Fatigue fracture resistant drag chain cable and preparation method thereof

Abstract

The invention relates to the technical field of cables, and discloses an anti-fatigue-fracture drag chain cable and a preparation method thereof, and the anti-fatigue-fracture drag chain cable comprises at least one conductor formed by twisting a plurality of wires; the insulating layer wraps the conductor to form an insulating wire core; the outer sheath is wrapped outside the insulating wire core; the active management complexing agent is filled in gaps among the multiple strands of wires; the active management complexing agent comprises the following components: carrier base fluid; a lubrication supplement microcapsule; a crack repair microcapsule; the carrier base fluid consists of a main carrier base fluid and a non-covalent bond cross-linking agent; the main carrier base fluid is perfluoropolyether, and the non-covalent bond cross-linking agent is a trimesoyl-based supramolecular polymer. According to the invention, the complexing agent containing the lubricating and repairing microcapsules is filled between the conductors through a specific process, so that the active inhibition of fatigue damage is realized, and the anti-fatigue life of the cable is prolonged.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of cables, in particular to a drag chain cable with anti-fatigue fracture and a preparation method. BACKGROUND

[0002] The drag chain cable, as a power and signal transmission carrier connecting mobile units and fixed units in modern manufacturing equipment such as industrial automation equipment, robot systems, numerical control machine tools, etc., has extremely harsh operating environment. During equipment operation, the cable is housed in the drag chain system and subjected to high-frequency, large-stroke reciprocating bending, twisting and other complex motions. This continuous dynamic stress cycle makes the conductor material inside the cable prone to metal fatigue, accumulates damage and eventually leads to fatigue fracture, resulting in equipment downtime and affecting production continuity and stability. Therefore, developing a drag chain cable with high anti-fatigue fracture performance is an important technical direction to improve the reliability of high-end equipment.

[0003] To improve the mechanical life of the drag chain cable, the existing technology usually adopts a combination of various technical means. At the conductor level, high flexibility conductors made of more and finer single copper wires are commonly used to disperse bending stress. At the structural level, the internal stress distribution is made more uniform by optimizing the conductor twisting, pitch and direction of multiple insulated wire cores, and stress concentration is avoided. At the same time, at the material level, high-performance polymer materials such as thermoplastic polyurethane (TPU) or polyether polyurethane (PUR) with high wear resistance and high elasticity are widely used as insulation layers and outer sheaths to resist external mechanical wear and chemical corrosion. In some designs, lubricating oil or powdered filler is also filled between the conductor strands to reduce friction between the strands.

[0004] Although the existing technology improves the anti-fatigue performance of the cable to some extent by using high flexibility conductors and optimizing the structure, there are still some deficiencies: in long-term severe reciprocating motion, the simple filling of lubricating oil between the strands will be gradually squeezed out due to siphon effect and centrifugal effect, oxidized and degraded due to local temperature rise, or contaminated by metal particles generated by wear, resulting in an increase in the friction coefficient between the strands, thereby accelerating the initiation of fretting wear and fatigue cracks. More importantly, this passive lubrication method has no function to inhibit the expansion of the micro-cracks that have already been initiated. Once a micro-crack is formed on the surface of the conductor due to stress concentration, the crack will continue to expand irreversibly as a new stress concentration point in the subsequent stress cycle, until the conductor is completely broken. In addition, even if more advanced functional fillers (such as microcapsules) are introduced into the conductor gap, the huge mechanical extrusion force and shear force generated by the conventional cable conductor twisting process are enough to destroy these delicate structures during manufacturing, making them unable to maintain functional integrity in the final product. SUMMARY

[0005] The present application aims to provide an anti-fatigue fracture drag chain cable and a preparation method, which solves the problem of insufficient anti-fatigue performance and limited service life of the existing drag chain cable due to the lack of effective mechanism for continuously lubricating and actively repairing fatigue damage between conductor strands.

[0006] To achieve the above object, the present application is implemented by the following technical solutions: The present application provides an anti-fatigue fracture drag chain cable in the first aspect: The drag chain cable comprises at least one conductor and an insulating layer and an outer sheath wrapped outside the conductor in sequence. The conductor is twisted by multiple strands of wires to form an insulated core. In the microscopic gap between the multiple strands of wires, an active management composite agent is filled.

[0007] The active management composite agent is composed of the following components by weight: 100 parts of carrier base fluid, 5.9-14.3 parts of lubrication supplement microcapsules, 5.9-21.5 parts of crack repair microcapsules, and 1.2-4.3 parts of solid lubricant.

[0008] The carrier base fluid comprises a main carrier base fluid and a non-covalent crosslinking agent. The main carrier base fluid is perfluoropolyether, and the non-covalent crosslinking agent is a supramolecular polymer based on trihydroxybenzamidine. The non-covalent crosslinking agent makes the carrier base fluid have shear thickening properties, that is, its viscosity reversibly increases when subjected to a certain intensity of shear force.

[0009] The lubrication supplement microcapsules and the crack repair microcapsules are two functionally independent units: The lubrication supplement microcapsules have a low-viscosity lubricating oil as the core and gelatin and gum arabic as the wall material. The wall material has low mechanical strength and is designed to break under the weak stress generated by the normal reciprocating motion of the conductor to release the lubricating oil in the core for continuous lubrication and supplement between the wire strands, thereby reducing the friction between the strands.

[0010] The crack repair microcapsules have a cyanoacrylate monomer as the core and urea-formaldehyde resin modified polyurethane as the wall material. The wall material has high mechanical strength and toughness and is designed to break only under the action of the sharp stress concentration formed by the micro-cracks in the wire to release the repair agent in the core for filling and bonding the cracks, thereby inhibiting the propagation of the cracks.

[0011] The solid lubricant, such as hexagonal boron nitride or nano-sized polytetrafluoroethylene powder, is distributed between the strands as a primary lubricating medium.

[0012] In one embodiment, the drag chain cable can further comprise a central tensile element located at the center of the multiple insulated cores, which is composed of aramid fibers to increase the overall tensile performance of the cable.

[0013] The second aspect of the present application provides a method for preparing a fatigue fracture resistant drag chain cable: The method is used for preparing the fatigue fracture resistant drag chain cable as described above, and the process comprises the following steps: S1, preparing an active management composite agent; S2, pretreating the multiple wires; S3, filling the active management composite agent into the gaps of the multiple wires by using a vacuum infiltration method; S4, protective stranding the multiple wires after the infiltration to form a conductor; S5, insulating extruding the conductor to form an insulated wire core, and performing cable formation and outer sheath extrusion on the insulated wire core.

[0014] In step S1, by using a planetary stirring mixer, the predetermined proportion of the lubrication supplement microcapsules, the crack repair microcapsules and the solid lubricant are uniformly dispersed in the carrier base fluid at an ambient temperature of 25-40°C and a stirring speed of 50-100 rpm, and mixed for 30-60 minutes.

[0015] In steps S2 and S3, first, by using an atmospheric pressure plasma cleaning device, the multiple wires with a line speed of 10-20 m / min are cleaned on line at a power of 300-500 W.

[0016] Subsequently, the cleaned wires are introduced into a vacuum infiltration cavity, the vacuum degree of the cavity is extracted to 10-50 Pa, the active management composite agent preheated to 40-60°C is injected, and the infiltration is maintained for 5-15 minutes to ensure that the composite agent completely fills the gaps of the wires.

[0017] In step S4, the protective stranding is performed by using an online high-speed beam machine linked with the vacuum infiltration system. The stranding line speed is set to 80-150 m / min, and the stranding pitch is 8-12 times the outer diameter of the conductor after the stranding; by the combination of the line speed and the pitch, the composite agent is subjected to a high shear rate when passing through the stranding die; The non-covalent crosslinking agent in the carrier base fluid is acted under the shear rate, which causes the rheological state of the composite agent to be temporarily and reversibly changed from a low-viscosity flow state to a high-viscosity gel state; the formation of the gel state provides mechanical buffering for the microcapsules dispersed in the composite agent, preventing them from being physically damaged in the high-speed stranding process. After the completion of the stranding process, the shear force disappears, and the composite agent returns to the low-viscosity flow state.

[0018] In step S5, first, by using a wire and cable extruder, the conductor is insulating layer extruded at a temperature range of 170-220°C to form an insulated wire core; Then the planet type cabling machine is used to twist the multiple insulated cores into a cable with a pitch of 6-8 times of the diameter of the cable core; Finally, the pressure extrusion process is used to extrude the outer sheath of the cabled core at a temperature range of 180-220℃.

[0019] In summary, the present application includes at least one of the following beneficial technical effects: 1. The present application introduces an active management composite agent into the gap between the conductor strands, which actively inhibits the fatigue damage of the conductor, thereby prolonging the service life of the cable. The lubricating supplement microcapsule continuously releases lubricant under normal working stress of the cable, reducing the friction and wear between the strands, and reducing the initiation of microcracks from the source. Once microcracks occur, the crack repair microcapsule with a higher breaking threshold breaks under the stress concentration at the crack tip, releasing the repair agent to fill and adhere the crack, preventing further expansion.

[0020] 2. The preparation method proposed in the present application, particularly the protective twisting step, solves the technical problem of the destruction of functional microcapsules in the high-speed twisting process, ensuring the functional integrity of the active management composite agent in the final product. The shear thickening property of the carrier base fluid is used to form a high-viscosity gel state of the composite agent under high shear force applied during twisting, which buffers and fixes the microcapsules, protecting their structure from being destroyed.

[0021] 3. The present application builds a multi-level lubrication system covering the entire life cycle of the cable through the synergistic effect of multiple lubricating components. Among them, the perfluoropolyether as the carrier base fluid and the solid lubricant together constitute a stable and long-acting basic lubricating layer; and the progressive rupture of the lubricating supplement microcapsule serves as a supplementary lubrication mechanism, which can continuously supplement new low-viscosity lubricant during use. The multi-level lubrication system ensures that the conductor strands can maintain a low friction state both at the beginning and at the end of the cable's use, providing a sustained guarantee for inhibiting fatigue damage. DETAILED DESCRIPTION

[0022] The present application will be further described in detail below in combination with preparation examples, examples, comparative examples and test examples.

[0023] Unless otherwise specified, the raw materials and reagents used in the following examples are commercially available or can be prepared by known methods.

[0024] Preparation Example 1: The present preparation example provides a preparation method of the carrier base fluid, which includes the following steps: (1) In a 5L reaction kettle equipped with a mechanical stirrer, a heating jacket and a nitrogen inlet tube, 1000g of Y-type perfluoropolyether (main carrier base fluid, the kinematic viscosity measured at 25℃ is 500cSt) is added.

[0025] (2) Turn on mechanical stirring, set the speed to 150 rpm, and introduce nitrogen to replace the air in the reactor.

[0026] (3) Turn on the heating jacket and heat the main carrier base fluid in the reactor to 70°C.

[0027] (4) Under continuous stirring and nitrogen protection, slowly add 15 g of supramolecular polymer powder based on trimesamides (non-covalent crosslinking agent) through the feeding port.

[0028] (5) Maintain a temperature of 70°C and a stirring speed of 150 rpm for 1.5 hours until all the powder is completely dissolved and the liquid in the reactor becomes uniform and clear.

[0029] (6) Stop heating and naturally cool to room temperature under stirring to obtain the carrier base fluid, which is sealed for later use.

[0030] Preparation Example 2: The present preparation example provides a method for preparing lubricating supplementary microcapsules, comprising the following steps.

[0031] (1) In an A beaker, weigh 10 g of gelatin and dissolve it in 990 g of deionized water, heat to 55°C and stir until completely dissolved to form a gelatin solution with a mass fraction of 1.0 wt%. In a B beaker, weigh 10 g of gum arabic and dissolve it in 990 g of deionized water, stir until completely dissolved to form a gum arabic solution with a mass fraction of 1.0 wt%.

[0032] (2) Add 100 g of low-viscosity Y-type perfluoropolyether lubricating oil (core, kinematic viscosity of 100 mPa·s measured at 25°C) to the gelatin solution in the A beaker.

[0033] (3) Use a high-speed shearing emulsifier to shear and emulsify the above mixture at 55°C and a speed of 600 rpm for 20 minutes to form an O / W emulsion with uniformly dispersed oil droplets.

[0034] (4) Add the gum arabic solution prepared in step (1) to the emulsion of step (3). Slowly add a 10% mass fraction acetic acid solution using a dropper and monitor the pH value in real time until the pH value of the system stabilizes at 4.2. At this time, it is observed that coagulum is generated around the oil droplets.

[0035] (5) Transfer the reaction system to an ice water bath and quickly cool it to below 10°C.

[0036] (6) Based on a total mass of 20 g of wall material (gelatin and gum arabic), weigh 2.5 g of a 25% mass fraction glutaraldehyde aqueous solution (crosslinking agent) and slowly add it to the reaction system, which is continuously stirred at a low speed at 10°C for 4 hours of solidification reaction.

[0037] (7) After the reaction is completed, the product is suction filtered and washed with deionized water for 3-5 times, and then placed in a vacuum drying oven and dried at 40℃ for 12 hours to obtain the lubricating supplementary microcapsules in white powder form.

[0038] Preparation Example 3 The preparation example provides a preparation method of crack repair microcapsules, including the following steps.

[0039] (1) In a reaction kettle equipped with a high-speed stirring paddle, 500g of deionized water, 15g of urea, 20g of formaldehyde solution (mass fraction of 37wt%), 5g of polyurethane prepolymer and 1g of sodium dodecyl benzene sulfonate (emulsifier) are sequentially added, the stirring is started and the temperature is raised to 60℃.

[0040] (2) In another container, 100g of ethyl cyanoacrylate monomer (capsule core, containing 200ppm of hydroquinone as a stabilizer) is weighed.

[0041] (3) The ethyl cyanoacrylate monomer in step (2) is slowly added to the reaction kettle in step (1), and the stirring rate is increased to 1000rpm, and under this condition, the emulsion is emulsified for 30 minutes to form a stable O / W type emulsion.

[0042] (4) Slowly add triethanolamine using a dropper to adjust the pH value of the emulsion to 8.5 to initiate the polymerization reaction of urea and formaldehyde at the oil droplet interface.

[0043] (5) The reaction temperature is maintained at 60℃ and the pH value is maintained at 8.5, and the reaction is continued for 4 hours to allow the wall material to fully solidify.

[0044] (6) After the reaction is completed, the heating is stopped and the temperature is naturally cooled to room temperature. The product is centrifuged and washed with deionized water and ethanol alternately for several times, and finally freeze-dried for 24 hours to obtain the crack repair microcapsules in white powder form.

[0045] Example 1 The anti-fatigue fracture drag chain cable provided in the example includes a conductor composed of a plurality of twisted wires, an insulating layer wrapped outside the conductor, and an outer sheath wrapped on the outermost part.

[0046] The conductor is composed of 117 bare copper monofilaments with a diameter of 0.09mm, which meets the structure of the 6th conductor, and the nominal cross-sectional area is 0.75mm 2 In the gap between the plurality of wires, an active management composite agent is filled.

[0047] The active management composite agent is composed of the following components by weight: Carrier base fluid (prepared from Preparation Example 1): 100 parts; Lubrication supplementing microcapsules (prepared from Preparation Example 2): 8.0 parts; Crack repairing microcapsules (prepared from Preparation Example 3): 12.0 parts; Solid lubricant (hexagonal boron nitride powder, average particle size 1 μm): 2.0 parts.

[0048] The material of the insulation layer is thermoplastic polyurethane (TPU), and the material of the outer sheath is polyurethane (PUR).

[0049] The embodiment provides a method for preparing the aforementioned drag chain cable, and specific steps are as follows: S1, preparing a proactive management composite agent: 100 parts by weight of a carrier base fluid, 8.0 parts by weight of lubrication supplementing microcapsules, 12.0 parts by weight of crack repairing microcapsules and 2.0 parts by weight of hexagonal boron nitride powder are added into a planetary stirring mixer, and mixing is performed at an ambient temperature of 30 DEG C and a stirring speed of 80 rpm for 45 minutes until uniform dispersion.

[0050] S2, pretreating the plurality of wires: 19 single copper wires with a diameter of 0.18 mm are cleaned in an atmospheric pressure plasma cleaning device by using a mixed gas of argon and oxygen as working gas at a power of 400 W and a wire speed of 15 m / min.

[0051] S3, filling the proactive management composite agent by using a vacuum infiltration method: the cleaned plurality of wires are introduced into a vacuum infiltration cavity, the vacuum degree of the cavity is extracted to 30 Pa, the proactive management composite agent preheated to 50 DEG C is injected, the wires are completely immersed, and the infiltration is kept for 10 minutes.

[0052] S4, forming a conductor by protective stranding: the infiltrated plurality of wires are introduced into a linked online high-speed wire stranding machine, a stranding wire speed of 120 m / min and a stranding pitch of 9.5 mm (10 times of the outer diameter of the conductor after stranding) are set, and the conductor is formed.

[0053] S5, insulation, cabling and sheath extrusion: the conductor is subjected to insulation layer extrusion by using a wire and cable extruder, and the insulated wire core is formed. The temperature of each zone of the extruder is set as follows: the temperature of the cylinder zone one is 175 DEG C, the temperature of the cylinder zone two is 185 DEG C, the temperature of the cylinder zone three is 190 DEG C, and the temperature of the die is 195 DEG C. Then, 7 insulated wire cores are stranded into a cable by using a planetary cabling machine, and the cabling pitch is 7 times of the pitch circle diameter of the cable core. Finally, the cable core after cabling is subjected to outer sheath extrusion by using a pressure extrusion process, and the extrusion temperature ranges from 190 DEG C to 210 DEG C, so that the finished product is obtained.

[0054] Example 2: The anti-fatigue fracture drag chain cable provided by the embodiment comprises a conductor composed of a plurality of twisted wires, an insulation layer wrapped outside the conductor, and an outer sheath wrapped on the outermost part.

[0055] The conductor is composed of 117 bare copper monofilaments with a diameter of 0.09 mm, which meets the structure of the 6th conductor and has a nominal cross-sectional area of 0.75 mm 2 In the gap between the plurality of wires, an active management composite is filled.

[0056] The active management composite is composed of the following components by weight: Carrier base fluid (prepared by Preparation Example 1): 100 parts; Lubrication supplementing microcapsules (prepared by Preparation Example 2): 5.9 parts; Crack repair microcapsules (prepared by Preparation Example 3): 21.5 parts; Solid lubricant (nanoscale polytetrafluoroethylene powder, average particle size 500 nm): 4.3 parts.

[0057] The material of the insulation layer is thermoplastic polyurethane (TPU), and the material of the outer sheath is polyurethane (PUR).

[0058] The embodiment provides a method for preparing the aforementioned drag chain cable, and the specific steps are as follows: S1, preparing an active management composite: 100 parts by weight of a carrier base fluid, 5.9 parts by weight of lubrication supplementing microcapsules, 21.5 parts by weight of crack repair microcapsules, and 4.3 parts by weight of nanoscale polytetrafluoroethylene powder are added to a planetary stirring mixer, and mixed at an ambient temperature of 25°C and a stirring speed of 50 rpm for 60 minutes until uniformly dispersed.

[0059] S2, pretreating the plurality of wires: 19 single copper wires with a diameter of 0.22 mm are cleaned by an atmospheric pressure plasma cleaning device with a mixed gas of argon and oxygen as working gas at a power of 300 W and a wire speed of 20 m / min.

[0060] S3, filling the active management composite by vacuum infiltration: the cleaned plurality of wires are introduced into a vacuum infiltration cavity, and the vacuum degree of the cavity is extracted to 50 Pa. The active management composite preheated to 40°C is injected to completely immerse the wires, and the infiltration is maintained for 15 minutes.

[0061] S4, protective twisting to form a conductor: the infiltrated plurality of wires are introduced into a linked online high-speed wire bundling machine, and the twisting line speed is set to 80 m / min and the twisting pitch is set to 9.2 mm (8 times the outer diameter of the conductor after twisting) to form the conductor.

[0062] S5, insulation, cabling and sheath extrusion: the conductor is subjected to insulation layer extrusion by a wire and cable extruder to form an insulated core, and the extrusion temperature ranges from 170℃ to 180℃. Then, 7 insulated cores are twisted into a cable by a planetary cabling machine, and the cabling pitch is 6 times the diameter of the cable core pitch circle. Finally, the cable core after cabling is subjected to outer sheath extrusion by pressure extrusion process, and the extrusion temperature ranges from 180℃ to 200℃ to obtain the finished product.

[0063] Example 3: The anti-fatigue fracture drag chain cable provided in this embodiment has a structure comprising a conductor twisted from a plurality of wires, an insulation layer wrapped outside the conductor, and an outer sheath wrapped on the outermost part.

[0064] The conductor is twisted from 117 bare copper filaments with a diameter of 0.09mm, which meets the structure of the 6th conductor, and the nominal cross-sectional area is 0.75mm 2 In the gap between the plurality of wires, a proactive management composite agent is filled.

[0065] The proactive management composite agent is composed of the following components by weight: Carrier base fluid (prepared by Preparation Example 1): 100 parts; Lubrication supplementing microcapsules (prepared by Preparation Example 2): 14.3 parts; Crack repair microcapsules (prepared by Preparation Example 3): 5.9 parts; Solid lubricant (hexagonal boron nitride powder, average particle size 1μm): 1.2 parts.

[0066] The material of the insulation layer is thermoplastic polyurethane (TPU), and the material of the outer sheath is polyurethane (PUR).

[0067] The method for preparing the aforementioned drag chain cable is provided in this embodiment, and the specific steps are as follows: S1, preparation of proactive management composite agent: 100 parts by weight of carrier base fluid, 14.3 parts by weight of lubrication supplementing microcapsules, 5.9 parts by weight of crack repair microcapsules and 1.2 parts by weight of hexagonal boron nitride powder are added to a planetary stirring mixer, and mixed at an ambient temperature of 40℃ and a stirring speed of 100rpm for 30 minutes until uniformly dispersed.

[0068] S2, pretreatment of the plurality of wires: 19 single copper wires with a diameter of 0.15mm are subjected to online continuous cleaning by an atmospheric pressure plasma cleaning device using a mixture of argon and oxygen as working gas at a power of 500W and a wire speed of 10m / min.

[0069] S3, filling the active management composite by vacuum infiltration: the cleaned multi-strand wire is introduced into the vacuum infiltration cavity, and the vacuum degree of the cavity is extracted to 10 Pa. The preheated active management composite at 60°C is injected to completely immerse the wire, and the infiltration is maintained for 5 minutes.

[0070] S4, protective stranding to form a conductor: the infiltrated multi-strand wire is introduced into the online high-speed beam machine, the stranding line speed is set to 150 m / min, and the stranding pitch is 9.0 mm (12 times the outer diameter of the conductor after stranding), to form a conductor.

[0071] S5, insulation, cabling and sheath extrusion: the wire and cable extruder is used to extrude the insulation layer of the conductor to form an insulated wire core, and the extrusion temperature range is 210-220°C. Then, 7 insulated wire cores are stranded into a cable by a planetary cabling machine, and the cabling pitch is 8 times the pitch circle diameter of the cable core. Finally, the pressure extrusion process is used to extrude the outer sheath of the cabled cable core, and the extrusion temperature range is 200-220°C, to obtain the finished product.

[0072] Comparative Example 1: Compared with Example 1, the difference is that the active management composite is not prepared, and the multi-strand wire without vacuum infiltration is directly stranded when the conductor is prepared. The rest of the preparation conditions are the same.

[0073] Comparative Example 2: Compared with Example 1, the difference is that when preparing the active management composite, only 2 parts by weight of hexagonal boron nitride powder is added to 100 parts by weight of the carrier base fluid prepared in Preparation Example 1, without adding any microcapsule. The rest of the preparation conditions are the same.

[0074] Comparative Example 3: Compared with Example 1, the difference is that when preparing the active management composite, only 8 parts by weight of the lubrication supplementing microcapsule prepared in Preparation Example 2 and 2 parts by weight of hexagonal boron nitride powder are added to 100 parts by weight of the carrier base fluid, without adding the crack repairing microcapsule prepared in Preparation Example 3. The rest of the preparation conditions are the same.

[0075] Comparative Example 4: Compared with Example 1, the difference is that in the protective stranding step, a conventional low-speed stranding process is used, and the stranding line speed is set to 15 m / min, which is not enough to stimulate the shear thickening effect of the carrier base fluid. The rest of the preparation conditions are the same.

[0076] Test Example 1: Reference standard: this test refers to the relevant provisions of GB / T4909.4-2009 "Bare Wire Test Methods Part 4: Torsion Test".

[0077] The conductors in the cables prepared in Examples 1-3 and Comparative Examples 1-4 were selected for comparative testing.

[0078] Experimental procedure: Test sample preparation: To simulate high-end application scenarios, the finished cables of Examples 1-3 and Comparative Examples 1-4 used in this test all used a 6th class high-flexibility conductor structure for the internal conductor, with the specific specification being 117 / 0.09BC (consisting of 117 strands of bare copper wire with a diameter of 0.09 mm). From the above cable, the outer sheath and insulation layer were carefully stripped, and the conductor was completely removed. Three sections of conductor samples were cut, each with an effective test length (distance between the two clamps) of 100 times the outer diameter of the conductor after stranding.

[0079] Test equipment: A conductor torsion tester in accordance with GB / T 4909.4-2009 standard was used.

[0080] Installation and parameter setting: The conductor sample was installed vertically in the tester, with both ends clamped by the upper and lower clamps. A constant axial tension was applied to the lower end of the sample, which should keep the conductor sample straight without plastic elongation; the torsion angle was set to ±360° (i.e. one turn in one direction and one turn in the opposite direction), and the torsion speed was 30 times / minute.

[0081] Operation and monitoring: The tester was started, and the conductor sample was subjected to continuous reciprocating torsion cycles.

[0082] Failure determination: When the conductor sample broke due to metal fatigue, the tester automatically stopped.

[0083] Data recording: The cumulative number of torsions displayed by the tester when it automatically stopped was recorded. The three samples in each group were repeatedly tested, and the arithmetic mean was taken as the final torsion fatigue life. The test results are shown in Table 1.

[0084] Table 1 Test results of conductor torsion fatigue life Sample origin Torsional fatigue life (million cycles) Example 1 562.3 Example 2 551.8 Example 3 575.4 Comparative Example 1 83.7 Comparative Example 2 152.4 Comparative Example 3 281.9 Comparative Example 4 165.2 From Table 1, it can be seen that: The torsion fatigue life of the conductor samples of Examples 1, 2 and 3 was significantly higher than that of the conductor samples of Comparative Examples 1 to 4. This set of data gradually revealed the effect of each component of the composite agent and the specific preparation process on the performance of the conductor. The life of Comparative Example 1 (without composite agent) was the lowest, serving as a reference value. The life of Comparative Example 2 (containing only the base lubricant) increased compared to Comparative Example 1, due to the reduction of basic friction between the strands by the carrier base fluid and the solid lubricant. The life of Comparative Example 3 (increasing the lubricating microcapsules) further increased compared to Comparative Example 2, confirming the function of the lubricating supplementary microcapsules in continuously releasing lubricant under stress, effectively inhibiting wear and micro-crack initiation.

[0085] The service life of Examples 1, 2 and 3 is improved by the largest margin compared to Comparative Example 3, which is directly attributed to the presence of crack repair microcapsules. This component can fill and passivate the cracks by releasing repair agents after the formation of microcracks, thereby preventing their expansion into macroscopic fractures.

[0086] In addition, the service life of Comparative Example 4 (using a low-speed twisting process) is similar to that of Comparative Example 2, which is much lower than that of Example 1, indicating that the functional microcapsules have been damaged in large quantities during the preparation process at the low shear rate of the low-speed twisting process, resulting in the failure of their preset functions. This data confirms the necessity of using a high-speed twisting process and the shear thickening effect of the carrier base fluid to protect the integrity of the microcapsule structure.

[0087] Test Example 2: Reference Standard: GB / T2951.11-2008 "Cables and optical cables - Insulation and sheath materials - General test methods - Part 11: General test methods - Measurement of thickness and outer dimensions - Mechanical property tests".

[0088] This test selected Examples 1 and Comparative Example 1 for comparative testing.

[0089] Experimental Steps: Test Sample Preparation: Carefully peel off the outer sheath layer from the finished cable of Examples 1 and Comparative Example 1, and use a Type 1 dumbbell-shaped punch machine in accordance with the provisions of GB / T2951.11-2008 to cut at least 5 effective samples along the axial direction of the cable. Use a thickness gauge to measure the thickness and width of the test portion of the sample.

[0090] Test Equipment: An electronic tensile testing machine with an accuracy of not less than 1% is used, which is equipped with a device capable of automatically recording the tensile load and elongation.

[0091] Test Procedure: Clamp the ends of the dumbbell sample in the clamps of the tensile testing machine, set the tensile speed to 250±50 mm / min. Start the device to stretch the sample until it breaks.

[0092] Data Recording and Calculation: Record the maximum tensile force (load) and elongation distance between the marks when each sample breaks. Calculate the tensile strength (unit: MPa) and elongation at break (unit: %) of the material according to the formula, respectively.

[0093] Result Processing: After removing invalid data, calculate the median of the test results of the remaining effective samples as the final test result of the sample group. The test results are shown in Table 2.

[0094] Table 2 Mechanical Property Test Results of Outer Sheath Material Sample origin Tensile strength (MPa) Elongation at break (%) Example 1 18.2 465 Comparative Example 1 18.5 470 From Table 2, we can see that: The jacket materials of Example 1 and Comparative Example 1 are at the same level in the two key physical performance indicators of tensile strength and elongation at break, and there is no statistically significant difference.

[0095] Tensile strength reflects the maximum stress that the material can resist before being stretched to break, and elongation at break characterizes the toughness or ductility of the material. The test results show that the series of preparation steps adopted by the present application, including vacuum infiltration filling inside the conductor and subsequent insulation and jacket extrusion process parameters, do not cause measurable negative effects on the molecular structure or physical properties of the outer protective layer material. This confirms that the introduced internal complexing agent and related process have good compatibility with the standard cable jacket extrusion process.

[0096] Therefore, while achieving the performance improvement of the conductor core, the mechanical integrity of the cable outer jacket and the physical protection ability of the internal elements are maintained, ensuring that the overall structural performance of the finished cable meets the established standards.

[0097] Although embodiments of the present application have been shown and described, it is to be understood that various modifications, substitutions, replacements and changes can be made to these embodiments without departing from the principles and spirit of the present application, and the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A fatigue-resistant drag chain cable, characterized in that: The drag chain cable comprises: At least one conductor consisting of multiple strands of wire; an insulating layer wrapped around the conductor to form an insulated core; An outer sheath wrapped around the outside of the insulating core; an active management compound filled in gaps between the plurality of wire strands; The active management compound comprises the following components in parts by weight: Carrier base liquid: 100 parts; Lubricating supplement microcapsules: 5.9-14.3 parts; Crack repair microcapsules: 5.9-21.5 parts; Solid lubricant: 1.2-4.3 parts.

2. A fatigue-fracture-resistant drag chain cable according to claim 1, characterized in that: The carrier base liquid comprises a main carrier base liquid and a non-covalent bond cross-linking agent; the main carrier base liquid is perfluoropolyether, and the non-covalent bond cross-linking agent is a supramolecular polymer based on trimesic acid amide.

3. The fatigue-fracture-resistant drag chain cable according to claim 1, characterized in that: The lubricating supplement microcapsule comprises a capsule core and a wall material; the capsule core is low-viscosity lubricating oil, and the wall material is gelatin and gum arabic; the capsule core of the crack repair microcapsule is cyanoacrylate monomer, and the wall material is urea-formaldehyde resin modified polyurethane.

4. The fatigue-fracture-resistant drag chain cable according to claim 1, characterized in that: The solid lubricant is hexagonal boron nitride or nanometer-grade polytetrafluoroethylene powder.

5. The fatigue-fracture-resistant drag chain cable and preparation method according to claim 1, characterized in that: The drag chain cable may optionally include a central tensile element located at the center of the plurality of conductors.

6. A method for preparing a fatigue-resistant drag chain cable, characterized in that: The method for preparing a fatigue-fracture-resistant drag chain cable according to any one of claims 1 to 5 comprises the following steps: S1. Prepare active management compound; S2. Pre-processing the multi-strand wires; S3, filling the active management composite into the gaps between the multiple wires by vacuum infiltration; S4, protectively twisting the impregnated multiple wires to form a conductor; S5. Insulate and extrude the conductor to form an insulated core, and then cable and extrude an outer sheath on the insulated core.

7. The method for preparing a fatigue-fracture-resistant drag chain cable according to claim 6, characterized in that: In step S1, the preparation steps of the active management composite agent include: In a planetary mixer, lubrication replenishing microcapsules, crack repairing microcapsules and solid lubricant are added to the pre-prepared carrier base liquid; Mix at an ambient temperature of 25-40°C and a stirring rate of 50-100 rpm for 30-60 minutes until uniformly dispersed.

8. The method for preparing a fatigue-fracture-resistant drag chain cable according to claim 7, characterized in that: In step S2 and step S3, the steps of pre-treating the multi-strand wires and filling the gaps between the multi-strand wires with the active management composite agent respectively include: Using atmospheric pressure plasma cleaning equipment, using a mixture of argon and oxygen as the working gas, at a power of 300-500W, the multi-strand wire is continuously cleaned online at a line speed of 10-20m / min; The cleaned multi-strand wires are introduced into a vacuum infiltration chamber, the vacuum degree of the chamber is evacuated to 10-50 Pa, the active management composite agent preheated to 40-60° C. is injected, and the infiltration is maintained for 5-15 minutes.

9. The method for preparing a fatigue-fracture-resistant drag chain cable according to claim 8, characterized in that: In step S4, the step of forming a conductor includes: An online high-speed wire bundler linked to a vacuum infiltration system is used to introduce the infiltrated multi-strand conductors directly into the stranding die. The stranding speed is set at 80-150 m / min, and the stranding pitch is 8-12 times the outer diameter of the conductor after stranding. The combination of the linear speed and pitch exerts shear force on the active management composite, causing it to undergo reversible shear thickening, forming a temporary gel state to protect the microcapsules in the active management composite. After the twisting is completed, the shear force disappears and the active management composite returns to a fluid state.

10. The method for preparing a fatigue-fracture resistant drag chain cable according to claim 9, characterized in that: In step S5, the steps of forming an insulated core and cabling and extruding an outer sheath on the insulated core include: Using a wire and cable extruder, extruding the insulation layer of the conductor at a temperature range of 170-220° C. to form the insulated wire core; A planetary cabling machine is used to twist the plurality of insulated wire cores into a cable at a pitch of 6 to 8 times the pitch diameter of the cable core; The pressure extrusion process is used to extrude the outer sheath of the cable core after cabling in the temperature range of 180-220℃.