mm, total number of strands 144.

[0036] Inner sheath material: Polyetheretherketone (PEEK) particles.

[0037] Shape memory skeleton material: nickel-titanium alloy wire, diameter 0.25mm, Ni 55.5at%, Ti 44.5at%, preset recovery strain 4%, phase transformation temperature 48℃.

[0038] Flexible rib material: shape memory polymer, formed by copolymerization of PCL (molecular weight 8500) and PU, with a glass transition temperature of 48℃.

[0039] High modulus braiding material: Aramid 1414 fiber, linear density 1200D.

[0040] Outer sheath material: TPU matrix, incorporating silanized modified graphene (3wt%, sheet diameter 2μm, thickness 4nm, treated with KH-550), nano-SiO2 (2.5wt%, particle size 50nm) and grafted maleic anhydride polyolefin elastomer toughening agent (1.5wt%).

[0041] Microencapsulated lubricant: polyurea-polyurethane shell, fluorinated paraffin core, average particle size 25μm, added amount 1.2wt%.

[0042] Preparation steps S1 conductor preparation: copper wire is degreased and cleaned, then annealed to 355℃ for softening; 144 strands are stranded in a “7×19” structure; the outermost strand is tin-plated to 0.02mm.

[0043] S2 Inner Sheath Formation: PEEK is used to coat the conductor using a single-screw extruder at an extrusion temperature of 355℃ and a speed of 2.0m / min; the cooling and forming thickness is 0.35mm, Ra≈0.38μm.

[0044] S3 shape memory skeleton layer construction: nickel-titanium wire spiral winding pitch is 0.8 times the cable outer diameter; pre-strain 4%, shaped by thermal excitation at 50℃; TiO2 insulating film thickness 10μm.

[0045] S4 high modulus braided layer formation: aramid fibers are cross-woven at an angle of 22° with a coverage of 65%, cured at 120°C for 35 minutes, and coated with epoxy-silane adhesive.

[0046] S5 segmented flexible rib buffer layer molding: shape memory polymer is injected into the mold cavity, with a height of 0.5 times the outer sheath thickness and a spacing of 1.2 mm; molding temperature is 165℃, holding pressure for 18 seconds; laser etching forms periodic gaps.

[0047] S6 outer sheath and self-lubricating microcapsule layer co-extrusion: TPU, graphene, nano SiO2 and toughening agent are mixed at 200rpm for 12 minutes; 1.2wt% microcapsule lubricant is added; co-extrusion molding, outer layer thickness 0.28mm; after air cooling + water cooling for shaping, the micro-protrusion height is 28μm and the spacing is 180μm.

[0048] S7 Cooling and Shaping Test: Water cooling at 25℃ for 3m, hot air drying at 60℃ for 12 minutes; Insulation resistance ≥550MΩ·km; Dynamic bending ≥500,000 times without wire breakage; Wear loss 0.48mg / cm²; Outer diameter tolerance ±0.05mm.

[0049] Example 3 Material preparation Conductor material: Annealed and softened copper wire, single strand diameter 0.12mm, total number of strands 132.

[0050] Inner sheath material: PTFE granules.

[0051] Shape memory skeleton material: nickel-titanium alloy wire, diameter 0.35mm, Ni 55at%, Ti 45at%, preset recovery strain 6%, phase transformation temperature 52℃.

[0052] Flexible rib material: Shape memory polymer, formed by copolymerization of PCL (molecular weight 9500) and PU, with a glass transition temperature of 52℃.

[0053] High modulus braided material: UHMWPE fiber, linear density 1100D.

[0054] Outer sheath material: TPU matrix, incorporating silanized modified graphene (1.5wt%, sheet diameter 1.5μm, thickness 3nm), nano-SiO2 (3.5wt%, particle size 45nm), and toughening agent 2wt%.

[0055] Microencapsulated lubricant: polyurea-polyurethane shell, polydimethylsiloxane core, particle size 35μm, addition amount 1.8wt%.

[0056] Preparation steps S1: Copper wire annealed to 365℃, stranded into 132 strands, with an outer tin plating of 0.02mm.

[0057] S2: PTFE single-screw extrusion, temperature 350℃, speed 2.8m / min; thickness 0.42mm, Ra≈0.36μm.

[0058] S3: The pitch of the nickel-titanium wire spiral winding is 1.2 times the outer diameter of the cable; the pre-strain is 6%, and the heat excitation is set at 55℃; the TiO2 film is 8μm.

[0059] S4: UHMWPE fiber cross-weave, angle 24°, coverage 72%, cure for 30 minutes, apply epoxy-silane adhesive.

[0060] S5: Shape memory polymer molding, height 0.55 times the outer sheath thickness, spacing 1mm; temperature 175℃, pressure holding for 20 seconds; laser etching gap.

[0061] S6: TPU composite material is mixed at 200 rpm for 10 minutes; 1.8 wt% microcapsule lubricant is added; co-extruded, with an outer layer thickness of 0.32 mm, a micro-protrusion height of 32 μm, and a spacing of 210 μm.

[0062] S7: Water cooling at 25℃ for 3m; hot air drying at 60℃ for 10 minutes; insulation resistance ≥500MΩ·km; bending ≥500,000 times; wear loss 0.50mg / cm²; outer diameter tolerance ±0.05mm.

[0063] Example 4 Material preparation Conductor material: Annealed and softened silver-plated copper wire, single strand diameter 0.09mm, total number of strands 126.

[0064] Inner sheath material: PEEK granules.

[0065] Shape memory skeleton material: nickel-titanium alloy wire, diameter 0.28mm, Ni 55.2at%, Ti 44.8at%, preset recovery strain 5%, phase transformation temperature 49℃.

[0066] Flexible rib material: Shape memory polymer, formed by copolymerization of PCL (molecular weight 8800) and PU, with a glass transition temperature of 49℃.

[0067] High-modulus braiding material: Aramid 1414 fiber, linear density 1000D.

[0068] Outer sheath material: TPU matrix, incorporating silanized modified graphene (2.5wt%, sheet diameter 1.2μm, thickness 3nm), nano-SiO2 (3wt%, particle size 42nm), and toughening agent 2wt%.

[0069] Microencapsulated lubricant: polyurea-polyurethane shell, fluorinated paraffin core, particle size 28μm, addition amount 1.5wt%.

[0070] Preparation steps S1: Copper wire annealed to 358℃, stranded into 126 strands, with an outer tin plating of 0.02mm.

[0071] S2: PEEK single-screw extrusion, temperature 352℃, speed 2.3m / min; thickness 0.38mm, Ra≈0.37μm.

[0072] S3: Nickel-titanium wire spiral wound, pitch 0.9 times the outer diameter of the cable; pre-strain 5%, thermally excited at 50℃ for shaping; TiO2 film 6μm.

[0073] S4: Aramid fiber cross-weave, angle 23°, coverage 68%, cured at 120℃ for 30 minutes, coated with epoxy-silane adhesive.

[0074] S5: Shape memory polymer molding, height 0.58 times the outer sheath thickness, spacing 1.1mm; temperature 168℃, pressure holding 19 seconds; gap formed by laser etching.

[0075] S6: TPU composite material is mixed for 10 minutes, and 1.5wt% microcapsule lubricant is added; co-extruded, with an outer layer thickness of 0.30mm; micro-protrusion height of 30μm and spacing of 200μm.

[0076] S7: Water-cooled at 25℃ for 3m, hot air dried at 60℃ for 10 minutes; insulation resistance ≥520MΩ·km; dynamic bending ≥500,000 times; wear loss 0.46mg / cm²; outer diameter tolerance ±0.05mm.

[0077] Comparative Example 1 Material preparation Conductor material: Annealed and softened copper wire, single strand diameter 0.10 mm, total number of strands 120.

[0078] Inner sheath material: PTFE granules.

[0079] High modulus braided materials: None.

[0080] Outer sheath material: TPU matrix, without nanofillers or toughening agents.

[0081] Microencapsulated lubricant: None.

[0082] Flexible ribs and skeleton layer: None.

[0083] Preparation steps S1 conductor preparation: copper wire is degreased and cleaned, and annealed to 360℃ to soften; stranded in a “7×19” structure, with a total of 120 strands; the outermost layer is tin-plated to 0.02 mm.

[0084] S2 Inner Sheath Formation: PTFE particles are extruded through a single screw to coat the conductor at an extrusion temperature of 350℃ and a speed of 2.5m / min; the thickness is 0.4 mm and the surface roughness Ra≈0.35 μm.

[0085] S3 Outer Sheath Formation: Pure TPU is extruded through a single screw, with a thickness of 1.2 mm; extrusion temperature is 200℃, followed by cooling and molding.

[0086] S4 Cooling and Shaping Test: Water cooling at 25℃ for 3 m, hot air drying at 60℃ for 10 minutes; Insulation resistance ≥500 MΩ·km; Dynamic bending test (bending radius 4 times outer diameter) cycles ≥100,000; Wear loss 0.8 mg / cm²; Outer diameter tolerance ±0.05 mm.

[0087] Comparative Example 2 Material preparation Conductor material: Annealed and softened copper wire, single strand diameter 0.12 mm, total number of strands 132.

[0088] Inner sheath material: PEEK granules.

[0089] High modulus braided material: ordinary polyimide fiber, linear density 800D.

[0090] Outer sheath material: TPU matrix with a small amount of toughening agent (1 wt%), no graphene or nano SiO2.

[0091] Microencapsulated lubricant: None.

[0092] Flexible ribs and skeleton layer: None.

[0093] Preparation steps S1 conductor preparation: copper wire is degreased and cleaned, annealed to 355℃ to soften; stranded in a “7×19” structure, with a total of 132 strands; outer layer tin-plated 0.02 mm.

[0094] S2 Inner Sheath Layer Formation: PEEK single-screw extrusion, temperature 355℃, speed 2.0 m / min; thickness 0.38 mm, Ra≈0.37 μm.

[0095] S3 Outer Sheath Formation: TPU + toughening agent is formed by single-screw extrusion, with a thickness of 1.3 mm; extrusion temperature is 205℃, followed by cooling and shaping.

[0096] S4 Cooling and Shaping Test: Water cooling at 25℃ for 3 m, hot air drying at 60℃ for 12 minutes; Insulation resistance ≥ 500 MΩ·km; Dynamic bending test cycles approximately 150,000; Wear loss 0.75 mg / cm² 2Outer diameter tolerance ±0.05 mm.

[0097] To verify the effectiveness of the wear-resistant and bend-resistant cables in Examples 1-4 and Comparative Examples 1-2, the following experiments were designed: 1.1 Sample Preparation Example: Each of Examples 1 to 4 prepares a cable with a length of 2 m.

[0098] Comparative Examples: Prepare one cable with a length of 2 m for each of Comparative Examples 1 and 2.

[0099] At least three strips should be prepared for each sample to ensure data reproducibility.

[0100] 1.2 Dynamic Bending Performance Test Fix the cable on the bending tester, and bend it with a radius of 4 times the outer diameter of the cable.

[0101] Bending frequency 1 Hz, continuously cycled until the cable breaks or reaches 500,000 cycles.

[0102] Record the number of loops and the location of the disconnection.

[0103] 1.3 Wear performance test (Taber wear method) Using a Taber abrasion tester, with a load of 1 kg, a CS-17 grinding wheel, and a rotation speed of 1000 rpm.

[0104] The wear amount (mg / cm²) was measured for each sample.

[0105] Take the average of the three samples.

[0106] 1.4 Insulation Resistance Test Use an insulation resistance meter to measure the cable insulation resistance (MΩ·km) with a voltage of 500 V applied.

[0107] Record the average value of the three samples.

[0108] 1.5 Outer diameter and structural stability check Use vernier calipers to measure the cable's outer diameter tolerance (mm).

[0109] The structural stability is assessed by observing the integrity of the outer sheath, skeleton layer, and rib structure after the cable is bent.

[0110] The experimental results are shown in Table 1: Table 1 Summary of experimental results: Dynamic bending performance: Examples 1-4 showed excellent flexibility and bending resistance with no breakage after ≥500,000 cycles at a bending radius of 4 times the outer diameter.

[0111] Comparative Examples 1-2 could only withstand 100,000 to 150,000 cycles before breaking, proving that the bending life of traditional structure cables is far lower than that of this invention.

[0112] Abrasion performance: The abrasion amount in the example is about 0.43 to 0.46 mg / cm², while the abrasion amount in the comparative example is 0.75 to 0.80 mg / cm².

[0113] The microcapsule self-lubricating layer and the modified TPU outer sheath significantly reduced friction and wear.

[0114] Insulation performance: The insulation resistance of all samples was ≥500 MΩ·km, but the insulation resistance of the examples was slightly higher than that of the comparative examples, indicating that the composite structure did not affect the insulation performance.

[0115] Structural stability and outer diameter tolerance: In the example, the skeleton, ribs and outer sheath structure remained intact after high-frequency bending; the comparative sample showed cracks or deformation in the outer sheath, indicating insufficient structural stability.

[0116] Conclusion: The wear-resistant and bend-resistant cable of the present invention significantly improves bending life and wear resistance through innovative structures such as shape memory skeleton, segmented flexible ribs and self-lubricating microcapsules, which is superior to conventional cables (Comparative Examples 1-2).

[0117] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples of the present invention and are not intended to limit the present invention. Various changes and modifications can be made to the present invention without departing from the spirit and scope thereof, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A wear-resistant and bend-resistant cable, characterized in that, Including those set sequentially from the outside in: Outer sheath layer: formed by blending and modifying thermoplastic polyurethane (TPU) matrix, silanized graphene nanosheets, nano-silica particles and grafted maleic anhydride polyolefin elastomer, with a graphene mass fraction of 1-5 wt%, an average sheet diameter of 0.5-3 μm, a thickness of 1-5 nm, and treated with KH-550 coupling agent. The nano-SiO2 content is 2-4 wt%, and the average particle size is 20-60 nm; The toughening agent is added at a rate of 1–3 wt%; The outer sheath has a thickness of 1.0–1.8 mm, a tensile strength ≥45 MPa, and a thermal conductivity of 0.35–0.60 W / m·K. Surface self-lubricating microcapsule layer: disposed within a range of 0.1–0.3 mm on the surface of the outer sheath, the microcapsule wall material is polyurea-polyurethane copolymer, the core material is polydimethylsiloxane or fluorinated paraffin lubricant, the average particle size is 10–50 μm, and the distribution density is 100–300 particles / mm. 2 ; Segmented flexible rib buffer layer: periodically distributed along the cable axis, the ribs are formed of shape memory polymer or TPE material, the shape memory polymer is a blend of polycaprolactone and polyurethane copolymer, the rib height is 0.4 to 0.8 times the thickness of the outer sheath, the spacing is 0.5 to 2 mm, the glass transition temperature of the shape memory polymer is 45 to 60°C, and it can recover its original shape under thermal excitation to buffer bending stress; High-modulus braided reinforcement layer: formed by cross-weaving of ultra-high molecular weight polyethylene (UHMWPE) or aramid 1414 fibers, with a weaving angle of 20° to 28°, a coverage of 60 to 75%, and a tensile modulus ≥ 60 GPa; Shape memory skeleton layer: composed of several nickel-titanium alloy wires with a wire diameter of 0.15-0.5 mm, a preset recovery strain of 3-8%, and a phase transformation temperature of 40-55℃; The alloy wire can be wound in a spiral shape, with a pitch of 0.5 to 1.5 times the outer diameter of the cable; Inner sheath layer: formed of polytetrafluoroethylene (PTFE) or polyetheretherketone (PEEK), with a thickness of 0.2-0.5 mm, serving as insulation and anti-friction function; Conductor layer: It is made of several strands of annealed and softened copper wire or silver-plated copper wire, with a single strand diameter of 0.05 to 0.15 mm and a total number of strands ≥ 120. It adopts a seven-bundle or nineteen-bundle stranded wire structure.

2. The wear-resistant and bend-resistant cable according to claim 1, characterized in that, The manufacturing process of the wear-resistant and bend-resistant cable includes the following steps: S1. Prepare the conductor layer; S2, forming the inner sheath layer; S3. Construct a shape memory skeleton layer; S4. Form a high-modulus braided layer; S5. Molded segmented flexible rib buffer layer; S6. Preparation of outer sheath and surface self-lubricating microcapsule layer; S7. Cooling, shaping, and testing.

3. The wear-resistant and bend-resistant cable according to claim 2, characterized in that, In step S1, the preparation of the conductor layer includes: degreasing and cleaning a single-strand copper wire or a silver-plated copper wire, annealing it to 350-380°C to soften it; and stranding it using a multi-strand stranding machine in a "7×19" structure, with a total of 120-228 strands. The diameter of a single strand is controlled at 0.05–0.15 mm; the outermost strand is tin-plated to a thickness of 0.02 mm to prevent oxidation and improve solderability.

4. The wear-resistant and bend-resistant cable according to claim 2, characterized in that, In step S2, the inner sheath layer is coated onto the outer surface of the conductor by single-screw extrusion: the material is PTFE or PEEK; the extrusion temperature is controlled at 340-360℃, and the extrusion speed is 2-3m / min; it is cooled and formed by vacuum sizing sleeve, and the thickness is controlled at 0.3-0.5mm; the surface roughness Ra of the inner sheath is Ra≤0.4μm to reduce interlayer friction.

5. The wear-resistant and bend-resistant cable according to claim 2, characterized in that, In step S3, the preparation of the shape memory skeleton layer includes: selecting nickel-titanium alloy wire with a nickel content of 55-56 at% and a titanium content of 44-45 at%; uniformly winding it around the outer surface of the inner sheath with a helical pitch of 0.5-1.5 times the outer diameter of the cable; setting the pre-strain to 3-8% and shaping it through thermal excitation at 55℃; covering it with a TiO2 insulating film with a thickness of 5-20 μm for protection against electro-corrosion; and fixing both ends to form a continuous shape memory skeleton.

6. The wear-resistant and bend-resistant cable according to claim 2, characterized in that, In step S4, the high-modulus braided layer is formed using a three-dimensional multi-axis braiding process: using UHMWPE or aramid 1414 fiber with a linear density of 800-1500D; a braiding angle of 20°-28° and a coverage of 60-75%; after braiding, it is cured at 120°C for 30 minutes and then coated with an epoxy-silane composite resin adhesive to enhance the interlayer bonding.

7. The wear-resistant and bend-resistant cable according to claim 2, characterized in that, In step S5, the segmented flexible rib layer is formed by compression molding: TPE or shape memory polymer is selected; the mold cavity is designed with a rib spacing of 0.5-2mm and a height of 0.4-0.8 times the thickness of the outer sheath; the molding temperature is 160-180℃ and the holding pressure is 15-20 seconds; periodic gaps are formed by laser etching to achieve a partitioned flexible structure. The shape memory polymer is formed by copolymerizing polycaprolactone and polyurethane, and its preparation method includes: 1) reacting polycaprolactone diol and isocyanate at 70-90°C to obtain PU prepolymer; 2) melting and mixing the PU prepolymer with the remaining PCL in a ratio of 60-80:40-20wt%; 3) molding and cooling to solidify through a mold to obtain a shape memory polymer with a glass transition temperature of 45-60°C.

8. The wear-resistant and bend-resistant cable according to claim 2, characterized in that, In step S6, the outer sheath layer and the surface self-lubricating microcapsule layer are formed in one step using a twin-screw co-extrusion process. The steps include: TPU, graphene, nano-SiO2 and toughening agent are mixed in proportion and kneaded at 200 rpm and 180-210℃ for 10 min to form a uniform composite melt. The prepared lubricating microcapsules were added to the outer melt at a ratio of 1-2 wt% and injected through a secondary feed port to prevent capsule rupture. It is co-extruded using a double-layer concentric mold, with an outer 0.3mm thick self-lubricating layer and an inner modified TPU layer; The surface is formed by a dual-stage air-cooling and water-cooling process, which enhances its anti-slip and wear-resistant properties.

9. The wear-resistant and bend-resistant cable according to claim 2, characterized in that, In step S7, the cable undergoes segmented water cooling and hot air drying for shaping; subsequently, the following tests are performed: Insulation resistance ≥ 500 MΩ·km; Dynamic bending test: Bending radius is 4 times the outer diameter, and the number of cycles is ≥500,000 without breakage; Wear test wear amount ≤ 0.5 mg / cm 2 ; The cable outer diameter tolerance is controlled within ±0.05mm.

10. The cable and its manufacturing method according to any one of claims 1 to 9, characterized in that, The outer sheath layer can be further doped with 0.5 to 1.0 wt% silicon carbide nanoparticles to improve surface microhardness, and the shape memory skeleton layer can be rapidly rebounded by infrared heating or current excitation.

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