CN211062505U

CN211062505U - Fireproof power cable

Info

Publication number: CN211062505U
Application number: CN201922147553.0U
Authority: CN
Inventors: 刘源; 王浩淼; 吴琼琼; 王成忠
Original assignee: Shanghai Ronda Cable Group Co ltd
Current assignee: Shanghai Ronda Cable Group Co ltd
Priority date: 2019-12-04
Filing date: 2019-12-04
Publication date: 2020-07-21
Anticipated expiration: 2029-12-04

Abstract

The utility model discloses a fireproof power cable, which comprises a core conductor and a protective layer, wherein the core conductor is arranged on the inner layer; the core conductor comprises at least two conductors with different diameters, the conductors with different diameters are sequentially arranged clockwise or anticlockwise, an oxygen-isolating filling layer is filled between the core conductor and the outer protective layer, and the protective layer sequentially comprises a heat-insulating layer, an oxygen-isolating inner protective layer, a steel strip armor layer, a fire-resistant flame-retardant layer and an outer protective layer from inside to outside. During the use, the utility model discloses a cable combustion performance reaches B1 level, and the additional hierarchical regulation requirement that accords with d0, t0, a1 for the cable is under rated operating voltage, and flame temperature is not less than 750 ℃, and the fuse is continuous in confession fiery time 90 min.

Description

Fireproof power cable

Technical Field

The utility model mainly relates to the technical field of cables, in particular to fire prevention power cable.

Background

At present, with the rapid development of socioeconomic performance in China, the requirements on industrial intelligence and automation are higher and higher, the requirements on flame retardance in the traditional control cable, GB/T9330-2008 or IEC60332-3 in the national standard GB/T9330-2008 are generally adopted, and domestic mainstream cable enterprises have already formed fixed process requirements and belong to mature products in terms of the flame retardance of the products. And for the standard GB 31247-2014 cable and optical cable combustion performance grading, the research is not deep, and many people consider that IEC60332-3 flame-retardant B-type or A-type bundled combustion tests are qualified, and B1 in GB 31247 also meets the requirements, and the difference is large.

GB 31247-2014 Standard "Classification of Cable and Cable Combustion Performance" classifies the flame spread, heat release and smoke generation characteristics of a cable under a fire condition, and additionally classifies the smoke generation toxicity, corrosivity and combustion droppings/particles of the cable under the fire condition according to the requirements of different use places and users.

Therefore, in view of the above situation, there is a strong need in the market to develop a flame retardant B1 grade fireproof control cable to meet the requirements of new standards.

Disclosure of Invention

The utility model provides a to above-mentioned problem, a fire prevention power cable is provided, through setting up the sinle silk conductor of different diameters to at the sinle silk conductor outward around the package inoxidizing coating, make the cable have good fire behavior, combustion behavior reaches B1 level.

The purpose of the utility model can be realized by the following technical scheme: a fireproof power cable is characterized by comprising a core conductor of an inner layer and a protective layer arranged on an outer layer; the core conductor comprises at least two conductors with different diameters, the conductors with different diameters are sequentially arranged clockwise or anticlockwise, an oxygen-isolating filling layer is filled between the core conductor and the outer protective layer, and the protective layer sequentially comprises a heat-insulating layer, an oxygen-isolating inner protective layer, a steel strip armor layer, a fire-resistant flame-retardant layer and an outer protective layer from inside to outside.

Preferably, the number of each conductor with different diameters is 2-5, and the exterior of each conductor is respectively wrapped with a fire resistant mica layer and an insulating layer. The diameters of two or more than two conductors are in an equal ratio series, and the adjacent ratio is 1: 2.

Further, the thickness of the heat insulation layer is 0.4-0.6mm, and the heat insulation layer is formed by winding an alkali-free glass fiber belt; the thickness of the oxygen-insulating inner protective layer is 1.5-1.7mm, and the oxygen-insulating inner protective layer is formed by wrapping low-smoke halogen-free oxygen-insulating materials.

Compared with the prior art, the technical scheme of the utility model except whole technical scheme's improvement, still include the improvement in the aspect of many details, particularly, have following beneficial effect:

1. according to the improved scheme of the utility model, the core conductor comprises at least two conductors with different diameters, the conductors with different diameters are sequentially arranged clockwise or anticlockwise, and the oxygen-isolating filling layer is filled between the core conductor and the outer protective layer, so that the conductor has excellent fireproof and fire-resistant characteristics, smoothness of electric power and communication under the condition of fire can be ensured, and valuable time is won for escape and fire rescue of personnel;

2. in the technical scheme of the utility model, the inoxidizing coating is insulating layer, separates oxygen inner sheath, steel band armor, fire-resistant fire-retardant layer and oversheath in proper order from inside to outside, makes the utility model discloses a cable burning performance reaches B1 level, and additional grading accords with d0, t0, the regulation requirement of a1, makes the cable under rated operating voltage, and flame temperature is not less than 750 ℃, and the fuse is incessant within 90min of supplying fire;

3. the cable of the utility model has good heat insulation performance, the heat conductivity coefficient is 0.09W/Mk, especially, the interior after ablation is even honeycomb-shaped, and the cable has better fire resistance and heat insulation performance;

4. the utility model discloses a cable adopts multilayer fire resistive construction, under 650 ℃ -3000 ℃ of flame, can sinter into hard pottery form crust rapidly, does not ftracture, does not melt, does not drip, and this crust can effectively keep apart the infringement of high temperature flame to circuit inside, guarantees the unblocked of circuit under the conflagration condition.

Drawings

Fig. 1 is a schematic structural diagram of the present invention.

The labels in the figure are as follows:

1 copper conductor, 2 insulating layers and 3 fire-resistant mica layers;

4 insulating layers, 5 oxygen-isolating inner protection layers, 6 steel belt armor layers, 7 fireproof flame-retardant layers, 8 outer sheaths and 9 oxygen-isolating filling layers.

Detailed Description

The following detailed description of the embodiments of the present invention will be given with reference to the accompanying drawings to make it clear to those skilled in the art how to practice the invention. While the invention has been described in connection with its preferred embodiments, these embodiments are intended to be illustrative, and not to limit the scope of the invention.

As shown in fig. 1, a fireproof power cable is different from the prior art in that the fireproof power cable comprises a core conductor of an inner layer and a protective layer arranged on an outer layer; the core conductor comprises at least two conductors 1 with different diameters, the conductors with different diameters are sequentially arranged clockwise or anticlockwise, an oxygen-isolating filling layer 9 is filled between the core conductor and the outer protective layer, and the protective layer comprises a heat-insulating layer 4, an oxygen-isolating inner protective layer 5, a steel-belt armor layer 6, a fire-resistant flame-retardant layer 7 and an outer protective layer 8 from inside to outside.

When the insulating fireproof mica plate is used, the number of each conductor with different diameters is 2-5, and the exterior of each conductor is respectively wrapped with a fireproof mica layer 3 and an insulating layer 2. Be provided with the supporting layer between fire resistant mica layer and insulating layer, the supporting layer is made by coarse sand grain, even coating is on fire resistant mica layer surface, because the insulating layer adopts novel fire prevention material pottery polyolefin insulation material, thickness is 1.7mm, pottery polyolefin fire prevention insulation material still has excellent fire prevention except having the characteristic of ordinary polyolefin insulation material, fire-resistant characteristic, it can form hard ceramic form crust under the ignition of flame, under the high temperature condition, because the supporting role of coarse sand grain, make and form a structure of separating the sky between ceramic form crust and the fire resistant mica layer, have very good thermal-insulated fire-proof effect, can guarantee unobstructed of electric power and communication under the conflagration condition, the valuable time of striving for personnel to flee for and fire rescue.

In one embodiment, the core conductor comprises two conductors with different diameters, the conductors with different diameters are arranged clockwise in sequence, wherein the conductors adopt round annealed soft copper conductors, and one conductor is 240mm²The conductor is made of 37 copper wires with monofilament diameter of 2.96mm, and the other is 120mm²The conductor is made of 19 copper wires with monofilament diameters of 2.88mm, a round pressing stranding mode is adopted, the outer diameter of the conductor is reduced by 10%, the structure is compact, and direct current resistance meets standard requirements. The number of the first conductors is 3, the number of the second conductors is 2, referring to fig. 1, the outer part of each conductor is respectively wrapped with a fire-resistant mica layer and an insulating layer, the conductors with each diameter form a core conductor group, and the two core conductors are combined into a cable. The extruded insulating layers are distinguished by colors and are 240mm²Selecting red, yellow and green with the thickness of 120mm²Blue and black are selected.

The cable core is arranged clockwise according to yellow, red, green and blue black, the twisting direction is right direction when the cable is formed, the oxygen isolation layer is filled in the cable core gap, the material adopts a mixture formed by mixing nano-scale active aluminum hydroxide hydrate (or magnesium hydroxide hydrate) and sodium silicate according to a certain proportion, and the mixture contains a large amount of aluminum hydroxide hydrate (or magnesium hydroxide hydrate), so that a large amount of water is decomposed at high temperature to form water mist, thereby the effects of cooling and fire prevention are achieved, a hard shell can be formed after the high temperature, and the cable core conductor is further protected.

Furthermore, an elastic component is filled between the insulating layer and the oxygen isolating layer of the wire core conductor, wherein the elastic component is a polyether polyurethane water-swelling elastomer which can rapidly swell when meeting water and gas, so that the contact between flame and the insulating layer is delayed, and the wire core conductor is further protected.

In another embodiment, there are two conductors of different diameters, with an equal ratio between the diameters of the conductors, with adjacent ratios of 1:2, for example, with three conductors, the ratio of the diameters of the three conductors is 1:2: 4. The number of each conductor with different diameters is 2-5, the exterior of each conductor is respectively wrapped with a fire-resistant mica layer and an insulating layer, and the conductors with different diameters are arranged at intervals, namely, the conductors with small diameters and the conductors with large diameters are arranged at intervals. If the conductors have more than two different diameters, the conductors are arranged from small to large according to the diameter of the conductors. The thickness of two kinds of different diameter conductors of this embodiment, the outside parcel fire resistant mica layer of conductor is 0.14mm, and the thickness of minor diameter conductor external insulation layer is 1.2mm, and the thickness of major diameter conductor external insulation layer is 1.7mm, forms a set of at a big little conductor simultaneously, is filling the insulating material of one deck pottery polyolefin fire prevention between the insulating layer of this a set of conductor for form the tower bridge structure between a big little two, further strengthen the support.

The oxygen-isolating filling layer is formed by mixing active aluminum hydroxide hydrate or magnesium hydroxide hydrate and sodium silicate, and ceramic fiber is added, wherein the ceramic fiber accounts for 30-60% by mass, the active aluminum hydroxide hydrate or magnesium hydroxide hydrate accounts for 5-25% by mass, and the sodium silicate accounts for 25-45% by mass. Because the mixture contains a large amount of aluminum hydroxide hydrate (or magnesium hydroxide hydrate), a large amount of water is decomposed at high temperature to form water mist, so that the effects of temperature reduction and fire prevention are achieved, a hard shell can be formed at high temperature, the heat insulation performance is good, the heat conductivity coefficient is 0.09W/Mk, particularly, the interior after ablation is uniform honeycomb-shaped, and the fire resistance and the heat insulation performance are better.

The thickness of the heat insulation layer is 0.4-0.6mm, the heat insulation layer is formed by wrapping an alkali-free glass fiber belt, and the glass fiber belt is environment-friendly and nontoxic, has high temperature resistance and fire resistance, and has excellent heat insulation performance. The thickness of the oxygen-insulating inner protective layer is 1.5-1.7mm, and the oxygen-insulating inner protective layer is formed by wrapping low-smoke halogen-free oxygen-insulating materials. The material is a low-smoke halogen-free oxygen-insulating material, the oxygen index of the material is not less than 45, a large amount of hydrated metal oxide is filled in the material, when the material is heated, water molecules are evaporated to absorb most of heat, the temperature of the cable can be reduced, the formed water molecules can dilute the concentration of oxygen around the cable, the burnt metal oxide product forms a hard shell and covers the cable core to prevent flame and heat from spreading to the inside of the cable, and meanwhile, the oxygen-insulating layer plays a role of an isolating sleeve.

In another embodiment, more than two conductors with different diameters form a core conductor, the small-diameter conductor forms a central circle, the large-diameter conductor surrounds the outside of the small-diameter conductor, the more important core conductor can be placed in the central circle during manufacturing, once a fire or other accidents happen, the conductor in the center can be guaranteed to run smoothly, and more precious time is strived for.

Further, the steel strip armor layer is made of double-layer galvanized steel strips, the width of each layer of galvanized steel strip is 25mm, the thickness of each layer of galvanized steel strip is 0.5mm, two layers of gaps are wrapped, and the gap is smaller than 22.5 mm. The steel tape armoring can improve the mechanical property of the cable and enhance the impact resistance; and secondly, the flame can be blocked, the internal structure of the cable is protected, and the flame is prevented from spreading inside the cable. The thickness of the fire-resistant flame-retardant layer is 2.5mm, and the fire-resistant flame-retardant layer is formed by mixing active aluminum hydroxide hydrate or magnesium hydroxide hydrate and sodium silicate. The high-temperature water mist is decomposed to generate a large amount of water to form water mist, so that the effects of cooling and fire prevention are achieved, a hard shell can be formed after the high temperature water mist is high, the high-temperature water mist has good heat insulation performance, the heat conductivity coefficient is 0.09W/Mk, particularly, the interior after ablation is uniform honeycomb-shaped, and the high-temperature water mist has better fire resistance and heat insulation performance. The outer sheath is extruded on the embossing armor layer in an extrusion mode, and the thickness of the outer sheath is 3.3 mm. The low-smoke halogen-free sheath material is selected, the oxygen index is greater than 36, and the outer sheath plays a role in protection.

It should be noted that many variations and modifications of the embodiments of the present invention are possible, which are fully described, and are not limited to the specific examples of the above embodiments. The above embodiments are merely illustrative of the present invention and are not intended to limit the present invention. In conclusion, the scope of the present invention shall include those changes or substitutions and modifications which are obvious to those of ordinary skill in the art, and shall be subject to the appended claims.

Claims

1. A fireproof power cable is characterized by comprising a core conductor of an inner layer and a protective layer arranged on an outer layer; the core conductor comprises at least two conductors with different diameters, the conductors with different diameters are sequentially arranged clockwise or anticlockwise, an oxygen-isolating filling layer is filled between the core conductor and the outer protective layer, and the protective layer sequentially comprises a heat-insulating layer, an oxygen-isolating inner protective layer, a steel strip armor layer, a fire-resistant flame-retardant layer and an outer protective layer from inside to outside.

2. A fire-resistant power cable as claimed in claim 1, wherein the number of each of the conductors having different diameters is 2 to 5, the exterior of each conductor is covered with a fire-resistant mica layer and an insulating layer, the conductors having each diameter form a core conductor group, and the two core conductor groups are combined into a cable.

3. A fire-resistant power cable according to claim 1, wherein the number of the conductors of each diameter is 2-5, the exterior of each conductor is covered with a fire-resistant mica layer and an insulating layer, and the conductors of different diameters are spaced apart from each other.

4. A fire resistant power cable as claimed in claim 2 or 3, wherein the diameters of two or more of the conductors are in an equal ratio array, the adjacent ratio being 1: 2.

5. A fire-resistant power cable according to claim 1, wherein the thickness of the thermal insulation layer is 0.4-0.6mm, and the thermal insulation layer is formed by wrapping an alkali-free glass fiber tape; the thickness of the oxygen-insulating inner protective layer is 1.5-1.7mm, and the oxygen-insulating inner protective layer is formed by wrapping low-smoke halogen-free oxygen-insulating materials.

6. A fire-resistant electrical power cable according to claim 1, wherein the steel tape armoring layer is made of two layers of galvanized steel tapes, each layer having a width of 25mm and a thickness of 0.5 mm; the thickness of the fire-resistant flame-retardant layer is 2.5 mm.