A polyolefin sheathed power cable

Abstract

This utility model discloses a polyolefin-sheathed power cable, relating to the field of power cable technology. It includes a cable core comprising a conductor, an insulation layer covering the conductor, and a shielding layer covering the insulation layer. A buffer layer is disposed outside the cable core, and a reinforcing layer is disposed outside the buffer layer. A polyolefin sheath is disposed outside the reinforcing layer. The polyolefin sheath includes an inner antioxidant polyolefin layer and an outer flame-retardant polyolefin layer, with the flame-retardant polyolefin layer coated outside the antioxidant polyolefin layer. This solution solves the problems of insufficient performance, poor insulation, and inadequate shielding of existing power cable sheaths.

Description

Technical Field

[0001] This utility model relates to the field of power cable technology, specifically to a polyolefin sheathed power cable. Background Technology

[0002] Polyolefin sheathed power cables, with their excellent comprehensive performance, occupy a pivotal position in the modern power transmission field. From a working principle perspective, polyolefin sheathed power cables achieve efficient power transmission through conductors. The insulation layer effectively isolates the conductor from the external environment, preventing current leakage and ensuring electrical safety. The shielding layer reduces electromagnetic interference, ensuring stable power signal transmission. The polyolefin sheath provides physical protection for the cable, resisting external mechanical damage, chemical corrosion, and environmental erosion. With the rapid development of the power industry, the performance requirements for cables are constantly increasing.

[0003] For example, the Chinese authorized patent CN209496657U, entitled "A Power Cable," includes several cable units. Each cable unit is surrounded by a wrapping tape, and a filler tape is placed between the wrapping tape and the cable units. An inner sheath, an armor layer, and an outer sheath are sequentially arranged outside the wrapping tape. Each cable unit includes several cores, and a metal outer shell is placed outside the cores. XLPE insulation material is placed between the metal outer shell and the cores. An insulating shielding layer and a metal shielding layer are sequentially arranged outside the metal outer shell. Optimizing the structure of the power cable improves its mechanical properties and electrical stability.

[0004] In practical applications, the polyolefin sheaths of some cables have poor anti-aging properties and are prone to cracking and hardening when exposed to sunlight, rain, and other environments for a long time, resulting in the loss of protection for the internal structure of the cable. The insulation performance of the insulation layer will significantly decrease in high temperature and humid environments, affecting the stability of power transmission. The shielding layer has poor shielding effect in complex electromagnetic environments and is difficult to meet the requirements of modern electronic equipment-intensive environments for cable anti-interference capabilities. Therefore, it does not meet the current needs. In response, we propose a polyolefin sheathed power cable. Utility Model Content

[0005] The purpose of this utility model is to provide a polyolefin-sheathed power cable to solve the problems of insufficient sheath performance, poor insulation and shielding effect of existing power cables mentioned in the background art.

[0006] To achieve the above objectives, this utility model provides the following technical solution: a polyolefin sheathed power cable, comprising a cable core, the cable core comprising a conductor, an insulation layer covering the conductor, and a shielding layer covering the insulation layer, a buffer layer disposed outside the cable core, a reinforcing layer disposed outside the buffer layer, and a polyolefin sheath disposed outside the reinforcing layer, the polyolefin sheath comprising an inner antioxidant polyolefin layer and an outer flame-retardant polyolefin layer, wherein the flame-retardant polyolefin layer is coated outside the antioxidant polyolefin layer.

[0007] Preferably, the conductor is made of multiple strands of tin-plated copper wire twisted together, and the surface of the conductor is treated with anti-oxidation.

[0008] Preferably, the insulating layer is based on cross-linked polyethylene, with added nano-silica and flame retardant, and is coated onto the surface of the conductor by an extrusion process.

[0009] Preferably, the shielding layer includes an inner aluminum foil shielding layer and an outer copper wire braided shielding layer. The aluminum foil shielding layer is wrapped around the insulating layer by a wrapping process, and the copper wire braided shielding layer is woven around the aluminum foil shielding layer.

[0010] Preferably, the buffer layer is made of EVA foam material and is formed into a continuous elastic layer using a foaming process.

[0011] Preferably, the reinforcing layer is a glass fiber reinforced polyamide composite material, which is formed into a tubular structure by a pultrusion process and wrapped around the outside of the buffer layer.

[0012] Preferably, the cable core has a flat structure, with circular structures on both sides of the flat structure in cross-section and a rectangular structure at the connection point.

[0013] Compared with the prior art, the beneficial effects of this utility model are:

[0014] 1. The polyolefin sheath of this utility model is composed of an antioxidant polyolefin layer and a flame-retardant polyolefin layer. The antioxidant polyolefin layer can effectively resist the oxidation of the cable by factors such as ultraviolet rays and oxygen, extending the service life of the cable; the flame-retardant polyolefin layer has good flame-retardant properties, which can effectively prevent the spread of flames and reduce fire losses when the cable is in fire. At the same time, it does not release toxic and harmful gases when burning, making it more environmentally friendly and safe.

[0015] 2. The conductor of this utility model is made of multi-strand tin-plated copper wire twisted together and subjected to anti-oxidation treatment, which reduces the conductor resistance, improves the conductivity efficiency, enhances the conductor's anti-oxidation and anti-corrosion ability, and ensures that the cable's conductivity is stable and reliable during long-term use.

[0016] 3. The insulation layer of this utility model uses cross-linked polyethylene as the base material and adds nano-silica and flame retardant, which has excellent electrical insulation performance, mechanical strength and flame retardant performance; the shielding layer adopts a combination of aluminum foil shielding layer and copper wire braided shielding layer to achieve effective shielding against electromagnetic interference of different frequencies, ensure uniform electric field distribution and improve the stability and safety of cable operation.

[0017] 4. The EVA foam material of the buffer layer and the glass fiber reinforced polyamide composite material of the reinforcing layer of this utility model work together to give the cable good impact resistance and mechanical strength, enabling it to adapt to various complex operating environments, protect the internal structure of the cable, and extend the overall service life of the cable. Attached Figure Description

[0018] Figure 1 This is a perspective view of the present utility model;

[0019] Figure 2 This is a schematic diagram of the internal structure of the present invention;

[0020] Figure 3 This is a schematic diagram of the shielding layer structure of this utility model;

[0021] Figure 4 This is a schematic diagram of the polyolefin sheath structure of this utility model.

[0022] In the diagram: 1. Cable core; 2. Conductor; 3. Insulation layer; 4. Shielding layer; 41. Aluminum foil shielding layer; 42. Copper wire braided shielding layer; 5. Buffer layer; 6. Reinforcing layer; 7. Polyolefin sheath; 71. Antioxidant polyolefin layer; 72. Flame retardant polyolefin layer. Detailed Implementation

[0023] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments.

[0024] Please see Figure 1-4 The present invention provides an embodiment of a polyolefin sheathed power cable, comprising a cable core 1, the cable core 1 comprising a conductor 2, an insulation layer 3 covering the conductor, and a shielding layer 4 covering the insulation layer 3. A buffer layer 5 is provided outside the cable core 1, a reinforcing layer 6 is provided outside the buffer layer 5, and a polyolefin sheath 7 is provided outside the reinforcing layer 6. The polyolefin sheath 7 comprises an inner antioxidant polyolefin layer 71 and an outer flame-retardant polyolefin layer 72, and the flame-retardant polyolefin layer 72 is coated on the outside of the antioxidant polyolefin layer 71.

[0025] Each layer works together to enhance the overall performance of the cable. The cable core 1 is responsible for power transmission, the buffer layer 5 and the reinforcing layer 6 provide mechanical protection for the cable, and the polyolefin sheath 7 ensures the long-term stable operation of the cable from both anti-oxidation and flame-retardant perspectives, extending the cable's service life and improving the safety of power transmission.

[0026] Please see Figure 1 and Figure 2 Conductor 2 is made of multiple strands of tin-plated copper wire, and the surface of conductor 2 is treated with anti-oxidation. The multiple strands of tin-plated copper wire improve the flexibility of the cable, making it easier to lay the cable in complex environments. Tin plating enhances the conductor's anti-oxidation ability, reduces resistance, and improves conductivity. The surface anti-oxidation treatment further extends the service life of the conductor, ensuring that the cable's conductivity is stable and reliable during long-term use.

[0027] Furthermore, the insulation layer 3 uses cross-linked polyethylene as the base material, with added nano-silica and flame retardants, and is coated onto the surface of the conductor 2 through an extrusion process. Cross-linked polyethylene has excellent electrical insulation and mechanical properties, and the addition of nano-silica enhances the wear resistance and mechanical strength of the insulation layer, making it less prone to wear and damage. The addition of flame retardants gives the insulation layer good flame retardant properties, which can effectively prevent the spread of fire in the event of an accident, and comprehensively ensure the safety of cable operation.

[0028] Please see Figure 3 The shielding layer 4 includes an inner aluminum foil shielding layer 41 and an outer copper wire braided shielding layer 42. The aluminum foil shielding layer 41 is wrapped around the insulation layer 3 by a wrapping process, and the copper wire braided shielding layer 42 is woven around the aluminum foil shielding layer 41. The aluminum foil shielding layer 41 can effectively shield low-frequency electromagnetic interference, while the copper wire braided shielding layer 42 has a good shielding effect on high-frequency electromagnetic interference. The combination of the two achieves comprehensive shielding against electromagnetic interference of different frequencies, ensuring uniform electric field distribution, enabling the cable to stably transmit power signals even in complex electromagnetic environments, and reducing interference to surrounding electronic equipment.

[0029] Furthermore, the buffer layer 5 is made of EVA foam material, which is formed into a continuous elastic layer using a foaming process. EVA foam material has good elasticity and buffering performance. When the cable is subjected to external impact, it can quickly absorb and disperse the impact force, effectively protecting the cable core, insulation layer and other key structures inside the cable from damage. At the same time, its lightweight and soft characteristics will not add too much weight to the cable, nor will it affect the cable's flexibility, making it easy for the cable to be installed and used.

[0030] Furthermore, the reinforcing layer 6 is a glass fiber reinforced polyamide composite material, which is made into a tubular structure by pultrusion and wrapped around the outside of the buffer layer 5. The glass fiber reinforced polyamide composite material has high strength, high rigidity and good corrosion resistance, which can provide reliable mechanical support for the cable and effectively resist external pressure, tension and torsional force; even in complex and harsh environments, it can ensure the structural stability and integrity of the cable and extend the overall service life of the cable.

[0031] Furthermore, cable core 1 has a flat structure with circular sides and a rectangular connection in cross-section. In terms of installation, the flat shape offers strong conformability, making it easier to lay in narrow spaces, corners, and cable trays compared to traditional round cables. It also facilitates the parallel installation of multiple cables, ensuring a tight fit and minimizing the risk of rolling or shifting, thus maximizing the use of limited space. Regarding heat dissipation, the flat structure increases the cable's contact area with air, and the design connecting the circular sides to the central rectangle allows for smoother airflow over the cable surface, accelerating heat dissipation. This structure also optimizes cable flexibility, reducing the risk of internal structural damage during bending and adapting to various complex installation environments.

[0032] Working principle: First, multiple strands of tin-plated copper wire are twisted together to form conductor 2, and the surface of conductor 2 is treated with anti-oxidation. Then, cross-linked polyethylene is used as the base material, and nano-silica and flame retardant are added. It is then extruded to cover the conductor surface to form insulation layer 3. Subsequently, aluminum foil shielding layer 41 is wrapped around insulation layer 3 using a wrapping process. Copper wire is then braided into shielding layer and woven around aluminum foil shielding layer 41 to form complete shielding layer 4. Afterward, EVA foam material is made into a continuous elastic layer as buffer layer 5 using a foaming process and wrapped around cable core 1. Then, glass fiber reinforced polyamide composite material is made into a tubular structure using a pultrusion process and wrapped around buffer layer 5 to form reinforcement layer 6. Finally, the inner layer of anti-oxidation polyolefin material is formed by extrusion process, and the outer layer of flame retardant polyolefin material is coated on its outer surface to form polyolefin sheath 7, which is wrapped around reinforcement layer 6, thus completing the processing of polyolefin sheathed power cable.

[0033] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A polyolefin sheathed power cable, comprising a cable core (1), characterized in that: The cable core (1) includes a conductor (2), an insulation layer (3) covering the conductor, and a shielding layer (4) covering the insulation layer (3). A buffer layer (5) is provided on the outside of the cable core (1). A reinforcing layer (6) is provided on the outside of the buffer layer (5). A polyolefin sheath (7) is provided on the outside of the reinforcing layer (6). The polyolefin sheath (7) includes an inner antioxidant polyolefin layer (71) and an outer flame-retardant polyolefin layer (72), and the flame-retardant polyolefin layer (72) is coated on the outside of the antioxidant polyolefin layer (71).

2. The polyolefin-sheathed power cable according to claim 1, characterized in that: The conductor (2) is made of multiple strands of tin-plated copper wire twisted together, and the surface of the conductor (2) is treated with anti-oxidation.

3. The polyolefin-sheathed power cable according to claim 1, characterized in that: The insulating layer (3) is coated on the surface of the conductor (2) by an extrusion process.

4. The polyolefin-sheathed power cable according to claim 1, characterized in that: The shielding layer (4) includes an inner aluminum foil shielding layer (41) and an outer copper wire braided shielding layer (42). The aluminum foil shielding layer (41) is wrapped around the insulation layer (3) by a wrapping process, and the copper wire braided shielding layer (42) is woven around the aluminum foil shielding layer (41).

5. A polyolefin-sheathed power cable according to claim 1, characterized in that: The buffer layer (5) is made of EVA foam material and is formed into a continuous elastic layer using a foaming process.

6. A polyolefin-sheathed power cable according to claim 1, characterized in that: The reinforcing layer (6) is a glass fiber reinforced polyamide composite material, which is made into a tubular structure by pultrusion process and wrapped around the outside of the buffer layer (5).

7. A polyolefin-sheathed power cable according to claim 1, characterized in that: The cable core (1) has a flat structure, with circular structures on both sides of the flat structure in cross-section and a rectangular structure at the connection.

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