CN215450977U

CN215450977U - Single-core waterproof flame-retardant fire-resistant cable for 35 kV-level rail transit

Info

Publication number: CN215450977U
Application number: CN202022853599.7U
Authority: CN
Inventors: 郭国庆; 王岩鹏; 陈善求; 阳文锋; 曾婉; 贾超民; 魏向南
Original assignee: Gold Cup Electric Hengyang Cable Co Ltd
Current assignee: Gold Cup Electric Hengyang Cable Co Ltd
Priority date: 2020-12-02
Filing date: 2020-12-02
Publication date: 2022-01-07
Anticipated expiration: 2030-12-02

Abstract

The utility model discloses a single-core waterproof flame-retardant fire-resistant cable for 35 kV-level rail transit, which comprises a conductor, an insulating co-extrusion layer and a metal shielding layer, wherein the insulating co-extrusion layer is coated outside the conductor, the metal shielding layer is coated outside the insulating co-extrusion layer, the metal shielding layer is further coated with a water-blocking layer, a composite flame-retardant fire-proof layer is coated outside the water-blocking layer, an armor layer is coated outside the composite flame-retardant fire-proof layer, and an outer protective layer is coated and compounded on the armor layer. The flame retardant property of the flame retardant cable meets the requirement of flame retardant B1 grade in GB31247-2014 Cable and optical cable combustion property grading standard, and the fire resistance meets the requirement of TICW 8-2012 insulating fire-resistant power cable with rated voltage of 6kV to 35kV extrusion coating, so that the product not only can minimize possible fire hazard, but also can ensure that the cable can normally run for long-time power supply when a fire occurs, and provides guarantee for fire rescue and power supply of special equipment.

Description

Single-core waterproof flame-retardant fire-resistant cable for 35 kV-level rail transit

Technical Field

The utility model relates to the technical field of cables, in particular to a single-core waterproof flame-retardant fire-resistant cable for 35kV rail transit.

Background

With the continuous acceleration of urbanization and the medium-and-long-term development and planning of railways in China, very high requirements on flame retardance and fire resistance of medium-voltage power cables are put forward in medium-voltage power distribution systems in engineering buildings and rail transit tunnels, and the flame-retardant fire-resistant medium-voltage power cables used in specific places have important significance on the fire safety of the engineering buildings and the rail transit.

For a long time, due to the lack of cable combustion performance grading standards, only low-smoke zero-halogen class A bundled combustion needs to be achieved before, the huge hazard of fire disasters in crowded public places is consistently recognized, and cables with higher combustion performance grades are needed, namely the necessity of meeting B1 grade flame-retardant cables in the standard GB31247-2014 is needed. The GB31247 standard quantifies the length of flame spread, heat release rate/total amount, smoke rate/total amount, and grading of combustion drops/particles, smoke toxicity, and corrosivity in cable combustion test, and ensures that the fire safety requirements of the cable are more scientific and reasonable.

In addition, in practical application of the existing track traffic cable, the existing track traffic cable can be partially and completely immersed in water, water molecules can permeate into the cable, so that the insulating electrical performance is reduced, even safety accidents occur, and the cable is required to have excellent waterproof performance; the conventional flame-retardant and fire-resistant power cable is mostly combined by mica tapes, flame-retardant materials and the like during design, the heat insulation performance and the fire blocking performance of plastics are not particularly good, the cable can not be supplied with power for a long time when a fire disaster occurs, and the cable is not beneficial to smooth escape of fire personnel.

SUMMERY OF THE UTILITY MODEL

The utility model aims to solve the technical problem of providing a single-core waterproof flame-retardant fire-resistant cable for 35 kV-level rail transit aiming at the defects of the existing rail transit cable.

The technical problem to be solved by the utility model can be realized by the following technical scheme:

35 waterproof fire-retardant fire resisting cable of single core for rail transit of kV level, including the conductor, the cladding is at the insulating co-extrusion layer outside the conductor, the cladding is at the metallic shield layer outside insulating co-extrusion layer, its characterized in that, it has the water blocking layer still to clad outside the metallic shield layer, at the compound fire-retardant layer that separates of cladding outside the water blocking layer, at the compound armor that separates the fire layer of cladding, at the armor cladding complex there is the outer jacket.

In a preferred embodiment of the utility model, the water-proof layer is in a wrapped two-layer water-proof tape structure form, or a longitudinal wrapping structure form of an aluminum-plastic composite tape, or a combination of the two.

In a preferred embodiment of the utility model, the composite flame-retardant fire-barrier layer is formed by compounding the flame-retardant layer and the fire-barrier layer from inside to outside.

In a preferred embodiment of the utility model, the flame-retardant layer is formed by compounding a high-flame-retardant glass cloth tape, an alkali-free glass fiber tape and an oxygen barrier.

In a preferred embodiment of the utility model, the fire barrier layer is formed by extrusion or wrapping with a ceramifiable refractory material.

Due to the adoption of the technical scheme, the water-blocking layer is additionally arranged on the outer surface of the metal shielding layer, and the water-blocking agent contained in the water-blocking tape can rapidly expand when meeting water to form a large-volume jelly, so that water vapor is prevented from further permeating. In addition, after the aluminum-plastic composite tape is longitudinally wrapped, a closed space can be formed for the insulating outer layer, water vapor is prevented from entering, and the waterproof performance requirement of the cable is met.

The high-flame-retardant glass cloth belt and the alkali-free glass fiber in the flame-retardant layer have high oxygen index, can absorb heat during combustion, prevent flame from penetrating and protect the internal product structure; the oxygen insulation material can absorb heat generated by thermal decomposition, and the overall temperature of the cable is reduced, so that the requirement on the flame retardant property of the cable is met;

the fire barrier layer can be made of ceramic materials, a compact shell is quickly formed in the combustion or high-temperature process, the heat insulation effect is very good after incrustation, meanwhile, the shell does not fall under the condition of flame combustion, flame is prevented from entering the inner layer of the cable, and the requirement on the fire resistance of the cable is met.

The flame retardant property of the flame retardant cable meets the requirement of flame retardant B1 grade in GB31247-2014 Cable and optical cable combustion property grading standard, and the fire resistance meets the requirement of TICW 8-2012 insulating fire-resistant power cable with rated voltage of 6kV to 35kV extrusion coating, so that the product not only can minimize possible fire hazard, but also can ensure that the cable can normally run for long-time power supply when a fire occurs, and provides guarantee for fire rescue and power supply of special equipment.

Drawings

FIG. 1 is a schematic cross-sectional view of a single-core waterproof flame-retardant fire-resistant cable for 35 kV-level rail transit according to the utility model.

Detailed Description

The utility model is further described below in conjunction with the appended drawings and detailed description.

Referring to fig. 1, the single-core waterproof flame-retardant fire-resistant cable for 35 kV-level rail transit shown in the figure comprises a conductor 01, an insulating co-extrusion layer 02 coated outside the conductor 01, a metal shielding layer 03 coated outside the insulating co-extrusion layer 02, a water-blocking layer 04 coated outside the metal shielding layer 03, a composite flame-retardant fire-proof layer 05 coated outside the water-blocking layer 04, an armor layer 06 coated outside the composite flame-retardant fire-proof layer 05, and an outer protective layer 07 coated on the armor layer 06.

The water-resistant layer 04 is one or a combination of two of a lapping two-layer water-resistant tape structure form and a longitudinal lapping aluminum-plastic composite tape structure form. The water-blocking agent contained in the water-blocking tape can be rapidly expanded when meeting water to form a large-volume jelly, so that water vapor is prevented from further permeating. In addition, after the aluminum-plastic composite tape is longitudinally wrapped, a closed space can be formed for the insulating outer layer, water vapor is prevented from entering, and the waterproof performance requirement of the cable is met

The composite flame-retardant fire-insulating layer 05 is formed by compounding a flame-retardant layer and a fire-insulating layer from inside to outside. The flame-retardant layer is formed by compounding a high-flame-retardant glass cloth belt, an alkali-free glass fiber belt and an oxygen barrier. The composite flame-retardant fire-insulating layer 05 is high in oxygen index of a medium-high flame-retardant glass cloth belt and an alkali-free glass fiber belt, can absorb heat during combustion, prevents flame from penetrating through and protects the structure of an internal product; the oxygen insulation material can absorb heat generated by thermal decomposition, and the overall temperature of the cable is reduced, so that the requirement on the flame retardant property of the cable is met.

The fire barrier layer is formed by extruding or wrapping ceramic refractory materials. It is at burning or high temperature in-process, forms fine and close casing fast, and the heat insulation effect is very good behind the crust, and the casing can not appear the low phenomenon under the condition of flame burning simultaneously, avoids flame to get into the cable inlayer, satisfies the fire resistance requirement of cable.

Take WDZAN-YJA6326/35kV 1 × 300 as an example:

the conductor 01 is made of copper. The insulating co-extrusion layer 02 is a three-layer co-extrusion layer which is composed of an inner shielding layer, an insulating layer and an outer shielding layer from inside to outside in sequence. The thickness of the inner shielding layer is 1.0mm, the material of the insulating layer is crosslinked polyethylene, the thickness is 10.5mm, and the thickness of the outer shielding layer is 1.0 mm.

The metal shielding layer 03 is formed by wrapping a 0.12mm copper strip;

the water-resistant layer 04 adopts one or a combination of two of a wrapped two-layer water-resistant tape structure form and a longitudinal wrapping structure form of an aluminum-plastic composite tape to form a closed space to prevent water vapor from entering;

the composite flame-retardant fire-insulating layer 05 is formed by compounding a flame-retardant layer and a fire-insulating layer from inside to outside. The flame-retardant layer is wrapped by 2-8mm of an oxygen isolation layer and 2-6 layers of glass fiber tapes or glass cloth tapes, the fire isolation layer is made of ceramic materials with the thickness of 2-8mm, a compact shell is formed during combustion, flame is prevented from entering, and the integral temperature of the cable is reduced, so that the flame-retardant and fire-resistant performance of the cable is met;

the armor layer 06 is formed by lapping a non-magnetic stainless steel belt/copper belt;

the outer protective layer 07 is formed by extruding low-smoke halogen-free flame-retardant sheath materials;

and performing a flame-retardant A-type bundled combustion test on the product, wherein the non-metal content of the sample is 7-9L/m, and the carbonization height above the bottom edge of the blowtorch is less than 1.5m after combustion.

And carrying out a fire resistance test on the product, wherein the fire is supplied by a double-blast burner in the test, the flame temperature is higher than 850 ℃, a test voltage of 26kV is applied between the conductor and the metal shield, the fire supply time is 90-120min, the insulation is not broken down in the fire supply process, after the fire supply is stopped, the test voltage of 91kV is applied to the product, the application time is 15-30min, and the insulation is not broken down.

And (3) performing a waterproof test on the product, soaking the product in water for 72-108 hours, removing the composite layer outside the insulation, and observing by naked eyes to obtain the dry and waterless trace on the insulation surface.

Claims

The single-core waterproof flame-retardant fire-resistant cable for 1.35 kV-level rail transit comprises a conductor, an insulating co-extrusion layer coated outside the conductor and a metal shielding layer coated outside the insulating co-extrusion layer, and is characterized in that a water-resistant layer is further coated outside the metal shielding layer, a composite flame-retardant fire-proof layer is coated outside the water-resistant layer, an armor layer is coated outside the composite flame-retardant fire-proof layer, and an outer protective layer is coated and compounded on the armor layer; the composite flame-retardant fire-insulating layer is formed by compounding a flame-retardant layer and a fire-insulating layer from inside to outside; the flame-retardant layer is formed by compounding a high-flame-retardant glass cloth belt, an alkali-free glass fiber belt and an oxygen barrier.
2. A single-core waterproof flame-retardant fire-resistant cable for 35 kV-level rail transit according to claim 1, wherein the waterproof layer is one or a combination of two of a wrapped two-layer waterproof tape structure form and a longitudinal wrapping structure form of an aluminum-plastic composite tape.
3. A single-core waterproof flame-retardant fire-resistant cable for 35 kV-class rail transit according to claim 1, wherein the fire barrier layer is formed by extrusion or wrapping by adopting a ceramifiable fire-resistant material.