Water-blocking wear-resistant cross-linked polyethylene insulated power cable

Abstract

The invention discloses a water-blocking wear-resistant crosslinked polyethylene insulated power cable, relates to the technical field of power cables, and solves the problems that a traditional power cable in the prior art is insufficient in environmental corrosion resistance, deteriorated in high-temperature working condition performance and poor in construction adaptability. Comprising an inner core, the inner core comprises a conductor layer, the conductor layer comprises a plurality of conductors distributed in an array extending mode, and each conductor is formed by compressing and twisting a plurality of strands of high-purity oxygen-free copper wires; the insulating layer is wrapped outside each conductor; the insulating layer sequentially comprises an inner insulating layer, a middle layer and an outer insulating layer, and the inner insulating layer wraps the outside of the semi-conductive water-blocking tape; the cable also comprises a sheath structure, and the sheath structure comprises a crosslinked polyethylene outer sheath. A functional layer; according to the cable scheme, external pressure can be effectively dispersed, local stress concentration is avoided, meanwhile, certain elastic buffering is provided, damage of impact to steel wires is reduced, and the cable is prevented from being deformed or damaged due to extrusion.

Description

Technical Field

[0001] This invention belongs to the field of power cable technology, and particularly relates to a water-blocking and wear-resistant cross-linked polyethylene insulated power cable. Background Technology

[0002] Power cables are a type of cable specifically designed for the transmission and distribution of electrical energy. They are widely used in urban underground power grid layouts, power plant lead-out lines, internal power supply systems in industrial and mining enterprises, and underwater power transmission projects across rivers and seas. Their basic structure comprises four core components: the conductor core, the insulation layer, the shielding layer, and the protective layer.

[0003] Currently, under complex operating conditions, traditional power cables exhibit the following technical deficiencies: (1) Insufficient resistance to environmental corrosion; In highly corrosive environments such as chemical and metallurgical industries, the cross-linked polyethylene outer sheath of cables is susceptible to corrosion by chemical media, leading to damage to the protective / functional layer and conductor oxidation, thereby shortening the cable's service life.

[0004] (2) Performance degradation under high-temperature conditions; In environments with sustained high temperatures (>90°C), the insulation material of ordinary cross-linked polyethylene (XLPE) cables undergoes thermal aging and embrittlement, resulting in a decrease in tear strength of more than 40%. Simultaneously, the metal shielding layer is prone to breakage during repeated bending and deformation.

[0005] (3) Poor construction adaptability Traditional cables have a relatively rigid structure, and additional compensation devices are required when laying them in narrow spaces or making sharp bends.

[0006] In summary, existing traditional power cables suffer from problems such as insufficient resistance to environmental corrosion, performance degradation under high-temperature conditions, and poor adaptability to construction. Summary of the Invention

[0007] This invention provides a water-blocking and wear-resistant cross-linked polyethylene insulated power cable, which can solve the problems of insufficient environmental corrosion resistance, performance degradation under high temperature conditions, and poor construction adaptability of traditional power cables in the prior art.

[0008] To achieve the above objectives, according to an embodiment of the first aspect of the present invention, a water-blocking and abrasion-resistant cross-linked polyethylene insulated power cable is provided, comprising an inner core, the inner core comprising: The conductor layer comprises a plurality of arrayed conductors, each conductor being formed by tightly twisting together multiple strands of high-purity oxygen-free copper wire; An insulating layer, wrapped around the outside of each conductor; The insulating layer comprises an inner insulating layer, an intermediate layer, and an outer insulating layer in sequence. The inner insulating layer is wrapped around the outside of the semiconducting resistive water tape. The outer insulating layer is wrapped with a polyester aluminized film by wrapping. An inner reinforcing layer is provided on the outside of the polyester aluminized film. Also includes: A sheath structure, the sheath structure comprising a cross-linked polyethylene outer sheath; A functional layer, wrapped around the outer side of the inner core and located inside the cross-linked polyethylene outer sheath, includes a pressure-resistant buffer layer, a water-blocking layer, and a heat dissipation layer. The heat dissipation layer includes a thermally conductive copper sleeve disposed outside the inner reinforcing layer and thermally conductive copper strips arrayed and fixedly installed outside the thermally conductive copper sleeve. Several buffer zones are formed between two adjacent thermally conductive copper strips and thermally conductive copper sleeves. The pressure-resistant buffer layer fills each buffer zone. The water-blocking layer is disposed outside the inner reinforcing layer and located inside the thermally conductive copper sleeve.

[0009] A further improvement is that the surface of the conductor is coated with a tin-plated layer, and a semiconducting resistive water tape is wrapped around the outside of the tin-plated layer.

[0010] A further improvement is that the inner reinforcing layer is made of soft copper strip braid.

[0011] A further improvement is that the pressure-resistant buffer layer is made of stainless steel wire and cross-linked polyethylene composite.

[0012] A further improvement is that the water-blocking layer is a water-blocking filler that fills the gaps in the soft copper strip wrapped in the inner reinforcing layer.

[0013] A further improvement is that the sheath structure also includes a glass fiber sleeve wrapped around the outside of the cross-linked polyethylene outer sheath and a silicone gasket disposed between the cross-linked polyethylene outer sheath and the glass fiber sleeve. The silicone gasket is bonded to the cross-linked polyethylene outer sheath and the glass fiber sleeve by a silane coupling agent.

[0014] A further improvement is that the functional layer also includes a silicone coating layer, which is coated on the surface of the glass fiber sleeve.

[0015] A further improvement is that the inner insulation layer is made of low-density cross-linked polyethylene, and the outer insulation layer is made of high-density cross-linked polyethylene.

[0016] A further improvement is that the outer side of the inner insulation layer and the inner wall of the outer insulation layer are both bonded to the intermediate layer by a silane coupling agent.

[0017] Compared with the prior art, the beneficial effects of the present invention are: (1) This invention designs an insulation layer consisting of an inner insulation layer, an intermediate layer, and an outer insulation layer. The inner insulation layer is made of low-density cross-linked polyethylene, and the outer insulation layer is made of high-density cross-linked polyethylene. The outer side of the inner insulation layer and the inner wall of the outer insulation layer are bonded to the intermediate layer by a silane coupling agent. The intermediate layer is made of glass fiber. This insulation layer is designed to withstand axial tensile force and inhibit the propagation of insulation layer cracks during bending, thereby improving the overall tensile strength of the insulation layer. In addition, a polyester aluminized film is wrapped around the outer insulation layer of the insulation layer. An inner reinforcing layer is provided on the outside of the polyester aluminized film. The inner reinforcing layer is woven from soft copper strip to improve the mechanical strength of the core. The polyester aluminized film can buffer external impacts and prevent scratches on the surface of the insulation layer. On the other hand, it can also be used as a shielding layer in conjunction with the inner reinforcing layer to ensure shielding and grounding, improve corrosion resistance and mechanical strength, further improve the electromagnetic interference effect, and ensure the signal output of the power cable. By coating the surface of each conductor in the inner core with a tin-plated layer, corrosion resistance can be enhanced. A semi-conductive resistive water tape is wrapped around the outside of the tin-plated layer. As a semi-conductive layer, it can uniformly distribute the electric field on the conductor surface and reduce local electric field concentration. On the other hand, it can form a longitudinal waterproof barrier as an inner waterproof layer to absorb mechanical stress and block water. When the cable comes into contact with water, it expands to block water penetration and avoid damage to the cable caused by water ingress, thereby protecting the internal conductor of the cable.

[0018] (2) This invention uses a sheath structure composed of a cross-linked polyethylene outer sheath, a glass fiber tube, and a silicone gasket as external protection. Since glass fiber itself is non-combustible, it can form a physical barrier to prevent the spread of flames and further isolate heat and oxygen. Moreover, the glass fiber tube can withstand a certain amount of external impact, preventing the cross-linked polyethylene outer sheath of the power cable from being flattened or scratched. It has high resistance to chemicals such as acids, alkalis, and salts and is not easily corroded, thereby extending the overall service life of the cable. The designed silicone gasket can absorb deformation when thermally expanded or compressed or subjected to mechanical extrusion, avoiding hard friction or local stress concentration between the glass fiber tube and the cross-linked polyethylene outer sheath, thereby preventing early thermal failure caused by mechanical damage. On the other hand, the silicone gasket can fill the gap between the glass fiber tube and the cross-linked polyethylene outer sheath, reducing thermal bridges or local hot spots and making the temperature distribution more uniform. In addition, a silicone coating layer is applied to the surface of the fiberglass sleeve. This coating layer is designed to maintain elasticity, preventing the fiberglass sleeve from cracking due to embrittlement and protecting the fiberglass from chemical corrosion, making it suitable for harsh environments such as chemical plants and marine environments. On the other hand, the silicone coating layer can reduce direct friction between the fiberglass and external objects, reducing the wear rate and extending the service life of the fiberglass sleeve. Furthermore, the silicone coating layer can absorb some impact energy, reducing the risk of breakage of the fiberglass sleeve, improving the fiberglass sleeve's resistance to mechanical damage, and preventing the fiberglass from becoming brittle due to photo-oxidative degradation.

[0019] (3) This invention designs a functional layer consisting of a pressure-resistant buffer layer, a water-blocking layer, a heat dissipation layer, and a silicone coating layer. The heat dissipation layer includes a heat-conducting copper sleeve disposed outside the inner reinforcement layer and heat-conducting copper strips arrayed and fixedly installed outside the heat-conducting copper sleeve. Several buffer zones are formed between adjacent heat-conducting copper strips and the heat-conducting copper sleeve. The pressure-resistant buffer layer fills each buffer zone, and the water-blocking layer is disposed outside the inner reinforcement layer and located inside the heat-conducting copper sleeve. The pressure-resistant buffer layer is made of stainless steel wire and cross-linked polyethylene. This design, on the one hand, utilizes the extremely high tensile strength and elastic modulus of stainless steel wire, which can effectively disperse external pressure and prevent the cable from deforming or being damaged by compression; while cross-linked polyethylene, as the matrix material, fills the gaps between the steel wires and fixes the position of the steel wires, avoiding local stress concentration and providing a certain elastic buffer to reduce impact damage to the steel wires; on the other hand, the support of the heat-conducting copper strips and the heat-conducting copper sleeve can compensate for excessive deformation when the steel wires are bent, preventing fatigue fracture after long-term bending of the cable; and can also protect the internal components of the cable. The heat dissipation prevents damage or spontaneous combustion of the cable's interior due to high temperatures, thus ensuring the cable's safety. Additionally, the water-blocking layer is a water-blocking filler that fills the gaps in the soft copper strip wrapping within the inner reinforcing layer. This design addresses two issues: firstly, if the cable or equipment experiences vibration, bending, or stretching during operation, the inner core may deform and create gaps. In this case, the water-blocking yarn can fill these gaps, maintaining water-blocking performance. Secondly, the water-blocking yarn can form a continuous double water-blocking protection with the polyester aluminized film, significantly improving the reliability of the power cable's water-blocking capability and extending the cable's service life. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the core and functional layer structure of the present invention; Figure 3 This is a schematic diagram of the functional layer and sheath layer structure of the present invention.

[0021] Marked in the image: 1. Inner core; 11. Conductor layer; 111. Conductor; 112. Semiconductor resistive water tape; 12. Insulation layer; 121. Inner insulation layer; 122. Intermediate layer; 123. Outer insulation layer; 13. Polyester aluminized film; 131. Inner reinforcement layer; 2. Functional layer; 21. Pressure-resistant buffer layer; 22. Water-blocking layer; 23. Heat dissipation layer; 231. Thermally conductive copper sleeve; 232. Thermally conductive copper strip; 233. Buffer zone; 24. Silicone coating layer; 3. Sheath structure; 31. Cross-linked polyethylene outer sheath; 32. Glass fiber sleeve; 33. Silicone gasket. Detailed Implementation

[0022] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. 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 3 As shown, a water-blocking and wear-resistant cross-linked polyethylene insulated power cable includes an inner core 1, which comprises: The conductor layer 11 includes a plurality of arrayed conductors 111, each conductor 111 being made of multiple strands of high-purity oxygen-free copper wire tightly twisted together, which can reduce contact resistance and improve mechanical strength. As a preferred embodiment, each conductor 111 is coated with a tin-plated layer to enhance corrosion resistance. A semi-conductive water-resistant tape 112 is wrapped around the outside of the tin-plated layer. As a semi-conductive layer, it can uniformly distribute the electric field on the surface of the conductor 111 and reduce local electric field concentration. On the other hand, it can form a longitudinal waterproof barrier as an inner waterproof layer to absorb mechanical stress and block water. When the cable comes into contact with water, it expands to block water penetration and avoid damage to the cable caused by water ingress, thereby protecting the internal conductor 111 of the cable. It should be noted that high-purity oxygen-free copper wire can be replaced with aluminum alloy to reduce resistance loss. Specifically, the inner core 1 also includes a layer of aluminized polyester film 13, which is wrapped around the outer insulation layer 123. An inner reinforcing layer 131 is provided on the outside of the aluminized polyester film 13. The inner reinforcing layer 131 is made of soft copper strip and is used to improve the mechanical strength of the inner core 1. On the one hand, the aluminized polyester film 13 can buffer external impacts and prevent scratches on the surface of the insulation layer 12. On the other hand, it can also be used as a shielding layer in conjunction with the inner reinforcing layer 131, which not only ensures shielding and grounding, but also improves corrosion resistance and mechanical strength, further improves the electromagnetic interference effect, and ensures the signal output of the power cable. An insulating layer 12 is wrapped around the outside of each conductor 111. The insulating layer 12 includes an inner insulating layer 121, an intermediate layer 122, and an outer insulating layer 123. The inner insulating layer 121 is wrapped around the outside of the semiconducting resistive water tape 112. The inner insulating layer 121 is made of low-density cross-linked polyethylene, and the outer insulating layer 123 is made of high-density cross-linked polyethylene. The outer side of the inner insulating layer 121 and the inner wall of the outer insulating layer 123 are bonded to the intermediate layer 122 by a silane coupling agent. The intermediate layer 122 is made of glass fiber. The design of the insulating layer 12 can withstand axial tensile force and inhibit the propagation of cracks in the insulating layer 12 when bent, thereby improving the overall tensile strength of the insulating layer 12. It should be noted that the material of the insulation layer 12 is extruded by a twin-screw extruder. The above is the structural improvement design of the inner core 1. The following section describes an improved design for the cable outer sheath; The cable includes a sheath structure 3, which comprises a cross-linked polyethylene outer sheath 31, a glass fiber sleeve 32 wrapped around the cross-linked polyethylene outer sheath 31, and a silicone gasket 33 disposed between the cross-linked polyethylene outer sheath 31 and the glass fiber sleeve 32. The silicone gasket 33 is bonded to the cross-linked polyethylene outer sheath 31 and the glass fiber sleeve 32 by a silane coupling agent. The glass fiber sleeve 32 is designed so that, because glass fiber itself is non-combustible, it can form a physical barrier to prevent the spread of flames and further isolate heat and oxygen. Moreover, the glass fiber sleeve 32 can withstand a certain amount of external impact, preventing the cross-linked polyethylene outer sheath 31 of the power cable from being flattened or scratched. It also has high resistance to chemicals such as acids, alkalis, and salts and is not easily corroded, thereby extending the overall service life of the cable. In this embodiment, the designed silicone gasket 33 can absorb deformation during thermal expansion and contraction or mechanical compression, preventing hard friction or localized stress concentration between the glass fiber sleeve 32 and the cross-linked polyethylene outer sheath 31, thereby preventing early thermal failure due to mechanical damage. On the other hand, the silicone gasket 33 can fill the gap between the glass fiber sleeve 32 and the cross-linked polyethylene outer sheath 31, reducing thermal bridges or localized hot spots and making the temperature distribution more uniform. Functional layer 2, which is wrapped around the outer side of inner core 1 and located inside cross-linked polyethylene outer sheath 31, includes a pressure-resistant buffer layer 21, a water-blocking layer 22, and a heat dissipation layer 23. The heat dissipation layer 23 includes a thermally conductive copper sleeve 231 disposed outside the inner reinforcing layer 131 and thermally conductive copper strips 232 arrayed and fixedly installed outside the thermally conductive copper sleeve 231. Several buffer zones 233 are formed between two adjacent thermally conductive copper strips 232 and thermally conductive copper sleeves 231. The pressure-resistant buffer layer 21 is filled in each buffer zone 233. The water-blocking layer 22 is disposed outside the inner reinforcing layer 131 and located inside the thermally conductive copper sleeve 231. The pressure-resistant buffer layer 21 is made of stainless steel wire and cross-linked polyethylene. This design is effective because stainless steel wire has extremely high tensile strength and elastic modulus, which can effectively disperse external pressure and prevent the cable from being deformed or damaged by compression. Cross-linked polyethylene, as the matrix material, fills the gaps between the steel wires and fixes their positions, avoiding local stress concentration and providing a certain degree of elastic buffer to reduce impact damage to the steel wires. On the other hand, the support of the thermally conductive copper strip 232 can compensate for excessive deformation of the steel wires when bending, preventing fatigue fracture of the cable after long-term bending. The water-blocking layer 22 is a layer of water-blocking filler that fills the gaps in the soft copper strip wrapping in the inner reinforcing layer 131. This design has two advantages: firstly, if the cable or equipment experiences vibration, bending, or stretching during operation, the inner core 1 may develop gaps due to mechanical deformation. In this case, the water-blocking yarn can fill the deformation gaps and maintain the water-blocking performance; secondly, the water-blocking yarn can form a continuous double water-blocking protection with the polyester aluminized film 13, which significantly improves the reliability of the power cable's water blocking and thus extends the cable's service life. In this embodiment, there is also a preferred implementation where the functional layer 2 further includes a silicone coating layer 24. The silicone coating layer 24 is coated on the surface of the glass fiber sleeve 32. The design of this coating layer can, on the one hand, maintain elasticity, prevent the glass fiber sleeve 32 from cracking due to embrittlement, and protect the glass fiber from chemical corrosion, making it suitable for harsh environments such as chemical plants and marine environments; on the other hand, the silicone coating layer 24 can reduce direct friction between the glass fiber and external objects, reduce the wear rate, and extend the service life of the glass fiber sleeve 32; furthermore, the silicone coating layer 24 can absorb some impact energy, reduce the risk of glass fiber breakage, improve the glass fiber sleeve 32's resistance to mechanical damage, and prevent the glass fiber sleeve 32 from becoming brittle due to photo-oxidative degradation.

[0024] In this embodiment, it should also be noted that the power cable in the application document is manufactured according to existing production processes and is considered prior art. Furthermore, it should be noted that this application document only addresses the shortcomings of traditional power cables in the prior art, such as insufficient resistance to environmental corrosion, performance degradation under high-temperature conditions, and poor construction adaptability; it does not involve improvements in other aspects. In practical applications, the power cable design of this invention is improved and upgraded by separately modifying the inner core 1 and the outer sheath structure of the cable, as follows: By coating the surface of each conductor 111 in the inner core 1 with a tin-plated layer, corrosion resistance can be enhanced. A semi-conductive water-resistant tape 112 is wrapped around the outside of the tin-plated layer. As a semi-conductive layer, it can uniformly distribute the electric field on the surface of the conductor 111 and reduce local electric field concentration. On the other hand, it can form a longitudinal waterproof barrier as an inner waterproof layer to absorb mechanical stress and block water. When the cable comes into contact with water, it expands to block water penetration and avoid damage to the cable caused by water ingress, thereby protecting the inner conductor 111 of the cable. The insulation layer 12 is designed to consist of an inner insulation layer 121, an intermediate layer 122, and an outer insulation layer 123. The inner insulation layer 121 is made of low-density cross-linked polyethylene, and the outer insulation layer 123 is made of high-density cross-linked polyethylene. The outer side of the inner insulation layer 121 and the inner wall of the outer insulation layer 123 are bonded to the intermediate layer 122 by a silane coupling agent. The intermediate layer 122 is made of glass fiber. The design of this insulation layer 12 can withstand axial tensile force and inhibit the propagation of cracks in the insulation layer 12 when bent, thereby improving the overall tensile strength of the insulation layer 12. In addition, a polyester aluminized film 13 is wrapped around the outer insulation layer 123 of the insulation layer 12. An inner reinforcing layer 131 is provided on the outside of the polyester aluminized film 13. The inner reinforcing layer 131 is made of soft copper strip and is used to improve the mechanical strength of the inner core 1. On the one hand, the polyester aluminized film 13 can buffer external impacts and prevent scratches on the surface of the insulation layer 12. On the other hand, it can also be used as a shielding layer in conjunction with the inner reinforcing layer 131, which not only ensures shielding and grounding, but also improves corrosion resistance and mechanical strength, further improves the electromagnetic interference effect, and ensures the signal output of the power cable.

[0025] The sheath structure 3, composed of a cross-linked polyethylene outer sheath 31, a fiberglass sleeve 32, and a silicone gasket 33, serves as external protection. Because fiberglass itself is non-combustible, it forms a physical barrier to prevent the spread of flames and further isolates heat and oxygen. Furthermore, the fiberglass sleeve 32 can withstand certain external impacts, preventing the cross-linked polyethylene outer sheath 31 from being flattened or scratched. It also exhibits high resistance to acids, alkalis, salts, and other chemicals, making it less susceptible to corrosion and thus extending the overall service life of the cable. The designed silicone gasket 33, on the one hand, absorbs deformation during thermal expansion and contraction or mechanical compression, preventing hard friction or localized stress concentration between the fiberglass sleeve 32 and the cross-linked polyethylene outer sheath 31, thereby preventing early thermal failure due to mechanical damage. On the other hand, the silicone gasket 33 fills the gap between the fiberglass sleeve 32 and the cross-linked polyethylene outer sheath 31, reducing thermal bridges or localized hot spots and resulting in a more uniform temperature distribution. In addition, the silicone coating layer 24 is applied to the surface of the glass fiber sleeve 32. This coating layer is designed to maintain elasticity, prevent the glass fiber sleeve 32 from cracking due to embrittlement, and protect the glass fiber from chemical corrosion, making it suitable for harsh environments such as chemical plants and marine environments. On the other hand, the silicone coating layer 24 can reduce direct friction between the glass fiber and external objects, reduce the wear rate, and extend the service life of the glass fiber sleeve 32. Furthermore, the silicone coating layer 24 can absorb some impact energy, reduce the risk of breakage of the glass fiber sleeve 32, improve the glass fiber sleeve 32's resistance to mechanical damage, and prevent the glass fiber from becoming brittle due to photo-oxidative degradation.

[0026] The design incorporates a functional layer 2 consisting of a pressure-resistant buffer layer 21, a water-blocking layer 22, a heat dissipation layer 23, and a silicone coating layer 24. The heat dissipation layer 23 includes a thermally conductive copper sleeve 231 disposed outside the inner reinforcing layer 131 and thermally conductive copper strips 232 arrayed and fixedly mounted outside the thermally conductive copper sleeve 231. Several buffer zones 233 are formed between adjacent thermally conductive copper strips 232 and the thermally conductive copper sleeve 231. The pressure-resistant buffer layer 21 fills each buffer zone 233. The water-blocking layer 22 is disposed outside the inner reinforcing layer 131 and located inside the thermally conductive copper sleeve 231. Its pressure-resistant buffer layer 21 is made of stainless steel wire and cross-linked polyethylene. This design, on the one hand, utilizes the extremely high tensile strength and elastic modulus of stainless steel wire to effectively disperse external pressure and prevent cable deformation or damage due to compression; while cross-linked polyethylene, as the matrix material, fills the gaps between the steel wires and fixes their position, avoiding localized stress concentration and providing a certain degree of elastic buffering to reduce impact damage to the steel wires; on the other hand, the support of the thermally conductive copper strip 232 and the thermally conductive copper sleeve 231 can both compensate for excessive deformation during steel wire bending, preventing fatigue fracture after long-term bending of the cable; and also protect the internal structure of the cable. The heat dissipation prevents damage or spontaneous combustion of the cable due to high temperatures, thus ensuring the safety of cable use. In addition, the water-blocking layer 22 is a water-blocking filler that fills the gaps in the soft copper tape wrapping in the inner reinforcing layer 131. This design has two advantages: firstly, if the cable or equipment experiences vibration, bending, or stretching during operation, the inner core 1 may develop gaps due to mechanical deformation. In this case, the water-blocking yarn can fill the deformation gaps and maintain the water-blocking performance; secondly, the water-blocking yarn can form a continuous double water-blocking protection with the polyester aluminized film 13, which significantly improves the reliability of water blocking in power cables and thus extends the service life of cables.

[0027] The above embodiments are only used to illustrate the technical methods of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical methods of the present invention without departing from the spirit and scope of the technical methods of the present invention.

Claims

1. A water-blocking wear-resistant cross-linked polyethylene insulated power cable, comprising an inner core (1), the inner core (1) comprising: a conductor layer (11) comprising a plurality of array-extended distributed conductors (111), each conductor (111) being tightly stranded by a plurality of high-purity oxygen-free copper wires; an insulation layer (12) wrapped outside each conductor (111); characterized in that the insulation layer (12) comprises, in sequence, an inner insulation layer (121), an intermediate layer (122) and an outer insulation layer (123), the inner insulation layer (121) being wrapped outside a semi-conductive water-blocking tape (112), and an outer surface of the outer insulation layer (123) being wrapped with a polyester aluminum-plated film (13) by wrapping, and an outer surface of the polyester aluminum-plated film (13) being provided with an inner reinforcing layer (131); further comprising: a sheath structure (3) comprising a cross-linked polyethylene outer sheath (31); a functional layer (2) wrapped outside the inner core (1) and inside the cross-linked polyethylene outer sheath (31), the functional layer (2) comprising a pressure-resistant buffer layer (21), a water-blocking layer (22) and a heat dissipation layer (23), the heat dissipation layer (23) comprising a heat-conducting copper sleeve (231) provided outside the inner reinforcing layer (131) and a plurality of array-extended heat-conducting copper strips (232) fixedly installed outside the heat-conducting copper sleeve (231), a plurality of buffer zones (233) being formed between adjacent two heat-conducting copper strips (232) and the heat-conducting copper sleeve (231), the pressure-resistant buffer layer (21) being filled in each buffer zone (233), and the water-blocking layer (22) being provided outside the inner reinforcing layer (131) and inside the heat-conducting copper sleeve (231).

2. A water-blocking, wear-resistant, crosslinked polyethylene insulated power cable according to claim 1, characterized in that, A tinning layer is coated on a surface of the conductor (111), and the semi-conductive water-blocking tape (112) is wrapped outside the tinning layer by wrapping.

3. A water-blocking, wear-resistant crosslinked polyethylene insulated power cable according to claim 1, characterized in that, The inner reinforcing layer (131) is woven by soft copper strips.

4. A water-blocking, wear-resistant crosslinked polyethylene insulated power cable according to claim 1, characterized in that, The pressure-resistant buffer layer (21) is compounded by stainless steel wires and cross-linked polyethylene.

5. A water-blocking, wear-resistant crosslinked polyethylene insulated power cable according to claim 1, characterized in that, The water-blocking layer (22) is a layer of water-blocking filler filled in gaps wrapped by the soft copper strips in the inner reinforcing layer (131).

6. A water-blocking, wear-resistant crosslinked polyethylene insulated power cable according to claim 1, characterized in that, The sheath structure (3) further comprises a glass fiber sleeve (32) wrapped outside the cross-linked polyethylene outer sheath (31) and a silica gel gasket (33) provided between the cross-linked polyethylene outer sheath (31) and the glass fiber sleeve (32), and the silica gel gasket (33) is adhered to the cross-linked polyethylene outer sheath (31) and the glass fiber sleeve (32) by a silane coupling agent.

7. A water-blocking, wear-resistant, crosslinked polyethylene insulated power cable according to claim 6, characterized in that The functional layer (2) further comprises a silica gel coating layer (24) coated on a surface of the glass fiber sleeve (32).

8. A water-blocking, wear-resistant crosslinked polyethylene insulated power cable according to claim 1, characterized in that, The inner insulation layer (121) is made of low-density cross-linked polyethylene material, and the outer insulation layer (123) is made of high-density cross-linked polyethylene material.

9. A water-blocking, wear-resistant crosslinked polyethylene insulated power cable according to claim 8, characterized in that, The inner insulation layer (121) and the outer insulation layer (123) are adhered to the intermediate layer (122) by a silane coupling agent.

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