Super-high-temperature-resistant fluororubber material and maritime work medium-voltage super-fire-resistant cable with same

Abstract

The invention discloses a super-high-temperature-resistant fluororubber material and a maritime work medium-voltage super-fire-resistant cable with the same. The super-high-temperature-resistant fluororubber material comprises 100 parts of fluororubber; 15 parts of carbon black; 3 parts of peroxide vulcanization; 4 parts of assistant crosslinking; 3-5 parts of an acid acceptor; 1-2 parts of an auxiliary acid acceptor; 5 parts of a filler; 2-4 parts of a processing aid; the fluororubber comprises first fluororubber and second fluororubber, both the first fluororubber and the second fluororubber are ternary fluororubber, the fluorine content of the first fluororubber is greater than or equal to 70%, and the fluorine content of the second fluororubber is 60%-65%; the peroxide vulcanizing agent is set to be diphenylethane peroxide; the fluororubber comprises the first fluororubber and the second fluororubber, the fluorine content of the first fluororubber is larger than or equal to 70%, the fluorine content of the second fluororubber is set to be 65%-70%, the two kinds of fluororubber are mixed, the heat resistance can be guaranteed, meanwhile, the mechanical performance is improved, and compared with all fluororubber with the high fluorine content, the cost is more economical.

Description

Technical Field

[0001] The invention relates to material preparation, in particular to an ultra-high temperature resistant fluororubber material and an offshore medium voltage ultra-fire resistant cable having the same. Background Art

[0002] As the design tonnage of ships and offshore platforms continues to increase, their electricity consumption also increases. In order to meet the requirements of high-power power transmission, the voltage level of trunk line cables has also been increased from 1.8 / 3kV and below to 3.6 / 6kV and above. At the same time, in order to meet the fire protection requirements of ships and offshore platforms, fire resistance requirements are put forward for cables with rated voltages of 3.6 / 6kV or above in special areas.

[0003] As the voltage level of fire-resistant cables increases from 1.8 / 3kV and below to 3.6 / 6kV and above, conventional insulation materials can no longer meet the fire resistance requirements under high voltage. Conventional insulation materials are usually polyethylene materials, but the voltage level of medium-voltage cables is above 3.6 / 6kV, and ordinary polyethylene materials cannot withstand high-voltage electric fields. Therefore, an ultra-high-temperature resistant material is needed to meet the fire resistance requirements of medium-voltage cables. Summary of the invention

[0004] The present invention overcomes the shortcomings of the prior art and provides an ultra-high temperature resistant fluororubber material and a marine medium voltage ultra-fire resistant cable having the same.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is: an ultra-high temperature resistant fluororubber material, comprising:

[0006]

[0007]

[0008] The fluororubber includes a first fluororubber and a second fluororubber, the first fluororubber is greater than or equal to 1.5 times the second fluororubber, the first fluororubber and the second fluororubber are both ternary fluororubbers, the fluorine content of the first fluororubber is greater than or equal to 70%, and the fluorine content of the second fluororubber is 60%-65%;

[0009] The peroxide curing agent is configured as diphenyl ethane peroxide.

[0010] More specifically, the fluorine content of the first fluororubber is set to 70%, and the fluorine content of the second fluororubber is set to 65%.

[0011] More specifically, the first fluororubber is set at 80 parts, and the second fluororubber is set at 20 parts.

[0012] More specifically, the first fluororubber is set at 70 parts, and the second fluororubber is set at 30 parts.

[0013] More specifically, the acid absorber is configured as light magnesium oxide.

[0014] More specifically, the filler is configured as silicon dioxide.

[0015] More specifically, the auxiliary acid absorbent is calcium carbonate, and the auxiliary cross-linking agent is allyl isocyanurate.

[0016] More specifically, the processing aids are polyethylene wax and engine oil.

[0017] A medium-voltage super-fire-resistant offshore cable comprises a conductor, on the periphery of which are arranged in sequence a conductor shielding layer, an insulating layer, an insulating shielding layer, a metal shielding layer, a thermal insulation layer, an armoring layer and an outer sheath, wherein the insulating layer is arranged to be the above-mentioned super-high-temperature-resistant fluororubber material.

[0018] More specifically, the thermal insulation layer is configured as ceramic polyolefin.

[0019] More specifically, the conductor, conductor shielding layer, insulating layer, insulating shielding layer and metal shielding layer are sequentially arranged to form a core unit, a number of the core units are twisted into a cable core, and expanded glass fiber rope is filled inside the cable core.

[0020] The present invention solves the defects existing in the background technology and has the following beneficial effects:

[0021] In this solution, the fluororubber includes a first fluororubber and a second fluororubber. The fluorine content of the first fluororubber is greater than or equal to 70%, and the fluorine content of the second fluororubber is set to 65%-70%. The mixture of the two fluororubbers can improve the mechanical properties while ensuring the heat resistance, and is more cost-effective than using only high-fluorine-content fluororubbers. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The present invention is further described below in conjunction with the accompanying drawings and embodiments;

[0023] Figure 1 is a schematic cross-sectional view of the cable of the present invention;

[0024] In the figure: 1. Conductor; 2. Conductor shielding layer; 3. Insulation layer; 4. Insulation shielding layer; 5. Metal shielding layer; 6. Expanded glass fiber rope filling; 7. Non-woven fabric wrapping tape; 8. Insulation layer; 9. Armor layer; 10. Outer sheath. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical scheme and advantages of the implementation of the present invention clearer, the technical scheme in the embodiment of the present invention will be described in more detail below in conjunction with the drawings in the embodiment of the present invention. In the drawings, the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The described embodiments are part of the embodiments of the present invention, not all of the embodiments. The embodiments described below with reference to the drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limitations on the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0026] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the scope of protection of the present invention. The embodiments of the present invention are described in detail below in conjunction with the drawings.

[0027] It should be understood that the drawings are only used to illustrate the present application.

[0028] The present invention will now be further described in detail with reference to the accompanying drawings and embodiments. These drawings are simplified schematic diagrams that only illustrate the basic structure of the present invention in a schematic manner, and therefore only show the components related to the present invention.

[0029] A super high temperature resistant fluororubber material, comprising: 100 parts of fluororubber; 15 parts of carbon black; 3 parts of peroxide vulcanizer; 4 parts of cross-linking agent; 3-5 parts of acid absorber; 1-2 parts of auxiliary acid absorber; 5 parts of filler; 2-4 parts of processing aid; further, the first fluororubber is set at 80 parts, and the second fluororubber is set at 20 parts.

[0030] Another example is that the cable radiates at a corner and needs to be more flexible, so the formula is slightly adjusted:

[0031] A super high temperature resistant fluororubber material, comprising: 100 parts of fluororubber; 10 parts of carbon black; 3 parts of peroxide vulcanizer; 4 parts of cross-linking agent; 3-5 parts of acid absorber; 1-2 parts of auxiliary acid absorber; 3 parts of filler; 4-6 parts of processing aid; 1-2 parts of optional softener; wherein the optional softener is set to cyclohexane oil, the first fluororubber is set to 70 parts, and the second fluororubber is set to 30 parts.

[0032] The fluororubber includes a first fluororubber and a second fluororubber, the proportion of the first fluororubber is greater than or equal to 1.5 times the proportion of the second fluororubber, the fluorine content of the first fluororubber is greater than or equal to 70%, and the fluorine content of the second fluororubber is set to 60%-65%; more specifically, the fluorine content of the first fluororubber is 70%, and the fluorine content of the second fluororubber is 65%. In fluororubber, the higher the fluorine content, the better the heat resistance and chemical stability of the material. The fluorine content of the fluororubber commonly available on the market is 65%-70%, but in order to improve the heat resistance, in this solution, the fluorine content in the first fluororubber is increased to the upper limit of 70%, so that the mechanical properties can be improved while ensuring the heat resistance, and the cost is more economical than using all fluororubbers with high fluorine content.

[0033] Fluororubbers with different fluorine contents can bring different performance advantages, especially in terms of chemical resistance, heat resistance, mechanical strength, etc. There are three types of fluorine rubbers with different fluorine contents on the market, including low fluorine rubber, which contains about 65% fluorine; medium fluorine rubber, which contains about 68%-71% fluorine; and high fluorine rubber, which contains more than 70% fluorine.

[0034] Among them, low fluorine content fluororubber has better mechanical properties, such as tensile strength and tear strength, better compression permanent deformation performance, and relatively low cost. However, its high temperature resistance is slightly poor, the long-term use temperature range is narrow, and its resistance to certain chemical media is relatively weak.

[0035] Medium fluorine content fluororubber has good high temperature resistance and is suitable for use at higher temperatures. Good chemical resistance, especially for oils, fuels and some organic solvents. However, compared with low fluorine content fluororubber, the cost may be slightly higher. The mechanical properties may be slightly inferior to high fluorine content fluororubber.

[0036] High fluorine content fluororubber has excellent high temperature resistance and is suitable for extreme high temperature environments. Better chemical resistance, especially for strong acids, strong bases and some strong oxidants. Highest cost. Mechanical properties (such as tensile strength and tear strength) may not be as good as low fluorine content fluororubber. More difficult to process and requires higher processing temperature.

[0037] Therefore, the formula of this solution uses 80 parts of the first fluororubber with a fluorine content of 70% and 20 parts of the second fluororubber with a fluorine content of 65%. In this solution, the first fluororubber and the second fluororubber are set as ternary fluororubber. The ratio of this solution can improve the mechanical properties while ensuring the heat resistance, and the cost is more economical than using all fluororubbers with high fluorine content.

[0038] When preparing materials, priority is given to ensuring the heat resistance of the materials. Relatively speaking, the higher the fluorine content of fluororubber, the better its heat resistance. Although the performance of fluororubber with a fluorine content of 70% is better, it will be relatively harder and the cost will be relatively higher. A portion of fluororubber with a fluorine content of 65% can also achieve this heat resistance. And the softness of the material after the two fluorine contents of fluororubber are mixed is better than that of the fluororubber with a fluorine content of 70%. The softness is usually measured by the Shore hardness. A material that is too hard cannot bend when it is laid after being cabled, which also affects the use of the cable. At the same time, considering the processing performance of the material, fluororubber with a high fluorine content may be more difficult during processing, such as requiring a higher processing temperature, etc., while fluororubber with a low fluorine content is easier to process. By mixing and using, the processing performance of the overall material can be improved.

[0039] Comparison between the two types of fluororubber mixed in this solution and other materials on the market:

[0040]

[0041] From the table above, we can see that while ensuring good tensile strength, we also need to ensure temperature resistance. Since the economic cost of using 70% fluorine rubber is high and the hardness is high, and the temperature resistance of using 65% fluorine rubber is not enough, we use a mixture of the two to ensure high temperature resistance. At the same time, if the Shore hardness is higher, the cable cannot be bent during laying after being made, which affects the use of the cable.

[0042] The vulcanization system of the present solution uses a more efficient combination of vulcanizer and accelerator, and adopts a peroxide vulcanization system, because peroxide vulcanization can provide better high-temperature stability. More specifically, the peroxide vulcanizing agent is set to be diphenyl ethane peroxide.

[0043] The acid absorber is set to be light magnesium oxide. Increasing the amount of the acid absorber can improve the quality of vulcanization and further improve the heat resistance. Therefore, the light magnesium oxide is set to 3-5 parts, and the optimal weight is set to 5 parts.

[0044] The filler is silicon dioxide, and high-purity and high-dispersibility silicon dioxide can improve the heat resistance of the vulcanized rubber.

[0045] The auxiliary cross-linking agent is allyl isocyanurate. The auxiliary acid absorbent is calcium carbonate. The processing aid is polyethylene wax and engine oil, the polyethylene wax is 1-2 parts, the engine oil is 1-2 parts, and the engine oil is cycloparaffin oil.

[0046] The specific production process of an ultra-high temperature resistant fluororubber material is as follows:

[0047] First, the first fluororubber and the second fluororubber are preliminarily mixed in an internal mixer, and then carbon black, diphenyl ethane peroxide, allyl isocyanurate, light magnesium oxide, calcium carbonate, polyethylene wax and engine oil are added and mixed thoroughly until all the ingredients are evenly dispersed.

[0048] Subsequently, the mixed rubber is transferred to the open mill for thin pass to further improve the mixing uniformity and remove air. After the thin pass, the rubber is placed for 24 hours to allow the various components to interact better.

[0049] Next, use an extruder to extrude the parked rubber into the desired shape, and control the extrusion temperature at 100-140°C. Finally, put the extruded semi-finished product into a vulcanizing furnace for vulcanization treatment. The vulcanization temperature is set at 170-200°C. The vulcanization time depends on the thickness and shape of the product, generally 30 minutes to several hours. After vulcanization, the product is cooled, cleaned, inspected, etc. to complete the insulation production process.

[0050] A medium voltage super fire-resistant cable for offshore engineering, such as Figure 1 As shown, it includes a conductor 1, a conductor shielding layer 2 is extruded on the periphery of the conductor 1, an insulating layer 3 is extruded on the periphery of the conductor shielding layer 2, and an insulating shielding layer 4 is extruded on the periphery of the insulating layer 3 to form an insulating core; a metal shielding layer 5 is woven on the periphery of the insulating core to form a core unit, a plurality of the core units are twisted into a cable core, a non-woven fabric tape 7 is wrapped around the core units while the core units are twisted, an expanded glass fiber rope filling 6 is arranged in the gap of the cable core, a heat insulation layer 8 is extruded on the periphery of the cable core, an armor layer 9 is woven on the periphery of the heat insulation layer 8, and an outer sheath 10 is cross-linked on the periphery of the armor layer 9.

[0051] The conductor 1 adopts the fifth type of tinned conductor specified in the IEC 60228 standard, which is formed by twisting a plurality of tinned monofilaments. The diameter of each tinned monofilament is the same. The diameter of the galvanized monofilament is set according to needs, but the diameter of the tinned monofilament is not less than 0.4mm. The fifth type of tinned conductor has good flexibility. The finished cable produced by it is easy to bend, which can reduce the difficulty of cable installation and laying and reduce the possibility of cable breakage.

[0052] The outer periphery of the conductor 1 uses a 150+100+60 three-layer co-extrusion continuous vulcanization production line to simultaneously extrude a conductor shielding layer 2, an insulating layer 3 and an insulating shielding layer 4 to form an insulated wire core. The conductor shielding layer 2 is set as a semi-conductive conductor shielding layer, the insulating shielding layer 4 is set as a semi-conductive insulating shielding layer, and the material of the insulating layer 3 is super high temperature resistant fluororubber, and the super high temperature resistant fluororubber material has super heat-resistant insulation performance below 260°C.

[0053] The metal shielding layer 5 is configured to be woven from tinned copper wires, and the metal shielding layer 5 is woven around the outer periphery of the insulating core to form a cable core. A plurality of tinned copper wires are provided, and the diameters of the plurality of tinned copper wires are the same. The diameter of each of the tinned copper wires is configured to be 0.2 mm, and the braiding density of the plurality of tinned copper wires is greater than or equal to 80%.

[0054] The cable core is configured to be formed by twisting a number of insulating cores. Specifically, the cable core is configured to be formed by twisting three insulating cores. During the twisting process of the three insulating cable cores, a layer of non-woven fabric tape 7 is wrapped around the outer periphery of the three insulating cable cores. The thickness of the non-woven fabric is set to 0.2 mm, and the overlap rate is set to 15%-20%. A gap will be formed in the middle of the twisted cable core. If the gap is retained, it will affect the strength and fire resistance of the cable. At the same time, it is easy to be squeezed and deformed, and the electric field will be uniformly broken down. Therefore, an expanded glass fiber rope is set to fill the gap 6. Of course, ordinary glass fiber ropes can also be filled in the gaps, but the glass fiber may cause prickly hands during use. Therefore, in this scheme, the glass fiber rope is an expanded glass fiber rope that has been subjected to expansion treatment. The preparation of the expanded glass fiber rope mainly includes fiber molding, fiber stranding and expansion treatment.

[0055] The heat insulation layer 8 is configured to be a low-smoke, halogen-free ceramic polyolefin material, and the low-smoke, halogen-free ceramic polyolefin material is produced by extrusion using an extruder.

[0056] The armor layer 9 is configured as a tinned copper wire braided armor layer, a plurality of tinned copper wires are configured, the diameters of the plurality of tinned copper wires are the same, the diameter of each tinned copper wire is configured to be 0.4 mm, and the braiding density is greater than or equal to 80%.

[0057] The outer sheath 10 is configured as a radiation cross-linked low-smoke halogen-free sheath, and the material of the radiation cross-linked low-smoke halogen-free sheath is extruded using an extruder.

[0058] Due to the large outer diameter of the medium voltage cable, electrons are emitted vertically from the top of the cable, and the molecular chains of the sheath are cross-linked under the action of the electrons. This causes the sheath above the cable to be acted upon by electrons higher than the sheath below the cable, resulting in uneven irradiation. To ensure uniform irradiation of the cable, a reflective magnet is installed under the cable. A strong magnetic field is used to change the direction of electron movement so that the outer sheath 10 of the cable is evenly acted upon by electrons, thereby ensuring the performance consistency of the outer sheath 10 of the cable.

[0059] The preparation process of a medium voltage super fire-resistant cable for offshore engineering is as follows:

[0060] A plurality of tinned monofilament bundles are twisted into a conductor 1, and then the conductor shielding layer 2, the insulating layer 3 and the insulating shielding layer 4 are sequentially extruded from close to the conductor 1 to far away from the conductor 1 through a production line. The conductor shielding layer 2 and the insulating shielding layer 4 are both configured as semi-conductive shielding materials, and the insulating layer 3 is configured as an ultra-high temperature resistant fluororubber material to ensure the fire resistance of the cable. The conductor 1, the conductor 1 shielding layer, the insulating layer 3 and the insulating shielding layer 4 are closely fitted to each other to form an insulated wire core.

[0061] A metal shielding layer 5 is woven around the outer periphery of the insulating core to form a core unit, and the metal shielding layer 5 is set to be woven with tinned copper wire. Then three core units with the same structural performance are twisted to form a cable core. During the twisting process of the three core units, a layer of non-woven fabric is wrapped around the outer periphery. After the non-woven fabric is wrapped, a gap is formed inside the cable core. In order to reduce the extrusion deformation of the cable, the gap is filled with expanded glass fiber rope.

[0062] After the expansion fiberglass rope is filled, an insulation layer 8 is extruded on the periphery of the cable core. The insulation layer 8 is set as a low-smoke halogen-free ceramic polyolefin material. After the insulation layer 8 is extruded, an armor layer 9 is set on the periphery of the insulation layer 8. The armor layer 9 is also set as tinned copper wire braiding, but the diameter of the tinned copper wire of the armor layer 9 is larger than the diameter of the tinned copper wire of the metal shielding layer 5. After the armor layer 9 is set, an outer sheath 10 is extruded on the periphery of the armor layer 9. The outer sheath 10 adopts a radiation cross-linked low-smoke halogen-free outer sheath 10, and a reflective magnet is added during the radiation cross-linking process to ensure the consistency of the performance of the outer sheath 10.

[0063] When the cable is connected to a voltage of 6kV, the entire cable can burn at a flame of 830°C for 120 minutes without short circuit or disconnection, and can operate normally.

[0064] The ceramicized polyolefin will crust into porcelain in 3-5 minutes under a flame of 830°C, forming a dense heat-resistant oxygen-insulating layer, which makes it difficult for external heat to be transmitted to the inside of the cable. At the same time, the internal insulation layer and filling layer wrapping materials ensure the high temperature resistance requirements, and the high dielectric constant and high heat resistance of the internal fluororubber material can achieve normal operation under high temperature and high voltage conditions, ensuring that the entire cable can be burned in a high-temperature flame of 830°C for 120 minutes and work normally without short circuit or disconnection.

[0065] The present invention solves the defects existing in the background technology and has the following beneficial effects:

[0066] In this scheme, the fluororubber includes a first fluororubber and a second fluororubber, the fluorine content of the first fluororubber is greater than or equal to 70%, and the fluorine content of the second fluororubber is set to 65%-70%. The mixture of the two fluororubbers can improve the mechanical properties while ensuring the heat resistance, and the cost is more economical than using all fluororubbers with high fluorine content; the insulation layer 3 of the cable involved adopts ultra-high temperature resistant fluororubber, and the ultra-high temperature resistant fluororubber has excellent insulation and heat resistance; the filling material adopts expanded glass fiber rope to tightly fill the cable core, avoiding the decomposition of conventional filling materials at high temperature to produce gaps, the deformation of the insulation due to the extrusion force, and the occurrence of uniform electric field breakdown. At the same time, the glass fiber rope is expanded to soften the glass fiber texture, avoiding the problem of glass fiber pricking during use; the insulation layer 8 material adopts ceramic polyolefin, which can form a tight insulation layer 8 above 500°C, effectively isolating the heat outside the cable core, ensuring the integrity of the insulation, so as to meet the normal power transmission in the event of a fire.

[0067] The above is based on the ideal embodiment of the present invention. Through the above description, relevant personnel can make various changes and modifications without departing from the technical concept of the present invention. The technical scope of the present invention is not limited to the content in the specification, and the technical scope must be determined according to the scope of the claims.

[0068] The preferred embodiments of the present invention are described in detail above in conjunction with the accompanying drawings. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, a variety of simple modifications can be made to the technical solution of the present invention, and these simple modifications all belong to the protection scope of the present invention.

[0069] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0070] In addition, various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims

1. An ultra-high temperature resistant fluororubber material, characterized in that: Included are: The fluororubber includes a first fluororubber and a second fluororubber, the first fluororubber is greater than or equal to 1.5 times the second fluororubber, the first fluororubber and the second fluororubber are both ternary fluororubbers, the fluorine content of the first fluororubber is greater than or equal to 70%, and the fluorine content of the second fluororubber is 60%-65%; The peroxide curing agent is configured as diphenyl ethane peroxide.

2. The ultra-high temperature resistant fluororubber material according to claim 1, characterized in that: The fluorine content of the first fluororubber is set to 70%, and the fluorine content of the second fluororubber is set to 65%.

3. The ultra-high temperature resistant fluororubber material according to claim 1, characterized in that: The first fluororubber is provided in an amount of 80 parts, and the second fluororubber is provided in an amount of 20 parts.

4. The ultra-high temperature resistant fluororubber material according to claim 1, characterized in that: The first fluororubber is provided in an amount of 70 parts, and the second fluororubber is provided in an amount of 30 parts.

5. The ultra-high temperature resistant fluororubber material according to claim 1, characterized in that: The acid absorber is configured as light magnesium oxide, and the filler is configured as silicon dioxide.

6. The ultra-high temperature resistant fluororubber material according to claim 1, characterized in that: The auxiliary acid absorber is calcium carbonate, and the auxiliary cross-linking agent is allyl isocyanurate.

7. The ultra-high temperature resistant fluororubber material according to claim 1, characterized in that: The processing aids are polyethylene wax and engine oil.

8. A medium voltage super fire-resistant cable for offshore engineering, characterized in that: The invention comprises a conductor (1), on the periphery of which a conductor shielding layer (2), an insulating layer (3), an insulating shielding layer (4), a metal shielding layer (5), a heat insulating layer (8), an armor layer (9) and an outer sheath (10) are sequentially arranged, wherein the insulating layer (3) is arranged to be the ultra-high temperature resistant fluororubber material as claimed in any one of claims 1 to 7.

9. The medium voltage super fire-resistant cable for offshore engineering according to claim 1, characterized in that: The heat insulation layer (8) is configured as ceramicized polyolefin.

10. The medium voltage super fire-resistant cable for offshore use according to claim 1, characterized in that: The conductor (1), the conductor shielding layer (2), the insulating layer (3), the insulating shielding layer (4) and the metal shielding layer (5) are sequentially arranged to form a wire core unit, and a plurality of the wire core units are twisted into a cable core, and an expanded glass fiber rope is filled inside the cable core.

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