Smooth aluminum sheathed low voltage cable

Abstract

The present invention discloses a smooth aluminum sheathed low-voltage cable, wherein the outer periphery of a water-blocking aluminum conductor is coated with a conductor shielding layer; the outer periphery of the conductor shielding layer is coated with a polypropylene insulation layer; the outer periphery of the polypropylene insulation layer is coated with an insulation shielding layer; the outer periphery of the insulation shielding layer is coated with a first semi-conductive water-swelling tape; the outer periphery of the semi-conductive water-swelling tape is coated with a copper wire shielding layer; the outer periphery of the copper wire shielding layer is wrapped with a tightening copper tape layer; the outer periphery of the tightening copper tape layer is coated with a second semi-conductive water-swelling tape; the outer periphery of the second semi-conductive water-swelling tape is provided with an aluminum-plastic composite tape layer; the outer periphery of the aluminum-plastic composite tape layer is provided with a polymer sheathing layer; the outer periphery of the polymer sheathing layer is provided with an aluminum sheathing layer; the outer periphery of the aluminum sheathing layer is provided with a tape layer; the outer periphery of the tape layer is provided with a PE sheathing layer; the outer periphery of the PE sheathing layer is provided with a galvanized steel wire armoring layer, and the outer periphery of the PE sheathing layer is provided with two protective layers. The smooth aluminum sheathed low-voltage cable of the present invention has high mechanical strength and strong waterproof and corrosion resistance.

Description

Technical Field

[0001] The invention relates to a smooth aluminum sheathed low-voltage cable. Background Art

[0002] With the continuous development of society and the accelerating pace of urbanization, electricity loads are increasing, and the safety requirements for power supply and transmission systems are becoming increasingly stringent. Simultaneously, driven by the need for urban beautification and the national push for urban grid transformation, there is an increasing demand for large-section, long-length power cables, enabling the undergrounding of overhead lines to enhance urban aesthetics. Large-scale engineering projects, such as tunnel cable laying and cables used in petrochemical plants, place stringent requirements on waterproofing and corrosion resistance against oils and chemical solvents. Cables used in these applications must not only maintain the mechanical, physical, and electrical properties of conventional plastic-insulated and sheathed power cables, but also exhibit high waterproofing, corrosion resistance, interference immunity, and resistance to strong mechanical impact.

[0003] Currently, conventional waterproof cables on the market utilize a structure comprised of cross-linked polyethylene insulation, a corrugated aluminum sheath, an environmentally friendly modified polypropylene insulation and smooth aluminum sheath, a semi-conductive buffer resistor layer, a corrugated aluminum sheath, and an asphalt coating for waterproofing and corrosion resistance. However, these structures lack the waterproofing, corrosion resistance, interference immunity, and mechanical shock resistance required for long-term installation in specialized locations. Over time, these cables are prone to breakage and disconnection, compromising electrical safety in large-scale facilities. Summary of the Invention

[0004] The present invention provides a smooth aluminum sheathed low-voltage cable to solve the above-mentioned technical problems, specifically adopting the following technical solutions:

[0005] A smooth aluminum sheathed low-voltage cable, comprising: a water-blocking aluminum conductor; a conductor shielding layer for fastening the water-blocking aluminum conductor to shield the water-blocking aluminum conductor, which is coated on the outer periphery of the water-blocking aluminum conductor; a polypropylene insulation layer for insulating the conductor, which is coated on the outer periphery of the polypropylene insulation layer; an insulating shielding layer for protecting the polypropylene insulation layer, which is coated on the outer periphery of the insulating shielding layer; a first semi-conductive water-swelling tape for improving waterproof performance, which is coated on the outer periphery of the semi-conductive water-swelling tape; a copper wire shielding layer for electrical shielding, which is coated on the outer periphery of the copper wire shielding layer; a second semi-conductive water-swelling tape for waterproofing the internal metal material, which is coated on the outer periphery of the tightening copper tape layer; and a second The outer periphery of the semiconductor water-resistant expansion tape is provided with an aluminum-plastic composite tape layer for improving the structural strength and stress absorption capacity of the cable; the outer periphery of the aluminum-plastic composite tape layer is provided with a polymer sheath layer for buffering the torsional stress of the cable; the outer periphery of the polymer sheath layer is provided with an aluminum sheath layer for improving the water-blocking performance; the outer periphery of the aluminum sheath layer is provided with a tape layer for further waterproofing; the outer periphery of the tape layer is provided with a PE sheath layer for protecting the internal structure of the cable; the outer periphery of the PE sheath layer is provided with a galvanized steel wire armor layer for improving the mechanical strength of the cable; the outer periphery of the galvanized steel wire armor layer is provided with an outer sheath layer for elastically supporting and protecting the galvanized steel wire armor layer; the outer periphery of the outer sheath layer is provided with a nylon protective layer for improving the dragging smoothness and support of the cable.

[0006] Furthermore, a plurality of mutually engaging mutually embedded parts are formed on the side where the nylon protective layer and the outer sheath layer contact each other; a plurality of outward-facing steel wires are woven circumferentially on the outer periphery of the galvanized steel wire armor layer through a weaving process; a clamping hole for clamping the outward-facing steel wire is formed on the side of the outer sheath layer for contacting the galvanized steel wire armor layer; the groove bottom of the clamping hole extends into the mutually embedded part, so that the outward-facing steel wire and the mutually embedded part form a connected whole.

[0007] Furthermore, the multiple outward-facing steel wires and the mutually embedded parts form a connected whole, and are jointly penetrated by a first connecting steel wire for connecting the multiple wholes in series into a braided whole; the first connecting steel wire is spirally shaped and is penetrated on the inner side of the outward-facing steel wire when spirally shaped.

[0008] Furthermore, a plurality of inward-spreading steel wires are woven circumferentially on the inner periphery of the galvanized steel wire armor layer by a weaving process; the PE sheath layer is formed with embedding holes for embedding and installing the inward-spreading steel wires; and the inward-spreading steel wires are embedded and installed in the groove bottoms of the embedding holes.

[0009] Furthermore, a second series-connected steel wire is passed through the PE sheath layer; the second series-connected steel wire is spirally shaped and passed through the inner side of the inner-extended steel wire when spirally connected.

[0010] Furthermore, both stripped ends of a smooth aluminum sheathed low-voltage cable are sleeved with compression rings for compressing both ends of the cable;

[0011] The clamping ring is provided with a fixing portion for fixing to a location where the cable is connected.

[0012] Furthermore, the clamping ring is also provided with a connecting portion for fixedly connecting the portions of the first series-connected steel wire and the second series-connected steel wire extending out of the cable.

[0013] Furthermore, the connecting portion is formed with a self-locking rod and a self-locking plug rod for self-locking the first series steel wire and the second series steel wire; the self-locking plug rod is detachably inserted into the plug hole formed in the connecting portion and is arranged parallel to the self-locking rod; the first series steel wire or the second series steel wire is wound along the overall outer periphery formed by the self-locking rod and the self-locking plug rod, and the terminal is fixed in the connecting hole at one end of the self-locking plug rod; the self-locking plug rod is pulled out in the opposite direction of the spiral winding of the first series steel wire or the second series steel wire; the end of the first series steel wire or the second series steel wire is locked by the part of itself that is wound, and the self-locking plug rod locks the end of the first series steel wire or the second series steel wire to prevent it from falling off.

[0014] Furthermore, the spiral directions of the first series-connected steel wire and the second series-connected steel wire are opposite.

[0015] Furthermore, a clamping foot for gripping the copper wires of the copper wire shielding layer is formed on the inner side of the tightening copper tape layer; the copper tape of the tightening copper tape layer is a mesh structure with high mechanical ductility.

[0016] The present invention is beneficial in that the overall structure of the smooth aluminum sheathed low-voltage cable provided is mechanically strong, making it less susceptible to breakage or disconnection during long-term use. The cable exhibits strong torsion and tensile strength during installation, making it suitable for a variety of cable installation sites. The cable body structure facilitates installation and prevents twisting. Furthermore, the smooth aluminum sheathed low-voltage cable provided by this solution has superior waterproof and corrosion resistance, strong impact resistance, and excellent shockproof properties. It also offers a longer lifespan when installed for extended periods, is less prone to line problems, and ensures safety at power-using sites. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0018] Figure 1 is a schematic diagram of a smooth aluminum sheathed low-voltage cable involved in this application;

[0019] A smooth aluminum sheathed low-voltage cable 10 includes a water-blocking aluminum conductor 11, a conductor shielding layer 12, a polypropylene insulation layer 13, an insulation shielding layer 14, a first semi-conductive water-swellable tape 15, a copper wire shielding layer 16, a tightening copper tape layer 17, a second semi-conductive water-swellable tape 18, an aluminum-plastic composite tape layer 19, a polymer sheath layer 20, an aluminum sheath layer 21, a tape layer 22, a PE sheath layer 23, an embedding hole 231, a galvanized steel wire armor layer 24, an outwardly extending steel wire 241, an innerly extending steel wire 242, an outer sheath layer 25, a clamping hole 251, a nylon protective layer 26, a mutually embedded portion 27, a first series-connected steel wire 28, a second series-connected steel wire 29, a clamping ring 30, a fixing portion 301, a connecting portion 302, a self-locking rod 303, and a self-locking plug rod 304. DETAILED DESCRIPTION

[0020] The following describes embodiments of the present invention in detail. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to explain the present invention, but are not to be construed as limiting the present invention.

[0021] In the description of the present invention, unless otherwise expressly specified or limited, the terms "connected," "connected," and "fixed" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention in specific circumstances.

[0022] In the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Furthermore, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0023] like Figure 1As shown, a smooth aluminum sheathed low-voltage cable 10 of the present application is used, which adopts a water-blocking aluminum conductor 11 for conduction. The water-blocking aluminum conductor 11 is made of aluminum alloy profiled wire monofilaments compressed and twisted. The profiled wire monofilaments are preferably T-shaped, with a compact structure and a filling factor of up to 98%. Compared with the round monofilament compressed conductor of the same specification (the filling factor does not exceed 92%), the outer diameter of the conductor is smaller, and less material is used to cover the outside of the conductor. In addition, the resistivity of the profiled wire compressed and twisted conductor is lower than that of the round monofilament compressed conductor, and the cross-section is more optimized compared with the same specification, saving materials and costs. The conductivity of the aluminum alloy material of the water-blocking aluminum conductor 11 is 61.5% of the copper IACS, and the current carrying capacity is 79% of copper, which is better than the pure aluminum standard. Compared to pure aluminum conductors: its creep resistance is improved by 300%, preventing relaxation problems caused by cold flow or creep. Aluminum alloy also has greater tensile strength, with a density of 2.71g / cm3 and copper's density of 8.89g / cm3. It can support a 4,000-meter-long deadweight, while copper conductor cables can only support 2,750 meters. Aluminum alloy conductors also have good corrosion resistance. When the surface comes into contact with air, a thin and strong oxide layer is formed, which resists all forms of corrosion.

[0024] The outer periphery of the water-blocking aluminum conductor 11 is covered with a conductor shielding layer 12 for fastening the water-blocking aluminum conductor 11 and shielding the water-blocking aluminum conductor 11. The conductor shielding layer 12 is made of a cross-linked semi-conductive shielding material for conductors and has a thickness of 0.7 mm ± 0.1 mm.

[0025] The conductor shielding layer 12 is covered with a polypropylene insulation layer 13 for insulating the conductor. The polypropylene insulation layer 13 is made of 35kV and below polypropylene insulation material and has a thickness of 10.5mm±0.5mm.

[0026] An insulating shielding layer 14 is coated on the outer periphery of the polypropylene insulating layer 13 to protect the polypropylene insulating layer 13. The insulating shielding layer 14 is made of ultra-smooth semi-conductive shielding material for cross-linked cables and has a thickness of 0.8 mm ± 0.1 mm.

[0027] The outer periphery of the insulating shielding layer 14 is wrapped with a first semiconducting water-swellable tape 15 to improve waterproofing. A copper wire shielding layer 16 is wrapped around the outer periphery of the semiconducting water-swellable tape for electrical shielding. A binding copper tape layer 17 is wrapped around the outer periphery of the copper wire shielding layer 16 for tightening. A second semiconducting water-swellable tape 18 is wrapped around the outer periphery of the binding copper tape layer 17 for waterproofing the internal metal materials. An aluminum-plastic composite tape layer 19 is applied to the outer periphery of the second semiconducting water-swellable tape 18 to enhance the cable's structural strength and stress absorption capacity. The overlap between the first and second semiconducting water-swellable tapes 15, 18 is 15-25%. The copper wire shielding layer 16 is 0.9 mm thick. The binding copper tape layer 17 is made of 0.1 mm thick copper tape, which is reverse-tied.

[0028] As a specific embodiment, a clamping foot for gripping the copper wires of the copper wire shielding layer 16 is formed on the inner side of the tightening copper tape layer 17. The flexible limiting effect of the clamping angle can ensure the stability of the gap distance between the copper wires, thereby ensuring the shielding performance. The structure of the clamping foot can be clearly known from the text description. The distribution position of the clamping foot on one side of the tightening copper tape layer 17 can be designed according to the specific cable size. Since copper has the ability to deform, the position of the clamping foot can have a certain error, which does not affect its clamping and sealing function for the copper wires of the copper wire shielding layer 16. The copper tape that tightens the copper tape layer 17 is a mesh structure with high mechanical ductility. The mesh-shaped copper tape can be elastically expanded and contracted when the cable is wound, ensuring the mechanical elasticity of the cable and the ductility of the cable.

[0029] Furthermore, a polymer sheath layer 20 is provided around the outer periphery of the aluminum-plastic composite tape layer 19 to buffer the torsional stress of the cable. An aluminum sheath layer 21 is provided around the outer periphery of the polymer sheath layer 20 to improve water resistance. A tape layer 22 is provided around the outer periphery of the aluminum sheath layer 21 for further waterproofing.

[0030] The smooth aluminum sheathed low-voltage cable 10 has excellent water-blocking properties. First, the conductor utilizes a water-blocking aluminum conductor 11, which is tightly twisted and twisted, with a fill factor of up to 98%. The gaps between the individual filaments are small, effectively preventing water diffusion. Second, the present invention comprises multiple alternating water-blocking layers, namely: an insulating shielding layer 14, a first semi-conductive water-swelling tape 15, a second semi-conductive water-swelling tape 18, an aluminum-plastic composite tape layer 19, an aluminum sheath layer 21, and a tape layer 22.

[0031] The insulating shielding layer 14, the first semiconducting water-swellable tape 15, the second semiconducting water-swellable tape 18 and the wrapping tape layer 22 have the characteristics of strong water absorption and high expansion rate. They can strongly absorb water and expand rapidly to form a gel-like substance to block the water seepage channel. This constitutes multiple alternating water-blocking layers, which can effectively improve the waterproof performance of the cable.

[0032] In other words, the present invention achieves excellent radial and longitudinal water-blocking effects through the use of multiple alternating water-blocking layers. The arrangement of the copper tape layer 17, the aluminum-plastic composite tape layer 19, the polymer sheath layer 20, and the aluminum sheath layer 21 between the multiple water-blocking layers ensures waterproofing while effectively improving tensile strength, tear resistance, environmental stress resistance (resistance to cracking), low-temperature resistance, heat resistance, and puncture resistance. The aluminum sheath layer 21 utilizes a smooth aluminum sheath 21, providing excellent sealing and a tight fit, effectively preventing the infiltration of water and other corrosive liquids, and providing superior corrosion resistance.

[0033] For smooth aluminum sheaths, argon arc welding is the preferred welding process. Attention should be paid to the inert gas flow rate, welding current, and the distance between the welding core and the welding material to avoid leaks, weak welds, and holes caused by over-welding. Furthermore, the aluminum sheet (strip) used must be smooth, especially the welded areas, to avoid compromising weld quality.

[0034] Based on the above technical solution: a PE sheath layer 23 is provided on the outer periphery of the wrapping layer 22 to protect the internal structure of the cable; a galvanized steel wire armor layer 24 is provided on the outer periphery of the PE sheath layer 23 to improve the mechanical strength of the cable; an outer sheath layer 25 is provided on the outer periphery of the galvanized steel wire armor layer 24 to elastically support and protect the galvanized steel wire armor layer 24; a nylon protective layer 26 is provided on the outer periphery of the outer sheath layer 25 to improve the dragging smoothness and support of the cable.

[0035] The smooth aluminum sheathed low-voltage cable 10 of the present invention utilizes a smooth aluminum sheathed aluminum sheath layer 21 combined with an outer galvanized steel wire armor layer 24, exhibiting excellent mechanical and electrical properties: ① Excellent tensile strength, capable of withstanding significant tensile forces, making it less susceptible to damage during installation and traction, and capable of withstanding significant weight even in locations with large drop heights; ② Excellent compressive strength, eliminating the need for steel belting when laying underground, and protecting the internal conductor core from damage when laying on gravel surfaces; ③ Excellent creep resistance, preventing deformation of the metal lattice and potential damage to the cable under the influence of weight, temperature, and internal forces; ④ Excellent vibration resistance, eliminating the need for additional anti-vibration devices in locations subject to normal vibration, such as bridges, railways, and highways; ⑤ The aluminum sheath and galvanized steel wire provide excellent shielding properties, shielding against surrounding electromagnetic interference and ensuring stable current and signal transmission. Their electrical conductivity is also superior to that of steel belting and steel wire, enabling them to carry greater fault currents and ensure line safety.

[0036] The galvanized steel wire armor layer 24 protects the cable from external mechanical forces and damage. It also prevents rats and termites from gnawing at the armor, preventing problems with power transmission. It also ensures excellent bending and drag resistance. Furthermore, the galvanized steel wire armor layer 24 provides shielding, effectively shielding against electromagnetic interference. Its lightweight design and tightly woven galvanized steel wire armor layer 24 effectively preserve the cable's structural integrity and electrical performance, extending its service life.

[0037] The outermost layer of the cable is provided with a structure combining a nylon protective layer 26 and an outer sheath layer 25, which has both outer layer support and stress absorption capabilities, and can provide better protection and support for the internal structure of the cable during laying. The outer sheath layer 25 is made of PTFE Teflon polytetrafluoroethylene plastic, which makes the cable high temperature resistance level reach 250 degrees and low temperature resistance -60 degrees, and has excellent cold resistance, high temperature resistance, corrosion resistance, weather resistance, acid and alkali resistance, and environmental protection. The nylon material used in the nylon protective layer 26 has excellent wear resistance, cut resistance, oil resistance, corrosion resistance, heat resistance, high hardness and high lubricity, etc., which can withstand the gnawing of rodents and termites. The material is halogen-free and non-toxic, and is harmless to the soil and the surrounding environment when directly buried.

[0038] As a specific embodiment, the contacting sides of the nylon protective layer 26 and the outer jacket layer 25 are each formed with a plurality of interlocking interlocking portions 27. The interlocking portions 27 integrate the nylon protective layer 26 and the outer jacket layer 25 into a single unit, thereby improving the torsional resistance, support, and stress absorption capabilities of the outer layer structure and preventing breakage.

[0039] Furthermore, the outer periphery of the galvanized steel wire armor layer 24 is braided with a plurality of flared steel wires 241 circumferentially. A retaining hole 251 is formed on the side of the outer sheath layer 25 that contacts the galvanized steel wire armor layer 24 for receiving the flared steel wires 241. The bottom of the retaining hole 251 extends into the interlocking portion 27. Once the flared steel wires 241 are inserted into the retaining hole 251, the flared steel wires 241 and the interlocking portion 27 form a connected, integral unit.

[0040] Furthermore, the multiple outward-facing steel wires 241 and the interlocking portions 27 form a connected whole, through which a first connecting wire 28 is threaded, connecting the multiple units into a single braided whole. During processing, the first connecting wire 28 takes on a spiral shape and is threaded inside the outward-facing steel wires 241. This connects the outer galvanized steel wire armor layer 24, the outer sheath layer 25, and the nylon protective layer 26 into a single unit. The three maintain a stable relative position, preventing the outer sheath from becoming unthreaded during extended use, thereby ensuring the stability of the cable's internal protection.

[0041] During processing, the processing positions of the outward-stretched steel wire 241 and the first series-connected steel wire 28 are first positioned, and then the outer layer of the galvanized steel wire armor layer 24 is injection molded to ensure that the above-mentioned outward-stretched steel wire 241 and the first series-connected steel wire 28 support the structural strength of the entire cable.

[0042] As a specific embodiment, the inner circumference of the galvanized steel wire armor layer 24 is woven with a plurality of inward-spreading steel wires 242 in the circumferential direction through a weaving process. The PE sheath layer 23 is formed with an embedding hole 231 for the inward-spreading steel wire 242 to be embedded and installed. The inward-spreading steel wire 242 is embedded and installed in the bottom of the groove of the embedding hole 231. In addition, a second series steel wire 29 is also passed through the PE sheath layer 23. The second series steel wire 29 is spirally shaped and is passed through the inner side of the inward-spreading steel wire 242 when it is spirally shaped. In this way, the galvanized steel wire armor layer 24 and the PE sheath layer 23 are also connected into a whole. Through such a multi-layer structural whole, it can be ensured that the cable has stable rebound ability when subjected to strong torsion, is not easy to deform, is not easy to be derailed in a single layer, and has strong overall anti-pull ability. Whether it is buried or air-mounted, it has higher structural performance, does not break, and the ends are not easy to be derailed.

[0043] During processing, the processing positions of the inner expansion steel wire 242 and the second series-connected steel wire 29 are first positioned, and then the inner layer of the galvanized steel wire armor layer 24 is subjected to an injection molding process, thereby ensuring that the above-mentioned inner expansion steel wire 242 and the second series-connected steel wire 29 support the structural strength of the entire cable. As a specific embodiment, the two stripped ends of a smooth aluminum sheathed low-voltage cable 10 are both provided with a clamping ring 30 for clamping the two ends of the cable. The clamping ring 30 is provided with a fixing portion 301 for fixing to the position where the cable is connected. Specifically, the fixing portion 301 can be fixed to the position where the cable is connected by a screw, thereby improving the stability of the connection structure at the end of the cable, and further improving the safety of the cable during long-term use.

[0044] Furthermore, the clamping ring 30 is also provided with a connecting portion 302 for fixing the portions of the first series steel wire 28 and the second series steel wire 29 extending out of the cable. By fixing the ends of the first series steel wire 28 and the second series steel wire 29 extending out after the ends of the cable are stripped, the stability of the mechanical structure of the cable can be strengthened.

[0045] Specifically, the connecting portion 302 is formed with a self-locking rod 303 and a self-locking plug rod 304, which can self-lock the first and second series-connected steel wires 28 and 29. The self-locking plug rod 304 is detachably inserted into the insertion hole formed in the connecting portion 302, and the self-locking plug rod 304 is arranged parallel to the self-locking rod 303, so that they can be in parallel contact to tighten the ends of the steel wires as much as possible. When fixing the end of the first series steel wire 28 or the second series steel wire 29, the first series steel wire 28 or the second series steel wire 29 is wound along the overall periphery formed by the self-locking rod 303 and the self-locking plug rod 304, and the terminal is fixed in the connecting hole at one end of the self-locking plug rod 304, and then the self-locking plug rod 304 is pulled out in the opposite direction of the spiral winding of the first series steel wire 28 or the second series steel wire 29, so that the unwound end of the first series steel wire 28 or the second series steel wire 29 is locked by the part of itself that is wound, and the self-locking plug rod 304 locks the end of the first series steel wire 28 or the second series steel wire 29 to prevent it from falling off.

[0046] As an optional solution, the connecting portion 302 can be rotatably mounted on one side of the clamping ring 30 , which makes it easier to adjust the locking position of the end of the first serial steel wire 28 or the second serial steel wire 29 .

[0047] Furthermore, the spiral directions of the first series-connected steel wire 28 and the second series-connected steel wire 29 are opposite, so that when the cable receives an external force, the interior of the cable can be balanced through the opposite spiral torsional forces.

[0048] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the above embodiments do not limit the present invention in any form, and any technical solutions obtained by equivalent replacement or equivalent transformation fall within the scope of protection of the present invention.

Claims

1. A smooth aluminum sheathed low-voltage cable, characterized in that: include: Water-blocking aluminum conductor; The outer periphery of the water-blocking aluminum conductor is covered with a conductor shielding layer for fastening the water-blocking aluminum conductor to shield the water-blocking aluminum conductor; The outer periphery of the conductor shielding layer is covered with a polypropylene insulation layer for insulating the conductor; The outer periphery of the polypropylene insulation layer is coated with an insulation shielding layer for protecting the polypropylene insulation layer; The outer periphery of the insulating shielding layer is provided with a first semi-conductive water-swellable tape for improving waterproof performance; The outer periphery of the semi-conductive water-swellable tape is provided with a copper wire shielding layer for electrical shielding; The outer periphery of the copper wire shielding layer is wrapped with a tightening copper tape layer for tightening the copper wire shielding layer; The outer periphery of the tightening copper tape layer is coated with a second semi-conductive water-swellable tape for waterproofing the internal metal material; The outer periphery of the second semi-conductive water-swellable tape is provided with an aluminum-plastic composite tape layer for improving the structural strength and stress absorption capacity of the cable; The outer periphery of the aluminum-plastic composite tape layer is provided with a polymer sheath layer for buffering the torsional stress of the cable; An aluminum sheath layer is provided on the periphery of the polymer sheath layer for improving water-blocking performance; The outer periphery of the aluminum sheath layer is provided with a tape layer for further waterproofing; The outer periphery of the tape layer is provided with a PE sheath layer for protecting the internal structure of the cable; The outer periphery of the PE sheath layer is provided with a galvanized steel wire armor layer for improving the mechanical strength of the cable; The outer periphery of the galvanized steel wire armor layer is provided with an outer sheath layer for elastically supporting and protecting the galvanized steel wire armor layer; The outer periphery of the outer sheath layer is provided with a nylon protective layer for improving the dragging smoothness and support of the cable; The nylon protective layer and the outer sheath layer are both formed with a plurality of mutually engaging embedded parts on the sides that contact each other; The outer periphery of the galvanized steel wire armor layer is woven with a plurality of outward-stretching steel wires in the circumferential direction by a weaving process; The plurality of outwardly extending steel wires and the mutually embedded parts form a connected whole, through which a first connecting steel wire is passed for connecting the plurality of wholes in series into a braided whole; A second series steel wire is inserted into the PE sheath layer; Both stripped ends of the smooth aluminum sheathed low-voltage cable are sleeved with compression rings for compressing the two ends of the cable; The clamping ring is further provided with a connecting portion for fixedly connecting the portions of the first and second serially connected steel wires extending out of the cable; The connecting portion is formed with a self-locking rod and a self-locking insertion rod for self-locking the first and second series-connected steel wires.

2. A smooth aluminum sheathed low-voltage cable according to claim 1, characterized in that: A clamping hole for the outwardly extending steel wire to be clamped is formed on the side of the outer sheath layer that contacts the galvanized steel wire armor layer; The bottom of the clamping hole extends into the mutually embedded portion, so that the outward-stretching steel wire and the mutually embedded portion form a connected whole.

3. A smooth aluminum sheathed low-voltage cable according to claim 1, characterized in that: The first series connection steel wire is in a spiral shape and is passed through the inner side of the outward expansion steel wire when it is spiraled.

4. A smooth aluminum sheathed low-voltage cable according to claim 1, characterized in that: The inner periphery of the galvanized steel wire armor layer is circumferentially braided with a plurality of inwardly extending steel wires by a braiding process; The PE sheath layer is formed with an embedding hole for embedding and installing the inner expansion steel wire; The inwardly extending steel wire is embedded in the groove bottom of the embedding hole.

5. A smooth aluminum sheathed low-voltage cable according to claim 4, characterized in that: The second series-connected steel wire is in a spiral shape and is passed through the inner side of the inner-spreading steel wire when it is spiraled.

6. A smooth aluminum sheathed low-voltage cable according to claim 1, characterized in that: The clamping ring is provided with a fixing portion for fixing to a position where the cable is connected.

7. A smooth aluminum sheathed low-voltage cable according to claim 1, characterized in that: The self-locking rod is detachably inserted into the insertion hole formed on the connecting portion and is arranged parallel to the self-locking rod; The first series steel wire or the second series steel wire is wound along the entire periphery of the self-locking rod and the self-locking plug rod, and the terminal end is fixed in the connecting hole at one end of the self-locking plug rod; Pulling out the self-locking rod in a direction opposite to the spiral winding of the first series-connected steel wire or the second series-connected steel wire; The end of the first series-connected steel wire or the second series-connected steel wire is locked by the part wrapped around itself, and the self-locking plug-in rod locks the end of the first series-connected steel wire or the second series-connected steel wire to prevent it from falling off.

8. A smooth aluminum sheathed low-voltage cable according to claim 7, characterized in that: The spiral directions of the first series-connected steel wire and the second series-connected steel wire are opposite.

9. A smooth aluminum sheathed low-voltage cable according to claim 1, characterized in that: The inner side of the tightening copper tape layer is formed with a clamping foot for grasping the copper wires of the copper wire shielding layer; The copper tapes used to bind the copper tape layers are in a mesh structure with high mechanical ductility.

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