CN217134062U

CN217134062U - Fire-resistant electric wire

Info

Publication number: CN217134062U
Application number: CN202220537602.0U
Authority: CN
Inventors: 黄万里; 赵迪; 欧阳湘璋; 廖锦仁; 杨淞涵; 李楷纯; 杨洪文; 王洪道
Original assignee: Guangzhou Nanyang Cable Group Co ltd
Current assignee: Guangzhou Nanyang Cable Group Co ltd
Priority date: 2022-03-11
Filing date: 2022-03-11
Publication date: 2022-08-05
Anticipated expiration: 2032-03-11

Abstract

The utility model discloses a fire-resistant electric wire, which comprises a conductor; the fireproof layer comprises a synthetic mica tape and glass fiber mesh cloth, the synthetic mica tape lapping cover is wound on the conductor, and the lapping width of the synthetic mica tape lapping cover is 0.2-0.4 mm; the glass fiber mesh cloth lapping cover is wound on the synthetic mica tape, and the lapping width of the lapping cover is 0.1-0.2 mm; and the insulating layer wraps the outer side of the fire-resistant layer. The utility model discloses an adopt the fine net cloth of glass and the closely mode of wrapping up of synthetic mica tape to reduce the clearance in the flame retardant coating, the net of the fine net cloth of glass can carry out further cutting to the wind channel moreover, reduces the velocity of flow of air current in the clearance to heat release amount when reducing the burning. The utility model relates to the technical field of cables.

Description

Fire-resistant electric wire

Technical Field

The utility model relates to a fire-resistant electric wire among the cable technical field.

Background

With the trend of diversified functions, intensified structures and intensive personnel of modern buildings, the requirement on the fireproof performance of the buildings is higher and higher. The cable has higher requirements on the fireproof and fire-resistant performance of the cable in the building in places such as high-rise buildings, subway facilities and the like which are difficult to escape in time or places with dense personnel. Generally, cables installed in crowded places require a class B1 in combustion performance.

However, although many fire-resistant wires have material properties that meet the class B1 flammability rating, due to the structural issues of their fire-resistant layers, gaps tend to form between the layered structures at bends when the cable is bent. When the outer protective sleeve is burned through at high temperature, the gaps become fine air ducts. High temperature causes high-speed airflow in the air channels to generate combustion supporting effect, so that the heat release amount is too high during combustion, and the requirement is not met in comprehensive detection.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to solve one of the technical problem that exists among the prior art at least, provide a fire-resistant electric wire, can reduce the clearance in the flame retardant coating to the cable is difficult for forming the wind channel in combustion process.

According to the embodiment of the utility model provides a fire-resistant electric wire is provided, include:

a conductor;

the fireproof layer comprises a synthetic mica tape and glass fiber mesh cloth, the synthetic mica tape lapping cover is wound on the conductor, and the lapping width of the synthetic mica tape lapping cover is 0.2-0.4 mm; the glass fiber mesh cloth lapping cover is wound on the synthetic mica tape, and the lapping width of the glass fiber mesh cloth lapping cover is 0.1-0.2 mm;

and the insulating layer wraps the outer side of the refractory layer.

According to the utility model discloses the embodiment, furtherly, the conductor is the annealing copper conductor, the conductor adopts first type solid conductor structure or second type stranded conductor structure.

According to the embodiment of the utility model provides a, furtherly, the number of piles of synthetic mica tape is the three-layer, the three-layer synthetic mica tape is lapped the lid each other and is wrapped.

According to the embodiment of the utility model, further, the thickness of synthetic mica tape is 0.12 ~ 0.16 mm.

According to the embodiment of the utility model provides a, furtherly, the mesh diameter of glass fibre net cloth is 1 ~ 3 mm.

According to the utility model discloses, furtherly, the insulating layer includes low smoke and zero halogen ceramic polyolefin insulating layer, low smoke and zero halogen ceramic polyolefin insulating layer wrap up in the flame retardant coating outside.

According to the embodiment of the utility model, furtherly, low smoke and zero halogen ceramic polyolefin insulating layer's thickness is 0.4 ~ 1.0 mm.

According to the embodiment of the utility model provides a, furtherly, the insulating layer still includes the fire-retardant B1 level irradiation crosslinked polyolefin insulating layer of low smoke and zero halogen, the fire-retardant B1 level irradiation crosslinked polyolefin insulating layer of low smoke and zero halogen wrap up in the ceramic polyolefin insulating layer outside of low smoke and zero halogen.

According to the embodiment of the utility model, furtherly, the thickness of low smoke and zero halogen fire-retardant B1 level irradiation crosslinked polyolefin insulating layer is 0.4 ~ 1.2 mm.

According to the embodiment of the utility model provides a, furtherly, fire-retardant B1 level irradiation crosslinked polyolefin insulating layer of low smoke and zero halogen with low smoke and zero halogen ceramic polyolefin insulating layer adopts double-deck crowded processing mode zonulae occludens altogether.

The utility model discloses beneficial effect includes at least: the utility model discloses an adopt the fine net cloth of glass and the closely mode of wrapping up of synthetic mica tape to reduce the clearance in the flame retardant coating, the net of the fine net cloth of glass can carry out further cutting to the wind channel moreover, reduces the velocity of flow of air current in the clearance to heat release amount when reducing the burning.

Drawings

In order to more clearly illustrate the technical solution in the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly described below. It is clear that the described figures represent only some embodiments of the invention, not all embodiments, and that a person skilled in the art can also derive other designs and figures from these figures without inventive effort.

FIG. 1 is a cross-sectional view of an embodiment of the present invention;

fig. 2 is a cross-sectional view of a refractory layer in an embodiment of the invention.

Detailed Description

This section will describe in detail the embodiments of the present invention, preferred embodiments of the present invention are shown in the attached drawings, which are used to supplement the description of the text part of the specification with figures, so that one can intuitively and vividly understand each technical feature and the whole technical solution of the present invention, but they cannot be understood as the limitation of the protection scope of the present invention.

In the description of the present invention, it should be understood that the orientation or positional relationship indicated with respect to the orientation description, such as up, down, front, rear, left, right, etc., is based on the orientation or positional relationship shown in the drawings, and is only for convenience of description and simplification of description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.

In the description of the present invention, a plurality of meanings are one or more, a plurality of meanings are two or more, and the terms greater than, smaller than, exceeding, etc. are understood as excluding the number, and the terms greater than, lower than, within, etc. are understood as including the number. If the first and second are described for the purpose of distinguishing technical features, they are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated or implicitly indicating the precedence of the technical features indicated.

In the description of the present invention, unless there is an explicit limitation, the terms such as setting, installing, connecting, etc. should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meaning of the terms in the present invention by combining the specific contents of the technical solution.

The embodiment of the utility model provides a fire-resistant electric wire can reduce the production in the wind channel in the fire-resistant layer when burning to heat release amount when reducing the burning. In a traditional fire-resistant electric wire, although fire-resistant layers are made of fire-resistant materials, specific layers of the fire-resistant electric wire are all designed by simple wrapping, and when a cable is bent, gaps are easy to appear between the layers of the bent part of the cable. In the combustion process, these gaps can act as the wind channel, and high temperature environment makes the air current pass through fast in the gap to drive flame and remove, increase the area of catching fire, improved the heat release volume, be difficult to pass in the combustion performance grade is appraised. Aiming at the problem, the fire-resistant layer in the fire-resistant wire is continuously covered and wrapped by a plurality of layers of synthetic mica layers, and gaps among the layers are cut; and the cover is lapped on the synthetic mica layer and is wrapped by the glass fiber gridding cloth, so that the synthetic mica layer is tightly attached, and meanwhile, the gridding on the glass fiber gridding cloth can block an air channel formed by a gap of the cover, the air velocity in the air channel is further reduced, and the heat release amount during combustion is reduced.

The combustion performance refers to the physical and chemical changes of the material when burning or meeting fire, and the performance is measured by the characteristics of the ignition performance and flame propagation performance of the surface of the material, heat generation, fuming, carbonization, weight loss, generation of toxic products and the like. The specific grading index is described in GB 31247-2014 "grading of cable and optical cable combustion performance".

Description figure 1 shows a cross-sectional structure of the present fire resistant electric wire. The conductor 1 in the fire-resistant wire is used as a conductor and is made of an annealed copper material, and the structure of the fire-resistant wire can be a solid structure or formed by stranding a plurality of wires. The outer side of the conductor 1 is wrapped by a fire-resistant layer 2 which is made of a fire-resistant material and can prevent flame from firing the conductor 1 inside. The outer side of the fire-resistant layer is continuously wrapped with an insulating layer 3 which is used for insulation on one hand and prevents the electrified conductor 1 from causing damage to the human body; on the other hand, the flame retardant layer can also be used. The insulating layer 3 is divided into two layers, the inner layer is a low-smoke halogen-free ceramic polyolefin insulating layer 31 which can be formed into a hard ceramic shell in the combustion process, and the shell can effectively isolate air from entering the inside of the cable and avoid the combustion of the inside due to high temperature; the outer fire-retardant B1 level irradiation crosslinked polyolefin insulating layer 32 that is low smoke and zero halogen, it has higher fire behavior, it can be strong to have the crust ability under the high temperature, the output is low characteristics, can form complete casing when the conflagration and adhere to on the cable, can prevent stretching of intensity of a fire, effectively reduce the impact of the flame that the cable inside received, the output is low when burning simultaneously, the heat release volume is little, nontoxic gas is released and is had good environmental protection performance, make things convenient for personnel to flee. And the low-smoke halogen-free ceramic polyolefin insulation layer 31 and the low-smoke halogen-free flame-retardant B1-grade irradiation crosslinking polyolefin insulation layer 32 are tightly connected in a double-layer co-extrusion processing mode.

Description figure 2 shows the cross-sectional structure of the flame-retardant coating 2 in the present flame-retardant wire. The flame retardant coating 2 is including synthesizing mica tape 21 and glass fiber net check cloth 22, and wherein the quantity of synthesizing mica tape 21 is the three-layer, and the synthetic mica tape 21 of three-layer is pasted each other and is connect fixedly around the mode of package through overlapping each other, overlaps the gap of covering around the package in-process reservation at the overlap of taking to make things convenient for the cable bending, promote the crooked flexibility ratio of cable. Continue to overlap on synthetic mica tape 21 and wrap glass fiber net check cloth 22, promote synthetic mica tape 21's wrap-around firmness on the one hand, on the other hand fills the gap between flame retardant coating 2 and insulating layer 3, and wherein net can cut this gap and divide to reduce air current through speed in the gap.

Referring to fig. 1, a fire-resistant electric wire according to an embodiment of the present invention includes a conductor 1, a fire-resistant layer 2, and an insulating layer 3. The conductor 1 is a main electric conductor for transmitting electric power. In particular, it is made using an annealed copper conductor. Copper is commonly used for cables and electrical and electronic components as a metal material having good ductility, thermal conductivity and electrical conductivity. Because its texture is softer, also make things convenient for the cable to buckle, prevent to cause conductor internal fracture or even break because of crooked cable. Annealing refers to slowly heating the metal to a temperature, holding for a sufficient time, and then cooling at a suitable rate. The purpose is to reduce hardness and improve machinability; the residual stress is reduced, the size is stabilized, and the deformation and crack tendency is reduced; refining grains, adjusting the structure and eliminating the structure defects. The annealing process is adopted for processing the copper conductor, so that the hardness of the metal copper can be further reduced, the interior of the conductor 1 is more compact, and the conductivity is improved. As for the specific structure of the conductor 1, a first-type solid conductor structure or a second-type stranded conductor structure may be employed. The first solid conductor structure refers to a single-core solid conductor with 99% of copper content, is hard and is generally used for large-power transmission; the second type of stranded conductor structure is formed by twisting a plurality of wires and then encapsulating the wires into a whole, and is more resistant to bending than a solid conductor.

The flame retardant coating 2 wraps the outer side of the conductor 1 and is used for retarding flame of the conductor 1. Referring to fig. 2, the refractory layer 2 includes a synthetic mica tape 21 and a glass fiber mesh 22. Mica is a rock-making mineral, is aluminosilicate of metals such as potassium, aluminum, magnesium, iron, lithium and the like, and is an important raw material for manufacturing electrical equipment due to very high insulating and heat-insulating properties, good chemical stability, strong acid resistance, strong alkali resistance and pressure resistance. The synthetic mica tape 21 lap cover is wrapped on the conductor 1, so that the insulation, flame retardation and protection effects on the conductor 1 can be achieved; also at high temperatures, mica releases water of crystallization to lower the ambient temperature. The lap cover is wrapped, namely, the strip-shaped structure is obliquely and spirally wound on the columnar structure, a gap is reserved between adjacent ring layers of the strip-shaped structure, the gap is called a lap cover gap, and the strip-shaped structure is saved while the columnar structure is convenient to bend. Specifically, the thickness of the synthetic mica tape 21 is 0.12-0.16 mm, the number of layers of the synthetic mica tape 21 is at least two, preferably three, layers, so that the flame-retardant protection of the conductor 1 can be well achieved, and the influence of excessive number of layers on the bending freedom degree of the cable can be reduced. The lapping width of the synthetic mica tapes 21 is 0.2-0.4 mm, the lapping width refers to the lapping overlapping width of the upper and lower layers of synthetic mica tapes 21, the lapping width is too small to cause loose structure, and the lapping width is too large to cause difficult bending of the cable.

The fiberglass gridding cloth 22 is wrapped on the synthetic mica tape 21 in a lap joint mode and serves as a transition layer of the synthetic mica tape 21 and the insulating layer 3. The glass fiber mesh fabric 22 is prepared by taking a glass fiber woven fabric as a base material and soaking a coating layer by using a high-molecular anti-emulsion, so that the glass fiber mesh fabric has good alkali resistance, flexibility and warp-weft tensile resistance, and has the functions of fire prevention and crack resistance. The glass fiber mesh fabric 22 can further fix the synthetic mica tape 21; and the glass fiber gridding cloth 22 is not easy to deform under the condition of combustion or high temperature, can continuously support the synthetic mica tape 21, and avoids the phenomenon that the synthetic mica tape 21 is embrittled and falls off. Meanwhile, in the production process, the insulating layer 3 enters the meshes after being extruded to form tight combination, so that the whole gap is reduced, and the dropping matters formed after the insulating material is carbonized during combustion can also be reduced. The cover lapping width of the glass fiber mesh cloth 22 is 0.1-0.2 mm, and the mesh diameter of the glass fiber mesh cloth 22 is 1-3 mm.

The insulating layer 3 wraps the outer side of the fire-resistant layer 2 and mainly plays a role in insulation and protection. The insulating layer 3 comprises a low-smoke halogen-free ceramic polyolefin insulating layer 31 and a low-smoke halogen-free flame-retardant B1-grade irradiation crosslinking polyolefin insulating layer 32. Wherein, the low-smoke halogen-free ceramic polyolefin insulating layer 31 is of an inner layer structure, the thickness is 0.4-1.0 mm, and the oxygen index is not lower than 43%. The low-smoke zero-halogen ceramic polyolefin insulating layer 31 is directly contacted with the glass fiber mesh 22 in the fire-resistant layer 2. Low smoke and halogen free is a material classification of wire sheaths in the wire and cable industry, which consists of thermoplastic or thermosetting materials that emit low smoke when heated and are themselves free of halogens. Under the combustion environment of 105 ℃, the smoke density generated by the low-smoke halogen-free sheath is lower, so that the visibility of a fire scene is improved, and favorable visual conditions are provided for people to escape from the fire scene; but also can avoid suffocation caused by too much smoke inhaled by people. The ceramic processing mode that adopts the vulcanization makes the rubber sheath possess similar ceramic physical characteristic, and during high temperature or burning, the pottery porcelain rubber sheath can become hard ceramic shell in the short time, and inside this casing can effectively isolated air entering cable, avoided inside to take place the burning because of high temperature.

The low-smoke halogen-free flame-retardant B1-grade irradiation crosslinked polyolefin insulating layer 32 is of an outer-layer structure, wraps the outer side of the low-smoke halogen-free ceramic polyolefin insulating layer 31, and is 0.4-1.2 mm in thickness and not lower than 45% in oxygen index. The low-smoke halogen-free flame-retardant B1-grade irradiation crosslinking polyolefin insulation layer 32 is a hierarchical structure of the fire-resistant wire which is directly contacted with the outside. The irradiation crosslinking technology is a technology for realizing macromolecular crosslinking reaction by adding chemical methods such as a crosslinking agent and the like or physical methods such as irradiation and the like so that a linear polymer is changed into a polymer with a three-dimensional space network structure. By combining the irradiation crosslinking technology and the flame retardant technology, the prepared cable material has excellent flame retardancy, high heat resistance and excellent physical and mechanical properties. The charring property of the polymer can be improved through irradiation crosslinking reaction, and the flame retardance of the polymer can be further improved. Therefore, the outermost low-smoke halogen-free flame-retardant B1-grade irradiation crosslinking polyolefin insulation layer 32 is made by adopting an irradiation crosslinking technology, so that the flame retardance of the fire-resistant wire can be effectively improved, and the internal structure is protected.

Further, the low-smoke halogen-free ceramic polyolefin insulation layer 31 and the low-smoke halogen-free flame-retardant B1-grade irradiation crosslinking polyolefin insulation layer 32 are tightly connected in a double-layer co-extrusion processing mode. The double-layer co-extrusion process refers to a process for feeding materials through two feeding holes and realizing simultaneous extrusion processing through an extruder. Because the raw material particles are tightly extruded under high pressure, the two hierarchical structures have high-strength connecting structures, the condition of staggered layers or falling off is reduced, and the generation of gaps is also reduced.

While the preferred embodiments of the present invention have been described in detail, it will be understood by those skilled in the art that the invention is not limited to the details of the embodiments shown, but is capable of various modifications and substitutions without departing from the spirit of the invention.

Claims

1. A fire resistant electrical wire, comprising:

a conductor (1);

the fireproof layer (2) comprises a synthetic mica tape (21) and glass fiber mesh cloth (22), the synthetic mica tape (21) covers the conductor (1), and the width of the cover is 0.2-0.4 mm; the lapping cover of the glass fiber mesh cloth (22) is wound on the synthetic mica tape (21), and the lapping width of the lapping cover is 0.1-0.2 mm;

and the insulating layer (3) is wrapped on the outer side of the refractory layer (2).

2. The fire resistant electrical wire of claim 1, wherein: the conductor (1) is an annealed copper conductor, and the conductor (1) adopts a first-type solid conductor structure or a second-type stranded conductor structure.

3. The fire resistant electrical wire of claim 1, wherein: the number of layers of the synthetic mica tapes (21) is three, and the three layers of synthetic mica tapes (21) are lapped and lapped in a covering mode.

4. The fire resistant electrical wire of claim 1, wherein: the thickness of the synthetic mica tape (21) is 0.12-0.16 mm.

5. The fire resistant electrical wire of claim 1, wherein: the diameter of the meshes of the glass fiber mesh cloth (22) is 1-3 mm.

6. The fire resistant electrical wire of claim 1, wherein: insulating layer (3) are including low smoke and zero halogen ceramic polyolefin insulating layer (31), low smoke and zero halogen ceramic polyolefin insulating layer (31) wrap up in flame retardant coating (2) the outside.

7. The fire resistant electrical wire of claim 6, wherein: the thickness of the low-smoke halogen-free ceramic polyolefin insulating layer (31) is 0.4-1.0 mm.

8. The fire resistant electrical wire of claim 6, wherein: insulating layer (3) still include fire-retardant B1 level irradiation crosslinked polyolefin insulating layer of Low Smoke and Zero Halogen (LSZH) 32 level irradiation crosslinked polyolefin insulating layer (32) parcel in LSZH (LSZH) 1 level irradiation crosslinked polyolefin insulating layer (31) outside.

9. The fire resistant electrical wire of claim 8, wherein: the thickness of the low-smoke halogen-free flame-retardant B1-grade irradiation crosslinking polyolefin insulating layer (32) is 0.4-1.2 mm.

10. The fire resistant electrical wire of claim 8, wherein: the low-smoke halogen-free flame-retardant B1-grade irradiation crosslinked polyolefin insulating layer (32) and the low-smoke halogen-free ceramic polyolefin insulating layer (31) are tightly connected in a double-layer co-extrusion processing mode.