A low-smoke halogen-free cable

Abstract

This utility model discloses a low-smoke halogen-free cable, comprising a conductor, an outer polyethylene layer, an inner aluminum-plastic composite strip, and an outer aluminum-plastic composite strip. The thickness of the inner aluminum-plastic composite strip is less than that of the outer aluminum-plastic composite strip. An ethylene-vinyl acetate copolymer layer is disposed outside the outer aluminum-plastic composite strip. A mica tape is wound around the ethylene-vinyl acetate copolymer layer. A halogen-free, low-smoke, flame-retardant polyolefin layer is disposed outside the mica tape. This utility model has the following advantages and effects: through a gradient functional layer synergistic design, it achieves a breakthrough improvement in fire safety and mechanical reliability. In the event of a fire, it avoids the release of toxic hydrogen halide gas, reduces smoke generation, and reduces threats to life safety and the environment.

Description

Technical Field

[0001] This utility model relates to the field of cable technology, and in particular to a low-smoke halogen-free cable. Background Technology

[0002] A cable is a device for transmitting electrical energy or signals, typically composed of several or groups of conductors. Each group of conductors is insulated from each other and is often twisted around a central conductor, with the entire cable covered by a highly insulating outer layer. Cables are characterized by being internally energized and externally insulated.

[0003] With the increasing demands for fire safety and environmental protection in modern society, the application of traditional halogenated flame retardant materials is gradually being restricted because they release large amounts of toxic hydrogen halide gas and produce dense smoke during combustion, posing a serious threat to life safety and the environment. Utility Model Content

[0004] The purpose of this invention is to provide a low-smoke, halogen-free cable.

[0005] The above-mentioned technical objective of this utility model is achieved through the following technical solution: a low-smoke halogen-free cable, comprising a conductor, a polyethylene layer disposed outside the conductor, an inner aluminum-plastic composite strip disposed outside the polyethylene layer, an outer aluminum-plastic composite strip disposed outside the inner aluminum-plastic composite strip, the thickness of the inner aluminum-plastic composite strip being less than the thickness of the outer aluminum-plastic composite strip; an ethylene-vinyl acetate copolymer layer disposed outside the outer aluminum-plastic composite strip, a mica tape wound around the ethylene-vinyl acetate copolymer layer, and a halogen-free low-smoke flame-retardant polyolefin layer disposed outside the mica tape.

[0006] The inner aluminum-plastic composite strip has a thickness of 0.08 mm, and the outer aluminum-plastic composite strip has a thickness of 0.15 mm.

[0007] The inner aluminum-plastic composite strip and the outer aluminum-plastic composite strip are further configured such that the coverage rate in the width direction is between 15% and 20%.

[0008] A further configuration is provided: a silica aerogel felt layer is provided outside the mica strip.

[0009] In summary, this utility model has the following beneficial effects: This patent achieves a breakthrough improvement in fire safety and mechanical reliability through a gradient functional layer synergistic design: 1. The double aluminum-plastic composite strips of different thicknesses maintain electromagnetic shielding effectiveness, while the inner aluminum-plastic composite strip reduces the bending radius and improves dynamic bending life, and the outer aluminum-plastic composite strip provides compressive strength gain; 2. The fusion-ceramization synergistic effect formed between the ethylene-vinyl acetate copolymer layer and the mica strip allows the ethylene-vinyl acetate copolymer to melt and fill the micro-gaps in the mica layer at high temperatures, promoting the formation of a dense barrier, while also isolating oxygen diffusion and extending the fire resistance time. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of the cross-sectional structure of a low-smoke halogen-free cable.

[0011] In the diagram: 1. Conductor; 2. Polyethylene layer; 3. Inner aluminum-plastic composite tape; 4. Outer aluminum-plastic composite tape; 5. Ethylene-vinyl acetate copolymer layer; 6. Mica tape; 7. Halogen-free low-smoke flame-retardant polyolefin layer; 8. Silica aerogel felt layer. Detailed Implementation

[0012] The present invention will be further described in detail below with reference to the accompanying drawings.

[0013] A low-smoke, halogen-free cable comprising the innermost conductor 1.

[0014] A polyethylene layer 2 is provided on the outside of the conductor 1. The polyethylene layer 2 serves as an insulating layer to isolate the conductor 1 from the outside.

[0015] An inner aluminum-plastic composite strip 3 is wound around the polyethylene layer 2. The coverage of the inner aluminum-plastic composite strip 3 in the width direction is between 15% and 20%, thus maintaining its stability. The thickness of the inner aluminum-plastic composite strip 3 is 0.08 mm.

[0016] An outer aluminum-plastic composite strip 4 is wound around the inner aluminum-plastic composite strip 3. The coverage of the outer aluminum-plastic composite strip 4 in the width direction is the same as that of the inner aluminum-plastic composite strip 3, which is also between 15% and 20%. However, the thickness of the outer aluminum-plastic composite strip 4 is 0.15mm.

[0017] The inner aluminum-plastic composite tape 3 and the outer aluminum-plastic composite tape 4 serve as shielding layers. They work together to ensure the shielding effect while allowing the inner aluminum-plastic composite tape 3 to fit more tightly against the polyethylene outer layer. It is also less prone to wrinkles or cracks when the cable is bent, making it easier to bend the cable compared to traditional aluminum-plastic composite tapes. Meanwhile, the outer aluminum-plastic composite tape 4 has improved compressive strength, effectively resisting mechanical damage such as trampling and squeezing during installation.

[0018] An ethylene-vinyl acetate copolymer layer 5 is disposed on the outer side of the outer aluminum-plastic composite strip 4. The ethylene-vinyl acetate copolymer layer 5 contains 12-18% VA to achieve insulation and to achieve a balance between flexibility and strength. This content of ethylene-vinyl acetate copolymer is existing technology.

[0019] Mica tape 6 is wound around the ethylene-vinyl acetate copolymer layer 5. Mica tape 6 is a commonly used fireproof material in the cable industry.

[0020] A halogen-free, low-smoke, flame-retardant polyolefin layer 7 is provided outside the mica strip 6. This halogen-free, low-smoke, flame-retardant polyolefin layer 7 is also a commonly used fireproof material in the field, and it exists as the outermost protective sleeve.

[0021] Preferably, a silica aerogel felt layer 8 is disposed between the mica tape 6 and the halogen-free, low-smoke, flame-retardant polyolefin layer 7. This silica aerogel felt layer 8 has a thickness of 0.1 mm and possesses excellent thermal insulation properties, remaining stable even at high temperatures without sintering, deformation, or settling. This structure provides thermal insulation both internally and externally, thereby reducing the burning rate of the cable in the event of a fire and increasing safety.

[0022] This specific embodiment is merely an explanation of the present utility model and is not intended to limit the present utility model. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but as long as they are within the scope of the claims of the present utility model, they are protected by patent law.

Claims

1. A low-smoke, halogen-free cable, characterized in that: The device includes a conductor, an outer polyethylene layer, an inner aluminum-plastic composite strip, and an outer aluminum-plastic composite strip. The thickness of the inner aluminum-plastic composite strip is less than that of the outer aluminum-plastic composite strip. An ethylene-vinyl acetate copolymer layer is disposed on the outer side of the outer aluminum-plastic composite strip. A mica tape is wound around the ethylene-vinyl acetate copolymer layer. A halogen-free, low-smoke, flame-retardant polyolefin layer is disposed on the outer side of the mica tape.

2. The low-smoke halogen-free cable according to claim 1, characterized in that: The inner aluminum-plastic composite strip has a thickness of 0.08 mm, and the outer aluminum-plastic composite strip has a thickness of 0.15 mm.

3. The low-smoke halogen-free cable according to claim 1, characterized in that: The coverage of both the inner and outer aluminum-plastic composite strips in the width direction is between 15% and 20%.

4. The low-smoke halogen-free cable according to claim 1, characterized in that: A silica aerogel felt layer is provided on the outside of the mica strip.

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