Novel anti-dripping environment-friendly cable

Abstract

The utility model provides a novel anti-dripping environment-friendly cable, which comprises a plurality of wire cores and a cabling wrapping layer tightly wrapping the plurality of wire cores together, and is characterized in that each wire core comprises a conductor, a fire-resistant layer wrapping the outer side of the conductor and an insulating layer wrapping the outer side of the fire-resistant layer in an extruding manner; the insulating layer comprises an inner insulating layer and an outer insulating layer which are co-extruded, the inner insulating layer is a polypropylene insulating layer, the outer insulating layer is a polyolefin insulating layer, a shielding layer is arranged on the outer side of the cabling wrapping layer, an oxygen barrier layer is extruded on the outer side of the shielding layer, an armor layer is arranged on the outer side of the oxygen barrier layer, and a sheath layer is arranged on the outer side of the armor layer. The outer side of the armor layer is extruded with an outer protective layer, the cabling wrapping layer is a ceramic flame-retardant belt, particularly a ceramic halogen-free low-smoke high-flame-retardant belt, and the cable effectively avoids the insulation dripping phenomenon during B1-level combustion.

Description

Technical Field

[0001] The utility model relates to the technical field of anti-drip cables, in particular to a novel anti-drip environmentally friendly cable. Background Art

[0002] Under high temperature or flame conditions, the shell of ordinary cables is prone to cracking, melting, and producing burning drops or burning particles, and the flame retardant effect is not good. During the use of cables, they will be affected by various surrounding media. The pH of the soil, the surrounding humidity, the heat and other environments will greatly affect the service life of the cables. Long-term soil acid-base corrosion will not only cause damage to the power supply system, but also cause leakage short circuits, thereby causing fires and major accidents. At present, most B1-level cable insulation uses silane cross-linked polyethylene insulation. Referring to the Chinese patent authorization number "CN213339817U", a high-insulation cable using silane cross-linked polyethylene insulation material includes an outer heat-conducting layer, a flame-retardant layer, a shielding layer, an insulating layer, an inner heat-conducting layer, a cable core and a plurality of support skeletons. The plurality of support skeletons are fixed inside the shielding layer along the axial direction of the shielding layer, the flame-retardant layer is fixed outside the shielding layer, the outer heat-conducting layer is fixed outside the flame-retardant layer, the insulating layer is arranged between the support rods of each two support skeletons, the inner heat-conducting layer is fixed inside the insulating layer, and the cable core is fixed inside the inner heat-conducting layer. The high-insulation cable adopts silane cross-linked polyethylene insulation material, and adopts an inner heat-conducting layer and an outer heat-conducting layer. Although the heat dissipation of the cable can be greatly improved, the cross-linked polyethylene material melts when exposed to high temperature, and paraffin-like oil will drip when burning. The B1-level multi-core insulated control cable or low-voltage power cable using this insulation material will often experience insulation dripping during the B1-level combustion test and cannot reach the d0 level. Utility Model Content

[0003] The utility model solves the problem of insulation dripping that often occurs during the B1 level combustion test in the prior art, and proposes a new type of anti-drip environmentally friendly cable, which effectively avoids the insulation dripping phenomenon during the B1 level combustion.

[0004] In order to achieve the above objectives, the following technical solutions are proposed:

[0005] A novel anti-drip environmentally friendly cable comprises a plurality of cores and a cable wrapping layer which tightly wraps the plurality of cores together, the core comprising a conductor and a fire-resistant layer wrapped around the outside of the conductor and an insulating layer extruded around the outside of the fire-resistant layer, the insulating layer comprising a double-layer co-extruded inner insulating layer and an outer insulating layer, the inner insulating layer being a polypropylene insulating layer, the outer insulating layer being a polyolefin insulating layer, a shielding layer being arranged on the outside of the cable wrapping layer, an oxygen-insulating layer being extruded around the outside of the shielding layer, an armor layer being arranged on the outside of the oxygen-insulating layer, an outer sheath being extruded around the outside of the armor layer, and the cable wrapping layer being a ceramic flame-retardant tape, specifically a ceramic halogen-free, low-smoke, high flame-retardant tape.

[0006] The inner insulating layer of the utility model adopts polypropylene insulation material, which has the advantages of wear resistance, bending deformation resistance, chemical corrosion resistance, heat resistance, excellent insulation performance and strong plasticity. The outer insulating layer adopts thermoplastic halogen-free low-smoke flame-retardant polyolefin insulation material, which has good flame retardant performance and will not produce toxic gases such as halogen gas. The cable wrapping layer adopts ceramic halogen-free low-smoke high flame retardant tape, which is tightly tied into the cable core, and crusts when exposed to fire, with good oxygen insulation and heat insulation effects, and can effectively isolate the high-temperature flame from invading the inside of the line. The raw material of polypropylene is propylene, which is obtained by polymerization to obtain synthetic resin. It is a crystalline polymer, referred to as PP. It has the appearance of a white waxy substance, which is light and transparent. Polypropylene itself is non-toxic, odorless, low in density, and has better strength, rigidity, hardness and heat resistance than low-pressure polyethylene. It can be used at about 100°C. It has the advantages of chemical corrosion resistance, heat resistance, excellent insulation performance and strong plasticity.

[0007] Preferably, the conductor is an oxygen-free copper wire core with a copper content of 99.95%, and the refractory layer is two layers of overlapping and wrapped calcined mica tapes.

[0008] The conductor of the utility model adopts an oxygen-free copper wire core with a copper content of 99.95%, has a low resistivity, and the structure of the conductor meets the requirements of the first-class solid conductor, the second-class stranded conductor or the fifth-class soft conductor in the GB / 3956 standard. The fire-resistant layer adopts two layers of 0.14mm calcined mica tapes with overlapping wrapping, and the wrapping coverage rate is 25%-30%. As the innermost protective layer, it prevents the flame from burning and causing the wire core to short-circuit or break, which can effectively protect the line and provide more protection for escape or rescue.

[0009] Preferably, the thickness of the inner insulating layer accounts for 30% of the total thickness of the insulating layer, and the thickness of the outer insulating layer accounts for 70% of the total thickness of the insulating layer. The total insulation thickness should comply with the requirements of GB / T 9330 standard.

[0010] Preferably, the shielding layer is woven from oxygen-free copper wires or is formed by overlapping and wrapping a single layer of red copper tape.

[0011] The shielding layer of the utility model adopts oxygen-free copper wire or copper tape. When copper wire braiding shielding is adopted, the braiding density is ≥80%, and the braiding single wire diameter requirement meets the requirements of GB / T 9330 standard. When copper tape shielding is adopted, the copper tape thickness is 0.1mm, the single layer is overlapped and wrapped, and the overlap rate is 15%-20%. The shielding layer has excellent electromagnetic shielding performance, prevents electromagnetic interference from itself and the outside world, and ensures the normal operation of the signal line.

[0012] Preferably, the oxygen barrier layer is a ceramic polyolefin oxygen barrier layer.

[0013] The oxygen barrier layer of the utility model adopts ceramic halogen-free low-smoke polyolefin oxygen barrier material, and the average thickness of the extruded package is controlled at 1.3mm-1.5mm. Under high-temperature flame conditions, the oxygen barrier layer crusts and does not drip, forming a dense protective layer, which has the effect of oxygen isolation and heat insulation, and can effectively isolate the high-temperature flame from invading the inside of the cable.

[0014] Preferably, the armor layer is two hot-dip galvanized steel strips which are overlapped and wrapped around the outer side of the oxygen-isolating layer, and the gap ratio of the steel strips is 40%-50%.

[0015] The armor layer of the utility model adopts hot-dip galvanized double steel belt armor. The steel belt is required to comply with the GB / T 9330 standard requirements and is used to enhance the tensile strength and compressive strength and protect the internal wire core from damage. Compared with the electro-galvanized steel belt, it has stronger anti-corrosion ability.

[0016] Preferably, the outer protective layer is a polyolefin sheath.

[0017] The polyolefin sheath of the utility model adopts B1-level halogen-free, low-smoke, highly flame-retardant polyolefin sheath material, and the extrusion thickness meets the requirements of GB / T 9330. When burning, no halogen acid gas is released, the smoke emission is extremely low, and the crusting performance is excellent, no dripping, protecting the internal wire core structure, non-toxic and environmentally friendly.

[0018] The beneficial effects of the utility model are as follows: the inner and outer insulation and the outer insulation layer are extruded at one time by double-layer co-extrusion, without stratification, the two layers of insulation cannot be peeled off, the inner insulation layer material has high insulation resistance, good heat resistance and excellent electrical insulation performance; the cable wrapping layer and the oxygen isolation layer are both made of ceramic materials, which form a crust when exposed to fire, play an oxygen isolation and heat insulation effect, and can effectively isolate the high-temperature flame from the damage to the inside of the cable. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a structural cross-sectional view of this embodiment;

[0020] Among them: 1. Conductor; 2. Fire-resistant layer; 3. Inner insulation layer; 4. Outer insulation layer; 5. Cabling sheath; 6. Shielding layer; 7. Oxygen barrier layer; 8. Armor layer; 9. Outer sheath. DETAILED DESCRIPTION

[0021] Example:

[0022] This embodiment proposes a new type of anti-drip environmentally friendly cable, referring to Figure 1 , including 3 cores and a cable wrapping layer 5 that wraps the 3 cores tightly together, the core includes a conductor 1 and a fire-resistant layer 2 wrapped around the outside of the conductor 1 and an insulating layer extruded around the outside of the fire-resistant layer 2, the insulating layer includes a double-layer co-extruded inner insulating layer 3 and an outer insulating layer 4, the inner insulating layer 3 is a polypropylene insulating layer, the outer insulating layer 4 is a polyolefin insulating layer, a shielding layer 6 is arranged on the outside of the cable wrapping layer 5, an oxygen-insulating layer 7 is extruded around the outside of the shielding layer 6, an armor layer 8 is arranged on the outside of the oxygen-insulating layer 7, an outer sheath 9 is extruded around the outer side of the armor layer 8, and the cable wrapping layer 5 is a ceramic flame-retardant tape, specifically a ceramic halogen-free low-smoke high flame-retardant tape. The conductor 1 is an oxygen-free copper core with a copper content of 99.95%, and the fire-resistant layer 2 is two layers of calcined mica tapes that are wrapped in an overlapping manner. The thickness of the inner insulating layer 3 accounts for 30% of the total thickness of the insulating layer, and the thickness of the outer insulating layer 4 accounts for 70% of the total thickness of the insulating layer. The total insulation thickness shall comply with the requirements of GB / T 9330. The shielding layer 6 is woven from oxygen-free copper wire or wrapped with a single layer of overlapping copper tape. The oxygen-isolating layer 7 is a ceramic polyolefin oxygen-isolating layer. The armor layer 8 is two hot-dip galvanized steel tapes wrapped with overlapping gaps on the outside of the oxygen-isolating layer 7, and the gap rate of the steel tapes is 40%-50%. The outer sheath 9 is a polyolefin sheath.

[0023] The inner insulating layer 3 of the utility model adopts polypropylene insulation material, which has the advantages of wear resistance, bending deformation resistance, chemical corrosion resistance, heat resistance, excellent insulation performance and strong plasticity. The outer insulating layer 4 adopts thermoplastic halogen-free low-smoke flame-retardant polyolefin insulation material, which has good flame retardant performance and will not produce toxic gases such as halogen gas. The cable wrapping layer 5 adopts ceramic halogen-free low-smoke high flame retardant tape, which is tightly tied into the cable core, and crusts when encountering fire, and has good oxygen insulation and heat insulation effects, and can effectively isolate the high-temperature flame from invading the inside of the line. The raw material of polypropylene is propylene, which is obtained by polymerization to obtain synthetic resin. It is a crystalline polymer, referred to as PP. It has a white waxy appearance, is light and transparent, and polypropylene itself is non-toxic, odorless, has a low density, and its strength, rigidity, hardness and heat resistance are better than low-pressure polyethylene, and can be used at about 100°C. It has the advantages of chemical corrosion resistance, heat resistance, excellent insulation performance and strong plasticity. Polypropylene is commonly used in mechanical parts, corrosion-resistant parts and insulating parts. Common acids such as concentrated phosphoric acid, hydrochloric acid, 40% sulfuric acid and other organic solvents such as salts and alkalis have almost no effect on it, and it can be used for tableware. The mechanical strength of polypropylene is greater than that of polyethylene, and its tensile strength is about 290-380MN / m2. When the temperature exceeds 80℃, its tensile strength decreases relatively little, and even above 100℃, it still retains half of the tensile strength at room temperature. At the same time, compared with the polyethylene process, it not only saves the cross-linking process and degassing process, simplifies the processing technology, reduces costs, and increases production rates, but also compared with the common silane cross-linked polyethylene insulation material, polypropylene has outstanding bending fatigue resistance. The hinge formed with it can be folded and bent 7*107 times without damage or breakage. Its surface hardness is better than that of polyethylene PE, and its surface gloss is excellent. The wear resistance and bending deformation resistance are very good, so polypropylene is known as "low-density high-strength plastic".

[0024] The conductor 1 of the utility model adopts an oxygen-free copper wire core with a copper content of 99.95% and a low resistivity. The structure of the conductor 1 meets the requirements of the first-class solid conductor, the second-class stranded conductor or the fifth-class soft conductor in the GB / 3956 standard. The fire-resistant layer 2 adopts two layers of 0.14mm calcined mica tapes with overlapping wrapping, and the wrapping coverage rate is 25%-30%. As the innermost protective layer, it prevents the flame from burning and causing the wire core to short-circuit or break, which can effectively protect the line and provide more protection for escape or rescue.

[0025] The shielding layer 6 of the utility model adopts oxygen-free copper wire or copper tape. When copper wire braiding shielding is adopted, the braiding density is ≥80%, and the braiding single wire diameter requirement meets the requirements of GB / T 9330 standard. When copper tape shielding is adopted, the copper tape thickness is 0.1mm, the single layer is overlapped and wrapped, and the overlap rate is 15%-20%. The shielding layer 6 has excellent electromagnetic shielding performance, prevents electromagnetic interference from itself and the outside world, and ensures the normal operation of the signal line.

[0026] The oxygen-isolating layer 7 of the utility model adopts ceramic halogen-free low-smoke polyolefin oxygen-isolating material, and the average thickness of the extruded package is controlled at 1.3mm-1.5mm. Under high-temperature flame conditions, the oxygen-isolating layer 7 is crusted and does not drip, forming a dense protective layer, which has the effect of oxygen isolation and heat insulation, and can effectively isolate the high-temperature flame from invading the inside of the cable.

[0027] The armor layer 7 of the utility model adopts hot-dip galvanized double steel belt armoring. The steel belt is required to comply with the GB / T 9330 standard requirements and is used to enhance the tensile strength and compressive strength and protect the internal wire core from damage. Compared with the electro-galvanized steel belt, it has stronger anti-corrosion ability.

[0028] The polyolefin sheath of the utility model adopts B1-level halogen-free, low-smoke, highly flame-retardant polyolefin sheath material, and the extrusion thickness meets the requirements of GB / T 9330. When burning, no halogen acid gas is released, the smoke emission is extremely low, and the crusting performance is excellent, no dripping, protecting the internal wire core structure, non-toxic and environmentally friendly.

[0029] The total thickness of the insulation layer composed of the inner insulation layer and the outer insulation layer remains unchanged. The inner insulation layer and the outer insulation layer are extruded at one time by double-layer co-extrusion, without delamination, and the two layers of insulation cannot be peeled off. The inner insulation layer material has high insulation resistance, good heat resistance, and excellent electrical insulation performance. The design thickness accounts for 30% of the total thickness. The inner insulation ensures the electrical performance of the insulation. The outer insulation layer uses thermoplastic halogen-free low-smoke flame-retardant polyolefin insulation material with high flame retardant performance. Under high temperature or flame conditions, the shell does not crack, melt, or drip. The design thickness accounts for 70% of the total thickness. The production method of double-layer co-extrusion of inner insulation + outer insulation does not change the total insulation thickness, and the manufacturing cost of subsequent processes does not increase. Compared with the common silane cross-linked polyethylene insulation material, it eliminates the cross-linking process and degassing process and improves the production rate. Both polypropylene insulation materials and thermoplastic halogen-free low-smoke flame-retardant polyolefin insulation materials are recyclable and degradable, meeting the development needs of environmentally friendly cable insulation; the inner and outer insulation layers are double-layer co-extruded to simplify the processing technology and reduce costs. Compared with the common silane cross-linked polyethylene insulation materials, the cross-linking and degassing processes are omitted and the production rate is increased; polypropylene insulation materials and thermoplastic halogen-free low-smoke flame-retardant polyolefin insulation materials have high insulation resistance, good flame retardant effect, no dripping when exposed to fire, excellent electrical insulation performance, and good mechanical properties.

[0030] The cable wrapping layer and oxygen-insulating layer are both made of ceramic materials. When exposed to fire, they will form a crust, which has the effect of oxygen-insulating and heat-insulating, and can effectively isolate the high-temperature flame from invading the inside of the cable. The cable is made of materials with excellent anti-drip performance from the inside to the outside. When exposed to flames, it will form a crust by itself without dripping, forming a protective layer by itself, which is oxygen-insulating and heat-insulating, and has excellent flame-retardant properties. The overall structure can meet the requirements of dripping grade d0 in the flame-retardant B1 grade in the standard GB 31247. No halogen gas is released during combustion, and the smoke volume is extremely low, which meets the requirements of environmentally friendly cables.

Claims

1. A new type of anti-drip environmentally friendly cable, Its characteristics are: The invention comprises a plurality of wire cores and a cable wrapping layer (5) wrapping the plurality of wire cores tightly together, wherein the wire core comprises a conductor (1) and a fire-resistant layer (2) wrapped around the outside of the conductor (1) and an insulating layer extruded around the outside of the fire-resistant layer (2), wherein the insulating layer comprises a double-layer co-extruded inner insulating layer (3) and an outer insulating layer (4), wherein the inner insulating layer (3) is a polypropylene insulating layer, and the outer insulating layer (4) is a polyolefin insulating layer, wherein a shielding layer (6) is arranged on the outside of the cable wrapping layer (5), an oxygen-isolating layer (7) is extruded around the outside of the shielding layer (6), an armoring layer (8) is arranged on the outside of the oxygen-isolating layer (7), an outer sheath (9) is extruded around the outer side of the armoring layer (8), and the cable wrapping layer (5) is a ceramic flame-retardant tape.

2. A new type of anti-drip environmentally friendly cable according to claim 1, Its characteristics are: The conductor (1) is an oxygen-free copper wire core with a copper content of 99.95%, and the fire-resistant layer (2) is two layers of calcined mica tapes that are overlapped and wrapped.

3. A new type of anti-drip environmentally friendly cable according to claim 1, Its characteristics are: The thickness of the inner insulating layer (3) accounts for 30% of the total thickness of the insulating layer, and the thickness of the outer insulating layer (4) accounts for 70% of the total thickness of the insulating layer.

4. A new type of anti-drip environmentally friendly cable according to claim 1, Its characteristics are: The shielding layer (6) is woven from oxygen-free copper wires or is formed by overlapping and wrapping a single layer of red copper tape.

5. According to claim 1, a new type of anti-drip environmentally friendly cable, Its characteristics are: The oxygen-isolating layer (7) is a ceramic polyolefin oxygen-isolating layer.

6. A new type of anti-drip environmentally friendly cable according to claim 1, Its characteristics are: The armor layer (8) is composed of two hot-dip galvanized steel strips which are overlapped and wrapped around the outer side of the oxygen-isolating layer (7) with a gap ratio of 40%-50%.

7. A new type of anti-drip environmentally friendly cable according to claim 1, Its characteristics are: The outer protective layer (9) is a polyolefin sheath.

Images