Fireproof heat insulation type tensile medium-voltage cable

Abstract

The utility model discloses a fireproof heat insulation type tensile medium voltage cable, comprising a cable core, the cable core comprises a wire core, the wire core is composed of an inner sheath and a conductor, the inner sheath is composed of an inner insulating layer, semiconductor paper and a copper strip, the cable core is wrapped by a composite fireproof layer, and the composite fireproof layer is wrapped by an outer insulating layer. The composite fireproof layer is composed of a heat insulation layer, an isolation layer and a fire retardant layer, the composite fireproof layer is wrapped by a composite tensile layer, the composite tensile layer is composed of a base layer, an enhancement layer and a protection layer, and through the mode, the problem that the medium-voltage cable is poor in fireproof, heat insulation and tensile performance is solved.

Description

Technical Field

[0001] The utility model relates to the technical field of medium-voltage cables, in particular to a fireproof, heat-insulating, tensile-resistant medium-voltage cable. Background Art

[0002] Medium voltage cable refers to power cables with rated voltage between 1kV-35kV, which are mainly used for power transmission and distribution at medium current or medium voltage level. It plays an important role in connecting substations and distribution networks in the power system, and undertakes the important tasks of energy transmission and signal transmission. The structure of medium voltage cable usually includes conductor, insulation layer, conductor shielding layer, insulation layer cable core, metal sheath, metal sheath, outer sheath and other parts. These components together ensure the electrical performance, mechanical performance and environmental adaptability of the cable.

[0003] For example, the Chinese authorized patent "A Medium Voltage Cable" with announcement number CN206893347U includes a conductor, an inner shielding layer, an insulating layer, an outer shielding layer and a protective layer. The inner shielding layer is coated on the conductor, the insulating layer is coated on the inner shielding layer, the outer shielding layer is coated on the insulating layer, and the protective layer is coated on the outer shielding layer. The conductor includes multiple fan-shaped parts, and the multiple fan-shaped parts form a ring structure. The conductor is composed of multiple fan-shaped parts, has good flexibility, and is convenient for cable laying. Multiple fan-shaped parts are directly in contact to form a conductor.

[0004] In actual use, although the above-mentioned prior art can provide a certain tensile strength, as the working temperature increases and under the influence of fire conditions, the overall strength and tensile strength will decrease significantly, thereby affecting the transmission performance of the cable. Therefore, it does not meet the existing needs. In this regard, we propose a fire-proof and heat-insulating tensile medium-voltage cable. Utility Model Content

[0005] The utility model aims to provide a fireproof heat-insulating tensile-resistant medium-voltage cable to solve the problem of poor fireproof heat-insulating and tensile-resistant performance of the medium-voltage cable mentioned in the above background technology.

[0006] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a fireproof, heat-insulating, tensile-resistant medium-voltage cable, comprising a cable core, the cable core comprising a wire core, the wire core consisting of an inner sheath and a conductor, wherein the inner sheath consists of an inner insulating layer, a semiconductor paper and a copper tape, the outside of the cable core is wrapped with a composite fireproof layer, the composite fireproof layer consists of a heat-insulating layer, an isolation layer and a fire-blocking layer, the outside of the composite fireproof layer is wrapped with a composite tensile-resistant layer, and the composite tensile-resistant layer consists of a base layer, a reinforcement layer and a protective layer.

[0007] Preferably, the gap between the cable core and the wire core is filled with filler.

[0008] Preferably, the semiconductor paper and the copper tape constitute an inner shielding layer of the conductor, the semiconductor paper is wrapped on the outer wall of the inner insulating layer, and the copper tape is wound on the outside of the semiconductor paper.

[0009] Preferably, the heat insulation layer is wound on the outer wall of the cable core, the isolation layer is arranged on the outer wall of the heat insulation layer, and the fire barrier layer is filled between the isolation layer and the composite tensile layer.

[0010] Preferably, the base layer is woven in a mesh shape and wrapped around the outside of the composite fireproof layer, the reinforcement layer is evenly distributed along the length direction of the cable, the protective layer is located outside the reinforcement layer, and the protective layer and the reinforcement layer are extruded.

[0011] Preferably, the inner insulating layer is made of cross-linked polyethylene.

[0012] Preferably, the base layer braiding angle is controlled between 25-50°.

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

[0014] 1. The utility model forms the inner shielding layer of the core by combining semiconductor paper and copper tape on the inner sheath of the core. Semiconductor paper is a paper material with semiconductor properties, and its resistivity is between that of a conductor and an insulator. Semiconductor paper can balance the electric field distribution inside the cable, reduce partial discharge, and improve the electrical performance of the cable. The copper tape is on the outside of the semiconductor paper. The copper tape has good conductivity and ductility, which can further enhance the electromagnetic shielding effect of the cable and improve the mechanical strength of the cable.

[0015] 2. The utility model is provided with a composite fireproof layer. The inner ceramic armor fireproof mica tape has extremely high fireproof performance. Its efficiency can be increased by more than 60% compared with ordinary fireproof mica tape. It can effectively prevent the spread of fire in a fire and ensure the safety of the cable. The outer ceramic armor is filled with oxygen-insulating mud, which also has excellent fireproof performance. After burning, it gradually ceramicizes to form a hard ceramic armor shell that can withstand spraying and vibration. The middle layer uses a high oxygen index oxygen-insulating layer with an oxygen index of more than 38, which means that the cable has extremely low oxygen content when burning without an external combustion source, that is, it has excellent anti-combustion performance. This helps to limit the spread of fire when a fire occurs and reduce property losses and casualties.

[0016] 3. The utility model has excellent tensile properties through the combination design of composite tensile layer, basic tensile layer and reinforcement layer. The addition of metal belt further improves the tensile strength and ductility of the cable, making it difficult for the cable to break or deform when subjected to tension. The setting of the protective layer makes the cable have good wear resistance and corrosion resistance. This can not only protect the internal layer from erosion and damage by the external environment, but also extend the service life of the cable. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is an overall three-dimensional diagram of the utility model;

[0018] Figure 2 It is a schematic diagram of the overall internal structure of the utility model;

[0019] Figure 3 This is a schematic diagram of the composite fireproof layer structure of the utility model;

[0020] Figure 4 It is a schematic diagram of the composite tensile layer structure of the utility model.

[0021] In the figure: 1, cable core; 2, wire core; 21, inner sheath; 211, inner insulation layer; 212, semiconductor paper; 213, copper tape; 22, conductor; 3, filler; 4, composite fireproof layer; 41, thermal insulation layer; 42, isolation layer; 43, fire barrier layer; 5, composite tensile layer; 51, base layer; 52, reinforcement layer; 53, protective layer. DETAILED DESCRIPTION

[0022] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments.

[0023] See also Figure 1-4 The utility model provides an embodiment: a fireproof heat-insulating tensile-resistant medium-voltage cable, comprising a cable core 1, the cable core 1 comprising a wire core 2, the wire core 2 consisting of an inner sheath 21 and a conductor 22, wherein the inner sheath 21 consists of an inner insulating layer 211, a semiconductor paper 212 and a copper tape 213, the outside of the cable core 1 is wrapped with a composite fireproof layer 4, the composite fireproof layer 4 consists of a heat-insulating layer 41, an isolation layer 42 and a fire-blocking layer 43, the outside of the composite fireproof layer 4 is wrapped with a composite tensile-resistant layer 5, the composite tensile-resistant layer 5 consists of a base layer 51, a reinforcement layer 52 and a protective layer 53.

[0024] This fireproof and heat-insulating tensile medium-voltage cable adopts lightweight and high-strength materials, multi-layer shielding structure and special fireproof and heat-insulating design, which successfully solves the problems of traditional cables in weight, construction difficulty, electrical performance, fireproof and heat-insulating performance, environmental safety and mechanical strength, providing a more advanced, reliable and environmentally friendly solution for the field of power transmission.

[0025] See also Figure 1 and Figure 2 The gap between the cable core 1 and the wire core 2 is filled with a filler 3, and the filler 3 is alkali-free glass fiber yarn filling, which serves as a filling material to enhance the structural stability and mechanical strength of the cable.

[0026] See also Figure 2 The semiconductor paper 212 and the copper tape 213 constitute the inner shielding layer of the conductor 22. The semiconductor paper 212 is wrapped on the outer wall of the inner insulating layer 211, and the copper tape 213 is wrapped on the outside of the semiconductor paper 212. The inner shielding layer can effectively reduce the influence of electromagnetic interference on the internal electrical performance of the cable, ensure the stable operation of the cable, and provide certain insulation protection to prevent the internal electrical parameters of the cable from being affected by the external environment. The combination of the copper tape 213 and the semiconductor paper 212 makes the inner shielding layer have both good conductivity and certain insulation performance, thereby ensuring the stability of the electrical performance of the cable.

[0027] See also Figure 3 The heat insulation layer 41 is wound on the outer wall of the cable core 1, the isolation layer 42 is arranged on the outer wall of the heat insulation layer 41, and the fire barrier layer 43 is filled between the isolation layer 42 and the composite tensile layer 5. The heat insulation layer 41 is a ceramic armor fireproof and fire-resistant mica tape, which provides fireproof and heat-insulating protection for the cable; the isolation layer 42 is a high oxygen index oxygen-insulating layer with an oxygen index of more than 38, which effectively isolates oxygen and improves the fireproof performance of the cable; the fire barrier layer 43 is a ceramic armor filled with oxygen-insulating mud, which further improves the fireproof and heat-insulating performance of the cable. Compared with the wrapped mica tape, the longitudinally wrapped ceramic mica tape can greatly reduce the cost, because the wrapping thickness plus the overlap rate is much thicker than the thickness of the ceramic mica tape, and the wrapping speed is lower than the longitudinal wrapping speed of the ceramic mica tape, plus the time efficiency, labor and water and electricity costs, etc., make the cost of ordinary and synthetic mica tapes much higher than that of the ceramic mica tape;

[0028] The cable fireproof layer, which is composed of an inner layer of ceramic armor fireproof and fire-resistant mica tape, a middle layer of high oxygen index oxygen insulation layer with an oxygen index of more than 38, and an outer layer of ceramic armor filled with oxygen insulation mud, has multiple effects such as high efficiency fire prevention, high oxygen index oxygen insulation, cost reduction, excellent insulation and heat insulation performance, and environmental protection and safety, providing a strong guarantee for the safe operation of the cable.

[0029] See also Figure 4The base layer 51 is woven in a mesh shape and wrapped on the outside of the composite fireproof layer 4. The reinforcement layer 52 is evenly distributed along the length direction of the cable. The protective layer 53 is located outside the reinforcement layer 52, and the protective layer 53 and the reinforcement layer 52 are extruded. The base layer 51 is made of glass fiber and woven in a mesh shape. It has the characteristics of light weight and high strength, can effectively resist tension, and reduce the overall weight of the cable; the reinforcement layer 52 is made of copper alloy, and multiple layers of copper alloy strips are added and evenly distributed along the length direction of the cable to further enhance the tensile performance; the protective layer 53 is made of polyvinyl chloride, which has good physical and chemical stability and can protect the inner layer from damage by the external environment;

[0030] The design of the composite tensile layer enables the cable to be lightweight while maintaining high strength. The use of lightweight and high-strength materials makes the cable more stable and reliable when subjected to tension, while reducing the overall weight of the cable, making it easier to install and transport.

[0031] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-restrictive from any point of view, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention. Any reference numeral in a claim should not be regarded as limiting the claim to which it relates.

Claims

1. A fireproof and heat-insulating tensile medium voltage cable, comprising a cable core (1), characterized in that: The cable core (1) comprises a wire core (2), wherein the wire core (2) is composed of an inner sheath (21) and a conductor (22), wherein the inner sheath (21) is composed of an inner insulating layer (211), a semiconductor paper (212) and a copper tape (213); the outside of the cable core (1) is wrapped with a composite fireproof layer (4), wherein the composite fireproof layer (4) is composed of a heat insulation layer (41), an isolation layer (42) and a fire barrier layer (43); the outside of the composite fireproof layer (4) is wrapped with a composite tensile layer (5), wherein the composite tensile layer (5) is composed of a base layer (51), a reinforcement layer (52) and a protective layer (53).

2. A fireproof and heat-insulated tensile medium voltage cable according to claim 1, characterized in that: The gap between the cable core (1) and the wire core (2) is filled with a filler (3).

3. A fireproof and heat-insulated tensile medium voltage cable according to claim 1, characterized in that: The semiconductor paper (212) and the copper tape (213) constitute an inner shielding layer of the conductor (22); the semiconductor paper (212) is wrapped around the outer wall of the inner insulating layer (211); and the copper tape (213) is wound around the outside of the semiconductor paper (212).

4. A fireproof and heat-insulated tensile medium voltage cable according to claim 1, characterized in that: The heat insulation layer (41) is wound on the outer wall of the cable core (1), the isolation layer (42) is arranged on the outer wall of the heat insulation layer (41), and the fire barrier layer (43) is filled between the isolation layer (42) and the composite tensile layer (5).

5. The fireproof and heat-insulating tensile medium voltage cable according to claim 1, characterized in that: The base layer (51) is woven in a mesh shape and wrapped around the outside of the composite fireproof layer (4); the reinforcement layer (52) is evenly distributed along the length direction of the cable; the protective layer (53) is located outside the reinforcement layer (52); and the protective layer (53) and the reinforcement layer (52) are extruded.

6. The fireproof and heat-insulated tensile medium voltage cable according to claim 1, characterized in that: The inner insulating layer (211) is made of cross-linked polyethylene.

7. The fireproof and heat-insulating tensile medium voltage cable according to claim 5, characterized in that: The braiding angle of the base layer (51) is controlled between 25-50°.

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