Halogen-free low-smoke low-toxicity flame-retardant fireproof power cable
By adopting a composite wrapping structure in halogen-free, low-smoke, low-toxicity, flame-retardant, and fire-resistant cables, and combining a multi-layer wrapping design with mica tape and glass fiber tape, the problems of insufficient toughness and high-temperature resistance of existing cables are solved, achieving better overall performance and adaptability, and extending the service life of the cables.
Patent Information
- Application Number
- CN202520288194.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-23
- Publication Date
- 2025-12-30
- Estimated Expiration
- 2035-02-23
AI Technical Summary
The existing cabling and wrapping structures of halogen-free, low-smoke, low-toxicity, flame-retardant, and fire-resistant cables have problems with poor toughness and insufficient high-temperature resistance. In particular, the mica tape wrapping is prone to breakage, and the glass fiber tape wrapping has poor isolation properties.
The cable adopts a composite wrapping structure, combining a multi-layer wrapping design of mica tape and fiberglass tape. The inner layer is mica tape wrapping, the middle layer is fiberglass tape wrapping, and the outer layer can be copper foil tape wrapping, forming a multi-layer wrapping structure that enhances the cable's toughness and high-temperature resistance. The overall performance is further improved by filling with alkali-free glass fiber and using a halogen-free, low-smoke, flame-retardant polyolefin sheath.
While ensuring high-temperature resistance, the cable's toughness and anti-aging ability have been improved, extending its service life. The wrapping ratio has been adjusted according to different working conditions to enhance adaptability and improve the cable's performance under extreme conditions such as fires.
Smart Images
Figure CN223743325U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of power cable technology, and more specifically to halogen-free, low-smoke, low-toxicity, flame-retardant, and fire-resistant power cables. Background Technology
[0002] Traditional power cables often use halogen-containing materials for insulation or sheathing, which burn rapidly in a fire and release large amounts of toxic fumes. This not only exacerbates the spread of fire but also greatly hinders evacuation and rescue efforts. Therefore, existing technologies use halogen-free, low-smoke, low-toxicity, flame-retardant Class A fire-resistant power cables as a replacement. These cables use halogen-free materials for insulation and sheathing, producing less smoke and lower toxicity during combustion, thus improving the chances of escape and the efficiency of firefighting and rescue operations.
[0003] Currently, halogen-free, low-smoke, low-toxicity, flame-retardant, and fire-resistant cables are usually wrapped with mica tape or fiberglass tape. The wrapping structure determines the insulation capability of the inner and outer layers of the cable. Mica tape wrapping can provide better insulation and high-temperature resistance, but it has poor toughness and is easy to break. Fiberglass tape wrapping has lower high-temperature resistance and poorer insulation than mica tape. Utility Model Content
[0004] To address the technical problems existing in halogen-free, low-smoke, low-toxicity, flame-retardant power cables in the prior art, this utility model proposes a halogen-free, low-smoke, low-toxicity, flame-retardant, fire-resistant power cable, comprising:
[0005] Multiple wire cores arranged tangentially in pairs;
[0006] A flame-retardant filling structure is disposed between two adjacent wire cores;
[0007] A composite wrapping structure is used to wrap around the outside of the wire core and the flame-retardant filling structure, forming a cable core with a circular cross-section.
[0008] The inner sheath is extruded onto the outer wall of the composite wrapping structure;
[0009] An armor layer that covers the outer wall of the inner sheath;
[0010] A flame-retardant layer is wrapped around the outer wall of the armor layer;
[0011] The outer sheath is extruded onto the outer wall of the flame-retardant layer;
[0012] The composite wrapping structure includes a multi-layer wrapping structure, including at least a mica tape wrapping structure layer and a glass ribbon wrapping structure layer. The composite wrapping structure includes a three-layer wrapping structure, wherein the inner wrapping structure includes a mica tape wrapping structure layer, the middle wrapping structure includes a glass ribbon wrapping structure layer, and the outer wrapping structure includes a mica tape wrapping structure layer or a copper foil tape wrapping structure layer.
[0013] As an optional embodiment, the copper foil wrapping structure layer includes a double copper foil wrapping layer, wherein the inner copper foil wrapping layer is wound in the same direction as the middle wrapping structure, and the outer copper foil wrapping layer is wound in the opposite direction to the inner copper foil wrapping layer.
[0014] As an optional embodiment, the wrapping overlap rate of the mica tape wrapping structure layer is 25-35%, and the wrapping overlap rate of the glass ribbon is 20-25%.
[0015] As an optional embodiment, the wrapping angle of the mica tape wrapping structure layer and the glass tape wrapping structure layer is 30-40°, and the wrapping direction is the same.
[0016] As an optional embodiment, the wire core includes a stranded copper conductor, a phlogopite tape wrapping layer wrapped around the outer wall of the stranded copper conductor, and a cross-linked polyethylene insulation layer extruded around the outer wall of the phlogopite tape wrapping layer.
[0017] As an optional embodiment, the phlogopite tape wrapping layer includes right-side overlapping phlogopite tape with a wrapping overlap rate of greater than or equal to 20%.
[0018] As an optional embodiment, the flame-retardant filling structure includes alkali-free glass fiber filling rope.
[0019] As an optional embodiment, the armor layer includes a double-layer galvanized steel strip wrapping layer, each galvanized steel strip having a gap wrapping structure, and the outer galvanized steel strip overlapping the gap outside the inner galvanized steel strip.
[0020] As an optional embodiment, the flame-retardant layer includes an alkali-free glass fiber tape wrapping layer, and the outer sheath includes a halogen-free low-smoke flame-retardant polyolefin sheath layer.
[0021] Compared with existing technologies, the significant advantages of this halogen-free, low-smoke, low-toxicity, flame-retardant, and fire-resistant power cable are as follows:
[0022] The halogen-free, low-smoke, low-toxicity, flame-retardant, and fire-resistant power cable proposed in this utility model transforms the existing single glass ribbon and mica tape wrapping structures into a composite wrapping structure of glass ribbon and mica tape. This allows the cable wrapping structure to combine the advantages of both glass ribbon and mica tape wrapping structures, ensuring high-temperature resistance while also possessing good toughness and anti-aging capabilities. This extends the service life under extreme conditions such as fires. Furthermore, the wrapping ratio of the two can be flexibly adjusted according to different working conditions, making the product more adaptable. Attached Figure Description
[0023] The accompanying drawings are not intended to be drawn to scale. In the drawings, each identical or nearly identical component shown in the various figures may be denoted by the same reference numeral. For clarity, not every component is labeled in each figure. Embodiments of various aspects of the present invention will now be described by way of example and with reference to the accompanying drawings, wherein:
[0024] Figure 1 This is a schematic diagram of the structure of the halogen-free, low-smoke, low-toxicity, flame-retardant, and fire-resistant power cable shown in this utility model.
[0025] Figure 2 This is a schematic diagram of the cross-sectional structure of the halogen-free, low-smoke, low-toxicity, flame-retardant, and fire-resistant power cable shown in this utility model. Detailed Implementation
[0026] To better understand the technical content of this utility model, specific embodiments are provided below in conjunction with the accompanying drawings.
[0027] Combination Figure 1 and Figure 2 As shown, this utility model proposes a halogen-free, low-smoke, low-toxicity, flame-retardant, and fire-resistant power cable, comprising a conductor 1, a flame-retardant filling structure 2, a composite wrapping structure 3, an inner sheath 4, an armor layer 5, a flame-retardant layer 6, and an outer sheath 7.
[0028] The cable core contains multiple tangentially arranged cores 1, and a flame-retardant filling structure 2 is placed between two adjacent cores 1, making the cable core structure compact and fixed into a circular cross-section.
[0029] Optionally, the conductor 1 includes a stranded copper conductor 11, a phlogopite tape wrapping layer 12 wrapped around the outer wall of the stranded copper conductor 11, and a cross-linked polyethylene insulation layer 13 extruded around the outer wall of the phlogopite tape wrapping layer 12.
[0030] The stranded copper conductor 11 is a type 2 stranded compacted copper conductor, and the phlogopite tape wrapping layer 12 preferably uses two layers of right-hand overlapping phlogopite tape with a thickness of 0.14 mm and a wrapping overlap rate of greater than or equal to 20%.
[0031] In this way, the phlogopite tape isolates the stranded copper conductor 11 from the external environment, reduces high-temperature oxidation and arc damage, and extends the cable life. The cross-linked structure of the cross-linked polyethylene insulation layer 13 is not easily softened at high temperatures, and can maintain its insulation performance, meeting the requirements of flame retardant, low-smoke and halogen-free applications in the fields of construction, power, and communications.
[0032] In an optional embodiment, the flame-retardant filling structure 2 is made of alkali-free glass fiber filling rope. The alkali-free glass fiber filling rope is woven from alkali-free glass fiber into a rope shape, which has good tensile strength. It is filled between multiple wire cores 1 to provide flame-retardant capability for the wire cores 1, and to prevent external heat or flame from being transferred to the wire cores 1 or to the open flame caused by a short circuit in the wire cores 1 from being transferred to other wire cores and the outside.
[0033] Furthermore, the composite wrapping structure 3 covers the outside of the wire core 1 and the flame-retardant filling structure 2, forming a cable core with a circular cross-section. The inner sheath 4 is extruded onto the outer wall of the composite wrapping structure 3, and the inner sheath 4 includes a halogen-free, low-smoke, flame-retardant polyolefin oxygen barrier layer. The composite wrapping structure 3 forms an isolation between the wire core 1 and the inner sheath 4.
[0034] Among them, the composite wrapping structure 3 includes a multi-layer wrapping structure, including at least a mica tape wrapping structure layer and a glass ribbon wrapping structure layer.
[0035] Mica tape has excellent high-temperature resistance and can maintain good insulation performance in high-temperature environments. Although glass fiber tape has slightly inferior high-temperature resistance to mica tape, its good toughness can compensate for the brittleness of mica tape at high temperatures. Therefore, by using a multi-layer wrapping structure, especially the combination of mica tape wrapping layer and glass fiber tape wrapping layer, the advantages of both can be combined to provide better overall performance in high-temperature environments.
[0036] In addition, since glass fiber tape has better anti-aging properties than mica tape, the composite wrapping structure can slow down the aging process of the material and extend the overall service life of the cable.
[0037] In an optional embodiment, the overlap rate of the mica tape wrapping structure layer is 25-35%, and the overlap rate of the glass fiber tape wrapping structure layer is 20-25%. The wrapping angle of the mica tape wrapping structure layer and the glass fiber tape wrapping structure layer is 30-40°, and the wrapping direction is the same. This increases the wrapping speed of the wrapping layer and makes the structure compact.
[0038] In optional embodiments, the composite wrapping structure can be adjusted according to the needs of specific application scenarios. For example, in high-temperature environments, the proportion of mica tape can be increased, i.e., a structure of mica tape wrapping structure layer + glass ribbon wrapping structure layer + mica tape wrapping structure layer; in applications requiring higher toughness, the proportion of glass ribbon can be increased, i.e., a structure of glass ribbon wrapping structure layer + mica tape wrapping structure layer + glass ribbon wrapping structure layer.
[0039] Furthermore, in environments with higher electromagnetic shielding requirements, the composite wrapping structure 3 can be selected as a three-layer wrapping structure, wherein the inner wrapping structure 31 includes a mica tape wrapping structure layer, the middle wrapping structure 32 includes a glass ribbon wrapping structure layer, and the outer wrapping structure 33 includes a copper foil tape wrapping structure layer.
[0040] Thus, by adding a copper foil wrapping layer, the shielding effect of the cable is enhanced. At the same time, the copper foil itself has a higher melting point, which makes the cable's performance more stable in high-temperature environments and reduces local overheating.
[0041] In an optional embodiment, the copper foil wrapping structure layer includes a double copper foil wrapping layer, wherein the inner copper foil wrapping layer is wound in the same direction as the middle wrapping structure 32, and the outer copper foil wrapping layer is wound in the opposite direction to the inner copper foil wrapping layer.
[0042] This gives the copper foil wrapping layer high strength and toughness, effectively enhancing the overall mechanical properties of the cable and reducing the risk of damage caused by external forces (such as tension, bending, impact, etc.).
[0043] Furthermore, the armor layer 5 covers the outer wall of the inner sheath 4. The armor layer 5 includes a double-layer galvanized steel strip wrapping layer, each galvanized steel strip having a gap wrapping structure, and the outer galvanized steel strip overlapping the gap outside the inner galvanized steel strip.
[0044] The mechanical properties of cables can be further improved by wrapping them with galvanized steel strips, especially their resistance to pressure and external impact.
[0045] like Figure 2 As shown, the flame retardant layer 6 covers the outer wall of the armor layer 5, and the outer sheath 7 is extruded onto the outer wall of the flame retardant layer 6; wherein, the flame retardant layer 6 includes an alkali-free glass fiber tape wrapping layer, and the outer sheath 7 includes a halogen-free low-smoke flame retardant polyolefin sheath layer.
[0046] Thus, the alkali-free glass fiber tape wrapping layer together with the inner sheath 4 forms an oxygen-barrier structure, which prevents external air from entering the cable's interior when it catches fire.
[0047] In conjunction with the above embodiments, this utility model designs the existing single glass ribbon wrapping structure and mica tape wrapping structure into a composite wrapping structure of glass ribbon and mica tape. This allows the cabling wrapping structure to combine the advantages of both glass ribbon and mica tape wrapping structures. While ensuring high-temperature resistance, it also has good toughness and anti-aging ability, which can extend the service life under extreme conditions such as fire. At the same time, the wrapping ratio of the two can be flexibly adjusted according to different working conditions, making the product more adaptable.
[0048] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Those skilled in the art to which this invention pertains can make various modifications and refinements without departing from the spirit and scope of the present invention. Therefore, the scope of protection of this invention shall be determined by the claims.
Claims
1. A halogen-free, low smoke, low toxicity, flame-retardant, fire-resistant power cable, characterized in that, The application relates to a cable, which comprises the following parts: a plurality of wire cores (1) arranged in tangency; a flame-retardant filling structure (2) arranged between two adjacent wire cores (1); a composite wrapping structure (3) wrapped outside the wire cores (1) and the flame-retardant filling structure (2) and forming a cable core with a circular cross section; an inner sheath (4) extruded on the outer wall of the composite wrapping structure (3); an armour layer (5) wrapped outside the inner sheath (4); a flame-retardant layer (6) wrapped outside the armour layer (5); an outer sheath (7) extruded on the outer wall of the flame-retardant layer (6); wherein the composite wrapping structure (3) comprises a plurality of wrapping structure layers, at least a mica tape wrapping structure layer and a glass filament tape wrapping structure layer; the composite wrapping structure (3) comprises three wrapping structure layers, wherein the inner layer wrapping structure (31) comprises a mica tape wrapping structure layer, the middle layer wrapping structure (32) comprises a glass filament tape wrapping structure layer, and the outer layer wrapping structure (33) comprises a mica tape wrapping structure layer or a copper foil tape wrapping structure layer.
2. The halogen-free low smoke low toxicity flame-retardant fire resistant power cable according to claim 1, characterized in that, The copper foil tape wrapping structure layer comprises double-layer copper foil tape wrapping layers, the winding direction of the inner layer copper foil tape wrapping layer is the same as that of the middle layer wrapping structure (32), and the winding direction of the outer layer copper foil tape wrapping layer is opposite to that of the inner layer copper foil tape wrapping layer.
3. The halogen-free low smoke low toxicity flame-retardant fire resistant power cable according to claim 1, wherein, The wrapping overlap rate of the mica tape wrapping structure layer is 25-35%.
4. The halogen-free low smoke low toxicity flame-retardant fire resistant power cable according to claim 3, characterized in that, The wrapping overlap rate of the glass filament tape wrapping structure layer is 20-25%.
5. The halogen-free low smoke low toxicity flame and fire retardant electrical power cable of claim 1, wherein, The wrapping angles of the mica tape wrapping structure layer and the glass filament tape wrapping structure layer are 30-40 DEG, and the wrapping directions are the same.
6. The halogen-free low smoke low toxicity flame and fire retardant electrical power cable of claim 1, wherein, The wire core (1) comprises a twisted copper conductor (11), a mica tape wrapping layer (12) wrapped outside the twisted copper conductor (11), and a crosslinked polyethylene insulation layer (13) extruded outside the mica tape wrapping layer (12).
7. A halogen-free low smoke low toxicity, flame-retardant, fire-resistant power cable according to claim 6, characterized in that, The mica tape wrapping layer (12) comprises right-overlapping-wound mica tape, and the wrapping overlap rate is greater than or equal to 20%.
8. The halogen-free low smoke low toxicity flame and fire retardant electrical power cable of claim 1, wherein, The flame-retardant filling structure (2) comprises an alkali-free glass fiber filling rope.
9. The halogen-free low smoke low toxicity flame and fire retardant electrical power cable of claim 1, wherein, The armour layer (5) comprises double-layer galvanized steel tape wrapping layers, each layer of the galvanized steel tape is a gap wrapping structure, and the outer layer galvanized steel tape is overlapped outside the gap of the inner layer galvanized steel tape.
10. A halogen free, low smoke, low toxicity, flame retardant, fire resistant power cable as claimed in claim 1, wherein, The flame-retardant layer (6) comprises an alkali-free glass fiber tape wrapping layer, and the outer sheath (7) comprises a halogen-free low-smoke flame-retardant polyolefin sheath layer.