Irradiation crosslinking halogen-free low-smoke flame-retardant fire-resistant cable and production method thereof

Abstract

The invention relates to the technical field of cables, in particular to an irradiation crosslinking halogen-free low-smoke flame-retardant fire-resistant cable and a production method thereof. The cable comprises an insulating wire core, and an inner sheath, an irradiation crosslinking flame-retardant layer, a high-oxygen-index oxygen barrier layer, a halogen-free low-smoke high-flame-retardant belt and an outer sheath which sequentially wrap the outer side of the insulating wire core from inside to outside. The invention aims to provide the irradiation crosslinking halogen-free low-smoke flame-retardant fire-resistant cable so as to solve the problems that an external ceramic material of an existing fire-resistant cable is poor in anti-seismic performance, short in fire-resistant time and poor in fire-resistant performance in a fire disaster; the second purpose of the invention is to provide the production method of the irradiation crosslinking halogen-free low-smoke flame-retardant fire-resistant cable, and the problem that a fire-resistant layer outside the fire-resistant cable is poor in practicability is solved.

Description

Technical Field

[0001] The invention relates to the technical field of cables, and in particular to a radiation cross-linked halogen-free low-smoke flame-retardant and fire-resistant cable and a production method thereof. Background Art

[0002] Power cable refers to the cable used to transmit and distribute electric energy. It is commonly used in urban underground power grids, lead-out lines of power stations, internal power supply of industrial and mining enterprises, and underwater transmission lines across rivers and seas. In power lines, the proportion of cables is gradually increasing. Power cables are cable products used to transmit and distribute high-power electric energy in the main lines of the power system, including 1-500KV and above various voltage levels and various insulation power cables. With the development of science and the progress of society, GB50016-2014 "Code for Fire Protection Design of Buildings" is a mandatory standard issued by the state, requiring that fire emergency equipment in buildings must be equipped with corresponding usage specifications, which requires higher cable requirements.

[0003] The existing fire-resistant cables have complex production processes, high costs, poor flexibility, poor fire resistance at high temperatures, short fire resistance time, and the fire-resistant layer formed by ceramic materials has poor seismic resistance at high temperatures.

[0004] Therefore, how to design a radiation cross-linked halogen-free, low-smoke, flame-retardant and fire-resistant cable and a production method thereof that can solve the above-mentioned technical problems is a technical problem that needs to be solved. Summary of the invention

[0005] In order to solve the above problems, the first object of the present invention is to provide a radiation cross-linked halogen-free low-smoke flame-retardant and fire-resistant cable to solve the problem that the ceramic material on the outside of the existing fire-resistant cable has poor seismic resistance, short fire resistance time and poor fire resistance performance in a fire; the second object of the present invention is to provide a production method of a radiation cross-linked halogen-free low-smoke flame-retardant and fire-resistant cable to solve the problem of poor practicality of the fire-resistant layer on the outside of the fire-resistant cable.

[0006] To achieve the above-mentioned purpose one, the present invention adopts the following technical scheme: comprising an insulating core and an inner sheath, a radiation cross-linked flame retardant layer, a high oxygen index oxygen barrier layer, a halogen-free low smoke high flame retardant tape and an outer sheath sequentially wrapped around the outer side of the insulating core from the inside to the outside;

[0007] The insulating core comprises a conductive core, a conductor shielding layer, an insulating layer and a copper tape shielding layer from the inside to the outside; the insulating core and the inner sheath are filled with alkali-free glass fiber;

[0008] The outer periphery of the copper tape shielding layer is sequentially covered with the inner sheath, the radiation cross-linked flame retardant layer, the high oxygen index oxygen barrier layer, the halogen-free low smoke high flame retardant tape and the outer sheath;

[0009] The insulating wire core is three cores;

[0010] The thickness of the conductor shielding layer is 1.55-1.65 mm;

[0011] The thickness of the insulating layer is 0.81-0.89 mm;

[0012] The thickness of the copper tape shielding layer is 1.1-1.9 mm;

[0013] The thickness of the inner sheath is 1.5-1.7 mm;

[0014] The thickness of the radiation cross-linked flame retardant layer is 0.85-10.0 mm;

[0015] The thickness of the high oxygen index oxygen barrier layer is 2.5-3.5 mm;

[0016] The thickness of the halogen-free, low-smoke, high-flame-retardant tape is 2.0-3.0 mm;

[0017] The thickness of the outer sheath is 1.5-1.7 mm.

[0018] Furthermore, the conductor is made of copper;

[0019] The material of the conductor shielding layer is a semi-conductive material;

[0020] The material of the insulating layer is XLPE;

[0021] The material of the copper tape shielding layer is copper;

[0022] The material of the inner sheath is polytetrafluoroethylene;

[0023] The material of the radiation cross-linked flame retardant layer is radiation cross-linked flame retardant polyolefin;

[0024] The material of the high oxygen index oxygen-isolating layer is a ceramic silicone rubber composite tape;

[0025] The material of the halogen-free, low-smoke, high-flame-retardant tape is low-smoke, halogen-free, flame-retardant material;

[0026] The material of the outer sheath is polyolefin.

[0027] To achieve the above-mentioned second objective, the present invention adopts the following technical solutions:

[0028] Step 1: Extruding a semi-conductive material onto the outer layer of the conductive wire core to form a conductor shielding layer;

[0029] Step 2: continuously extruding an insulating material around the outer periphery of the conductor shielding layer to form an insulating layer;

[0030] Step 3: twist three conductive wire cores covered with a conductor shielding layer, an insulating layer and a copper tape shielding layer into an insulating wire core, and then overlap and wrap the copper tape around the outer periphery of the insulating layer to form a metal shielding layer;

[0031] Step 4: Extruding polytetrafluoroethylene material around the outer periphery of the copper tape shielding layer to form an inner sheath;

[0032] Step 5: Extruding the radiation cross-linked flame retardant polyolefin material on the outer side of the inner sheath to form a radiation cross-linked flame retardant layer;

[0033] Step 6: Extruding the ceramic silicone rubber composite material on the outside of the radiation cross-linked flame retardant layer to form a high oxygen index oxygen barrier layer;

[0034] Step 7: Extruding a low-smoke, halogen-free flame-retardant material on the outside of the high oxygen index oxygen-isolating layer to form a halogen-free, low-smoke, high flame-retardant belt;

[0035] Step 8: Extrude the polyolefin material onto the outer periphery of the halogen-free, low-smoke, high-flame-retardant tape to form an outer sheath.

[0036] Wherein, in step 1, the extrusion is carried out by an extruder;

[0037] Wherein, in step 1, the thickness of the conductor shielding layer is 1.55-1.65 mm.

[0038] Wherein, in step 2, the material of the insulating layer is XLPE;

[0039] Wherein, in step 2, the extrusion is carried out by using an extruder;

[0040] Wherein, in step 2, the extrusion temperature is 480-530°C.

[0041] Wherein, in step 3, the wrapping is performed by overlapping wrapping and the overlap is controlled to be between 10% and 15%;

[0042] Wherein, in step three, the thickness of the copper tape shielding layer is 1.1-1.9 mm.

[0043] Wherein, in step 4, the thickness of the inner sheath is 1.5-1.7 mm;

[0044] Wherein, in step 4, the material of the inner sheath is polytetrafluoroethylene;

[0045] Wherein, in step 4, the extrusion is carried out by tube extrusion.

[0046] Wherein, in step 5, the material of the radiation cross-linked flame retardant layer is radiation cross-linked flame retardant polyolefin;

[0047] Wherein, in step five, the thickness of the radiation cross-linked flame retardant layer is 0.85-10.0 mm.

[0048] Wherein, in step six, the thickness of the radiation cross-linked flame retardant layer is 0.85-10.0 mm;

[0049] Among them, in step six, the extruded package needs to experience temperatures in at least seven temperature zones in sequence, which are 170-175°C, 175-180°C, 180-185°C, 185-190°C, 190-195°C, and 195-200°C.

[0050] Among them, the material of the halogen-free, low-smoke, high-flame-retardant tape is low-smoke, halogen-free, flame-retardant material;

[0051] Wherein, the thickness of the halogen-free, low-smoke, high-flame-retardant tape is 2.0-3.0 mm;

[0052] Wherein, the extrusion is carried out by using a 120 type extruder.

[0053] Wherein, in step eight, the material of the outer sheath is polyolefin;

[0054] Wherein, in step eight, the thickness of the outer sheath is 1.5-1.7 mm.

[0055] The present invention has the following beneficial effects:

[0056] 1. The production process of the radiation cross-linked halogen-free low-smoke flame-retardant and fire-resistant cable of this embodiment is simple, the production efficiency is high, and it is environmentally friendly and economical. The radiation cross-linked flame-retardant layer and the high oxygen index oxygen-isolating layer can effectively organize heat transfer at high temperature, play the role of oxygen isolation, heat insulation and fire protection, have a long irritation time, strong shock resistance, and can ensure integrity and smoothness in the event of a fire.

[0057] 2. In this embodiment, a high oxygen index oxygen-isolating layer is provided. Compared with the performance of ordinary silicone rubber, the high oxygen index oxygen-isolating layer made of a ceramic silicone rubber composite material has the mechanical properties, electrical properties and elasticity of ordinary rubber. In the case of a fire, the peripheral heating will form a hard inorganic support insulating core wire, forming a hard protective layer. The protective layer is a loose porous crust, which can effectively organize heat transfer and play the role of oxygen isolation, heat insulation and fire protection. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Figure 1 It is a schematic diagram of the present invention.

[0059] Description of reference numerals:

[0060] 1-insulated core, 11-conductive core, 12-conductor shield, 13-insulating layer, 14-copper tape shield;

[0061] 2-Inner sheath;

[0062] 3- irradiation cross-linked flame retardant layer;

[0063] 4-High oxygen index oxygen barrier layer;

[0064] 5-Halogen-free, low-smoke, high flame retardant tape;

[0065] 6- Outer sheath. DETAILED DESCRIPTION

[0066] Embodiment 1

[0067] It comprises an insulated wire core 1 and an inner sheath 2, a radiation cross-linked flame retardant layer 3, a high oxygen index oxygen barrier layer 4, a halogen-free low smoke high flame retardant tape 5 and an outer sheath 6 which are sequentially wrapped around the outer side of the insulated wire core 1 from the inside to the outside;

[0068] The insulating core 1 comprises a conductive core 11, a conductor shielding layer 12, an insulating layer 13 and a copper tape shielding layer 14 from the inside to the outside; the insulating core 1 and the inner sheath 2 are filled with alkali-free glass fiber;

[0069] The outer periphery of the copper tape shielding layer 14 is sequentially covered with the inner sheath 2, the radiation cross-linked flame retardant layer 3, the high oxygen index oxygen barrier layer 4, the halogen-free low smoke high flame retardant tape 5 and the outer sheath 6;

[0070] The insulating wire core is three cores;

[0071] The conductor is made of copper;

[0072] The material of the conductor shielding layer 12 is a semi-conductive material;

[0073] The material of the insulating layer 13 is XLPE;

[0074] The material of the copper tape shielding layer 14 is copper;

[0075] The material of the inner sheath 2 is polytetrafluoroethylene;

[0076] The material of the radiation cross-linked flame retardant layer 3 is radiation cross-linked flame retardant polyolefin;

[0077] The material of the high oxygen index oxygen-isolating layer 4 is a ceramic silicone rubber composite tape;

[0078] The material of the halogen-free, low-smoke, high-flame-retardant belt 5 is a low-smoke, halogen-free, flame-retardant material;

[0079] The material of the outer sheath 6 is polyolefin;

[0080] The preparation method of this embodiment comprises the following steps:

[0081] Step 1: Extruding a semi-conductive material on the outer layer of the conductive wire core 11 to form a conductor shielding layer 12, wherein the thickness of the conductor shielding layer 12 is 1.55-1.65 mm;

[0082] Step 2: continuously extruding the insulating material around the conductor shielding layer 12 to form an insulating layer 13; the thickness of the insulating layer 13 is 0.81-0.89 mm;

[0083] Step 3: Twisting three conductive wire cores 11 covered with a conductor shielding layer 12, an insulating layer 13 and a copper tape shielding layer 14 into an insulating wire core 1, and then wrapping the copper tape around the outer periphery of the insulating layer 13 to form a metal shielding layer; the thickness of the copper tape shielding layer 14 is 1.1-1.9 mm;

[0084] Step 4: using a tube extrusion method to continuously extrude polytetrafluoroethylene around the outer periphery of the metal shielding layer to form an inner sheath 2; the thickness of the inner sheath 2 is 1.5-1.7 mm;

[0085] Step 5: Extruding the radiation cross-linked flame-retardant polyolefin material on the outside of the inner sheath 2 to form a radiation cross-linked flame-retardant layer 3; the thickness of the radiation cross-linked flame-retardant layer 3 is 0.85-10.0 mm; wherein the extrusion needs to experience at least seven temperature zones in sequence, which are 170-175°C, 175-180°C, 180-185°C, 185-190°C, 190-195°C, and 195-200°C respectively.

[0086] Step six: Extruding the ceramic silicone rubber composite material on the outside of the radiation cross-linked flame retardant layer 3 to form a high oxygen index oxygen-isolating layer 4; the thickness of the high oxygen index oxygen-isolating layer 4 is 2.5-3.5 mm;.

[0087] Step 7: Use a 120-type extruder to extrude the low-smoke halogen-free flame-retardant material onto the outside of the galvanized steel wire outer layer to form a halogen-free, low-smoke, high-flame-retardant belt 5, wherein the thickness of the halogen-free, low-smoke, high-flame-retardant belt 5 is 2.0-3.0 mm.

[0088] Step eight: extruding a polyolefin material around the periphery of the halogen-free, low-smoke, high-flame-retardant tape 5 to form an outer sheath 6 , wherein the thickness of the outer sheath 67 is 1.5-1.7 mm.

[0089] The radiation cross-linked halogen-free low-smoke flame-retardant and fire-resistant cable of this embodiment has a simple production process, high production efficiency, environmental protection and economy. The radiation cross-linked flame-retardant layer 3 and the high oxygen index oxygen-isolating layer 4 can effectively organize heat transfer at high temperature, play the role of oxygen isolation, heat insulation and fire protection, have a long irritation time, strong shock resistance, and can ensure integrity and smoothness in fire.

[0090] Embodiment 2

[0091] To achieve the above-mentioned second objective, the present invention adopts the following technical solutions:

[0092] Step 1: Extruding a semi-conductive material on the outer layer of the conductive wire core 11 to form a conductor shielding layer 12;

[0093] Step 2: continuously extruding the insulating material around the outer periphery of the conductor shielding layer 12 to form an insulating layer 13;

[0094] Step 3: Twisting three conductive wire cores 11 covered with a conductor shielding layer 12, an insulating layer 13 and a copper tape shielding layer 14 into an insulating wire core 1, and then overlapping and wrapping the copper tape around the outer periphery of the insulating layer 13 to form a metal shielding layer;

[0095] Step 4: Extruding polytetrafluoroethylene material around the outer periphery of the copper tape shielding layer 14 to form an inner sheath 2;

[0096] Step 5: Extruding the radiation cross-linked flame retardant polyolefin material on the outer side of the inner sheath 2 to form a radiation cross-linked flame retardant layer 3;

[0097] Step 6: Extruding the ceramic silicone rubber composite material on the outside of the radiation cross-linked flame retardant layer 3 to form a high oxygen index oxygen barrier layer 4;

[0098] Step 7: Extruding a low-smoke, halogen-free flame-retardant material on the outside of the high oxygen index oxygen-isolating layer 4 to form a halogen-free, low-smoke, high flame-retardant belt 5;

[0099] Step eight: extruding a polyolefin material onto the outer periphery of the halogen-free, low-smoke, high-flame-retardant tape 5 to form an outer sheath 6 .

[0100] Wherein, in step 1, the extrusion is carried out by an extruder;

[0101] Wherein, in step 1, the thickness of the conductor shielding layer 12 is 1.55-1.65 mm.

[0102] Wherein, in step 2, the material of the insulating layer 13 is XLPE;

[0103] Wherein, in step 2, the extrusion is carried out by using an extruder;

[0104] Wherein, in step 2, the extrusion temperature is 480-530°C.

[0105] Wherein, in step 3, the wrapping is performed by overlapping wrapping and the overlap is controlled to be between 10% and 15%;

[0106] Wherein, in step three, the thickness of the copper tape shielding layer 14 is 1.1-1.9 mm.

[0107] Wherein, in step 4, the thickness of the inner sheath 2 is 1.5-1.7 mm;

[0108] Wherein, in step 4, the material of the inner sheath 2 is polytetrafluoroethylene;

[0109] Wherein, in step 4, the extrusion is carried out by tube extrusion.

[0110] Wherein, in step 5, the material of the radiation cross-linked flame retardant layer 3 is radiation cross-linked flame retardant polyolefin;

[0111] Wherein, in step five, the thickness of the radiation cross-linked flame retardant layer 3 is 0.85-10.0 mm.

[0112] Wherein, in step six, the thickness of the radiation cross-linked flame retardant layer 3 is 0.85-10.0 mm;

[0113] Among them, in step six, the extruded package needs to experience temperatures in at least seven temperature zones in sequence, which are 170-175°C, 175-180°C, 180-185°C, 185-190°C, 190-195°C, and 195-200°C.

[0114] Among them, the material of the halogen-free, low-smoke, high-flame-retardant belt 5 is a low-smoke, halogen-free, flame-retardant material;

[0115] Wherein, the thickness of the halogen-free, low-smoke, high-flame-retardant tape 5 is 2.0-3.0 mm;

[0116] Wherein, the extrusion is carried out by using a 120 type extruder.

[0117] Wherein, in step eight, the material of the outer sheath 6 is polyolefin;

[0118] Wherein, in step eight, the thickness of the outer sheath 6 is 1.5-1.7 mm.

[0119] The above description is only a specific implementation mode of the present invention, and does not limit the patent scope of the present invention. Any equivalent structural transformation made by using the contents of the present invention description and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. An irradiated cross-linked halogen-free low-smoke flame-retardant and fire-resistant cable, characterized in that: It comprises an insulating wire core (1), and an inner sheath (2), a radiation cross-linked flame retardant layer (3), a high oxygen index oxygen barrier layer (4), a halogen-free low smoke high flame retardant tape (5), and an outer sheath (6) which are sequentially wrapped around the outer side of the insulating wire core (1) from the inside to the outside; The insulating wire core (1) comprises, from the inside to the outside, a conductive wire core (11), a conductor shielding layer (12), an insulating layer (13) and a copper tape shielding layer (14); alkali-free glass fiber is filled between the insulating wire core (1) and the inner sheath (2); The outer periphery of the copper tape shielding layer (14) is sequentially coated with the inner sheath (2), the radiation cross-linked flame retardant layer (3), the high oxygen index oxygen barrier layer (4), the halogen-free low smoke high flame retardant tape (5) and the outer sheath (6); The insulating wire core is three cores; The thickness of the conductor shielding layer (12) is 1.55-1.65 mm; The thickness of the insulating layer (13) is 0.81-0.89 mm; The thickness of the copper tape shielding layer (14) is 1.1-1.9 mm; The thickness of the inner sheath (2) is 1.5-1.7 mm; The thickness of the radiation cross-linked flame retardant layer (3) is 0.85-10.0 mm; The thickness of the high oxygen index oxygen-isolating layer (4) is 2.5-3.5 mm; The thickness of the halogen-free, low-smoke, high-flame-retardant tape (5) is 2.0-3.0 mm; The thickness of the outer sheath (6) is 1.5-1.7 mm.

2. A low-smoke, halogen-free, flame-retardant and fire-resistant cable according to claim 1, characterized in that: the conductor is made of copper; The material of the conductor shielding layer (12) is a semi-conductive material; The material of the insulating layer (13) is XLPE; The material of the copper tape shielding layer (14) is copper; The inner sheath (2) is made of polytetrafluoroethylene; The material of the radiation cross-linked flame retardant layer (3) is radiation cross-linked flame retardant polyolefin; The material of the high oxygen index oxygen-isolating layer (4) is a ceramic silicone rubber composite tape; The material of the halogen-free, low-smoke, highly flame-retardant belt (5) is a low-smoke, halogen-free, flame-retardant material.

3. A method for producing a radiation cross-linked halogen-free, low-smoke, flame-retardant and fire-resistant cable according to any one of claims 1 to 2, characterized in that: It includes the following steps: Step 1: Extruding a semi-conductive material onto the outer layer of the conductive wire core (11) to form a conductor shielding layer (12); Step 2: continuously extruding an insulating material around the outer periphery of the conductor shielding layer (12) to form an insulating layer (13); Step 3: Twisting three conductive wire cores (11) coated with a conductor shielding layer (12), an insulating layer (13) and a copper tape shielding layer (14) into an insulating wire core (1), and then wrapping a copper tape around the outer periphery of the insulating layer (13) to form a metal shielding layer; Step 4: Extruding a polytetrafluoroethylene material around the outer periphery of the copper tape shielding layer (14) to form an inner sheath (2); Step 5: Extruding a radiation cross-linked flame retardant polyolefin material onto the outer side of the inner sheath (2) to form a radiation cross-linked flame retardant layer (3); Step 6: Extruding the ceramic silicone rubber composite material onto the outside of the radiation cross-linked flame retardant layer (3) to form a high oxygen index oxygen barrier layer (4); Step 7: Extruding a low-smoke, halogen-free flame-retardant material onto the outer side of the high oxygen index oxygen-isolating layer (4) to form a halogen-free, low-smoke, high flame-retardant belt (5); Step 8: Extruding a polyolefin material onto the outer periphery of the halogen-free, low-smoke, high-flame-retardant tape (5) to form an outer sheath (6).

4. The method for producing a low-smoke, halogen-free, flame-retardant and fire-resistant cable according to claim 3, characterized in that: In step 1, the extrusion is carried out by an extruder; In step 1, the thickness of the conductor shielding layer (12) is 1.55-1.65 mm.

5. The method for producing a low-smoke, halogen-free, flame-retardant and fire-resistant cable according to claim 3, characterized in that: In step 2, the material of the insulating layer (13) is XLPE; In step 2, the extrusion is performed using an extruder; In step 2, the extrusion temperature is 480-530°C.

6. The method for producing a low-smoke, halogen-free, flame-retardant and fire-resistant cable according to claim 3, characterized in that: In step 3, the wrapping is performed by overlapping wrapping and the overlap is controlled to be between 10% and 15%; In step three, the thickness of the copper tape shielding layer (14) is 1.1-1.9 mm.

7. The method for producing a low-smoke, halogen-free, flame-retardant and fire-resistant cable according to claim 3, characterized in that: In step 4, the thickness of the inner sheath (2) is 1.5-1.7 mm; In step 4, the material of the inner sheath (2) is polytetrafluoroethylene; In step 4, the extrusion is performed by tube extrusion.

8. The method for producing a low-smoke, halogen-free, flame-retardant and fire-resistant cable according to claim 3, characterized in that: In step 5, the material of the radiation cross-linked flame retardant layer (3) is radiation cross-linked flame retardant polyolefin; In step five, the thickness of the radiation cross-linked flame retardant layer (3) is 0.85-10.0 mm.

9. The method for producing a low-smoke, halogen-free, flame-retardant and fire-resistant cable according to claim 3, characterized in that: In step six, the thickness of the radiation cross-linked flame retardant layer (3) is 0.85-10.0 mm; In step six, the extruded package needs to sequentially experience temperatures in at least seven temperature zones, namely 170-175°C, 175-180°C, 180-185°C, 185-190°C, 190-195°C, and 195-200°C.

10. The method for producing a low-smoke, halogen-free, flame-retardant and fire-resistant cable according to claim 3, characterized in that: In step 7, the material of the halogen-free, low-smoke, highly flame-retardant tape (5) is a low-smoke, halogen-free, flame-retardant material; In step 7, the thickness of the halogen-free, low-smoke, high-flame-retardant tape (5) is 2.0-3.0 mm; In step seven, the extrusion is carried out using a 120-type extruder. In step eight, the material of the outer sheath (6) is polyolefin; In step eight, the thickness of the outer sheath (6) is 1.5-1.7 mm.

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