A high toughness power cable and a method of making the same

Abstract

This invention belongs to the field of cable technology, specifically a high-toughness power cable and its preparation method. The cable body includes a conductor wire, an insulation layer, a buffer interlayer, and a composite protective layer. The composite protective layer includes an inner sheath layer, an armor layer, and an outer sheath layer. The inner sheath layer is fitted onto the buffer interlayer. Multiple fine conductor wires are stranded using a standard stranding method with a stranding pitch of 10-15 times the conductor diameter. During stranding, the tension is controlled to be uniform, avoiding wire breakage and loose strands, thus preparing a flexible multi-strand stranded conductor, improving the conductor's toughness. The buffer interlayer is a flexible buffer interlayer made of polyurethane or nitrile rubber, with a thickness controlled between 0.5-1.2 mm. During laying, it ensures no wrinkles or gaps between layers and is fixed to the insulation layer by hot-pressing, absorbing external impact and bending stress, further improving the cable's toughness.

Description

Technical Field

[0001] This invention belongs to the field of cable technology, specifically a high-toughness power cable and its preparation method. Background Technology

[0002] As the "blood vessels" of modern power systems, power cables undertake the crucial task of power transmission and distribution, and are widely used in various scenarios such as urban power grids, industrial plants, and submarine power transmission. Their typical structure consists of a conductor, an insulation layer, a shielding layer, and a protective layer. The conductor is mostly made of copper or aluminum, and the insulation layer is mainly made of cross-linked polyethylene (XLPE) and polyvinyl chloride (PVC). Depending on the voltage level and application, they can be divided into high-voltage, medium-voltage, low-voltage cables, and control cables, meeting the power transmission needs of different scenarios.

[0003] Existing power cables have poor toughness in their insulation and protective layer materials, especially PVC, ordinary XLPE, and unmodified polypropylene. They are prone to hardening and cracking at low temperatures, and breakage occurs easily when they are bent or moved. During long-term use, material aging will further reduce toughness, leading to a decrease in tensile strength and elongation at break, which can easily cause faults such as insulation tearing and sheath damage, and even safety hazards such as leakage and power outage. Therefore, this invention provides a high-toughness power cable and its preparation method. Summary of the Invention

[0004] In order to overcome the shortcomings of the prior art, at least one technical problem raised in the background art is solved.

[0005] The technical solution adopted by this invention to solve its technical problem is as follows: A high-toughness power cable according to this invention includes a cable body, the cable body including a guide wire, an insulation layer, a buffer interlayer, and a composite protective layer; the composite protective layer includes an inner sheath layer, an armor layer, and an outer sheath layer; the inner sheath layer is sleeved on the buffer interlayer, the armor layer is an aluminum alloy strip, and is spirally wound on the inner sheath layer at a winding angle of 30-45°; both the inner sheath layer and the outer sheath layer are made of polyolefin material, a protective sleeve is provided on the outer sheath layer, and a drive wheel is rotatably connected to the outer side wall of the protective sleeve.

[0006] Preferably, a pair of symmetrically arranged support frames are fixedly connected to the outer wall of the protective sleeve, an arc-shaped connecting piece is fixedly connected to the bottom end of the support frame, and a support wheel is rotatably connected to the inner wall of the connecting piece.

[0007] Preferably, an elastic sleeve is fixedly connected to the inner wall of the protective sleeve. The elastic sleeve has a hollow structure inside. A set of grooves is provided on the outer side of the outer protective sleeve layer. The inner wall of the elastic sleeve fits into the grooves.

[0008] Preferably, the protective sleeve has a hollow groove inside, and a push plate is slidably connected to the inner wall of the hollow groove. A through hole communicating with the hollow groove is opened on one side of the protective sleeve. A first spring is fixedly connected between the side of the push plate near the through hole and the inner wall of the hollow groove. A first connecting hole is opened on the inner wall of the protective sleeve. A second connecting hole communicating with the first connecting hole is opened on the outer wall of the elastic sleeve. A limiting component for limiting the push plate is provided inside the protective sleeve.

[0009] Preferably, the limiting component includes a connecting rod that is slidably and sealingly connected to the side wall of the protective sleeve, a first magnetic block is fixedly connected to the side of the push plate near the connecting rod, a second magnetic block that repels the first magnetic block is fixedly connected to the bottom surface of the connecting rod, and a second spring is fixedly connected between the bottom surface of the connecting rod and the inner wall of the hollow groove.

[0010] A method for preparing a high-toughness power cable, the method comprising the following steps: S1: Select copper or aluminum wire as the conductor substrate, and twist multiple strands of fine conductor wires according to the standard that the twisting pitch is 10-15 times the conductor diameter, using a regular twisting method; S2: Modified cross-linked polyethylene is selected as the insulation layer. After being heated and melted, it is uniformly extruded onto the surface of the stranded conductor prepared in S1 through an extruder. The extrusion thickness is controlled at 1.5-5.0 mm according to the cable voltage level. The temperature is controlled at 120-150℃ during the extrusion process to ensure that the insulation layer is free of bubbles and cracks and is tightly bonded to the conductor. At the same time, an arc transition treatment is adopted on the surface of the insulation layer. S3: A layer of polyurethane or nitrile rubber buffer interlayer is uniformly laid on the surface of the insulation layer prepared in S2. The thickness of the buffer interlayer is controlled between 0.5-1.2mm. During the laying process, it is ensured that there are no wrinkles or gaps between the layers. It is fixed to the insulation layer by hot pressing. S4: First, an inner sheath layer with a thickness of 0.8-1.5mm is extruded onto the surface of the buffer interlayer; then, aluminum alloy strip is spirally wound onto the surface of the inner sheath layer at a winding angle of 30-45° to form an armor layer; finally, an outer sheath layer is extruded onto the surface of the armor layer. Both the inner and outer sheath layers are made of polyolefin material, with an extrusion thickness of 1.0-2.0mm. S5: The manufactured high-toughness power cable is inspected for appearance, dimensions, elongation at break and bending performance. The tensile strength of the cable is tested using a tensile testing machine. After passing the test, the cable is wound up to the specified length to complete the preparation of the high-toughness power cable.

[0011] The method of using the protective sleeve includes the following steps: A1: Press down on the connecting rod to align the second magnetic block with the first magnetic block. Under the action of repulsion, the push plate moves away from the connecting rod, causing the gas inside the elastic sleeve to be drawn into the hollow groove, causing the elastic sleeve to deflate. A2: Place the deflated elastic sleeve onto the cable body, move the connecting rod upward to misalign the second magnetic block with the first magnetic block, and cause the first spring to push the push plate, allowing the gas in the hollow groove to enter the elastic sleeve, causing the elastic sleeve to expand and be squeezed and fixed to the cable body. A3: Place the cable body and make the drive wheel and support wheel contact the ground to assist the cable body in moving on the ground. After the cable body reaches the preset position, remove the protective sleeve from the cable body.

[0012] Preferably, the tensile testing machine in S5 includes a testing platform, a first connecting plate is fixedly connected to the top surface of the testing platform, a set of first round rods is fixedly connected to the outer side wall of the first connecting plate, an automatically moving lifting frame is provided on the testing platform, a second connecting plate is provided on the lifting frame, and a second round rod corresponding to the first round rod is provided on the outer side of the second connecting plate.

[0013] Preferably, a set of sliding grooves is provided on the outer side wall of the second connecting plate, a sliding plate is slidably connected in the sliding groove, one end of the second round rod is fixedly connected to the sliding plate, an air spring is fixedly connected between the bottom surface of the sliding plate and the inner wall of the sliding groove, and a pressure sensor is fixedly connected to the inner wall of the sliding groove.

[0014] Preferably, the second connecting plate has a cavity, and a drive plate is slidably connected to the cavity. A third spring is fixedly connected between the bottom surface of the drive plate and the inner wall of the cavity. An electromagnet that magnetically attracts the drive plate is fixedly connected to the bottom surface of the inner wall of the cavity. The second connecting plate has an annular groove that communicates with the cavity. A connecting pipe is connected between the annular groove and the air spring. A solenoid valve is installed in the connecting pipe.

[0015] The beneficial effects of this invention are as follows: 1. This invention prepares a flexible multi-strand stranded conductor by stranding multiple fine conductor wires with a stranding pitch of 10-15 times the conductor diameter using a standard stranding method. During stranding, the tension is controlled to be uniform, avoiding wire breakage and loose strands. This improves the conductor's inherent toughness and reduces stress concentration during subsequent bending. The insulation layer uses modified cross-linked polyethylene (XLPE) as the insulation material, and the buffer interlayer can be made of polyurethane or nitrile rubber. The thickness of the buffer interlayer is controlled between 0.5-1.2 mm. During installation, it is ensured that there are no wrinkles or gaps between the layers. The interlayer is fixed to the insulation layer by hot-pressing, absorbing external impact and bending stress, further improving the cable's toughness.

[0016] 2. In this invention, the inner sheath layer is extruded onto the buffer interlayer with a thickness of 0.8-1.5mm. The outer sheath layer is made of a polyolefin material with excellent aging resistance and flexibility, with an extrusion thickness of 1.0-2.0mm. This ensures that the composite protective layer has both toughness and impact resistance. The drive wheel on the protective sleeve can prevent the power cable from directly contacting the ground when being dragged, thus avoiding unnecessary friction on the outer sheath layer and affecting its toughness. Attached Figure Description

[0017] The invention will now be further described with reference to the accompanying drawings.

[0018] Figure 1 This is a schematic diagram of the cable body structure in this invention; Figure 2 This is a front view of the cable body of the present invention; Figure 3 This is a schematic diagram of the internal structure of the protective sleeve elastic sleeve in this invention; Figure 4 yes Figure 3 A schematic diagram of a partial structure; Figure 5 This is a flowchart of the preparation method in this invention; Figure 6 This is a flowchart illustrating the method of using the protective sleeve in this invention; Figure 7 This is a schematic diagram of the tensile testing machine in this invention; Figure 8 This is a schematic diagram of the structure of the second connecting disk in this invention; Figure 9 This is a schematic diagram of the internal structure of the second connecting disk in this invention.

[0019] In the diagram: 1. Cable body; 2. Guide wire; 3. Insulation layer; 4. Buffer interlayer; 5. Inner sheath layer; 6. Armor layer; 7. Outer sheath layer; 8. Drive wheel; 9. Groove; 10. Protective sleeve; 11. Elastic sleeve; 12. Support wheel; 13. Support frame; 14. Connecting piece; 15. First spring; 16. Push plate; 17. Through hole; 18. First connecting hole; 19. Second connecting hole; 20. First magnet; 21. Connecting rod; 22. Second magnet; 23. Detection table; 24. First connecting plate; 25. First round rod; 26. Lifting frame; 27. Second connecting plate; 28. Slide groove; 29. ​​Slide plate; 30. Second round rod; 31. Air spring; 32. Pressure sensor; 33. Hollow groove; 34. Drive plate; 35. Electromagnet; 36. Annular groove; 37. Connecting pipe. Detailed Implementation

[0020] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.

[0021] Example 1: As Figures 1 to 5 As shown in the figure, a high-toughness power cable according to an embodiment of the present invention includes a cable body 1, the cable body 1 including a guide wire 2, an insulation layer 3, a buffer interlayer 4 and a composite protective layer; the composite protective layer includes an inner sheath layer 5, an armor layer 6 and an outer sheath layer 7; the inner sheath layer 5 is sleeved on the buffer interlayer 4, the armor layer 6 is an aluminum alloy strip, and is spirally wound on the inner sheath layer 5 at a winding angle of 30-45°; both the inner sheath layer 5 and the outer sheath layer 7 are made of polyolefin material, and a protective sleeve 10 is provided on the outer sheath layer 7, and a drive wheel 8 is rotatably connected to the outer side wall of the protective sleeve 10; In this invention, the guide wire 2 can be made of copper or aluminum wire as the conductor substrate. Multiple strands of fine conductor wire are stranded using a standard stranding method with a stranding pitch of 10-15 times the conductor diameter. During stranding, the tension is controlled to be uniform, avoiding wire breakage and loose strands. This process produces a flexible multi-strand stranded conductor, improving the conductor's inherent toughness and reducing stress concentration during subsequent bending. The insulation layer 3 uses modified cross-linked polyethylene (XLPE) as the insulation material. The buffer layer 4 can be made of polyurethane or nitrile rubber, with a thickness controlled between 0.5-1.2 mm. During the laying process, it is ensured that there are no wrinkles or gaps between the layers. It is fixed to the insulation layer 3 by hot pressing to absorb the stress of external impact and bending, and further improve the toughness of the cable. The inner sheath layer 5 is extruded onto the buffer interlayer 4 with a thickness of 0.8-1.5mm. The outer sheath layer 7 is made of polyolefin material with good aging resistance and flexibility, with an extrusion thickness of 1.0-2.0mm, to ensure that the composite protective layer takes into account both toughness and impact resistance. The drive wheel 8 on the protective sleeve 10 can prevent the power cable from directly contacting the ground when it is dragged and moving, so as to avoid unnecessary friction on the outer sheath layer 7 and affect its toughness.

[0022] A pair of symmetrically arranged support frames 13 are fixedly connected to the outer wall of the protective sleeve 10. An arc-shaped connecting piece 14 is fixedly connected to the bottom end of the support frame 13. A support wheel 12 is rotatably connected to the inner wall of the connecting piece 14. When the cable body 1 in this application is dragged and moved, the support wheel 12 can provide auxiliary support to prevent the cable body 1 from tilting due to the single-point support of the drive wheel 8, which would cause unnecessary wear to the cable body 1.

[0023] An elastic sleeve 11 is fixedly connected to the inner wall of the protective sleeve 10. The elastic sleeve 11 has a hollow structure inside. A set of grooves 9 are provided on the outer side of the outer sheath layer 7, and the inner wall of the elastic sleeve 11 fits into the grooves 9. In this application, the elastic sleeve 11 allows the protective sleeve 10 to be fitted onto the cable body 1. At the same time, due to the elasticity of the elastic sleeve 11, the protective sleeve 10 can be adapted to different sizes and models of cable bodies 1 for use. Furthermore, the cooperation between the grooves 9 and the elastic sleeve 11 can improve the stability of the elastic sleeve 11 on the outer sheath layer 7.

[0024] The protective sleeve 10 has a hollow groove 33 inside, and a push plate 16 is slidably connected to the inner wall of the hollow groove 33. A through hole 17 communicating with the hollow groove 33 is opened on one side of the protective sleeve 10. A first spring 15 is fixedly connected between the side of the push plate 16 near the through hole 17 and the inner wall of the hollow groove 33. A first connecting hole 18 is opened on the inner wall of the protective sleeve 10. A second connecting hole 19 communicating with the first connecting hole 18 is opened on the outer wall of the elastic sleeve 11. A limiting component for limiting the push plate 16 is provided inside the protective sleeve 10. In this application, the inner diameter of the elastic sleeve 11 is smaller than the outer diameter of the cable body 1, so that the elastic sleeve 11 can be easily fitted onto the cable body 1. After the elastic sleeve 11 is fitted onto the cable body 1, the limiting component no longer limits the push plate 16. At this time, the first spring 15 will push the push plate 16, so that the push plate 16 pushes the gas in the hollow groove 33. The gas will then pass through the first connecting hole 18 and the second connecting hole 19, and then enter the elastic sleeve 11, causing the elastic sleeve 11 to expand and press against the cable body 1, thereby fixing the protective sleeve 10 onto the cable body 1.

[0025] The limiting component includes a connecting rod 21 that is slidably and sealingly connected to the side wall of the protective sleeve 10. A first magnetic block 20 is fixedly connected to the side of the push plate 16 near the connecting rod 21. A second magnetic block 22 that repels the first magnetic block 20 is fixedly connected to the bottom surface of the connecting rod 21. A second spring is fixedly connected between the bottom surface of the connecting rod 21 and the inner wall of the hollow groove 33. When the elastic sleeve 11 needs to be fitted onto the cable body 1, the connecting rod 21 is pressed down to align the second magnetic block 22 with the first magnetic block 20. At this time, the push plate 16 will move away from the connecting rod 21 due to the repulsive force. At this time, the gas in the elastic sleeve 11 will be drawn into the hollow groove 33. Then, when the elastic sleeve 11 is in a suitable position on the cable body 1, the connecting rod 21 is released. At this time, the second spring will push the connecting rod 21 upward, causing the second magnetic block 22 to be misaligned with the first magnetic block 20. At this time, the first spring 15 will push the push plate 16 to allow the gas in the hollow groove 33 to enter the elastic sleeve 11.

[0026] Example 2: Figures 6 to 9As shown, a method for preparing a high-toughness power cable is described. This method, used to prepare the aforementioned high-toughness power cable, includes the following steps: S1: Select copper or aluminum wire as the conductor substrate, and strand multiple fine conductor wires are stranded according to the standard that the stranding pitch is 10-15 times the conductor diameter, and the tension is controlled to be uniform during the stranding process. S2: Modified cross-linked polyethylene (XLPE) is selected as the insulation layer 3. After being heated and melted, it is uniformly extruded onto the surface of the stranded conductor prepared in S1 through an extruder. The extrusion thickness is controlled at 1.5-5.0 mm according to the cable voltage level. The temperature is controlled at 120-150℃ during the extrusion process to ensure that the insulation layer 3 is free of bubbles and cracks and is tightly bonded to the conductor. At the same time, an arc transition treatment is adopted on the surface of the insulation layer 3 to avoid right angle structures. S3: A layer of polyurethane or nitrile rubber buffer layer 4 is uniformly laid on the surface of the insulating layer 3 prepared in S2. The thickness of the buffer layer 4 is controlled at 0.5-1.2mm. During the laying process, it is ensured that there are no wrinkles or gaps between the layers. It is fixed to the insulating layer 3 by hot pressing. S4: Preparation of the composite protective layer: First, an inner sheath layer 5 with a thickness of 0.8-1.5mm is extruded onto the surface of the buffer interlayer 4. Then, aluminum alloy strip is spirally wound onto the surface of the inner sheath layer 5 at a winding angle of 30-45° to form the armor layer 6. Finally, an outer sheath layer 7 is extruded onto the surface of the armor layer 6. Both the inner sheath layer 5 and the outer sheath layer 7 are made of polyolefin material with excellent aging resistance and flexibility, with an extrusion thickness of 1.0-2.0mm. S5: The finished high-toughness power cable is inspected for appearance, dimensions, elongation at break, and bending performance. At the same time, a tensile testing machine is used to test the tensile strength of the cable. Products with surface damage, dimensional deviations, and substandard toughness are rejected. After passing the inspection, the cable is wound up to the specified length, marked, and the preparation of the high-toughness power cable is completed.

[0027] The method of using the protective sleeve 10 includes the following steps: A1: Press down on the connecting rod 21 to align the second magnet 22 with the first magnet 20. At this time, the push plate 16 will move away from the connecting rod 21 due to the repulsive force. At this time, the gas in the elastic sleeve 11 will be drawn into the hollow groove 33, causing the elastic sleeve 11 to deflate. A2: Place the deflated elastic sleeve 11 on the appropriate position of the cable body 1, and then move the connecting rod 21 upward so that the second magnetic block 22 is misaligned with the first magnetic block 20. At this time, the first spring 15 will push the push plate 16 to allow the gas in the hollow groove 33 to enter the elastic sleeve 11. At this time, the elastic sleeve 11 will expand and squeeze to fix itself to the cable body 1. A3: After the protective sleeve 10 is fixed on the cable body 1, place the cable body 1 on the ground, and at the same time make the drive wheel 8 and support wheel 12 contact the ground to assist the cable body 1 in moving on the ground. After the cable body 1 reaches the preset position, remove the protective sleeve 10 from the cable body 1.

[0028] The tensile testing machine in S5 includes a testing platform 23. A first connecting plate 24 is fixedly connected to the top surface of the testing platform 23. A set of first round rods 25 are fixedly connected to the outer side wall of the first connecting plate 24. An automatically moving lifting frame 26 is provided on the testing platform 23. A second connecting plate 27 is provided on the lifting frame 26. A second round rod 30 corresponding to the first round rods 25 is provided on the outer side of the second connecting plate 27. Current tensile testing machines typically only perform tensile tests on one cable body 1. Tensile test is a toughness test, which is inefficient. This application can prepare the sample of the cable body 1 to be tested in advance (the cable body 1 will be cut off, and only a small section needs to be used for testing). Then, the two ends of the cable body 1 are fixed on the first round rod 25 and the second round rod 30 respectively. Then, the lifting frame 26 controls the second connecting plate 27 to move upward, so that all cable bodies 1 can be tested simultaneously, which greatly improves the efficiency of the test. The tensile test can detect whether the cable body 1 meets the standard of high toughness.

[0029] The outer wall of the second connecting plate 27 is provided with a set of sliding grooves 28, and a sliding plate 29 is slidably connected in the sliding grooves 28. One end of the second round rod 30 is fixedly connected to the sliding plate 29. An air spring 31 is fixedly connected between the bottom surface of the sliding plate 29 and the inner wall of the sliding groove 28. A pressure sensor 32 is fixedly connected to the inner wall of the sliding groove 28. When the cable body 1 is subjected to tensile testing, the lifting frame 26 will control the second connecting plate 27 to move to a fixed position. At this time, the sliding plate 29 will be pulled downward. If there is a cable body 1 with unqualified toughness, the sliding plate 29 at its connection point will contact the pressure sensor 32. Then the testing platform 23 will sound an alarm to alert the staff.

[0030] The second connecting plate 27 has a cavity, and a drive plate 34 is slidably connected to the cavity. A third spring is fixedly connected between the bottom surface of the drive plate 34 and the inner wall of the cavity. An electromagnet 35, which is magnetically attracted to the drive plate 34, is fixedly connected to the bottom surface of the inner wall of the cavity. An annular groove 36 communicating with the cavity is formed in the second connecting plate 27. A connecting pipe 37 is connected between the annular groove 36 and the air spring 31. A solenoid valve is installed in the connecting pipe 37. By controlling the magnetic force of the electromagnet 35, this application can control the degree of vertical movement of the drive plate 34. When the drive plate 34 moves downward, it pushes the gas in the cavity, which then enters the air spring 31 to change the stiffness of the cavity spring, so as to adapt to different tensile testing requirements and improve the tensile testing effect of the entire equipment.

[0031] Working principle: The elastic sleeve 11 allows the protective sleeve 10 to be fitted onto the cable body 1. Due to the elasticity of the elastic sleeve 11, the protective sleeve 10 can be adapted to different sizes and models of cable bodies 1. In this application, the inner diameter of the elastic sleeve 11 is smaller than the outer diameter of the cable body 1 to facilitate the fitting of the elastic sleeve 11 onto the cable body 1. After the elastic sleeve 11 is fitted onto the cable body 1, the limiting component no longer limits the push plate 16. At this time, the first spring 15 pushes the push plate 16, causing the push plate 16 to push the gas in the hollow groove 33. The gas then passes through the first connecting hole 18 and the second connecting hole 19, and then enters the elastic sleeve 11, causing the elastic sleeve 11 to expand and press against the cable body 1, thereby fixing the protective sleeve 10 onto the cable body 1. When the elastic sleeve 11 needs to be fitted onto the cable body 1, the connecting rod 21 is pressed down to align the second magnet 22 with the first magnet 20. At this time, the push plate 16 will move away from the connecting rod 21 due to the repulsive force. At this time, the gas inside the elastic sleeve 11 will be drawn into the hollow groove 33. Then, the elastic sleeve 11 is positioned appropriately on the cable body 1. The connecting rod 21 is then released. At this time, the second spring will push the connecting rod 21 upward, causing the second magnet 22 to misalign with the first magnet 20. At this time, the first spring 15 will push the push plate 16, allowing the gas in the hollow groove 33 to enter the elastic sleeve 11. Subsequently, with the help of the support wheel 12 and the drive wheel 8, the power cable can be prevented from directly contacting the ground when being dragged. Unnecessary friction in the sheath layer 7 affects its toughness. During the tensile test of the cable body 1, the lifting frame 26 controls the second connecting plate 27 to move to a fixed position. At this time, the sliding plate 29 will be pulled downward. If the cable body 1 has unqualified toughness, the sliding plate 29 at its connection point will contact the pressure sensor 32. Subsequently, the testing platform 23 will sound an alarm to alert the staff. This application can control the degree of up and down movement of the drive plate 34 by controlling the magnetic force of the electromagnet 35. When the drive plate 34 moves downward, it will push the gas in the cavity and then enter the air spring 31 to change the softness and hardness of the cavity spring to adapt to different tensile test requirements and improve the tensile test effect of the whole set of equipment.

[0032] The terms "front," "back," "left," "right," "top," and "bottom" all refer to the figures in the accompanying drawings. Figure 1 Based on the perspective of the observer, the side of the device facing the observer is defined as the front, the left side of the observer is defined as the left, and so on.

[0033] In the description of this invention, it should be understood that the terms "center", "longitudinal", "lateral", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the scope of protection of this invention.

[0034] 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 illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, 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 high-toughness power cable, comprising a cable body (1), wherein the cable body (1) comprises a guide wire (2), an insulation layer (3), a buffer interlayer (4), and a composite protective layer; Its features are: The composite protective layer includes an inner sheath layer (5), an armor layer (6), and an outer sheath layer (7). The inner sheath layer (5) is sleeved on the buffer interlayer (4), and the armor layer (6) is an aluminum alloy strip, which is spirally wound on the inner sheath layer (5) at a winding angle of 30-45°. The inner sheath layer (5) and the outer sheath layer (7) are both made of polyolefin material. A protective sleeve (10) is provided on the outer sheath layer (7), and a drive wheel (8) is rotatably connected to the outer side wall of the protective sleeve (10).

2. The high-toughness power cable according to claim 1, characterized in that: The outer wall of the protective sleeve (10) is fixedly connected to a pair of symmetrically arranged support frames (13), the bottom end of the support frame (13) is fixedly connected to an arc-shaped connecting piece (14), and the inner wall of the connecting piece (14) is rotatably connected to a support wheel (12).

3. A high-toughness power cable according to claim 2, characterized in that: The inner wall of the protective sleeve (10) is fixedly connected to an elastic sleeve (11), and the inside of the elastic sleeve (11) is a hollow structure; a set of grooves (9) are provided on the outer side of the outer protective sleeve layer (7), and the inner wall of the elastic sleeve (11) fits into the grooves (9).

4. A high-toughness power cable according to claim 3, characterized in that: The protective sleeve (10) has a hollow groove (33) inside. The inner wall of the hollow groove (33) is slidably connected to a push plate (16). One side of the protective sleeve (10) has a through hole (17) communicating with the hollow groove (33). The side of the push plate (16) near the through hole (17) is fixedly connected to the inner wall of the hollow groove (33) with a first spring (15). The inner wall of the protective sleeve (10) has a first connecting hole (18). The outer wall of the elastic sleeve (11) has a second connecting hole (19) communicating with the first connecting hole (18). The protective sleeve (10) is provided with a limiting component to limit the push plate (16).

5. A high-toughness power cable according to claim 4, characterized in that: The limiting assembly includes a connecting rod (21) that is slidably and sealingly connected to the side wall of the protective sleeve (10). A first magnetic block (20) is fixedly connected to the side of the push plate (16) near the connecting rod (21). A second magnetic block (22) that repels the first magnetic block (20) is fixedly connected to the bottom surface of the connecting rod (21). A second spring is fixedly connected between the bottom surface of the connecting rod (21) and the inner wall of the hollow groove (33).

6. A method for preparing a high-toughness power cable, the method being used to prepare the high-toughness power cable of claim 5, characterized in that: The method includes the following steps: S1: Select copper or aluminum wire as the conductor substrate, and twist multiple strands of fine conductor wires according to the standard that the twisting pitch is 10-15 times the conductor diameter, using a regular twisting method; S2: Modified cross-linked polyethylene is selected as the insulation layer (3). After heating and melting, it is uniformly extruded onto the surface of the stranded conductor prepared in S1 through an extruder. The extrusion thickness is controlled at 1.5-5.0 mm according to the cable voltage level. The temperature is controlled at 120-150℃ during the extrusion process to ensure that the insulation layer (3) is free of bubbles and cracks and is tightly attached to the conductor. At the same time, an arc transition treatment is adopted on the surface of the insulation layer (3). S3: A layer of polyurethane or nitrile rubber buffer interlayer (4) is uniformly laid on the surface of the insulating layer (3) prepared in S2. The thickness of the buffer interlayer (4) is controlled at 0.5-1.2mm. During the laying process, it is ensured that there are no wrinkles or gaps between the layers. It is fixed to the insulating layer (3) by hot pressing. S4: First, an inner sheath layer (5) with a thickness of 0.8-1.5mm is extruded onto the surface of the buffer interlayer (4); then, aluminum alloy strip is spirally wound onto the surface of the inner sheath layer (5) at a winding angle of 30-45° to form an armor layer (6); finally, an outer sheath layer (7) is extruded onto the surface of the armor layer (6). Both the inner sheath layer (5) and the outer sheath layer (7) are made of polyolefin material, with an extrusion thickness of 1.0-2.0mm. S5: The manufactured high-toughness power cable is inspected for appearance, dimensions, elongation at break and bending performance. The tensile strength of the cable is tested using a tensile testing machine. After passing the test, the cable is wound up to the specified length to complete the preparation of the high-toughness power cable.

7. The method for preparing a high-toughness power cable according to claim 6, characterized in that: The method of using the protective sleeve (10) includes the following steps: A1: Press down on the connecting rod (21) to align the second magnetic block (22) with the first magnetic block (20). The push plate (16) moves away from the connecting rod (21) under the action of repulsion, so that the gas in the elastic sleeve (11) is drawn into the hollow groove (33) and the elastic sleeve (11) is deflated. A2: Place the deflated elastic sleeve (11) onto the cable body (1), move the connecting rod (21) upward, so that the second magnetic block (22) is misaligned with the first magnetic block (20), so that the first spring (15) pushes the push plate (16), so that the gas in the hollow groove (33) enters the elastic sleeve (11), so that the elastic sleeve (11) expands and is squeezed and fixed on the cable body (1). A3: Place the cable body (1) and make the drive wheel (8) and support wheel (12) contact the ground to assist the cable body (1) in moving on the ground. After the cable body (1) reaches the preset position, remove the protective sleeve (10) from the cable body (1).

8. The method for preparing a high-toughness power cable according to claim 7, characterized in that: The tensile testing machine in S5 includes a testing platform (23), a first connecting plate (24) is fixedly connected to the top surface of the testing platform (23), a set of first round rods (25) is fixedly connected to the outer side wall of the first connecting plate (24), an automatically moving lifting frame (26) is provided on the testing platform (23), a second connecting plate (27) is provided on the lifting frame (26), and a second round rod (30) corresponding to the first round rod (25) is provided on the outer side of the second connecting plate (27).

9. The method for preparing a high-toughness power cable according to claim 8, characterized in that: The outer side wall of the second connecting plate (27) is provided with a set of sliding grooves (28), and a sliding plate (29) is slidably connected in the sliding grooves (28). One end of the second round rod (30) is fixedly connected to the sliding plate (29). An air spring (31) is fixedly connected between the bottom surface of the sliding plate (29) and the inner wall of the sliding groove (28). A pressure sensor (32) is fixedly connected to the inner wall of the sliding groove (28).

10. The method for preparing a high-toughness power cable according to claim 9, characterized in that: The second connecting plate (27) has a cavity, and a drive plate (34) is slidably connected in the cavity. A third spring is fixedly connected between the bottom surface of the drive plate (34) and the inner wall of the cavity. An electromagnet (35) magnetically attracted to the drive plate (34) is fixedly connected to the bottom surface of the inner wall of the cavity. An annular groove (36) communicating with the cavity is opened in the second connecting plate (27). A connecting pipe (37) is connected between the annular groove (36) and the air spring (31). A solenoid valve is installed in the connecting pipe (37).

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