A B1 class flame-retardant low-voltage cable

Abstract

The utility model discloses a kind of B1-grade flame-retardant low-voltage cables, comprising: four conductor cores, four conductor cores outside are provided with insulation layer, four conductor cores are diagonally arranged, and the flame-retardant outer protective structure is provided outside four conductor cores;The flame-retardant outer protective structure includes: fixed band, filling layer, flame-retardant sheath layer, wrapping layer, metal armor layer and outer protective layer;The utility model relates to the technical field of flame-retardant low-voltage cable, the beneficial effect of the case is: solve the structure design in the existing flame-retardant power cable, due to internal insulation layer will occur certain softening effect after being heated, resulting in partial water molecules or hydrate in cable heat, can cause insulation layer to bulge and cause heat insulation layer to deform or break, and produce drop-down etc., resulting in the protective ability of cable is weak or make lose protection ability, the problem of poor use effect.

Description

Technical Field

[0001] This utility model relates to the field of flame-retardant low-voltage cable technology, specifically a B1-grade flame-retardant low-voltage cable. Background Technology

[0002] Flame-retardant low-voltage power cables are widely used in applications requiring high safety, environmental protection, and temperature resistance. They are halogen-free, low-smoke, flame-retardant, and temperature-resistant, providing safe and reliable power supply to high-rise buildings and residences, protecting residents' lives and property. They are also used in public places such as hospitals, schools, and shopping malls to provide power to facilities and ensure the normal operation of the power system in emergencies. However, in existing flame-retardant power cable designs, the internal insulation layer softens when heated, causing localized water molecules or hydrates in the cable to bulge, deform, or crack, and dripping. This weakens or eliminates the cable's protective capabilities, resulting in poor performance. Utility Model Content

[0003] To achieve the above objectives, this utility model is implemented through the following technical solution: a B1-grade flame-retardant low-voltage cable, comprising: four conductor cores, each of the four conductor cores having an insulation layer on its outer side, the four conductor cores being arranged diagonally, and the four conductor cores having a flame-retardant outer protective structure on their outer side.

[0004] The flame-retardant outer protective structure includes: a fixing strap, a filling layer, a flame-retardant sheath layer, a wrapping layer, a metal armor layer, and an outer protective layer;

[0005] The fixing strap is crisscrossed around the outside of the four conductor cores. A filling layer is provided in the gap between the fixing strap and the four conductor cores. The flame-retardant sheath layer is provided on the outer wall of the fixing strap. The wrapping layer is wrapped and fixed on the outer wall of the flame-retardant protective layer. The metal armor layer is provided on the outside of the flame-retardant sheath layer. The outer protective layer is extruded and wrapped around the outside of the metal armor layer.

[0006] Preferably, a reinforcing thin rod is embedded in the middle of the filling layer.

[0007] Preferably, the flame-retardant sheath layer has a double-layer structure, with a flame-retardant sheath on the outer side and a flame-retardant film pressed onto the inner side.

[0008] Preferably, the metal armor layer is composed of several woven galvanized sheets connected together.

[0009] Preferably, the fixing strap is secured using highly flame-retardant filler rope.

[0010] Preferably, the wrapping layer is wrapped using a fixed wrapping strap.

[0011] Beneficial effects

[0012] This utility model provides a B1-grade flame-retardant low-voltage cable with the following beneficial effects: This solution uses a flame-retardant outer protection structure, which includes multiple layers of protection such as a fixing tape, a filling layer, a flame-retardant sheath layer, a wrapping layer, a metal armor layer, and an outer protective layer. These layers work together to effectively prevent the spread of flames and the transfer of heat. In the event of a fire, it can significantly slow down the burning rate of the cable, reduce the danger and severity of the fire, buy valuable time for personnel evacuation and fire rescue, and greatly improve fire safety. Under fire conditions, the cable... The total heat release, peak heat release rate, total smoke production, smoke production rate, and combustion growth rate index during combustion are all very low, resulting in minimal impact on the surrounding environment. It is a truly safe cable, primarily used in subways, high-rise buildings, or densely populated areas. It solves the problem in existing flame-retardant power cable designs where the internal insulation layer softens upon heating, causing localized water molecules or hydrates in the cable to bulge, deform, or crack, and drip, thus weakening or eliminating the cable's protective capabilities and resulting in poor performance. Attached Figure Description

[0013] Figure 1 This is a three-dimensional structural diagram of a B1-grade flame-retardant low-voltage cable according to the present invention.

[0014] Figure 2 This is a side view of the structure of a B1-grade flame-retardant low-voltage cable according to the present invention.

[0015] Figure 3 This is a cross-sectional view of a B1-grade flame-retardant low-voltage cable according to the present invention.

[0016] In the diagram: 1-Conductor core; 2-Insulation layer; 3-Fixing tape; 4-Filling layer; 5-Flame-retardant sheath layer; 6-Wrapping layer; 7-Metal armor layer; 8-Outer protective layer; 9-Reinforcing rod; 10-Flame-retardant sheath; 11-Flame-retardant film. Detailed Implementation

[0017] Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0018] Example: Please refer to Figure 1-3A B1-grade flame-retardant low-voltage cable includes four conductor cores 1, each conductor core 1 has an insulation layer 2 on its outer side, the four conductor cores 1 are arranged neatly in a diagonal orientation, and a complete flame-retardant outer protection structure is constructed on the outer side of the four conductor cores 1, which includes, in sequence, a fixing wrapping tape 3, a filling layer 4, a flame-retardant sheath layer 5, a wrapping layer 6, a metal armor layer 7, and an outer protective layer 8;

[0019] Insulation layer 2 is wrapped around the outside of each conductor core 1, separating adjacent cores. Made of XLPE material, each core is individually wrapped for both separation and insulation. Fixing tape 3 is used to cross-wrap and secure the four conductor cores 1 wrapped with insulation layer 2. A filling layer 4 is pre-placed in the gap between the fixing tape 3 and the internal cores. The filling material is ceramicized silicone rubber with good elasticity and flame retardancy. Reinforcing rods 9, made of high-strength glass fiber reinforced plastic with a diameter of 2mm, are embedded in the filling layer 4 to enhance the cable's tensile strength. The gap surface between adjacent cores is calculated using AutoCAD. The area of ​​the gap is used to select the appropriate fixing tape and set the specifications of the filling layer 4. As the fixing tape 3 is wound into a preliminary cable, the filling layer 4 makes the core compact and round, reducing the gap in the cable core and reducing the oxygen content of the cable core. The flame-retardant sheath layer 5 has a double-layer structure. The outer flame-retardant sheath 10 uses low-voltage halogen-free flame-retardant polyolefin cable material. By adding inorganic flame retardants such as magnesium hydroxide and aluminum hydroxide, its flame-retardant ability and flame-retardant synergistic ability are improved. Its oxygen index is not less than 42. After a fire occurs, the hydroxide absorbs the heat from the outside and decomposes into water and metal oxides at high temperatures. This not only reduces the outside temperature, but the water produced can further cool down and eliminate outside oxygen. At the same time, the cable sheath can prevent fires. After the fire, the crust forms a heat-insulating layer with flame-retardant material to achieve heat insulation and oxygen isolation, which can further prevent the spread of flames, form a protective layer, prevent burning materials from dripping, and prevent further ignition of external combustibles. The flame-retardant film 11 pressed on the inner side is made of polyester flame-retardant film with a thickness of 0.1 mm. It is tightly bonded to the flame-retardant sheath 10 through a hot-pressing process to form a double flame-retardant barrier. Wrapping tape is used as the winding layer (6) and is wrapped and fixed to the outer wall of the flame-retardant sheath layer (5). The winding method is spiral winding to ensure tight winding and play a certain protective and fixing role. The metal armor layer 7 is made of several woven galvanized sheets connected together. Each galvanized sheet is woven with metal wires. The metal wires are 0.1 mm in diameter. The cable uses low-carbon galvanized steel wire, which is drawn and galvanized before being braided. This maintains high flexibility and tensile strength, increasing the overall strength of the cable. The outer protective layer is also made of low-voltage halogen-free flame-retardant polyolefin cable material, extruded and wrapped around the outside of the metal armor layer. This material is a high-molecular material that does not contain halogens (such as fluorine, chlorine, bromine, etc.) and heavy metals (such as lead, cadmium, chromium, mercury, etc.). It has low smoke, halogen-free, and flame-retardant properties. This material produces less smoke when burning and does not release toxic fumes. It has low corrosiveness and is less harmful to the environment and human body. It can withstand high operating temperatures and is suitable for various environmental conditions, effectively protecting the cable and preventing damage from environmental factors during use.

[0020] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A B1-grade flame-retardant low-voltage cable, characterized in that, include: Four conductor cores (1), each of the four conductor cores (1) is provided with an insulation layer (2) on the outside, the four conductor cores (1) are arranged diagonally, and the four conductor cores (1) are provided with a flame-retardant outer protective structure. The flame-retardant outer protective structure includes: a fixing strap (3), a filling layer (4), a flame-retardant sheath layer (5), a wrapping layer (6), a metal armor layer (7), and an outer protective layer (8); The fixing strap (3) is cross-wound around the outside of the four conductor cores (1). A filling layer (4) is provided in the gap between the fixing strap (3) and the four conductor cores (1). The flame-retardant sheath layer (5) is provided on the outer wall of the fixing strap (3). The wrapping layer (6) is wrapped and fixed on the outer wall of the flame-retardant sheath layer (5). The metal armor layer (7) is provided on the outside of the flame-retardant sheath layer (5). The outer protective layer (8) is extruded and wrapped around the outside of the metal armor layer (7).

2. The B1-grade flame-retardant low-voltage cable according to claim 1, characterized in that, The filling layer (4) has a reinforcing thin rod (9) embedded in the middle.

3. The B1-grade flame-retardant low-voltage cable according to claim 1, characterized in that, The flame-retardant sheath layer (5) has a double-layer structure, with a flame-retardant sheath (10) on the outside and a flame-retardant film (11) pressed onto the inside.

4. A B1-grade flame-retardant low-voltage cable according to claim 1, characterized in that, The metal armor layer (7) is composed of several woven galvanized sheets connected together.

5. A B1-grade flame-retardant low-voltage cable according to claim 1, characterized in that, The fixing strap (3) is secured by wrapping with highly flame-retardant filler rope.

6. A B1-grade flame-retardant low-voltage cable according to claim 1, characterized in that, The wrapping layer (6) is wrapped using a fixed wrapping strap.

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