CN201174276Y - Environmentally friendly and safe fire-resistant power cables - Google Patents

Abstract

The utility model relates to an environment-friendly and safe fire-resistant power cable. It is characterized in that: the inner core of the cable is composed of a conductive wire core, a refractory layer, and an insulating layer. The refractory layer is wrapped around the conductive wire core, and the outer layer of the refractory layer is an insulating layer. Composed of water belt, inner lining layer, copper wire and copper belt combination shielding layer, semi-conductive resistance water buffer belt, aluminum foil, and intumescent halogen-free flame-retardant protective layer. There can be more than one cable inner core in the cable outer layer. There are three or four or five cable inner cores inside the cable outer layer. The utility model has the advantage of improving fire prevention and safety effects due to the adoption of the above structure. It will not spread, burn and produce harmful hydrogen halide gas, and also has a shielding system for short circuit protection, which meets the design requirements of green and environmentally friendly safety cables.

Description

Environmentally friendly and safe fire-resistant power cables

technical field

The utility model relates to a power cable used as electric energy transmission in automatic safety fire-fighting systems and emergency power supply systems of some high-rise buildings, petroleum, mines, metallurgy, ships, power stations, subways, tunnels, etc.

Background technique

At present, in domestic high-rise buildings, petroleum, mining, metallurgy, ships, power stations, subways, tunnels and other occasions with high fire safety conditions, the insulation layer and sheath layer of cables used are mostly made of halogen-containing insulating materials. Once the fire spreads, it will not only produce a large amount of dense smoke, but also produce highly corrosive hydrogen halide gas with "secondary disasters", endangering human life, endangering equipment and polluting the environment. With the rapid development of the world economy and the requirements of the world environmental organization for environmental protection, it is urgent to develop green and environmentally friendly safety cables to meet the needs of sustainable development of human beings. This is the development trend of all countries in the world and the common aspiration of people all over the world.

Contents of the invention

The purpose of this utility model is to provide a fireproof, waterproof, non-toxic, environmental protection, high safety, suitable for security, disaster relief power supply and emergency power supply for fire extinguishing, alarm, lighting, communication, etc. The low-smoke, halogen-free, non-toxic and pollution-free green safety cable used is an environmentally friendly and safe fire-resistant power cable. The utility model designs an environment-friendly and safe fire-resistant power cable, which includes a cable inner core and a cable outer layer. The outer layer of the refractory layer is an insulating layer, and the outer layer of the cable is composed of a semiconductive resistance hose, an inner lining layer, a combined shielding layer of copper wire and copper tape, a semiconductive resistance water buffer zone, aluminum foil, and an intumescent halogen-free flame retardant from the inside to the outside. composition of the protective layer. There can be more than one cable inner core in the cable outer layer. There are three or four or five cable inner cores inside the cable outer layer. The insulating layer is formed by three layers of co-extrusion, the inner layer is a semi-conductive conductor shielding layer, the outer layer is a semi-conductive insulating shielding layer, and the middle layer is a cross-linked polyethylene insulating layer. The three layers are extruded from special low-smoke and halogen-free insulating materials . The conductive wire core is made of several soft round copper wires with the same diameter in a regular, concentric manner, and successive layers are twisted in different directions. The refractory layer is made of high-quality mica tape. The combined shielding layer of copper wire and copper tape is composed of a layer of copper wire wrapped around a layer of copper tape. The utility model has the advantage of improving fire prevention and safety effects due to the adoption of the above structure. It will not spread, burn and produce harmful hydrogen halide gas, and also has a shielding system for short circuit protection, which meets the design requirements of green and environmentally friendly safety cables.

Description of drawings

Fig. 1 is a structural cross-sectional view of the utility model with three cable inner cores,

Fig. 2 is a structural cross-sectional view of the utility model with four cable inner cores,

Below in conjunction with accompanying drawing and example the utility model is described in detail.

Detailed ways

The figure includes a cable inner core 1 and a cable outer layer 2. It is characterized in that: the cable inner core 1 is composed of a conductive wire core 3, a refractory layer 4, and an insulating layer 5. The refractory layer 4 is wrapped around the conductive wire core 3. The outer layer of layer 4 is an insulating layer 5, and the outer layer of the cable 2 is composed of a semiconductive resistance water belt 6, an inner lining layer 7, a combined shielding layer of copper wire and copper tape 8, a semiconductive resistance water buffer belt 9, and an aluminum foil 10 from the inside to the outside. , Intumescent halogen-free flame-retardant protective layer 11. There can be more than one cable inner core 1 in the cable outer layer 2 . There are three or four or five cable inner cores 1 in the cable outer layer 2. The insulating layer 5 is formed by three-layer co-extrusion, the inner layer is a semi-conductive conductor shielding layer 12, the outer layer is a semi-conductive insulating shielding layer 14, the middle is a cross-linked polyethylene insulating layer 13, and the three layers are all insulated by low-smoke and halogen-free special Material extrusion. Conductive wire core 3 is regular by the same soft round copper wire of several diameters, presses concentric formula, and each successive level twists according to different directions and forms. The refractory layer 4 is made of high-quality mica tape. The combined shielding layer 8 of copper wire and copper tape is composed of a layer of copper wire wrapped around a layer of copper tape.

The technical scheme of the present utility model is accomplished like this, and the conductive wire core 3 of cable is by the stranded conductor that many soft garden copper single wires form by concentric layered twisting system. The refractory layer 4 is composed of high-quality refractory synthetic mica tape, which is wrapped on the conductive core 3. The insulating layer 5 is a semi-conductive conductor shielding layer 12 on the inner layer, and a semi-conducting insulating shielding layer 14 on the outer layer. The middle layer is cross-linked Polyethylene insulating layer 13, three layers are extruded by special low-smoke and halogen-free insulating materials, which are successively coated on the outside of refractory layer 4, and semi-conductive resistance hose 6 is overlapped and wrapped on the outside of insulating layer 5, low-smoke and non-halogen The inner lining layer 7 of halogen is extruded and wrapped outside. The combined shielding layer 8 of copper wire and copper tape is completed by winding a plurality of soft round copper wires loosely on the outside of the inner lining layer 7, and then wrapping a copper tape in reverse direction to tie it tightly. The semi-conductive buffer water blocking tape 9 is wrapped around the The outer side of the copper wire and copper tape combination shielding layer 8 plays a buffering and water-blocking effect. Then wrap aluminum foil 10 around or longitudinally on the outside of the semi-conductive buffer water-blocking belt 9, and extrude a layer of expandable halogen-free flame-retardant protective layer 11 made of expandable low-smoke, halogen-free, flame-retardant and refractory polyolefin on the outermost side. As a sheath, this is a new type of intumescent flame-retardant refractory sheath. It will expand rapidly in case of fire and has good heat insulation effect.

The cross-sectional area of the conductive wire core 3 of the present utility model is 4-500mm ² , the geometric shape is circular, and it is made of several soft round copper wires with the same diameter, which are regular and concentric, and each layer is successively arranged according to different direction twisted. The insulated wire core can be single-core, three-core, or four-core, with fixed geometric shape, high stability, and little influence on the bendability of the cable.

The refractory layer 4 of the utility model is made of high-quality mica tape specially used for fire-resistant safety cables, which has excellent fire-resistant and flame-retardant effects, and can still maintain good dielectric strength at the combustion temperature. The insulating layer 5 of the present invention is composed of three layers, which are formed by three-layer co-extrusion. The inner layer is a semi-conductive conductor shielding layer 12, the outer layer is a semi-conductive insulating shielding layer 14, and the middle layer is a cross-linked polyethylene insulating layer 13. The three layers are all extruded from special low-smoke and halogen-free insulating materials. Through special cross-linking treatment, the linear molecular structure of polyethylene is transformed into a three-dimensional network molecular structure, which greatly improves the electrical, physical and mechanical properties of the product. And other special properties, not only high temperature resistance but also has the characteristics of non-flammability and no generation of hydrogen halide gas. In this way, the cable can not release harmful gas and smog when burning, and will not cause "secondary disasters".

The combined shielding layer 8 of copper wire and copper tape of the utility model is composed of a layer of copper wire and a layer of copper tape wrapping. The cross section of the shielding layer and the cross section of the main wire core are configured according to a certain ratio, consisting of 16, 25, 35, 50.. .... Various specifications. The shielded cable of this structure can resist electromagnetic induction, poor grounding and power line conduction interference, reduce inductance, and prevent excessive induced electromotive force. The combined shielding layer 8 of copper wires and copper strips can not only suppress the emission of electromagnetic waves, but also serve as a channel for short-circuit current and protect the neutral wire core.

The semi-conductive resistance water belt 6 of the utility model has the dual functions of semi-conduction and water resistance, and is overlapped and wrapped outside the cable insulation shielding layer as a waterproof structure. The 0.5 mm thick water blocking tape is selected, and when it encounters water, it can quickly expand to a height of 12 mm, so as to achieve a good water blocking effect. The semi-conductive buffer water-blocking tape with triple functions of semi-conducting, buffering and water-blocking is overlapped and wrapped outside the combined shielding layer 8 of copper wire and copper tape. It has the same water-blocking principle and also has the function of buffering. After this band encounters water expansion, the water that can block up the copper wire copper tape combined shielding layer 8 is impenetrable. Effectively prevent the intrusion of moisture and moisture.

铝箔的结构，在高于1000℃的火焰温度条件下，经过20min后，内部的温度超过600℃，铝箔10开始熔融。The utility model adopts aluminum foil 10 for wrapping around or longitudinally. The light and heat reflectance of the aluminum foil 10 is greater than 90%, and cooperates with a new type of expansion-type flame-retardant and fire-resistant sheath to slow down heat conduction. At a flame temperature higher than 1000°C, after 90 minutes, the internal temperature does not exceed 450°C. Ordinary low-smoke halogen-free flame-retardant refractory sheath

According to the structure of the aluminum foil, under the flame temperature condition of higher than 1000° C., after 20 minutes, the internal temperature exceeds 600° C., and the aluminum foil 10 starts to melt.

The utility model uses the expansion-type halogen-free flame-retardant protective layer 11, adopts the expansion-type flame-retardant technology and uses nitrogen as the flame-retardant element. The sheath material composed of three parts (foaming agent) expands rapidly, forming a dense porous carbon foam layer on the surface, which is firmly attached to the cable, which plays a good role in heat insulation, oxygen insulation, smoke suppression, and can prevent produce the effect of dripping. The fire-resistant outer sheath has good flame-retardant, smoke-suppressing and self-extinguishing functions, is low-smoke, halogen-free, flame-retardant, has high elongation at break (>350%), and is easy to process. The flame-retardant and fire-resistant function of the expandable halogen-free flame-retardant protective layer 11 is mainly through the thermal insulation of the expanded carbon layer-the low heat conduction of the foam structure, the reflection of heat radiation, and the gas barrier effect, which limits the oxygen supply to the underlying polymer and inhibits The release of flammable degradation gases and the effective prevention of the melting and dripping behavior of polymer combustion can achieve the effect of flame retardancy and fire resistance.

Claims (7)

1, environmental protection and safety type fireproof power cable; comprise cable inner core, cable outer layer; it is characterized in that: the cable inner core is made up of conductor wire core, flame retardant coating, insulating barrier; flame retardant coating is wrapped on conductor wire core; be screen outside flame retardant coating, cable outer layer is made up of block water buffer strip, aluminium foil, halogen-free intumescent flame-retardant protective layer of semiconductive waterstop, inner covering, copper wire copper strips combination screen, semiconductive from inside to outside according to this.

2, by the described environmental protection and safety type fireproof power cable of claim 1, it is characterized in that: the cable inner core in the cable outer layer can have more than one.

3, by the described environmental protection and safety type fireproof power cable of claim 1, it is characterized in that: the cable inner core in the cable outer layer has three or four or five.

4, by the described environmental protection and safety type fireproof power cable of claim 1, it is characterized in that: insulating barrier is formed by three-layer co-extruded, internal layer is the semiconductive conductor shield, skin is the semiconductive insulation screen, the centre is crosslinked polyetylene insulated layer, and three layers by the extrusion modling of low smoke and zero halogen special insulation material.

5, by the described environmental protection and safety type fireproof power cable of claim 1, it is characterized in that: conductor wire core is well-regulated by the identical soft round copper wire of some diameters, press concentric type, and each level is made according to different direction strands and formed in succession.

6, by the described environmental protection and safety type fireproof power cable of claim 1, it is characterized in that: flame retardant coating constitutes for the high-quality mica tape.

7, by the described environmental protection and safety type fireproof power cable of claim 1, it is characterized in that: copper wire copper strips combination screen is formed by one deck copper strips is wrapped outside one deck copper wire.

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