Fire-resistant cable suitable for building fire heating condition and manufacturing method thereof

Abstract

The invention belongs to the technical field of fire-resistant cables, and provides a fire-resistant cable suitable for building fire heating conditions and a manufacturing method thereof, a fire-resistant layer is an inorganic mineral insulating tape, an insulating layer and a fire insulation layer are made of a ceramic polyolefin material, a liner layer is a ceramic fireproof fire-resistant composite tape, and the liner layer is made of a ceramic polyolefin material. The sheath layer is made of a halogen-free low-smoke flame-retardant polyolefin sheath material; the fireproof layer and the insulating layer form composite insulation, so that high electrical insulation performance can be kept under long-time flame and high-temperature conditions; the insulation layer, the liner layer and the fire insulation layer are designed to form a triple fire insulation and heat insulation structure, so that the cable can continuously and stably operate in a fire environment with continuously increased temperature, and the cable is suitable for the fire environment and gains time for rescue and escape; and on the basis of simplifying the layer number of the structure, the mechanical property, the processability, the flexibility and the fire resistance are considered.

Description

Technical Field

[0001] The invention belongs to the technical field of fire-resistant cables and relates to a fire-resistant cable suitable for use under temperature-raising conditions of building fires and a manufacturing method thereof. Background Art

[0002] Fire-resistant cables are mainly used in crowded places such as buildings, shopping malls, supermarkets, hospitals, theaters, subways and airports, as well as important engineering facilities in special fields such as petrochemicals, metallurgy and steel. These engineering facilities have high requirements for power transmission and are in special environments such as high temperature and high pressure, which have high requirements for safety. Therefore, fire-resistant cables are needed to ensure the reliability and safety of power transmission.

[0003] The inventors found that fire-resistant cables are tested before leaving the factory, but the current fire resistance test method cannot reflect the actual fire situation, resulting in the fire-resistant cables leaving the factory not being able to perform well in a fire; this is mainly manifested in that traditional fire-resistant cables are equipped with mica tape insulation layers, rubber-plastic outer sheaths, etc., which have improved the fire resistance to a certain extent, but in a fire environment, the flame will completely wrap the cable, the flame temperature and ambient temperature can reach above 1000°C, and a large fire can last for several hours or even more than ten hours. Traditional fire-resistant cables will lose their fire resistance in a relatively short period of time in a long-term, high-temperature fire environment, and the cables may even spontaneously combust and support combustion, increasing the fire and smoke, and increasing the degree of personal injury. Summary of the invention

[0004] In order to solve the above problems, the present invention proposes a fire-resistant cable suitable for building fire temperature rising conditions and its manufacturing method. The fire-resistant cable in the present invention includes a conductor, and a fire-resistant layer, an insulating layer, a cushion layer, a fire-proof layer and a sheath layer arranged on the outside of the conductor in sequence; wherein the fire-resistant layer is an inorganic mineral insulating tape, the insulating layer and the fire-proof layer are ceramic polyolefin materials, the cushion layer is a ceramic fire-proof and fire-resistant composite tape, and the sheath layer is a halogen-free low-smoke flame-retardant polyolefin sheath material; the composite insulation is formed by the fire-resistant layer and the insulating layer, which can maintain high electrical insulation performance under long-term flame and high temperature conditions; the insulating layer, the cushion layer, and the fire-proof layer form a triple fire-proof and heat-insulating structure design, which ensures that the cable can operate continuously and stably in a fire environment with a continuously rising temperature, and is suitable for a fire environment to win time for rescue and escape; and on the basis of simplifying the number of structural layers, it takes into account mechanical properties, processing properties, flexibility and fire resistance.

[0005] In order to achieve the above-mentioned object, in a first aspect, the present invention provides a fire-resistant cable suitable for use under the temperature rise conditions of a building fire, adopting the following technical solution:

[0006] A fire-resistant cable suitable for use under temperature-raising conditions of building fires, comprising a conductor, and a fire-resistant layer, an insulating layer, a lining layer, a fire-proof layer and a sheath layer sequentially arranged outside the conductor;

[0007] The fire-resistant layer is an inorganic mineral insulating tape, the insulating layer and the fire-proof layer are ceramic polyolefin materials, the cushion layer is a ceramic fire-proof and fire-resistant composite tape, and the sheath layer is a halogen-free, low-smoke, flame-retardant polyolefin sheath material.

[0008] Furthermore, the ceramic polyolefin material is composed of the following parts by weight: 100-140 parts of polyolefin resin, 100-120 parts of ceramic rubber, 60-80 parts of inorganic filler, 0.5-5 parts of lubricant, 1-5 parts of antioxidant, 0.1-5 parts of coupling agent, 3-10 parts of compatibilizer, 1-20 parts of promoter, 0.3-3 parts of thermal sensitizer, 0.1-2 parts of stabilizer, and 0.5-2.5 parts of processing aid.

[0009] Furthermore, the ceramic rubber material is a mixture of thermoplastic silicone resin and silicon dioxide prepared by vapor deposition method.

[0010] Furthermore, the conductor is a copper conductor.

[0011] In order to achieve the above-mentioned object, in a second aspect, the present invention also provides a method for manufacturing a fire-resistant cable suitable for use under temperature rise conditions of a building fire, which adopts the following technical solution:

[0012] A method for manufacturing a fire-resistant cable suitable for use under temperature rise conditions of a building fire, for manufacturing the fire-resistant cable suitable for use under temperature rise conditions of a building fire as described in the first aspect, comprising:

[0013] An inorganic mineral insulating tape is wrapped around the surface of the conductor to form a fire-resistant layer, a ceramic polyolefin material is extruded on the surface of the fire-resistant layer to form an insulating layer, the insulating cores of the multi-core cable should be twisted into a cable core, a tape is wrapped around the insulating core of the single-core cable or the cable core of the multi-core cable to form a cushioning layer, a ceramic polyolefin material is extrude outside the cushioning layer to form a fire-proof layer, and a halogen-free, low-smoke, flame-retardant polyolefin sheath material is extruded outside the fire-proof layer to form a sheathing layer.

[0014] Further, preparing thermoplastic silicone resin, synthesizing thermoplastic silicone resin;

[0015] The synthesized thermoplastic silicone resin is put into a three-roll mill for grinding to obtain a ceramic rubber compound;

[0016] The ceramicized rubber material is put into a twin-screw extruder for extrusion granulation to obtain a ceramicized polyolefin material;

[0017] The soft copper wires are twisted in a regular arrangement on a frame twisting machine to form a twisted conductor; an inorganic mineral insulating tape is wrapped around the surface of the twisted conductor to form a fire-resistant layer, the inorganic mineral insulating tape should be wrapped in an overlapping manner, the wrapping direction of each layer should be opposite, and the outermost layer is to the right, so as to obtain a fire-resistant conductor; a ceramicized polyolefin material is extruded on the surface of the fire-resistant conductor to form an insulating layer, so as to obtain an insulated wire core; a color ribbon is added to the insulating layer during extrusion, and the colors of the insulated wire core are identified according to yellow, green, red, blue and black color matching;

[0018] Arrange the insulated wire cores in the order of yellow, green, red, blue and black in a clockwise direction and twist them into a cable core on a cabling machine; fill the gaps between the insulated wire cores of the cable core with inorganic fibers; wrap the cable core around and tighten it to form a cushion layer, and the wrapping tape is a ceramic fire-resistant composite tape;

[0019] Extruding ceramic polyolefin material outside the cushion layer to form a fire-insulating layer; the fire-insulating layer should be extruded to form a preset thickness;

[0020] A layer of halogen-free, low-smoke, flame-retardant polyolefin sheath material is extruded outside the fire-insulating layer to form a sheath layer.

[0021] Further, the organosilane monomer is reacted at 30-35° C. for 10-11 hours according to an acid-catalyzed alcohol hydrolysis process; the reaction system is heated to 71-75° C. and condensed under vacuum for 2 hours; the reaction system is heated to 145-150° C. and reacted at a pressure of 0.01-0.02 MPa for 1.5-2 hours to obtain a colorless viscous liquid, which is cooled to room temperature to obtain a thermoplastic silicone resin.

[0022] Furthermore, the synthesized thermoplastic silicone resin is put into a three-roll mill for grinding, and silicon dioxide prepared by a vapor deposition method is added, mixed and stirred evenly, and then discharged to obtain a ceramic rubber compound.

[0023] Furthermore, the prepared ceramic rubber, polyolefin resin, inorganic filler, stabilizer, processing aid and heat sensitizer are put into a twin-screw extruder for extrusion granulation to prepare a ceramic polyolefin material.

[0024] Further, the polyolefin resin, ceramic rubber, inorganic filler, accelerator, lubricant, antioxidant, coupling agent, compatibilizer, heat sensitizer, stabilizer and processing aid are picked up according to a preset ratio, put into a mixer for thorough mixing, the speed of the mixer is controlled to be 300-350 rpm, and the mixing time is 15-20 minutes;

[0025] Debug the temperature of each zone of the twin-screw extruder granulator. The reference temperature is set as follows: 90-110℃ for barrel zone 1, 150-155℃ for barrel zone 2, 165-170℃ for barrel zone 3, 185-190℃ for barrel zone 4, 180-185℃ for barrel zone 5, 175-180℃ for die head, and 175-180℃ for mold. The twin-screw granulator needs to run at no load for 5-10 minutes based on the reference temperature, then pour the mixed material into the granulator, and the extrudate from the granulator enters the cooling pool for cooling;

[0026] The cooled extrudate is air-cooled to blow away the moisture on the surface, and then enters the pelletizer to be sheared into particles;

[0027] The cooled particles are transported to the dryer for particle drying and water removal. The temperature of the dryer is 65-70°C and the drying time is 1-3 hours.

[0028] The dried particles need to be stored in a sealed container.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] The fire-resistant cable in the present invention comprises a conductor, and a fire-resistant layer, an insulating layer, a cushion layer, a fire-proof layer and a sheath layer which are sequentially arranged outside the conductor; wherein the fire-resistant layer is an inorganic mineral insulating tape, the insulating layer and the fire-proof layer are ceramic polyolefin materials, the cushion layer is a ceramic fire-proof and fire-resistant composite tape, and the sheath layer is a halogen-free low-smoke flame-retardant polyolefin sheath material; the composite insulation is formed by the fire-resistant layer and the insulating layer, which can maintain high electrical insulation performance under long-term flame and high temperature conditions; the insulating layer, the cushion layer and the fire-proof layer form a triple fire-proof and heat-insulating structural design, which ensures that the cable can operate continuously and stably in a fire environment with continuously rising temperatures, is suitable for use in a fire environment, and wins time for rescue and escape; and on the basis of simplifying the number of structural layers, it takes into account mechanical properties, processing properties, flexibility and fire resistance.

[0031] The present invention adopts a triple fireproof and heat-insulating structural design. The insulating layer and the fireproof layer are made of ceramic polyolefin material, and the cushion layer is made of ceramic fireproof and fire-resistant composite tape. These two materials can be sintered into a ceramic shell after flame ablation, which blocks the flame and heat from spreading to the inside of the cable and protects the internal structure. The fire-resistant layer and the insulating layer form composite insulation, which improves the electrical insulation performance of the cable under flame conditions. Since no fireproof mud material and metal sheath layer are used, the flexibility of the cable is improved, and the bending performance of the finished cable is improved. A large amount of flame-retardant materials are used in the cable, which improves the flame-retardant performance of the cable. In an exogenous fire, the cable does not spontaneously combust or support combustion, which can reduce the fire and smoke and reduce personal injury. In the present invention, the fire-resistant layer adopts an inorganic mineral insulating tape, the insulating layer adopts an extruded ceramic polyolefin material, the fire-resistant layer and the insulating layer constitute a composite insulation, and both are high-temperature resistant materials, which can maintain high electrical insulation performance under flame and high temperature conditions; the cushion layer adopts a ceramic fire-proof and fire-resistant composite tape, the fire-insulating layer adopts an extruded ceramic polyolefin material, and the sheath layer adopts a halogen-free, low-smoke, flame-retardant polyolefin material with good crusting performance; the ceramic fire-proof and fire-resistant composite tape and the ceramic polyolefin material have excellent high-temperature resistance, and form a hard ceramic layer when heat and flame burn, which isolates the flame and heat from transmitting to the inside of the cable, and plays a role in fire insulation and heat insulation; the triple fire insulation and heat insulation structure design of the insulating layer, the cushion layer and the fire insulation layer ensures that the cable can operate continuously and stably in a fire environment with continuously rising temperatures, thereby buying time for rescue and escape.

[0032] The ceramic polyolefin material of the present invention comprises, by weight, 100 to 140 parts of polyolefin resin, 100 to 120 parts of ceramic rubber, 60 to 80 parts of inorganic filler, 0.5 to 5 parts of lubricant, 1 to 5 parts of antioxidant, 0.1 to 5 parts of coupling agent, 3 to 10 parts of compatibilizer, 1 to 20 parts of accelerator, 0.3 to 3 parts of thermal sensitizer, 0.1 to 2 parts of stabilizer and 0.5 to 2.5 parts of processing aid. The ceramic polyolefin material is designed so that the insulation layer and the fireproof layer have good electrical properties, mechanical properties, processing properties, flexibility and fire resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The drawings in the specification that constitute a part of this embodiment are used to provide a further understanding of this embodiment. The schematic embodiments of this embodiment and their descriptions are used to explain this embodiment and do not constitute improper limitations on this embodiment.

[0034] Figure 1 This is a schematic diagram of the structure of a single-core cable according to Embodiment 1 of the present invention;

[0035] Figure 2 This is a schematic diagram of the structure of a multi-core cable according to Embodiment 2 of the present invention;

[0036] Among them, 1. Conductor; 2. Fire-resistant layer; 3. Insulation layer; 4. Filler; 5. Cushioning layer; 6. Fire-proof layer; 7. Sheath layer. DETAILED DESCRIPTION

[0037] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0038] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.

[0039] Embodiment 1:

[0040] With the frequent occurrence of various fire accidents, huge losses of life and property have been caused, so the requirements for fire-resistant cables used in fire protection systems are constantly increasing. Fire-resistant cables are mainly used in crowded places such as buildings, shopping malls, supermarkets, hospitals, theaters, subways, airports, and important engineering facilities with special requirements such as petrochemicals, metallurgy, and steel. These engineering facilities have high requirements for power transmission, and are in special environments such as high temperature and high pressure, which have high requirements for safety. Therefore, fire-resistant cables are needed to ensure the reliability and safety of power transmission.

[0041] Fire-resistant cables are tested before leaving the factory. However, the current fire-resistant test method cannot reflect the actual fire situation, resulting in that the fire-resistant cables leaving the factory cannot function well. This is mainly manifested in the following aspects: the cables in the fire-resistant test are arranged horizontally as a single cable, while the actual cables are mostly laid horizontally or vertically in bundles; the fire-resistant test uses a single blowtorch with a length of 500mm and a flame temperature of 750℃. The length area of ​​the cable ablated is limited. For cables with large outer diameters, the flame cannot wrap around the cable and can only ablate the bottom of the cable; while in a fire, the flame will completely wrap around the cable, similar to heating with multiple blowtorches. The temperature can reach over 1000℃; the fire resistance test time is 90min, while a large fire can last for several hours or even more than ten hours; the starting ambient temperature of the fire resistance test is room temperature, and the ambient temperature is heated by the heat of the test flame, and the ambient temperature is less than 100℃ at the end of the test; and from the perspective of the fire development process, the fire changes with time, and the fire will change with the changes in the fire load, nature and distribution, and the ambient temperature will continue to rise with the development of the fire. Fire science research shows that when the fire reaches 180min, the ambient temperature can exceed 1000℃. These differences have led to the current fire-resistant cables not being able to play a good role in actual fires, losing the original intention of fire-resistant cables.

[0042] In summary, as recorded in the background technology, traditional fire-resistant cables are equipped with mica tape insulation layers, rubber and plastic outer sheaths, etc. Although they have improved the fire resistance to a certain extent, the cables cannot function well in a long-term, high-temperature fire environment and will lose their fire resistance in a relatively short period of time. The cables may even spontaneously combust and support combustion, increasing the fire and smoke and the degree of personal injury.

[0043] In order to solve the above problems, Figure 1 As shown, this embodiment provides a fire-resistant cable suitable for use under temperature-raising conditions of building fires, the cable is a single-core cable, the cable comprises a conductor 1 arranged from the inside to the outside, a fire-resistant layer 2 wrapped flatly and densely on the conductor 1, an insulating layer 3 extruded on the fire-resistant layer 2, a cushioning layer 5 formed by a ceramic fire-resistant composite tape wrapped outside the insulating layer 3, a fire-insulating layer 6 formed by extruding a ceramic polyolefin material outside the cushioning layer 5, and a sheath layer 7 formed by a halogen-free, low-smoke, flame-retardant polyolefin material with good shelling performance extruded outside the fire-insulating layer 6; the cable as a whole achieves fire-resistant, flame-retardant and other properties.

[0044] The conductor 1 is a copper conductor; the conductor 1 is formed by twisting a plurality of thin copper wires. The fire-resistant layer 2 is a mica tape or a ceramic fire-resistant mica tape or a composite structure. The insulating layer 3 is a ceramic polyolefin material.

[0045] The weight composition of the ceramic polyolefin material is as follows: 100-140 parts of polyolefin resin, 100-120 parts of ceramic rubber, 60-80 parts of inorganic filler, 0.5-5 parts of lubricant, 1-5 parts of antioxidant, 0.1-5 parts of coupling agent, 3-10 parts of compatibilizer, 1-20 parts of promoter, 0.3-3 parts of thermal sensitizer, 0.1-2 parts of stabilizer, 0.5-2.5 parts of processing aid; wherein, the ceramic rubber is a mixture of thermoplastic silicone resin and silicon dioxide prepared by vapor deposition. In some embodiments, the cable made of the ceramic polyolefin material of the above weight group and the cable made of the ceramic polyolefin material of the traditional weight composition are compared in a simulated real building fire environment. It can be proved that the insulating layer 3 and the fire barrier layer 6 in this embodiment have good mechanical properties, processing properties, flexibility and fire resistance.

[0046] In order to obtain the fire-resistant cable in this embodiment, this embodiment also provides a method for manufacturing the cable, and the optional steps may include:

[0047] S1. Preparation of ceramic polyolefin materials:

[0048] S1.1, preparation of thermoplastic silicone resin:

[0049] S1.1.1. The organosilane monomer is reacted at 30-35°C for 10-11 hours according to the acid-catalyzed alcohol hydrolysis process.

[0050] S1.1.2. Heat the reaction system to 71-75°C and carry out condensation reaction under vacuum for about 2 hours.

[0051] S1.1.3. Heat the reaction system to 145-150°C and continue the reaction at a pressure of 0.01-0.02 MPa for 1.5-2 hours. The obtained product is a colorless viscous liquid. After cooling to room temperature, it becomes a white hard solid, which is a thermoplastic silicone resin.

[0052] S1.2, preparation of ceramic rubber:

[0053] The thermoplastic silicone resin synthesized in step S1.1 is put into a three-roll mill for grinding, and silicon dioxide prepared by vapor deposition is added, mixed and stirred evenly, and then discharged to obtain a ceramic rubber material.

[0054] S1.3, preparation of ceramic polyolefin material:

[0055] The ceramicized rubber obtained in step S1.2 and a preset ratio of polyolefin resin, inorganic filler, stabilizer, processing aid and thermal sensitizer are put into a twin-screw extruder for extrusion granulation to obtain a ceramicized polyolefin material; the preset ratio can adopt a conventional ratio, or a ratio obtained by experimental comparison, which will not be described in detail here.

[0056] S1.3.1. Pick up the polyolefin resin, ceramic rubber, inorganic filler, accelerator, lubricant, antioxidant, coupling agent, compatibilizer, heat sensitizer, stabilizer and processing aid in the formula according to the set ratio, put them into the mixer for thorough mixing, at this time, the speed of the mixer needs to be controlled to 300-350rpm, and the mixing time is 15-20 minutes. The preset ratio can adopt the conventional ratio, or the ratio obtained by experimental comparison, which will not be described in detail here.

[0057] S1.3.2. Adjust the temperature of each zone of the twin-screw extruder granulator. The reference temperature is set as follows: barrel zone 1 90-110℃, barrel zone 2 150-155℃, barrel zone 3 165-170℃, barrel zone 4 185-190℃, barrel zone 5 180-185℃, die head 175-180℃, and mold 175-180℃. The twin-screw granulator needs to run at no load for 5-10 minutes based on the reference temperature, then pour the mixed material into the granulator, and the extrudate from the granulator must immediately enter the cooling pool for cooling. Note that the cooling pool needs to continuously circulate water and be equipped with an impurity treatment device to keep the water clean.

[0058] S1.3.3. The cooled extrudate is air-cooled to blow away the moisture on the surface, and then enters the pelletizer to be sheared into granules.

[0059] S1.3.4. The cooled particles are transferred from the equipment to the dryer for particle drying and water removal. The reference temperature of the dryer is 65-70°C and the reference drying time is 1-3 hours.

[0060] S1.3.5 The dried particles must be stored in a sealed container to prevent them from absorbing water and getting damp.

[0061] S1.3.6. Check the quality of finished granules in each batch and require that the finished granules meet the qualified technical requirements.

[0062] S2. Cable manufacturing:

[0063] S2.1. Twist the soft copper wires in a regular arrangement on a frame stranding machine to form a stranded conductor 1; wrap an inorganic mineral insulating tape on the surface of the stranded conductor to form a fire-resistant layer 2. The inorganic mineral insulating tape should be wrapped in an overlapping manner, and the wrapping direction of each layer should be opposite, with the outermost layer facing right, to obtain a fire-resistant conductor; extrude a ceramicized polyolefin material on the surface of the fire-resistant layer to form an insulating layer 3, to obtain an insulated wire core.

[0064] S2.2. Wrap a tape around the insulated wire core and tie it tightly to form a cushion layer 5. The tape should be a ceramic fire-proof and fire-resistant composite tape.

[0065] S2.3, extrude ceramic polyolefin material outside the cushion layer to form a fire-insulating layer 6. The fire-insulating layer should be extruded to form a certain thickness, and can form a ceramic shell under flame erosion, and adhere to the surface of the cable core without falling off.

[0066] S2.4. Extrude a layer of orange-red halogen-free low-smoke flame-retardant polyolefin sheath material on the outside of the fire insulation layer to form a sheath layer 7. The sheath material should have good crusting properties, adhere to the surface of the fire insulation layer after carbonization in a flame environment, and not fall off without external impact.

[0067] In this embodiment, after the sheath layer 7 is burned by fire, the burning material can be sintered into a shell-like shape and attached to the cable surface, which plays a blocking role in the flame spreading into the cable. When the temperature of the ceramic polyolefin material of the fire-insulating layer 6 exceeds 600°C under flame burning, it is sintered into a hard ceramic shell under high temperature and attached to the cable core surface. The residue after burning is an amorphous silicon dioxide material, which can prevent the melting and dripping of the combustible material to expand the flame range, and at the same time prevent the internal decomposition of the combustible products from diffusing outward and the external flame and heat from invading and spreading into the cable. When the ceramic fire-resistant composite tape of the cushion layer 5 is heated under flame burning and the temperature exceeds 500°C, the refractory silicone rubber in the composite tape is sintered into a porcelain-like body and attached to the cable core surface, isolating the flame and heat from spreading and transmitting into the cable. When the ceramic polyolefin material of the insulating layer 3 is sintered into a hard ceramic shell under the action of high temperature and attached to the surface of the conductor when the temperature exceeds 600°C under flame ablation, the residue after combustion is amorphous silicon dioxide material, which has good heat insulation and insulation effects and can prevent flames and heat from being conducted to the conductor. The insulating layer has the dual functions of insulation and fire insulation. The inorganic mineral insulating tape of the refractory layer 2 has excellent electrical insulation properties under high temperature conditions of 1200°C. The composite insulating layer composed of the refractory layer 2 and the insulating layer 3 ensures that the cable can still operate continuously and stably under high temperature environments.

[0068] Through the combined effects of the sheath layer 7, the fireproof layer 6, the cushion layer 5, the insulating layer 3 and the fire-resistant layer 2, this embodiment enables the cable to continue to operate stably for a certain period of time when the temperature of the fire environment continues to rise, thereby ensuring the evacuation of personnel and the implementation of rescue work.

[0069] Embodiment 2:

[0070] like Figure 2 As shown, this embodiment provides a fire-resistant cable suitable for use under temperature-raising conditions of building fires. Unlike Embodiment 1, the cable in this embodiment is a multi-core cable, for example, 5 insulating cores are arranged, and the insulating cores include a conductor 1 and a fire-resistant layer 2 coated on the conductor 1, and an insulating layer 3 extruded on the fire-resistant layer 2. The conductor 1 is formed by twisting a plurality of fine copper wires, the fire-resistant layer 2 is an inorganic mineral insulating tape, which is a mica tape or a ceramic fire-resistant mica tape or a composite structure; the insulating layer 3 is an extruded ceramic polyolefin material; the conductor 1, the fire-resistant layer 2 and the insulating layer 3 together constitute an insulating core, which is twisted into a cable core, and the gaps between the insulating cores of the cable core are filled with inorganic fibers 4, and the cable core is wrapped with a ceramic fire-resistant composite tape to form a cushioning layer 5. The inorganic fiber rope is preferably a high-temperature resistant flame-retardant fiber rope; ceramic polyolefin is extruded outside the cushioning layer to form a fire-proof layer 6; the outermost layer is a sheath layer 7, which is an extruded halogen-free low-smoke flame-retardant polyolefin.

[0071] The difference in manufacturing the cable in this embodiment is that the insulating cores are arranged in the order of yellow, green, red, blue and black in a clockwise direction, and twisted into a cable core on a cabling machine; the gaps between the insulating cores of the cable core are filled with inorganic fibers 4, and the filler should not react with the insulating material. The cable core is wrapped with a wrapping tape to form a cushion layer 5, and the wrapping tape should be a ceramic fire-proof and fire-resistant composite tape; the other steps and contents are the same as those in Example 1.

[0072] Embodiment 3:

[0073] This embodiment provides a method for manufacturing a fire-resistant cable suitable for use under temperature rise conditions of a building fire, which is used to manufacture a fire-resistant cable suitable for use under temperature rise conditions of a building fire as described in Embodiment 1 or Embodiment 2, comprising:

[0074] An inorganic mineral insulating tape is wrapped around the surface of the conductor to form a fire-resistant layer, and a ceramic polyolefin material is extruded on the surface of the fire-resistant layer to form an insulating layer. The insulating cores of the multi-core cable should be twisted into a cable core, and a tape is wrapped around the insulating core of the single-core cable or the cable core of the multi-core cable to form a cushioning layer, and a ceramic polyolefin material is extruded outside the cushioning layer to form a fire-proof layer, and a halogen-free, low-smoke, flame-retardant polyolefin sheath material is extruded outside the fire-proof layer to form a sheathing layer.

[0075] Optionally, preparing a thermoplastic silicone resin, synthesizing a thermoplastic silicone resin;

[0076] The synthesized thermoplastic silicone resin is put into a three-roll mill for grinding to obtain a ceramic rubber compound;

[0077] The ceramicized rubber material is put into a twin-screw extruder for extrusion granulation to obtain a ceramicized polyolefin material;

[0078] The soft copper wires are twisted in a regular arrangement on a frame twisting machine to form a twisted conductor; an inorganic mineral insulating tape is wrapped around the surface of the twisted conductor to form a fire-resistant layer, the inorganic mineral insulating tape should be wrapped in an overlapping manner, the wrapping direction of each layer should be opposite, and the outermost layer is to the right, so as to obtain a fire-resistant conductor; a ceramicized polyolefin material is extruded on the surface of the fire-resistant conductor to form an insulating layer, so as to obtain an insulated wire core; a color ribbon is added to the insulating layer during extrusion, and the colors of the insulated wire core are identified according to yellow, green, red, blue and black color matching;

[0079] Arrange the insulated wire cores in the order of yellow, green, red, blue and black in a clockwise direction and twist them into a cable core on a cabling machine; fill the gaps between the insulated wire cores of the cable core with inorganic fibers; wrap the cable core around and tighten it to form a cushion layer, and the wrapping tape is a ceramic fire-resistant composite tape;

[0080] Extruding ceramic polyolefin material outside the cushion layer to form a fire-insulating layer; the fire-insulating layer should be extruded to form a preset thickness;

[0081] A layer of halogen-free, low-smoke, flame-retardant polyolefin sheath material is extruded outside the fire-insulating layer to form a sheath layer.

[0082] Optionally, the organosilane monomer is reacted at 30-35° C. for 10-11 hours according to an acid-catalyzed alcohol hydrolysis process; the reaction system is heated to 71-75° C., and condensation reaction is carried out under vacuum for 2 hours; the reaction system is heated to 145-150° C., and the reaction is continued for 1.5-2 hours at a pressure of 0.01-0.02 MPa to obtain a colorless viscous liquid, which is cooled to room temperature to obtain a thermoplastic silicone resin.

[0083] Optionally, the synthesized thermoplastic silicone resin is ground in a three-roll mill, and silicon dioxide prepared by vapor deposition is added, mixed and stirred evenly, and then discharged to obtain a ceramic rubber compound.

[0084] Optionally, the prepared ceramic rubber, polyolefin resin, inorganic filler, stabilizer, processing aid and thermal sensitizer are put into a twin-screw extruder for extrusion granulation to prepare a ceramic polyolefin material.

[0085] Optionally, polyolefin resin, ceramic rubber, inorganic filler, accelerator, lubricant, antioxidant, coupling agent, compatibilizer, heat sensitizer, stabilizer, and processing aid are picked up according to a preset ratio, put into a mixer for thorough mixing, and the speed of the mixer is controlled to be 300-350 rpm, and the mixing time is 15-20 minutes;

[0086] Debug the temperature of each zone of the twin-screw extruder granulator. The reference temperature is set as follows: 90-110℃ for barrel zone 1, 150-155℃ for barrel zone 2, 165-170℃ for barrel zone 3, 185-190℃ for barrel zone 4, 180-185℃ for barrel zone 5, 175-180℃ for die head, and 175-180℃ for mold. The twin-screw granulator needs to run at no load for 5-10 minutes based on the reference temperature, then pour the mixed material into the granulator, and the extrudate from the granulator enters the cooling pool for cooling;

[0087] The cooled extrudate is air-cooled to blow away the moisture on the surface, and then enters the pelletizer to be sheared into particles;

[0088] The cooled particles are transported to the dryer for particle drying and water removal. The temperature of the dryer is 65-70°C and the drying time is 1-3 hours.

[0089] The dried particles need to be sealed and stored.

[0090] The above description is only a preferred embodiment of the present embodiment and is not intended to limit the present embodiment. For those skilled in the art, the present embodiment may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present embodiment shall be included in the protection scope of the present embodiment.

Claims

1. A fire-resistant cable suitable for use under building fire temperature rise conditions, characterized in that: It comprises a conductor, and a fire-resistant layer, an insulating layer, a lining layer, a fire-proof layer and a sheath layer which are sequentially arranged outside the conductor; The fire-resistant layer is an inorganic mineral insulating tape, the insulating layer and the fire-proof layer are ceramic polyolefin materials, the cushion layer is a ceramic fire-proof and fire-resistant composite tape, and the sheath layer is a halogen-free, low-smoke, flame-retardant polyolefin sheath material.

2. A fire-resistant cable suitable for use under building fire temperature rise conditions as claimed in claim 1, characterized in that: The ceramic polyolefin material is composed of the following parts by weight: 100-140 parts of polyolefin resin, 100-120 parts of ceramic rubber, 60-80 parts of inorganic filler, 0.5-5 parts of lubricant, 1-5 parts of antioxidant, 0.1-5 parts of coupling agent, 3-10 parts of compatibilizer, 1-20 parts of accelerator, 0.3-3 parts of thermal sensitizer, 0.1-2 parts of stabilizer and 0.5-2.5 parts of processing aid.

3. A fire-resistant cable suitable for use under building fire temperature rise conditions as claimed in claim 2, characterized in that: The ceramic rubber material is a mixture of thermoplastic organic silicon resin and silicon dioxide prepared by vapor deposition method.

4. A fire-resistant cable suitable for use under building fire temperature rise conditions as claimed in claim 1, characterized in that: The conductor is a copper conductor.

5. A method for manufacturing a fire-resistant cable suitable for use under building fire temperature rise conditions, characterized in that: Used to manufacture the fire-resistant cable suitable for use in building fire temperature rise conditions as described in any one of claims 1 to 4, comprising: An inorganic mineral insulating tape is wrapped around the surface of the conductor to form a fire-resistant layer, and a ceramic polyolefin material is extruded on the surface of the fire-resistant layer to form an insulating layer. The insulating cores of the multi-core cable should be twisted into a cable core, and a tape is wrapped around the insulating core of the single-core cable or the cable core of the multi-core cable to form a cushioning layer, and a ceramic polyolefin material is extruded outside the cushioning layer to form a fire-proof layer, and a halogen-free, low-smoke, flame-retardant polyolefin sheath material is extruded outside the fire-proof layer to form a sheathing layer.

6. A method for manufacturing a fire-resistant cable suitable for use under temperature rise conditions of a building fire as described in claim 5, characterized in that: Preparation of thermoplastic silicone resin, synthesis of thermoplastic silicone resin; The synthesized thermoplastic silicone resin is put into a three-roll mill for grinding to obtain a ceramic rubber compound; The ceramicized rubber material is put into a twin-screw extruder for extrusion granulation to obtain a ceramicized polyolefin material; The soft copper wires are twisted in a regular arrangement on a frame twisting machine to form a twisted conductor; an inorganic mineral insulating tape is wrapped around the surface of the twisted conductor to form a fire-resistant layer, the inorganic mineral insulating tape should be wrapped in an overlapping manner, the wrapping direction of each layer should be opposite, and the outermost layer is to the right, so as to obtain a fire-resistant conductor; a ceramicized polyolefin material is extruded on the surface of the fire-resistant conductor to form an insulating layer, so as to obtain an insulated wire core; a color ribbon is added to the insulating layer during extrusion, and the colors of the insulated wire core are identified according to yellow, green, red, blue and black color matching; Arrange the insulated wire cores in the order of yellow, green, red, blue and black in a clockwise direction and twist them into a cable core on a cabling machine; fill the gaps between the insulated wire cores of the cable core with inorganic fibers; wrap the cable core around and tighten it to form a cushion layer, and the wrapping tape is a ceramic fire-resistant composite tape; Extruding ceramic polyolefin material outside the cushion layer to form a fire-insulating layer; the fire-insulating layer should be extruded to form a preset thickness; A layer of halogen-free, low-smoke, flame-retardant polyolefin sheath material is extruded outside the fire-insulating layer to form a sheath layer.

7. A method for manufacturing a fire-resistant cable suitable for use under temperature rise conditions of a building fire as described in claim 6, characterized in that: The organic silane monomer is reacted at 30-35° C. for 10-11 hours according to an acid-catalyzed alcohol hydrolysis process; the reaction system is heated to 71-75° C. and condensed under vacuum for 2 hours; the reaction system is heated to 145-150° C. and reacted at a pressure of 0.01-0.02 MPa for 1.5-2 hours to obtain a colorless viscous liquid, which is cooled to room temperature to obtain a thermoplastic silicone resin.

8. A method for manufacturing a fire-resistant cable suitable for use under temperature-raising conditions of a building fire as described in claim 6, characterized in that: The synthesized thermoplastic silicone resin is put into a three-roll mill for grinding, and silicon dioxide prepared by a vapor deposition method is added, mixed and stirred evenly, and then discharged to obtain a ceramic rubber compound.

9. A method for manufacturing a fire-resistant cable suitable for use under temperature-raising conditions of a building fire as described in claim 6, characterized in that: The prepared ceramic rubber compound, polyolefin resin, inorganic filler, stabilizer, processing aid and heat sensitizer are put into a twin-screw extruder for extrusion granulation to prepare the ceramic polyolefin material.

10. A method for manufacturing a fire-resistant cable suitable for use under building fire temperature rise conditions as claimed in claim 6, characterized in that: Pick up polyolefin resin, ceramic rubber, inorganic filler, accelerator, lubricant, antioxidant, coupling agent, compatibilizer, heat sensitizer, stabilizer and processing aid according to the preset ratio, put them into the mixer for thorough mixing, control the speed of the mixer to 300-350rpm, and mix for 15-20 minutes; Debug the temperature of each zone of the twin-screw extruder granulator. The reference temperature is set as follows: 90-110℃ for barrel zone 1, 150-155℃ for barrel zone 2, 165-170℃ for barrel zone 3, 185-190℃ for barrel zone 4, 180-185℃ for barrel zone 5, 175-180℃ for die head, and 175-180℃ for mold. The twin-screw granulator needs to run at no load for 5-10 minutes based on the reference temperature, then pour the mixed material into the granulator, and the extrudate from the granulator enters the cooling pool for cooling; The cooled extrudate is air-cooled to blow away the moisture on the surface, and then enters the pelletizer to be sheared into particles; The cooled particles are transported to the dryer for particle drying and water removal. The temperature of the dryer is 65-70°C and the drying time is 1-3 hours. The dried particles need to be stored in a sealed container.

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