Anti-aging composite armored layer cross-linked polyethylene power cable and processing technology thereof

Abstract

This invention relates to the field of power cables, specifically to an anti-aging composite armored cross-linked polyethylene power cable and its processing technology. The anti-aging composite armored cross-linked polyethylene power cable includes several cores and, from the inside out, a sheath, an armor layer, and an outer sheath sequentially wrapped around the cores. The armor layer includes a first armor sheath and a second armor sheath with intermediate supports and fins. The first and second armor sheaths are symmetrically interlocked around the outer sheath. Each intermediate support has two openings facing away from the inner sheath, and each main loading groove contains a tensile steel cable. This invention, through structural optimization of the armor layer and the inclusion of tensile steel cables, enhances the tensile strength of the steel tape armor. This allows the armor layer to possess both the excellent mechanical protection properties of steel tape armor (such as puncture resistance) and the strong tensile strength of steel wire armor, thus enabling the power cable to adapt to applications requiring both mechanical protection and tensile strength.

Description

Technical Field

[0001] This invention relates to the field of power cable technology, specifically to an anti-aging composite armored cross-linked polyethylene power cable and its processing technology. Background Technology

[0002] Armored power cables are special cables with a metal sheath. Specifically, they use polyvinyl chloride (PVC) or cross-linked polyethylene (XLPE) as insulation material, with an outer layer of galvanized steel wire or steel tape as armor. Steel tape armored cables use steel tape spirally wrapped around the inner sheath to form the armor layer. They are characterized by good mechanical protection and compressive strength, making them suitable for most applications requiring resistance to external mechanical forces. Steel wire armored cables use thick or thin steel wire wrapped around the inner sheath to form the armor layer. They are characterized by good tensile strength and are suitable for applications requiring resistance to large tensile forces, such as vertical shafts and underwater installations. However, neither steel wire nor steel tape armored cables can meet the requirements for applications demanding both tensile strength and mechanical protection.

[0003] Meanwhile, during the laying process, power cables inevitably bend due to the laying trajectory. After the cable bends, compressive stress and tensile stress will appear in the insulation layer on both sides facing and away from the bending center, respectively. Mechanical stress will have an additional impact on the chemical bonds and cross-linking bonds of polymer molecules. Among them, tensile stress is more likely to be broken by the electric field, thereby generating electrical trees and accelerating their growth. As electrical trees continue to grow, the insulation material may age prematurely, the electrical strength will gradually decrease, the performance will gradually decline, and eventually insulation breakdown may occur, causing equipment failure or even power outage accidents.

[0004] The information disclosed in the background section of this invention is intended only to enhance the understanding of the general background of this invention, and should not be construed as an admission or in any way implying that such information constitutes prior art known to those skilled in the art. Summary of the Invention

[0005] In view of the shortcomings of the prior art, one object of the present invention is to propose an anti-aging composite armored cross-linked polyethylene power cable and its processing technology, so as to solve the problem of the limited application scope of existing armored power cables.

[0006] Another objective of this invention is to solve the problem that armored power cables are prone to aging and performance degradation after bending.

[0007] The present invention provides an anti-aging composite armored cross-linked polyethylene power cable with the following technical solution: comprising several cores and, from the inside out, a wrapping tape, an inner sheath, an armor layer, and an outer sheath that are sequentially wrapped around the outside of the cores, with a filler material provided between the wrapping tape and the cores; The armor layer includes a first armor sleeve and a second armor sleeve. The first armor sleeve and the second armor sleeve have the same structure and both include a middle keel and fins. Multiple sets of fins are evenly arranged along the extension direction of the middle keel, with two fins in each set. The two fins in each set are symmetrically arranged on both sides of the middle keel. Two first slots are provided on the outer periphery of the inner sheath, which are located on both sides of the same diameter direction of the inner sheath. The intermediate keels of the first armor sheath and the second armor sheath are respectively embedded in the two first slots. Two openings opposite to the main loading groove of the inner sheath are formed on each intermediate keel. A limiting plate is provided at the end of the fin. The fins of the first armor sheath and the second armor sheath are alternately wrapped around the inner sheath along the axial direction of the inner sheath. The limiting plate of the fin of the first armor sheath is embedded in the main loading groove of the intermediate keel of the second armor sheath, and the limiting plate of the fin of the second armor sheath is embedded in the main loading groove of the intermediate keel of the first armor sheath. Each main loading slot is fitted with a tensile steel cable, which is pressed against the limiting pressure plate.

[0008] Optionally, the fins are trapezoidal, with the larger end connected to the middle keel.

[0009] Optionally, the opening of the main loading slot is narrowed.

[0010] Optionally, each fin is further provided with at least one auxiliary locking protrusion, and the outer periphery of the inner sheath is provided with a second locking groove corresponding to the auxiliary locking protrusion. The auxiliary locking protrusion is embedded in the second locking groove, and an auxiliary loading groove with an opening opposite to the inner sheath is formed on the auxiliary locking protrusion. A tensile steel cable is embedded in the auxiliary loading groove.

[0011] Optionally, the opening of the auxiliary loading slot is narrowed.

[0012] Optionally, the two sides of the first slot are inclined surfaces, and the distance between the two inclined surfaces of the first slot gradually increases from the axis closer to the inner sheath to the axis farther away from the inner sheath; a metal support plate is fixed inside the first slot, and the shape of the metal support plate is adapted to the shape of the first slot. A connecting slot with an opening facing the inner sheath is formed between the two main loading slots of the middle keel. An elastic rubber strip is provided in the first slot. The elastic rubber strip is located between the middle keel and the metal support plate. The side of the elastic rubber strip near the middle keel is adapted to the shape of the middle keel, and the side of the elastic rubber strip near the metal support plate is adapted to the shape of the metal support plate. When a power cable is bent, its bending direction is configured such that the intermediate keel of the first armored sheath and the second armored sheath are located on the inner arc side and the outer arc side of the power cable, respectively.

[0013] Optionally, the outer periphery of the outer sheath is marked with a line corresponding to the position of the middle keel.

[0014] Optionally, the conductor includes a conductor and a conductor shielding layer, an insulation layer, an insulation shielding layer, and a copper tape shielding layer that wrap around the outside of the conductor from the inside out.

[0015] A processing technology for producing cross-linked polyethylene power cables with anti-aging composite armor layers, specifically including the following steps: Step 1, process the wire core; Step 2: Arrange several wire cores as required and wrap them with a wrapping tape. Fill the space between the wrapping tape and the wire cores with filler material. Step 3: Wrap the inner sheath around the bag strap using an extrusion or burning process; Step 4: Wrap the inner sheath with an armor layer; Step 5: Install tensile steel cables in the main loading slot and auxiliary loading slot; Step 6: Wrap the outer sheath around the armor layer and the tensile steel cable.

[0016] Optionally, step 4 includes: Step 4.1: Bend and punch the steel strip to process it into the first armor sleeve and the second armor sleeve; Step 4.2: The first armor sleeve and the second armor sleeve are symmetrically arranged on both sides of the inner sleeve in the same diameter direction; Step 4.3: Bend the fins and wrap them around the inner sheath.

[0017] The beneficial effects of this invention are as follows: The anti-aging composite armored cross-linked polyethylene power cable of this invention sets the armor layer as a symmetrically interlocking wrapping of a first armor sheath and a second armor sheath, and forms a through-type intermediate keel on the first and second armor sheaths, which improves the tensile strength of the steel tape armor. By embedding tensile steel cables on the first and second armor sheaths, the tensile strength of the armor layer is further improved, so that the armor layer has both the good mechanical protection performance such as puncture resistance of steel tape armor and the strong tensile strength of steel wire armor, making the power cable suitable for occasions that require both mechanical protection and tensile strength, taking into account both economy and performance.

[0018] Furthermore, by setting up metal support plates and elastic rubber strips, after the power cable is bent, the middle keel on the side away from the bending center pulls the fins connected to it to move towards the first slot located on the outer arc side, transferring the tensile stress on the side away from the bending center to the side closer to the bending center, relieving the tensile stress on the power cable, preventing the chemical bonds and cross-linking bonds of the insulating polymer from being broken and destroyed by the electric field, reducing the probability of electrical tree generation, avoiding premature aging and failure of the power cable, and extending the performance and service life of the power cable. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a partial structural diagram of an anti-aging composite armored cross-linked polyethylene power cable according to the present invention. Figure One (The armor layer is in the deployed state); Figure 2 This is a partial structural diagram of an anti-aging composite armored cross-linked polyethylene power cable according to the present invention. Figure Two (The armor layer is in a bent state); Figure 3 This is a partial structural diagram of an anti-aging composite armored cross-linked polyethylene power cable according to the present invention. Figure Three (The armor layer is in a wrapped state); Figure 4 for Figure 3 The front view; Figure 5 This is a partial structural diagram of an anti-aging composite armored cross-linked polyethylene power cable according to the present invention. Figure Four (Tensile steel cable assembly completed); Figure 6 for Figure 5 The front view; Figure 7 for Figure 6 Enlarged view of point A in the middle; Figure 8 for Figure 6 Enlarged view at point B in the middle; Figure 9 This is a schematic diagram of the overall structure of an anti-aging composite armored cross-linked polyethylene power cable according to the present invention. Figure One (The power cable is in a straight position); Figure 10 This is a schematic diagram of the overall structure of an anti-aging composite armored cross-linked polyethylene power cable according to the present invention. Figure Two (The power cable is bent.) Figure 11 for Figure 10 Side view; Figure 12 for Figure 11 CC section view; Figure 13 for Figure 11 DD section view; Figure 14 for Figure 13 Enlarged view at point E in the middle; Figure 15 for Figure 13 Enlarged view of point F in the middle.

[0021] In the picture: 100. Core wire; 101. Conductor wire; 102. Conductor shielding layer; 103. Insulation layer; 104. Insulation shielding layer; 105. Copper tape shielding layer; 200. Bag strap; 300. Inner sheath; 301. First slot; 302. Second slot; 400, Armor layer; 410, First armor sleeve; 411, Intermediate keel; 4111, Main loading slot; 4112, Connecting slot; 412, Fin; 4121, Limiting pressure plate; 4122, Auxiliary loading slot; 420, Second armor sleeve; 500, outer sheath; 600. Filler material; 700, tensile steel cable; 800. Metal support plate; 900, Elastic rubber strip. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] like Figures 1 to 15As shown in the figure, the anti-aging composite armored cross-linked polyethylene power cable provided by the present invention includes several cores 100, and a wrapping tape 200, an inner sheath 300, an armor layer 400 and an outer sheath 500 wrapped around the cores 100 from the inside to the outside. The insulation structure of the cores 100 can be made of cross-linked polyethylene (XLPE or PEX). Cross-linked polyethylene is formed by introducing cross-linking bonds between polyethylene molecular chains through chemical or physical methods (such as peroxide cross-linking, silane cross-linking, radiation cross-linking) to form a three-dimensional network structure, thereby transforming it from a thermoplastic material into a thermosetting material, which greatly improves the material's heat resistance, mechanical properties and chemical corrosion resistance, while also providing excellent electrical insulation properties and a longer lifespan, thus improving the performance and lifespan of the power cable. A filler material 600 is provided between the wrapping tape 200 and the conductor 100; the filler material 600 can fill the gaps between the conductors 100, keep the cable round and improve structural stability; the wrapping tape 200 is used to bundle the conductors 100 to prevent loosening; the inner sheath 300 can be made of polyvinyl chloride (PVC), polyethylene (PE), cross-linked polyethylene or low smoke halogen-free material, used to protect the conductors 100, and at the same time, it acts as a buffer layer during the armoring process to prevent the armor from damaging the internal structure; the armor layer 400 is the key protective layer of the power cable, which can provide mechanical protection as well as compression and tensile protection for the power cable; the outer sheath 500 can be made of polyvinyl chloride (PVC), polyethylene (PE), cross-linked polyethylene, etc., and flame retardants can be added, used for the outermost protection of the power cable, moisture-proof, corrosion-proof, UV-proof, weather-resistant, and protects the armor layer 400 from environmental erosion.

[0024] The armor layer 400 includes a first armor sleeve 410 and a second armor sleeve 420. The first armor sleeve 410 and the second armor sleeve 420 have the same structure and both include a central keel 411 and fins 412. Multiple sets of fins 412 are evenly arranged along the extension direction of the central keel 411, with two fins in each set. The two fins 412 in each set are symmetrically arranged on both sides of the central keel 411. The first armor sleeve 410 and the second armor sleeve 420 can be made by bending and punching steel strips. The inner sheath 300 has two first slots 301 on its outer periphery, located on opposite sides of the inner sheath 300 along the same diameter. The intermediate keels 411 of the first armor sheath 410 and the second armor sheath 420 are respectively fitted into the two first slots 301. Each intermediate keel 411 has two openings facing away from the inner sheath 300, forming a main loading groove 4111. A limit plate 4 is provided at the end of the fin 412 (i.e., the end away from the intermediate keel 411). 121, the fins 412 of the first armor sleeve 410 and the second armor sleeve 420 are alternately wrapped around the inner sleeve 300 along the axial direction of the inner sleeve 300, and the limiting pressure plate 4121 of the fins 412 of the first armor sleeve 410 is embedded in the main loading groove 4111 of the middle keel 411 of the second armor sleeve 420, and the limiting pressure plate 4121 of the fins 412 of the second armor sleeve 420 is embedded in the main loading groove 4111 of the middle keel 411 of the first armor sleeve 410; Each main loading slot 4111 is fitted with a tensile steel cable 700, which is pressed against the limiting pressure plate 4121.

[0025] It should be noted that existing armor layers 400 are generally divided into steel strip armor and steel wire armor. Steel strip armor involves spirally wrapping steel strips around the outside of the inner sheath 300, which has strong compressive strength and mechanical protection, but weak tensile strength, and is suitable for direct burial or tunnel laying. Steel wire armor uses thick or thin steel wires wrapped around the outside of the inner sheath 300, which has outstanding tensile strength, but weak mechanical protection, and is suitable for laying in vertical shafts, underwater, high-altitude and other working conditions. However, in situations where both tensile strength and mechanical protection are required (such as construction sites on slopes, semi-elevated large workshops, etc.), neither steel wire armor nor steel strip armor can meet the requirements.

[0026] In this embodiment, the armor layer 400 is configured as a symmetrical interlocking wrapping of a first armor sleeve 410 and a second armor sleeve 420, with a through-type intermediate keel 411 formed on the first armor sleeve 410 and the second armor sleeve 420. Compared with traditional steel strip armor, the present invention not only has the strong compressive strength and mechanical protection of steel strip armor, but also greatly improves the tensile strength of steel strip armor. Furthermore, by embedding tensile steel cables 700 in the intermediate keel 411, the tensile strength of the armor is further improved. The solution in this embodiment improves the tensile strength of the steel tape armor by optimizing the structure of the armor layer 400. By embedding tensile steel cables 700 on the first armor sheath 410 and the second armor sheath 420, the tensile strength of the armor layer 400 is further improved. This allows the armor layer 400 to have both the good mechanical protection performance of steel tape armor (such as puncture resistance) and the strong tensile strength of steel wire armor. As a result, the power cable can adapt to occasions that require both mechanical protection and tensile strength, taking into account both economy and performance.

[0027] In a further embodiment, the fin 412 is trapezoidal, and the large end is connected to the middle keel 411.

[0028] In this embodiment, by setting the shape of the fin 412 to trapezoidal, the fins 412 of the first armor sleeve 410 and the second armor sleeve 420 can be wrapped around the outer side of the inner sleeve 300 in a wedge-shaped insertion form, which is convenient for insertion. At the same time, the large end of the fin 412 is connected to the middle keel 411, which can improve the connection strength between the fin 412 and the middle keel 411, making the overall strength of the first armor sleeve 410 and the second armor sleeve 420 higher, thereby significantly improving the tensile strength of the armor layer 400.

[0029] In a further embodiment, each fin 412 is also provided with at least one auxiliary locking protrusion, and the outer periphery of the inner sheath 300 is provided with a second locking groove 302 corresponding to the auxiliary locking protrusion. The auxiliary locking protrusion is embedded in the second locking groove 302, and an auxiliary loading groove 4122 with an opening opposite to the inner sheath 300 is formed on the auxiliary locking protrusion. The tensile steel cable 700 is embedded in the auxiliary loading groove 4122.

[0030] In this embodiment, the engagement of the auxiliary protrusion and the second slot 302 further improves the stability and reliability of the armor layer 400 relative to the inner sheath 300. At the same time, by setting an auxiliary loading groove 4122 on the auxiliary protrusion and embedding a tensile steel cable 700 in the auxiliary loading groove 4122, the tensile strength of the armor layer 400 is further improved.

[0031] In a preferred embodiment of the present invention, an auxiliary locking protrusion is provided on the fin 412, and the auxiliary locking protrusion is located in the middle position of the fin 412; in other embodiments, multiple auxiliary locking protrusions may be provided on the fin 412, and the multiple auxiliary locking protrusions are evenly spaced in the length direction of the fin 412.

[0032] In a further embodiment, the opening of the main loading slot 4111 is narrowed, and the opening of the auxiliary loading slot 4122 is narrowed. Specifically, the main loading slot 4111 and the auxiliary loading slot 4122 can be set as C-shaped slots or other types, which can prevent the tensile steel cable 700 from coming out of the main loading slot 4111 or the auxiliary loading slot 4122 and ensure the installation reliability of the tensile steel cable 700.

[0033] In a further embodiment, the two sides of the first slot 301 are inclined surfaces, and the distance between the two inclined surfaces of the first slot 301 gradually increases from the axis closer to the inner sheath 300 to the axis farther away from the inner sheath 300; a metal support plate 800 is fixed inside the first slot 301, and the shape of the metal support plate 800 is adapted to the shape of the first slot 301; the metal support plate 800 is a thin plate, which has a certain support capacity and a certain micro-deformation capacity, and does not affect the bending of the power cable; A connecting slot 4112 with an opening facing the inner sheath 300 is formed between the two main loading slots 4111 of the intermediate keel 411. An elastic rubber strip 900 is provided in the first slot 301. The elastic rubber strip 900 is located between the intermediate keel 411 and the metal support plate 800. The side of the elastic rubber strip 900 near the intermediate keel 411 is adapted to the shape of the intermediate keel 411, and the side of the elastic rubber strip 900 near the metal support plate 800 is adapted to the shape of the metal support plate 800 to fill the space between the intermediate keel 411 and the metal support plate 800. When the power cable is bent, its bending direction is configured such that the intermediate keel 411 of the first armor sheath 410 and the second armor sheath 420 are located on the inner arc side and the outer arc side of the power cable, respectively.

[0034] Furthermore, the spacing between two adjacent fins 412 on the first armor sheath 410 and the spacing between two adjacent fins 412 on the second armor sheath 420 are slightly larger than the size of the fins 412, which facilitates the insertion of the first armor sheath 410 and the second armor sheath 420 into each other, and ensures that after the first armor sheath 410 and the second armor sheath 420 are assembled, there is a small gap between adjacent fins 412, which is beneficial for cable bending.

[0035] It is understandable that during the laying of power cables, straight sections and curved sections are inevitable due to the influence of the laying trajectory. After the power cable is bent, compressive stress is generated on the side closer to the center of the bend (inner arc side), and tensile stress is generated on the side farther from the center of the bend (outer arc side). Mechanical stress will have an additional impact on the chemical bonds and cross-linking bonds of the polymer molecules in the cable insulation structure. Among them, tensile stress is more likely to be broken by the electric field, which will generate electrical trees and accelerate their growth. Electrical trees (commonly known as electrical trees) are dendritic defects formed in the insulation structure of cross-linked polyethylene cables due to partial discharge. The formation and development of electrical trees will pose a serious threat to the insulation performance of power equipment. As electrical trees continue to grow, the electrical strength of the insulation structure gradually decreases, the performance ages prematurely, and may eventually lead to insulation breakdown, causing equipment failure or even power outage accidents.

[0036] In this embodiment, after the power cable is bent, the middle keel 411 on the side away from the bending center is squeezed by the tensile steel cable 700, and then, guided by the inclined surface of the metal support plate 800, it squeezes the elastic rubber strip 900 and moves it towards the bottom of the first slot 301. Figure 14 In the middle, from the perspective of the drawing, moving downwards), the middle keel 411 on the side near the center of the bend is squeezed by the tensile steel cable 700, and then moves towards the bottom of the first slot 301 under the guidance of the inclined surface of the metal support plate 800. Figure 15 In the middle, from the perspective of the drawing, moving upwards). Because when the power cable bends, the power cable on the tensile stress side is in a taut state and the power cable on the compressive stress side is in a relaxed state, the amount of movement of the intermediate keel 411 on the side away from the bending center is greater than the amount of movement of the intermediate keel 411 on the side closer to the bending center. Ultimately, this causes the intermediate keel 411 on the side away from the bending center to pull the fin 412 connected to it to move towards the first slot 301 located on the outer arc side. Figure 14 From an upward perspective, the tensile stress on the side away from the bending center is transferred to the side closer to the bending center, relieving the tensile stress on the power cable, preventing the chemical bonds and cross-linking bonds of the polymer molecules in the insulation structure from being broken or destroyed, reducing the probability of electrical treeing, avoiding premature aging and failure of the power cable, and extending the service life of the power cable; at the same time, when the middle keel 411 on the side away from the bending center pulls the fin 412 connected to it to move, the tensile steel cable 700 embedded in the auxiliary loading groove 4122 pulls the fin 412 on the side closer to the bending center, so that the middle keel 411 on the side closer to the bending center eventually moves away from the bottom of the corresponding first slot 301, thereby relieving the compressive stress on the power cable to a certain extent and further extending the service life of the power cable.

[0037] Furthermore, to improve the ease and reliability of installing the metal support plate 800 and the elastic rubber strip 900, limiting shoulders are provided on the top of both sides of the first slot 301. Both sides of the metal support plate 800 and both sides of the elastic rubber strip 900 have outward-turned edges. The outward-turned edges of the metal support plate 800 are pressed against the limiting shoulders, and the outward-turned edges of the elastic rubber strip 900 are pressed against the outward-turned edges of the metal support plate 800.

[0038] Furthermore, to ensure the reliability of the movement of the intermediate keel 411, the outer edge of the elastic rubber strip 900 can be pressed onto the outer edge of the metal support plate 800 and fixedly connected, and the part of the elastic rubber strip 900 that is adapted to the connecting groove 4112 can be fixedly connected to the connecting groove 4112. The specific fixing method can be adhesive bonding or other methods.

[0039] In a further embodiment, the outer periphery of the outer sheath 500 is provided with a marking line at the position corresponding to the intermediate keel 411.

[0040] In this embodiment, the position of the intermediate keel 411 can be accurately identified by setting the marking lines. When laying the power cable, the cable is bent according to the position of the marking lines to ensure that the intermediate keel 411 of the first armor sheath 410 and the second armor sheath 420 are located on the inner arc side and the outer arc side, respectively. This allows the armor layer 400 to transfer stress, alleviate the tensile and compressive stresses on the power cable, and extend the service life of the power cable.

[0041] In a further embodiment, the wire core 100 includes a conductor 101 and a conductor shielding layer 102, an insulation layer 103, an insulation shielding layer 104, and a copper strip shielding layer 105 wrapped around the outside of the conductor 101 from the inside to the outside. Conductor 101 is the core functional component of power cable, which plays the role of transmitting electrical energy and signals. Conductor 101 can be made of materials such as copper, aluminum, copper alloy or aluminum alloy. Copper conductor 101 has excellent conductivity and is widely used; aluminum conductor 101 is low in cost and light in weight, and is suitable for laying long spans.

[0042] The conductor shielding layer 102 is used to uniformly distribute the electric field on the conductor surface, preventing electric field concentration caused by uneven surface of the conductor 101 or strand gaps, thus avoiding partial discharge; it also prevents air gaps between the conductor 101 and the insulation layer 103, improving the cable's withstand voltage performance and service life; and it buffers the thermal shock to the insulation layer 103 caused by a sudden increase in conductor temperature during short circuits or overloads. The conductor shielding layer 102 is made of cross-linked or non-cross-linked semi-conductive materials, typically conductive carbon black mixed with polyethylene or cross-linked polyethylene, using extrusion or sintering processes. This invention preferably uses cross-linked polyethylene mixed with conductive carbon black.

[0043] Insulation layer 103 is the core electrical isolation layer of the power cable, used to prevent current leakage, short circuits, and electric shock accidents; it withstands the system's rated voltage and instantaneous overvoltage, ensuring long-term operation without breakdown; and it maintains stable electrical performance in harsh environments such as high temperature and chemical corrosion. Insulation layer 103 is made of cross-linked polyethylene, which has a heat resistance of over 90℃ and high insulation resistance, making it a mainstream material for medium and high voltage cables.

[0044] The insulating shielding layer 104 is used to uniformly shape the electric field on the outer surface of the insulating layer 103, prevent electric field distortion from damaging the outer sheath or causing partial discharge, and protect the insulating layer 103 from mechanical damage during installation and operation. The insulating shielding layer 104 is usually formed simultaneously with the insulating layer 103 and the conductor shielding layer 102 through a "three-layer co-extrusion" process to ensure a tight and smooth interface, reduce the risk of air gaps, and optimize the electric field distribution of the high-voltage cable. The insulating shielding layer 104 also uses a semi-conductive material, such as a cross-linked or non-cross-linked semi-conductive material. In this invention, a cross-linked polyethylene base material mixed with conductive carbon black is preferred.

[0045] The copper strip shielding layer 105 is made of copper strip or copper wire braid, which has good conductivity. It is mainly used to block the intrusion of external electromagnetic interference, prevent the electromagnetic field of the power cable itself from interfering with surrounding equipment, and ensure the quality of signal transmission. After the copper strip shielding layer 105 is connected to the grounding system, it can eliminate the potential difference between equipment and improve safety.

[0046] This invention also provides a processing method for an anti-aging composite armor layer cross-linked polyethylene power cable, used to process the aforementioned anti-aging composite armor layer cross-linked polyethylene power cable, specifically including the following steps: Step 1, process the wire core 100; Step 1.1: Select high-purity oxygen-free copper rods or aluminum rods, and make them into flexible wires 101 that meet the specifications through wire drawing, annealing and stranding. It should be noted that some large-specification wires 101 need to be compressed to improve conductivity and structural stability. Step 1.2: Using specialized extrusion equipment, the conductor shielding layer 102, the insulation layer 103, and the insulation shielding layer 104 are extruded simultaneously to form a tight "sandwich" structure. Then, through a cross-linking process (chemical cross-linking is the most widely used, using peroxide as a cross-linking agent to complete the reaction under high temperature and high pressure), the polyethylene molecular structure is cross-linked, which greatly improves the heat resistance and electrical performance of the insulation structure. The cross-linked insulation structure can withstand long-term high temperature tests of 90℃ and 250℃ during short circuits. Step 1.3: Braid a copper strip shielding layer 105 outside the insulating shielding layer 104; Step 2: Arrange several wire cores 100 as required and wrap them with a wrapping tape 200. Fill the space between the wrapping tape 200 and the wire cores 100 with filler material 600 to keep the power cable in a round shape. Step 3: Wrap the inner sheath 300 around the outer layer of the strap 200 using an extrusion or burning process; Step 4: Wrap the inner sheath 300 with the outer armor layer 400; Step 4.1: Bend and punch the steel strip to process it into the first armor sleeve 410 and the second armor sleeve 420; Step 4.2: The first armor sleeve 410 and the second armor sleeve 420 are symmetrically arranged on both sides of the inner sleeve 300 in the same diameter direction; Step 4.3: Bend the fin 412 and wrap it around the inner sheath 300; Step 5: Embed tensile steel cables 700 into the main loading slot 4111 and the auxiliary loading slot 4122; Step 6: Wrap the outer sheath 500 around the armor layer 400 and the tensile steel cable 700.

[0047] It should also be noted that in the embodiment where the metal support plate 800 and the elastic rubber strip 900 are provided, step 3 above further includes installing the metal support plate 800 and the elastic rubber strip 900 in the first slot 301 of the inner sheath 300.

[0048] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A cross-linked polyethylene power cable with an anti-aging composite armor layer, characterized in that, It includes several wire cores and, from the inside out, a wrapping tape, an inner sheath, an armor layer, and an outer sheath that are wrapped around the outside of the wire cores. Filler material is provided between the wrapping tape and the wire cores. The armor layer includes a first armor sleeve and a second armor sleeve. The first armor sleeve and the second armor sleeve have the same structure and both include a middle keel and fins. Multiple sets of fins are evenly arranged along the extension direction of the middle keel, with two fins in each set. The two fins in each set are symmetrically arranged on both sides of the middle keel. Two first slots are provided on the outer periphery of the inner sheath, which are located on both sides of the same diameter direction of the inner sheath. The intermediate keels of the first armor sheath and the second armor sheath are respectively embedded in the two first slots. Two openings opposite to the main loading groove of the inner sheath are formed on each intermediate keel. A limiting plate is provided at the end of the fin. The fins of the first armor sheath and the second armor sheath are alternately wrapped around the inner sheath along the axial direction of the inner sheath. The limiting plate of the fin of the first armor sheath is embedded in the main loading groove of the intermediate keel of the second armor sheath, and the limiting plate of the fin of the second armor sheath is embedded in the main loading groove of the intermediate keel of the first armor sheath. Each main loading slot is fitted with a tensile steel cable, which is pressed against the limiting pressure plate.

2. The anti-aging composite armored cross-linked polyethylene power cable according to claim 1, characterized in that, The fins are trapezoidal, with the larger end connected to the middle keel.

3. The anti-aging composite armored cross-linked polyethylene power cable according to claim 1, characterized in that, The opening of the main loading slot is narrowed.

4. The anti-aging composite armored cross-linked polyethylene power cable according to claim 1, characterized in that, Each fin is also provided with at least one auxiliary locking protrusion, and the outer periphery of the inner sheath is provided with a second locking groove corresponding to the auxiliary locking protrusion. The auxiliary locking protrusion is embedded in the second locking groove, and an auxiliary loading groove with an opening opposite to the inner sheath is formed on the auxiliary locking protrusion. A tensile steel cable is embedded in the auxiliary loading groove.

5. The anti-aging composite armored cross-linked polyethylene power cable according to claim 4, characterized in that, The opening of the auxiliary loading slot is narrowed.

6. The anti-aging composite armored cross-linked polyethylene power cable according to claim 4, characterized in that, The two sides of the first slot are inclined, and the distance between the two inclined surfaces of the first slot gradually increases from the axis closer to the inner sheath to the axis farther away from the inner sheath; a metal support plate is fixed inside the first slot, and the shape of the metal support plate is adapted to the shape of the first slot. A connecting slot with an opening facing the inner sheath is formed between the two main loading slots of the middle keel. An elastic rubber strip is provided in the first slot. The elastic rubber strip is located between the middle keel and the metal support plate. The side of the elastic rubber strip near the middle keel is adapted to the shape of the middle keel, and the side of the elastic rubber strip near the metal support plate is adapted to the shape of the metal support plate. When a power cable is bent, its bending direction is configured such that the intermediate keel of the first armored sheath and the second armored sheath are located on the inner arc side and the outer arc side of the power cable, respectively.

7. The anti-aging composite armored cross-linked polyethylene power cable according to claim 6, characterized in that, The outer sheath has marking lines on the periphery corresponding to the middle keel.

8. The anti-aging composite armored cross-linked polyethylene power cable according to claim 1, characterized in that, The conductor core includes the conductor and, from the inside out, the conductor shielding layer, the insulation layer, the insulation shielding layer, and the copper tape shielding layer that wrap around the outside of the conductor.

9. A processing technology for an anti-aging composite armor layer cross-linked polyethylene power cable, characterized in that, The method for producing the anti-aging composite armored cross-linked polyethylene power cable according to any one of claims 1-8 specifically includes the following steps: Step 1, process the wire core; Step 2: Arrange several wire cores as required and wrap them with a wrapping tape. Fill the space between the wrapping tape and the wire cores with filler material. Step 3: Wrap the inner sheath around the bag strap using an extrusion or burning process; Step 4: Wrap the inner sheath with an armor layer; Step 5: Install tensile steel cables in the main loading slot and auxiliary loading slot; Step 6: Wrap the outer sheath around the armor layer and the tensile steel cable.

10. The processing technology of an anti-aging composite armored cross-linked polyethylene power cable according to claim 9, characterized in that, Step 4 includes: Step 4.1: Bend and punch the steel strip to process it into the first armor sleeve and the second armor sleeve; Step 4.2: The first armor sleeve and the second armor sleeve are symmetrically arranged on both sides of the inner sleeve in the same diameter direction; Step 4.3: Bend the fins and wrap them around the inner sheath.

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