NL2025371A

NL2025371A - Flexible type mineral insulated fireproof cable

Info

Publication number: NL2025371A
Application number: NL2025371A
Authority: NL
Inventors: Rui Lichun
Original assignee: Jiangsu Pucao Tech Co Ltd
Priority date: 2020-02-20
Filing date: 2020-04-20
Publication date: 2021-09-16
Also published as: CN111415776A; NL2025371B1

Abstract

Disclosed is a flexible type mineral insulated fireproof cable, which belongs to the technical field of cable protection. The flexible type mineral insulated fireproof cable includes four cable cores arranged in an annular array; 3 fireproof mica layer is wrapped outside the cable core; an insulating layer is wrapped outside the fireproof mica layer; an armor layer is sleeved outside the insulating layer; an 1oxygen barrier layer is wrapped outside the four cable cores; and four carbon dioxide filling layers are filled in a cavity between the oxygen barrier layer and the cable core. According to the insulated fireproof cable provided by the present invention, an insulating layer and a fireproof mica layer are wrapped outside a cable core; when the cable is used, a copper core heats, and the fireproof mica layer has good insulation performance and heat resistance; an armor layer is wound on an outer wall of the insulating layer, so that a mechanical strength of the cable can be effectively increased, and an erosion resistance can be improved; and an oxygen barrier layer and an isolation layer that are provided can take effective fireproof and obstruction effect, and effectively control an external fire behavior, thus further protecting the cable.

Description

Flexible type mineral insulated fireproof cable Technical Field The present invention relates to the technical field of cables, and in particular to a flexible type mineral insulated fireproof cable. Background The wire and cable industry is a second industry next to the automobile industry in China, with a satisfaction rate of product variety and an occupancy rate in domestic market being both greater than 90%. As one of the most important research, development and production bases of cable products throughout the world, China has a series of cable products with a unique performance and a special structure, such as a flame-retardant fireproof cable, a high-low temperature resistant cable, a low-inductance low-noise cable, an environment-friendly cable, a low-smoke halogen-free cable, a termite-rat preventing cable, a waterproof and moisture-proof cable, etc., and has formed a certain productivity. Along with continuous improvement of the society on a safety requirement of safety guarantee and system, and with extensive propaganda, promotion and cooperation of a government, an industry and an enterprise, a special cable product with a high performance, a high efficiency and a safety will be widely applied in all walks of life like western developed countries.

At present, a fireproof cable is extensively applied to such important sectors and public places as a high-rise building, a subway, a power station, a nuclear power station, a hospital and an airport. In case of a fire, the fireproof cable can guarantee smooth operation of communication and power circuits, thus winning precious time for rescue of lives and properties, and making an important contribution to decreasing a personal casualty and a property loss.

In recent years, in fire accidents of a power system throughout the world, a proportion of an interruption of power supply for the power system due to ignition of a power cable tends to rise. Therefore, the fireproof cable is used in such places as the power station and a transformer substation, where a great number of electrical devices are provided and a great number of cables are densely paved, to reduce an occurrence rate of the fire accident of the power system, and to guarantee that an important loop is powered without the interruption. The traditional fireproof cable has a limited fireproof ability. When an external environmental temperature is very high, the cable is still ignited; and once the cable is ignited, the traditional fireproof cable cannot limit the combustion within a local range, resulting in that the fire spreads to burn many power devices and lead to a great economic loss. Summary

1. Technical problems to be solved In view of problems in the conventional art, an objective of the present invention is to provide a flexible type mineral insulated fireproof cable. According to the insulated fireproof cable provided by the present invention, an insulating layer and a fireproof mica layer are wrapped outside a cable core; when the cable is used, a copper core heats, and the fireproof mica layer has good insulation performance and heat resistance; an armor layer is wound on an outer wall of the insulating layer, so that a mechanical strength of the cable can be effectively increased, and an erosion resistance can be improved; and an oxygen barrier layer and an isolation layer that are provided can take effective fireproof and obstruction effect, and effectively control an external fire behavior, thus further protecting the cable.

2. Technical solutions In order to solve the above-mentioned technical problems, the present invention uses the following technical solutions.

A flexible type mineral insulated fireproof cable includes four cable cores arranged in an annular array; a fireproof mica layer is wrapped outside the cable core; an insulating layer is wrapped outside the fireproof mica layer; an armor layer is sleeved outside the insulating layer; an oxygen barrier layer is wrapped outside the four cable cores; four carbon dioxide filling layers are filled in a cavity between the oxygen barrier layer and the cable core; the four carbon dioxide filling layers are disposed by tightly attaching to the four cable cores and various bins; an isolating layer is wrapped outside the oxygen barrier layer; a metal protective layer is wrapped outside the isolating layer; a shielding layer is wrapped outside the metal protective layer; and an outer sheath is wrapped outside the shielding layer. An insulating layer and a fireproof mica layer are wrapped outside a cable core; when the cable is used, a copper core heats, and the fireproof mica layer has good insulation performance and heat resistance, so that a safety accident caused by a reduced insulation performance in long-term use of the cable may be prevented; an armor layer is wound on an outer wall of the insulating layer, so that a mechanical strength of the cable can be effectively increased, an erosion resistance can be improved, and a service life of the cable can further be prolonged; and an oxygen barrier layer and an isolation layer that are provided can take effective fireproof and obstruction effect, and effectively control an external fire behavior, thus further protecting the cable.

Further, the insulating layer is a cross-linked polyethylene insulating layer.

Further, the armor layer is a steel tape spirally wound on the outer wall of the insulating layer.

Further, the carbon dioxide filling layer is a low-ignition-point sealing film filled with titanium dioxide inside. The provided carbon dioxide filling layer is fractured in case of a fire, a large amount of released carbon dioxide can put out the fire effectively, and the fire due to internal ignition of the carbon dioxide filling layer is prevented.

Further, the oxygen barrier layer is prepared from a graphene/polyethylene composite material, and a preparation method of the graphene/polyethylene composite material is as follows: graphene and triethoxyoctylsilane having a mass ratio of 1:5-1:4 are dissolved into an organic solvent, and react at a temperature of 30-35°C to generate triethoxyoctylsilane modified graphene oxide, the triethoxyoctylsilane modified graphene oxide is ultrasonically dispersed into an oleate solvent and reacts for 12-24 h at a temperature of 160-170°C to obtain oleate graphene, then the oleate graphene and polyethylene having a mass ratio of 1:100-1:50 are dispersed and dissolved into a certain amount of xylene solvent, and the obtained oleate graphene and polyethylene solution is mixed in a solution blending manner and then precipitated, dried, and pressed by a mold to obtain the graphene/polyethylene composite material. The oxygen barrier layer is prepared from the graphene/polyethylene composite material, so that oxygen, water and the like can be effectively obstructed; and moreover, the oxygen barrier layer can take an effect of a uniform electric field, can effectively prevent a problem of partial discharge or insulation breakdown, inhibits spatial charge accumulation in a cable insulating material and reduces an electrical conductivity.

Further, the isolating layer is prepared from ceramic silicone rubber, and a raw material of the ceramic silicone rubber includes the following components in parts by weight: 80-90 parts of silicone rubber, 3-7 parts of phenolic resin, 10-15 parts of white carbon black, 4-8 parts of calcium metasilicate, 17-26 parts of mica, 2-4 parts of montmorillonite, 3-8 parts of graphene oxide, 1-4 parts of boron oxide, 1-2 parts of vulcanizing agent, 1-2 parts of silane coupling agent, 3-8 parts of ammonium polyphosphate, 2-6 parts of microencapsulated red phosphorus and 1-2 parts of hydroxyl silicone oil. The oxygen barrier layer 7 is prepared from a fireproof material such as silicone rubber and white carbon black, and the oxygen barrier layer is sintered into a hard ceramic armored housing after several minutes of combustion under the burning of a flame. Such a hard ceramic armored housing may effectively obstruct continuous combustion of the flame and prevent seepage of water, and stops smoke completely within short time of burning, so that the cable has a good flame retardance, meets a fireproof requirement in a spraying condition and prolongs a service life.

Further, the silicon rubber is a mixture of methyl vinyl silicone rubber and methyl phenyl vinyl silicone rubber, and a mass ratio of the methyl vinyl silicone rubber to the methyl phenyl vinyl silicone rubber is 30-50:12-32.

Further, the white carbon black is modified white carbon black, and the modified white carbon black is prepared according to a following process: cyanuric chloride and acetonitrile are uniformly mixed, Pentaerythritol Caged Phosphate (PEPA) and triethylamine are added, a temperature is adjusted to 10-15°C under the protection of nitrogen to react for 200-300 min, then eugenol is added to react for 8-10 h at 40-50°C, and a material A is obtained upon aftertreatment; with a silane coupling agent as a modifier, the white carbon black is modified to obtain a material B; and the material A, the material B, styrene and maleic anhydride are added to toluene, then azodiisobutyronitrile is added, a temperature is heated to 75-80°C under the protection of nitrogen to react for 6-9 h, and upon the completion of reaction, filtration, cleaning and drying are performed to obtain the modified white carbon black.

Further, the metal protective layer is a stainless steel tube; and the stainless steel tube is of a corrugated shape. The metal protective layer serves as an auxiliary fireproof layer, and the stainless steel tube is of the corrugated shape and has a high melting point, so that the cable is not combusted and can further be powered continuously at a fire site, and thus the cost is low.

Further, the shielding layer is a metal shielding layer and specifically uses a copper tape shielding layer or a copper wire net shielding layer. The shielding layer formed by the copper tape shielding layer or the copper wire net shielding layer has a good shielding effect, and effectively improves a shielding performance of the fireproof cable.

3. Beneficial effects Compared with the conventional art, the present invention has the following advantages.

(1) According to the insulated fireproof cable provided by the present invention, an insulating layer and a fireproof mica layer are wrapped outside a cable core; when the cable is used, a copper core heats, and the fireproof mica layer has good insulation performance and heat resistance, so that a safety accident caused by a reduced insulation performance in long-term use of the cable may be prevented; an armor layer is wound on an outer wall of the insulating layer, so that a mechanical strength of the cable can be effectively increased, an erosion resistance can be improved, and a service life of the cable can further be prolonged; and an oxygen barrier layer and an isolation layer that are provided can take effective fireproof and obstruction effect, and effectively control an external fire behavior, thus further protecting the cable.

(2) The provided carbon dioxide filling layer is fractured in case of a fire, a large amount of released carbon dioxide can put out the fire effectively, and the fire due to internal ignition of the carbon dioxide filling layer is prevented.

(3) The oxygen barrier layer is prepared from a graphene/polyethylene composite material, so that oxygen, water and the like can be effectively obstructed; and moreover, the oxygen barrier layer can take an effect of a uniform electric field, can effectively prevent a problem of partial discharge or insulation breakdown, inhibits spatial charge accumulation in a cable insulating material and reduces an electrical conductivity.

(4) An isolating layer is provided in the present invention. The oxygen barrier layer is prepared from a fireproof material such as silicone rubber and white carbon black, and the oxygen barrier layer is sintered into a hard ceramic armored housing after several minutes of combustion under the burning of a flame. Such a hard ceramic armored housing may effectively obstruct continuous combustion of the flame and prevent seepage of water, and stops smoke completely within short time of burning, so that the cable has a good flame retardance, meets a fireproof requirement in a spraying condition and prolongs a service life.

(5) A metal protective layer serves as an auxiliary fireproof layer, and a stainless steel tube is of a corrugated shape and has a high melting point, so that the cable is not combusted and can further be powered continuously at a fire site, and thus the cost is low.

(6) A shielding layer formed by a copper tape shielding layer or a copper wire net shielding layer has a good shielding effect, and effectively improves a shielding performance of the fireproof cable.

Brief Description of the Drawings Fig. 1 is a front view of the present invention.

In the figures:

1. cable core, 2. fireproof mica layer, 3. insulating layer, 4. armor layer, 5.

carbon dioxide filling layer, 6. oxygen barrier layer, 7. isolating layer, 8. metal protective layer, 9. shielding layer, and 10. outer sheath. Detailed Description of the Embodiments The technical solutions of the embodiments of the present invention are clearly and completely described below in combination with the accompanying drawings in the embodiments of the present invention. It is apparent that the described embodiments are only a part of embodiments of the present invention, instead of all the embodiments. All of the other embodiments, obtained by those of ordinary skill in the art based on the embodiments of the present invention without any inventive efforts, fall into the protection scope of the present invention.

In the description of the embodiments of the present invention, orientation or position relationships indicated by the terms "upper", "lower", "inner", “outer”, "top/bottom end" etc. are based on the orientation or position relationships as shown in the drawings, for ease of the description of the present invention only, rather than indicating that the indicated device or element have a particular orientation and must be constructed and operated in the particular orientation. Therefore, these terms should not be understood as a limitation to the present invention. In addition, the terms “first” and “second” are used for descriptive purposes only and cannot be construed as indicating or implying a relative importance.

In the description of the present invention, it should be noted that, unless otherwise clearly stated and limited, the terms “mounted”, “provided with”, “sleeve” , and “connected” should be understood broadly, for instance, it can be a fixed connection, a detachable connection or an integral connection; it can be a mechanical connection, and can also be an electrical connection; it can be a direct connection, can also be an indirect connection by an intermediary, and can be an internal communication of two elements. Those of ordinary skill in the art may understand concrete meanings of the terms in the present invention as per specific circumstances.

Embodiment 1 Referring to Fig. 1, a flexible type mineral insulated fireproof cable includes four cable cores 1 arranged in an annular array; a fireproof mica layer 2 is wrapped outside the cable core 1; an insulating layer 3 is wrapped outside the fireproof mica layer 2; an armor layer 4 is sleeved outside the insulating layer; an oxygen barrier layer 6 is wrapped outside the four cable cores 1; four carbon dioxide filling layer 5 is filled in a cavity between the oxygen barrier layer 6 and the cable core 1; the four carbon dioxide filling layers 5 are disposed by tightly attaching to the four cable cores 1 and various bins 6; an isolating layer 7 is wrapped outside the oxygen barrier layer 6; a metal protective layer 8 is wrapped outside the isolating layer 7; a shielding layer 9 is wrapped outside the metal protective layer 8; and an outer sheath 10 is wrapped outside the shielding layer 9.

According to the insulated fireproof cable provided by the present invention, an insulating layer 3 and a fireproof mica layer 2 are wrapped outside a cable core; when the cable is used, a copper core heats, and the fireproof mica layer 3 has good insulation performance and heat resistance, so that a safety accident caused by a reduced insulation performance in long-term use of the cable may be prevented; an armor layer 4 is wound on an outer wall of the insulating layer, so that a mechanical strength of the cable can be effectively increased, an erosion resistance can be improved, and a service life of the cable can further be prolonged; and an oxygen barrier layer 6 and an isolation layer 7 that are provided can take effective fireproof and obstruction effect, and effectively control an external fire behavior, thus further protecting the cable.

The insulating layer 3 is a cross-linked polyethylene insulating layer.

The armor layer 4 is a steel tape spirally wound on the outer wall of the insulating layer 3.

The carbon dioxide filling layer 5 is a low-ignition-point sealing film filled with titanium dioxide inside. The provided carbon dioxide filling layer 5 is fractured in case of a fire, a large amount of released carbon dioxide can put out the fire effectively, and the fire due to internal ignition of the carbon dioxide filling layer is prevented.

The oxygen barrier layer 6 is prepared from a graphene/polyethylene composite material, and a preparation method of the graphene/polyethylene composite material is as follows: graphene and triethoxyoctylsilane having a mass ratio of 1:5-1:4 are dissolved into an organic solvent, and react at a temperature of 30-35°C to generate triethoxyoctylsilane modified graphene oxide, the triethoxyoctylsilane modified graphene oxide is ultrasonically dispersed into an oleate solvent and reacts for 12-24 h at a temperature of 160-170°C to obtain oleate graphene, then the oleate graphene and polyethylene having a mass ratio of 1:100-1:50 are dispersed and dissolved into a certain amount of xylene solvent, and the obtained oleate graphene and polyethylene solution is mixed in a solution blending manner and then precipitated, dried, and pressed by a mold to obtain the graphene/polyethylene composite material.

The oxygen barrier layer 6 is prepared from a graphene/polyethylene composite material, so that oxygen, water and the like can be effectively obstructed; and moreover, the oxygen barrier layer can take an effect of a uniform electric field, can effectively prevent a problem of partial discharge or insulation breakdown, inhibits spatial charge accumulation in a cable insulating material and reduces an electrical conductivity.

The isolating layer 7 is prepared from ceramic silicone rubber, and a raw material of the ceramic silicone rubber includes the following components in parts by weight: 80-90 parts of silicone rubber, 3-7 parts of phenolic resin, 10-15 parts of white carbon black, 4-8 parts of calcium metasilicate, 17-26 parts of mica, 2-4 parts of montmorillonite, 3-8 parts of graphene oxide, 1-4 parts of boron oxide, 1-2 parts of vulcanizing agent, 1-2 parts of silane coupling agent, 3-8 parts of ammonium polyphosphate, 2-6 parts of microencapsulated red phosphorus and 1-2 parts of hydroxyl silicone oil.

An isolating layer 7 is provided in the present invention. The oxygen barrier layer 7 is prepared from a fireproof material such as silicone rubber and white carbon black, and the oxygen barrier layer is sintered into a hard ceramic armored housing after several minutes of combustion under the burning of a flame. Such a hard ceramic armored housing may effectively obstruct continuous combustion of the flame and prevent seepage of water, and stops smoke completely within short time of burning, so that the cable has a good flame retardance, meets a fireproof requirement in a spraying condition and prolongs a service life.

The silicon rubber is a mixture of methyl vinyl silicone rubber and methyl phenyl vinyl silicone rubber, and a mass ratio of the methyl vinyl silicone rubber to the methyl phenyl vinyl silicone rubber is 30-50:12-32.

The white carbon black is modified white carbon black, and the modified white carbon black is prepared according to a following process: cyanuric chloride and acetonitrile are uniformly mixed, PEPA and triethylamine are added, a temperature is adjusted to 10-15°C under the protection of nitrogen to react for 200-300 min, then eugenol is added to react for 8-10 h at 40-50°C, and a material A is obtained upon aftertreatment; with a silane coupling agent as a modifier, the white carbon black is modified to obtain a material B; and the material A, the material B, styrene and maleic anhydride are added to toluene, then azodiisobutyronitrile is added, a temperature is heated to 75-80°C under the protection of nitrogen to react for 6-9 h, and upon the completion of reaction, filtration, cleaning and drying are performed to obtain the modified white carbon black.

The metal protective layer 8 is a stainless steel tube; and the stainless steel tube is of a corrugated shape. The metal protective layer 8 serves as an auxiliary fireproof layer, and the stainless steel tube is of the corrugated shape and has a high melting point, so that the cable is not combusted and can further be powered continuously at a fire site, and thus the cost is low.

The shielding layer 9 is a metal shielding layer and specifically uses a copper tape shielding layer or a copper wire net shielding layer. The shielding layer formed by the copper tape shielding layer or the copper wire net shielding layer has a good shielding effect, and effectively improves a shielding performance of the fireproof cable.

The above are merely preferred and specific implementation manners of the present invention. The protection scope of the present invention is not limited thereto. Any equivalent replacement or change made by those of skill in the art according to the technical solutions and improved concepts of the present invention within a disclosed technical scope of the present invention should be included in the protection scope of the present invention.

Claims

Conclusions

1. A flexible mineral insulated refractory cable, consisting of four cable cores (1) arranged in a circular array, is characterized by: the outside of the cable core (1) is wrapped with a refractory micelle layer (2), the refractory mica insulation layer (3) is wrapped on the outside of the micelle layer (2), an armor layer (4) on the outside of the insulation layer and an oxygen barrier layer (6) on the outside of the four cable cores (1), the cavity of the oxygen barrier layer (6) and the cable core (1) is filled with four carbon dioxide filling layers {5}, the four carbon dioxide filling layers {5} and the four cable cores (1) respectively, it is arranged in close contact with the oxygen barrier layer (6), the outside of the oxygen barrier layer (6) is wrapped with an insulating layer (7) and the outside of the insulating layer (7) is wrapped with a metal protective layer (8), and on the outside of the metal protective layer (8) is a shielding layer (9) wrapped and on the outside of the shielding layer (9) is wrapped in an outer sheath (10).

A flexible mineral insulated refractory cable according to claim 1, characterized by: said insulating layer (3) is a cross-linked insulating polyethylene layer.

A flexible mineral insulated refractory cable according to claim 1, characterized by : the armor layer (4) is a steel strip spirally wound on the outer wall of the insulation layer (3).

A flexible mineral insulated refractory cable according to claim 1, characterized by: the carbon dioxide filling layer (5) is a layer of fire-resistant sealing film filled with titanium dioxide.

5. A flexible mineral insulated refractory cable according to claim 1, characterized by: the oxygen barrier layer (6) is made of a graphene/polyethylene composite material, the method of preparation of a graphene/polyethylene composite material is: graphene and octyltriethyl in a weight ratio of 1 :5-1:4, the oxysilane is dissolved in an organic solvent and reacted at a temperature of 30-35°C to produce octyltriethoxysilane modified graphene oxide, it is ultrasonically dispersed in an oleic acid solvent and reacted at a temperature of 160-170° C for 12-24 hours to obtain oleic graphene, and then disperse and dissolve oleic graphene with polyethylene in a weight ratio of 1:100-1:50 and polyethylene in a certain amount of xylene solvent, and obtain the solution by means of solution mixing, and the oleic graphene is mixed with a polyethylene solution, and then precipitated, dried d and formed into a graphene/polyethylene composite material.

A flexible mineral insulated refractory cable according to claim 1, is characterized by: the aforementioned insulating layer (7) is made of silicon ceramic rubber, and the raw materials of the silicon ceramic rubber contain the following components by weight: silicone rubber 80-90%, phenolic resin 3- 7% and white soot 10-15%, wollastonite 4-8%, mica 17-26%, montmorillonite 2-4%, graphene oxide 3-8%, boron oxide 1-4%, vulcanizing agent 1-2%, silane coupling agent 1- 2%, ammonium polyphosphate 3-8%, microcapsule red phosphorus 2-6% and hydroxy silicone oil 1-2%.

A flexible mineral insulated refractory cable according to claim 7, characterized by: The silicone rubber is a mixture of methylvinyl-silicone rubber and methylphenylvinyl-silicone rubber, and the weight ratio of methylvinyl-silicone rubber to methylphenylvinyl-silicone rubber is 30-50:12-32.

8. A flexible mineral insulated refractory cable according to claim 7, is characterized by: the white carbon black is modified, the modified white carbon black is prepared by the following process: melamine and acetonitrile are mixed uniformly, pentaerythritol cage phosphate PEPA and triethylamine are added and protected of nitrogen, at a temperature of 10-15°C, allowed to react for 200-300 min, then add eugenol and react for 8-10 hours at 40-50°C, after this treatment material A is obtained, the silane coupling agent is used as a modifier for silica, the modification to obtain material B; the material A, material B, styrene and maleic anhydride are added to toluene and then azobisisobutyronitrile was added, and the temperature was raised to 75-80°C under the protection of nitrogen and the reaction was carried out for 6-9 hours, at the end it was modified silica obtained by filtration, washing and drying.

A flexible mineral insulated refractory cable according to claim 1, characterized by: the aforementioned metal protective layer (8) is a stainless steel tube and it is corrugated.

A flexible mineral insulated refractory cable according to claim 1, characterized by : said shielding layer (9) is a metallic shielding layer with copper tape or copper wire mesh.