Strong acid-resistant and high-temperature-resistant silicone rubber cable and processing technology thereof

Abstract

This invention relates to the field of cable technology, and in particular to a strong acid and high temperature resistant silicone rubber cable and its processing technology. From the inside out, the cable comprises a multi-core insulated conductor, a filler layer, a cable core wrapping tape, a shielding layer, an optical fiber unit, a buffer layer, a fluorocarbon protective layer, and a corrosion-resistant and high-temperature resistant sheath layer. This invention utilizes a multi-layered protective design, consisting of a conductor anti-corrosion primer, a fluorosilicone resin protective layer for the insulation layer, a synergistic protection of the filler layer, wrapping tape, and buffer layer with ceramicized silicone rubber, a hydrophobic and anti-permeability interlayer, and an acid-resistant filler in the sheath layer. This forms a dense acid-resistant protective system. After immersion in a 50% sulfuric acid / hydrochloric acid environment at 250°C for 720 hours, the sheath layer and wrapping tape show no cracking, swelling, or peeling, and the insulation performance shows no significant decrease. This solves the problem of easy aging and damage of existing cables under strong acid conditions, and the conductor achieves double corrosion protection, completely avoiding strong acid corrosion.

Description

Technical Field

[0001] This invention relates to the field of cable technology, and in particular to a strong acid-resistant and high-temperature-resistant silicone rubber cable and its processing technology. Background Technology

[0002] Silicone rubber cables are widely used in complex industrial environments due to their excellent temperature resistance, electrical insulation, and flexibility. Conventional silicone rubber cables can operate continuously from -60℃ to +200℃, and special formulations can withstand temperatures above 300℃. However, in scenarios such as chemical production, strong acid waste treatment, and high-temperature smelting, cables must withstand the dual effects of strong acid corrosion such as sulfuric acid, hydrochloric acid, and nitric acid, as well as temperatures above 250℃. Existing silicone rubber cables have many performance defects: active groups such as hydroxyl groups in silicone rubber molecules are easily hydrolyzed under strong acids, leading to molecular chain breakage, cracking and swelling of the sheath and insulation layer; long-term use above 250℃ will cause thermal oxidative degradation, making the material hard, brittle, and even carbonized; unreasonable internal structural design results in slow heat dissipation, easy penetration by strong acids, and easy corrosion of the conductor; the gaps in multi-core cables are not densely filled, and the core wires are prone to displacement and wear; existing improvement solutions are mostly single performance optimizations, which are difficult to take into account the combined environment of strong acids and high temperatures, and some solutions have complex manufacturing processes and excessive costs, making them unsuitable for industrial application.

[0003] Currently, in related technologies, fluorosilicone rubber composite sheaths only improve corrosion resistance, and adding high-temperature resistant fillers only optimizes temperature resistance. Neither can simultaneously meet the synergistic requirements of strong acids and high temperatures. Furthermore, they lack dual corrosion protection for the conductor and a hydrophobic, anti-permeability reinforcement design for the cable's outer layer. Additionally, the adaptability of the optoelectronic integration design is insufficient, failing to meet the needs of modern industrial intelligent monitoring. Therefore, developing a multi-core silicone rubber cable that combines excellent resistance to strong acids, high temperatures, mechanical properties, and electrical properties, while achieving optoelectronic integration, structural stability, and a simple manufacturing process, has become a pressing technical challenge in this field. Summary of the Invention

[0004] The technical problem to be solved by this invention is the performance degradation of existing cables under strong acid and high temperature combined environment.

[0005] The technical solution adopted by this invention to solve its technical problem is: a strong acid and high temperature resistant silicone rubber cable, which, from the inside out, includes a multi-core insulated wire core, a filling layer, a cable core wrapping tape, a shielding layer, an optical fiber unit, a buffer layer, a fluorocarbon protective layer, and a corrosion-resistant and high temperature resistant sheath layer. The conductor of the multi-core insulated wire core is provided with a conductor anti-corrosion base coating, and a hydrophobic anti-permeability interlayer is provided between the fluorocarbon protective layer and the corrosion-resistant and high temperature resistant sheath layer. The insulation layer of the insulated wire core and the corrosion-resistant and high temperature resistant sheath layer are both made of modified silicone rubber material, and the filling layer, the cable core wrapping tape, and the buffer layer are all made of the same material as ceramicized silicone rubber.

[0006] The multi-core insulated wire has two or more cores. Each insulated wire core includes a conductor, a conductor anti-corrosion base coating, and an insulation layer. The conductor is made of tin-plated oxygen-free copper wire stranded together. The tin plating layer is 0.05-0.1 mm thick, the oxygen-free copper wire has a purity of ≥99.99%, and the stranding pitch is 10-15 times the conductor diameter. The conductor anti-corrosion base coating is an organosilane anti-corrosion coating with a thickness of 0.01-0.03 mm, which is prepared by compounding γ-aminopropyltriethoxysilane with nano-titanium dioxide.

[0007] The insulating layer is prepared using high-temperature and strong acid resistant modified silicone rubber, with the following formula by weight: 100 parts methyl vinyl silicone rubber, 15-20 parts fluorosilicone resin, 20-30 parts modified nano silicon carbide, 15-25 parts fumed silica, 40-50 parts acid-resistant filler, 10-15 parts high-temperature resistant filler, 2-4 parts crosslinking agent, 1-2 parts antioxidant, and 1-3 parts silane coupling agent; the methyl vinyl silicone rubber has a vinyl content of 0.5-1.0% and a viscosity of 10000-20000 mPa·s, and the modified nano silicon carbide is modified with 3-aminopropyltriethoxysilane and aminosulfonic acid, with a particle size of 0.05-0.1 μm.

[0008] The filling layer is filled with a combination of ceramicized silicone rubber filler rope and high-temperature and acid-resistant sealant. The ceramicized silicone rubber filler rope has a diameter of 0.5-1.2 mm, a tensile strength ≥3.5 MPa, and an elongation at break ≥200%, and contains ceramicized filler and fluorosilicone modified components. The high-temperature and acid-resistant sealant is prepared by mixing silicone resin and nano-silica at a mass ratio of 8:2. The cable core wrapping tape is a ceramicized silicone rubber tape with a wrapping overlap rate ≥50% and a thickness of 0.2-0.3 mm after wrapping.

[0009] The shielding layer is made of silver-plated copper wire with a braiding density of ≥90%, a silver plating thickness of 0.03-0.05mm, and a copper wire diameter of 0.1-0.15mm. The optical fiber unit is located between the shielding layer and the buffer layer. It is a high-temperature and strong acid resistant single-mode or multi-mode optical fiber. The optical fiber is covered with a coating layer and an acid-resistant buffer sleeve in sequence. The sleeve is filled with a high-temperature and acid-resistant sealant. The optical fiber unit is fixed to the shielding layer by ceramicized silicone rubber tape at a spacing of 5-10cm.

[0010] The buffer layer is made of ceramicized silicone rubber tape wrapped around the surface, with an overlap rate of ≥50% and a thickness of 0.3-0.5mm after wrapping. It has a long-term temperature resistance of ≥300℃ and a short-term temperature resistance of ≥350℃, and can resist corrosion from 50% concentration strong acid. The fluorocarbon protective layer is a dense coating prepared by spraying polytetrafluoroethylene emulsion, with a thickness of 0.05-0.1mm, and is dried at 120-140℃ for 10-15 minutes.

[0011] The hydrophobic and impermeable interlayer is a composite layer of fluorocarbon micro-nano coating and aramid nonwoven fabric with a thickness of 0.08-0.12 mm. The aramid nonwoven fabric is impregnated with fluorosilicone resin and has a porosity of ≤5%. The corrosion-resistant and high-temperature resistant sheath layer is made of reinforced modified silicone rubber, and the formula by weight is: 100 parts of fluorosilicone rubber, 30-40 parts of methyl vinyl silicone rubber, 15-25 parts of modified hexagonal boron nitride, 10-15 parts of nano tin oxide, 5-10 parts of expandable graphite, 50-60 parts of acid-resistant filler, 3-5 parts of crosslinking agent, 2-3 parts of anti-aging agent, and 1-2 parts of lubricant.

[0012] The modified hexagonal boron nitride is modified with dodecyltrimethoxysilane and has a particle size of 0.1-0.2 μm; the acid-resistant filler is a mixture of modified nano-calcium carbonate and cerium carbonate in a mass ratio of 2:1, which is modified by soaking in nitric acid aqueous solution and has a particle size of 0.05-0.1 μm; the sheath layer has a thickness of 1.5-2.0 mm and is prepared by vulcanization at 170-190℃ and 0.4-0.6 MPa for 20-25 min.

[0013] A processing method for the aforementioned acid-resistant and high-temperature-resistant silicone rubber cable includes the following steps:

[0014] S1. Conductor preparation: oxygen-free copper wire is drawn, inspected, stranded, tin-plated, and sprayed with a conductor anti-corrosion base coating. After drying, the finished conductor is obtained.

[0015] S2. Insulation layer extrusion: Prepare the insulation layer rubber material according to the formula, extrude it onto the outside of the finished conductor after vacuum kneading, vulcanize and cool to obtain the insulated wire core, and use it after passing the inspection.

[0016] S3. Cable forming process: Twist 2 or more insulated wire cores into a cable with a twisting pitch of 12-18 times the outer diameter of the cable. Fill the gaps between the core wires with ceramicized silicone rubber filler rope and inject high temperature and acid resistant sealant. Wrap the cable core with cable wrapping tape to obtain the cable core.

[0017] S4. Shielding and fiber optic laying: A silver-plated copper wire shielding layer is woven on the outside of the cable core, fiber optic units are laid and fixed with ceramicized silicone rubber tape, and a buffer layer is wrapped around them.

[0018] S5. Preparation of protective layer: Spray fluorocarbon protective layer on the outside of buffer layer and dry it, composite hydrophobic and impermeable interlayer, extrude corrosion-resistant and high-temperature resistant sheath material and vulcanize and cool it.

[0019] S6. Finished product processing: The cable is sealed at the ends and its performance is tested. After passing the test, it is put into storage.

[0020] The preparation conditions for the insulating layer adhesive in step S2 are as follows: mixing at 70-90℃ and vacuum degree of 0.08-0.10MPa for 30-60min, adding crosslinking agent, antioxidant, and silane coupling agent, and continuing mixing for 20-30min; extrusion temperature of 120-140℃, and vulcanization conditions of 160-180℃ and 0.3-0.5MPa for 15-20min; in step S5, the extrusion temperature of the sheath layer adhesive is 130-150℃, and the cable end is sealed with a fluorosilicone rubber sealing sleeve. The sealing sleeve is bonded to the sheath layer and conductor with a high-temperature and acid-resistant adhesive.

[0021] The beneficial effects of this invention are:

[0022] (1) This invention forms a dense acid-resistant protection system through a multi-layer protection design consisting of a conductor anti-corrosion base coating, an insulation layer fluorosilicone resin protective layer, a filler layer-wrapping tape-buffer layer ceramicized silicone rubber synergistic protection, a hydrophobic anti-permeability interlayer, and an acid-resistant filler in the sheath layer. The cable is immersed in a 50% concentration sulfuric acid / hydrochloric acid environment at 250°C for 720 hours, and the sheath layer and wrapping tape do not crack, swell, or fall off, and the insulation performance does not decrease significantly. This solves the problem of easy aging and damage of existing cables under strong acid, and the conductor achieves double corrosion protection, completely avoiding strong acid corrosion.

[0023] (2) By adding high-temperature resistant fillers and antioxidants / anti-aging agents to the insulation layer and sheath layer, the ceramicized silicone rubber filler layer, wrapping tape and buffer layer are sintered into a dense ceramic layer at high temperature to achieve multi-layer heat insulation. The cable can operate stably for a long time from -60℃ to 300℃, withstand 350℃ high temperature for a short time, and does not carbonize or crack at high temperature. The mechanical strength and insulation performance remain stable, meeting the needs of extreme high temperature scenarios such as high temperature smelting and petrochemical.

[0024] (3) The stranding pitch of the multi-core insulated wire is optimized, the filling layer is dense and without gaps, the wrapping tape and buffer layer made of the same ceramic silicone rubber material achieve structural fixation, the newly added hydrophobic and anti-permeability interlayer improves the tensile strength, the cable tensile strength is ≥14MPa, the elongation at break is ≥300%, the core wires do not shift or wear after 100 bends, and it can adapt to complex installation and use environments.

[0025] (4) The optimized modified silicone rubber formula ensures the cable’s excellent electrical insulation performance and can transmit electrical energy stably; the silver-plated copper wire shielding layer effectively shields electromagnetic interference, and the optical fiber unit realizes optoelectronic integrated transmission, which is suitable for intelligent monitoring and data transmission needs in extreme environments such as chemical and metallurgical industries, and expands the application scenarios of the cable.

[0026] (5) The conventional cable extrusion, vulcanization, stranding, wrapping and filling processes are adopted, without the need for new complex production equipment. The preparation process of the new conductor anti-corrosion base coating and hydrophobic anti-permeability interlayer is simple and seamlessly connected with the existing process. All raw materials are conventional chemical raw materials, which are easy to obtain and have reasonable costs. Industrial large-scale production can be realized, and it has a wide range of market application prospects.

[0027] (6) Through the four-fold anti-permeability design of dense filling with sealant, bonding with ceramicized silicone rubber layer, hydrophobic fluorocarbon protective layer, and micro-nano protection of hydrophobic anti-permeability interlayer, strong acid media and water vapor are completely prevented from penetrating into the cable, thus avoiding internal structural corrosion and performance degradation from the source and greatly improving the service life of the cable. Attached Figure Description

[0028] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0029] Figure 1 This is a schematic diagram of the cross-sectional structure of Embodiment 1 of the present invention.

[0030] Figure 2 This is a schematic diagram of the cross-sectional structure of Embodiment 2 of the present invention.

[0031] Figure 3 This is a process flow diagram of the manufacturing process of the acid-resistant and high-temperature-resistant silicone rubber cable of the present invention.

[0032] In the figure: 1. Conductor, 2. Conductor anti-corrosion primer, 3. Insulation layer, 4. Filler layer, 5. Cable core wrapping tape, 6. Shielding layer, 7. Fiber optic unit, 8. Buffer layer, 9. Fluorocarbon protective layer, 10. Hydrophobic and impermeable interlayer, 11. Corrosion-resistant and high-temperature resistant sheath layer. Detailed Implementation

[0033] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, illustrating only the basic structure of the invention, and therefore only show the components relevant to the invention.

[0034] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0035] Example 1, such as Figure 1 and Figure 3The cable shown is a type of strong acid and high temperature resistant silicone rubber cable, which consists of, from the inside out, two insulated wire cores, a filling layer 4, a cable core wrapping tape 5, a shielding layer 6, a single-mode optical fiber unit 7, a buffer layer 8, a fluorocarbon protective layer 9, a hydrophobic and impermeable interlayer 10, and a corrosion-resistant and high temperature resistant sheath layer 11.

[0036] Insulated core: Conductor 1 is made of tin-plated oxygen-free copper wire stranded together, with a tin plating thickness of 0.08mm, oxygen-free copper wire purity of 99.99%, and stranding pitch of 12 times the diameter of conductor 1, which has a diameter of 2.5mm; Conductor anti-corrosion base coating 2 is a composite coating of γ-aminopropyltriethoxysilane and nano-titanium dioxide, with a thickness of 0.02mm; Insulation layer 3 has a thickness of 1.0mm, and its formula by weight is 100 parts methyl vinyl silicone rubber, 18 parts fluorosilicone resin, 25 parts modified nano-silicon carbide, 20 parts fumed silica, 45 parts acid-resistant filler, 12 parts high-temperature resistant filler, 3 parts crosslinking agent, 1.5 parts antioxidant, and 2 parts silane coupling agent; The two insulated cores are stranded into a cable with a stranding pitch of 15 times the outer diameter of the cable.

[0037] Filler layer 4: 0.7mm diameter ceramicized silicone rubber filler rope + silicone resin / nano silica 8:2 sealant for synergistic filling; Cable core wrapping tape 5: ceramicized silicone rubber tape, wrapping overlap rate 55%, thickness after wrapping 0.25mm.

[0038] Shielding layer 6: Braided from silver-plated copper wire with a braiding density of 92%, a silver plating thickness of 0.04 mm, and a copper wire diameter of 0.12 mm; Fiber unit 7: Single-mode fiber (9 μm / 125 μm), with an external coating thickness of 0.15 mm (65% fluorosilicone resin + 35% polyimide), and an acid-resistant buffer sleeve thickness of 0.25 mm. Fiber unit 7 and shielding layer 6 are fixed together by ceramicized silicone rubber tape wound at 8 cm intervals.

[0039] Buffer layer 8: made of ceramicized silicone rubber tape with a wrapping overlap rate of 55% and a thickness of 0.4 mm after wrapping; Fluorocarbon protective layer 9: a dense coating formed by spraying polytetrafluoroethylene emulsion with a thickness of 0.08 mm, dried at 130℃ for 12 min.

[0040] Hydrophobic and impermeable interlayer 10: Fluorocarbon micro-nano coating + aramid nonwoven fabric composite layer, thickness 0.1mm, aramid nonwoven fabric is impregnated with fluorosilicone resin; Corrosion-resistant and high-temperature resistant sheath layer 11: thickness 1.8mm, the formula by weight is 100 parts fluorosilicone rubber, 35 parts methyl vinyl silicone rubber, 20 parts modified hexagonal boron nitride, 12 parts nano tin oxide, 8 parts expandable graphite, 55 parts acid-resistant filler, 4 parts crosslinking agent, 2.5 parts anti-aging agent, and 1.5 parts lubricant.

[0041] The processing technology is carried out according to the above steps S1-S6, wherein the mixing temperature of the insulating layer 3 rubber compound is 80℃, the vacuum degree is 0.09MPa, and the vulcanization temperature is 170℃; the mixing temperature of the corrosion-resistant and high-temperature resistant sheath layer 11 rubber compound is 90℃, and the vulcanization temperature is 180℃.

[0042] Example 2, as Figure 2 and Figure 3 The cable shown is a type of strong acid and high temperature resistant silicone rubber cable, which consists of, from the inside out, 3 insulated wire cores, a filling layer 4, a cable core wrapping tape 5, a shielding layer 6, a single-mode optical fiber unit 7, a buffer layer 8, a fluorocarbon protective layer 9, a hydrophobic and impermeable interlayer 10, and a corrosion-resistant and high temperature resistant sheath layer 11.

[0043] Insulated core: Conductor 1 has a tin plating thickness of 0.05mm and a stranding pitch of 10 times the diameter of conductor 1, with a diameter of 1.5mm; Conductor anti-corrosion primer 2 has a thickness of 0.01mm; Insulation layer 3 has a thickness of 0.8mm and a formula by weight of 100 parts methyl vinyl silicone rubber, 15 parts fluorosilicone resin, 20 parts modified nano silicon carbide, 15 parts fumed silica, 40 parts acid-resistant filler, 10 parts high-temperature resistant filler, 2 parts crosslinking agent, 1 part antioxidant, and 1 part silane coupling agent; The three insulated cores are stranded into a cable with a stranding pitch of 12 times the outer diameter of the cable.

[0044] Filler layer 4: 0.6mm diameter ceramicized silicone rubber filler rope + silicone resin / nano silica 8:2 sealant for synergistic filling; Cable core wrapping tape 5: ceramicized silicone rubber tape, wrapping overlap rate 50%, thickness after wrapping 0.2mm.

[0045] Shielding layer 6: Braided from silver-plated copper wire with a braiding density of 90%, a silver plating layer thickness of 0.03mm, and a copper wire diameter of 0.1mm; Fiber unit 7: Single-mode fiber (9μm / 125μm), with an external coating layer thickness of 0.1mm and an acid-resistant buffer sleeve thickness of 0.2mm. Fiber unit 7 and shielding layer 6 are fixed together by ceramicized silicone rubber tape wound at 5cm intervals.

[0046] Buffer layer 8: made of ceramicized silicone rubber tape with a wrapping overlap rate of 50% and a thickness of 0.3mm after wrapping; Fluorocarbon protective layer 9: a dense coating formed by spraying polytetrafluoroethylene emulsion with a thickness of 0.05mm, dried at 120℃ for 10min.

[0047] Hydrophobic and impermeable interlayer 10: Fluorocarbon micro-nano coating + aramid nonwoven fabric composite layer, thickness 0.08mm, aramid nonwoven fabric is impregnated with fluorosilicone resin; Corrosion-resistant and high-temperature resistant sheath layer 11: thickness 1.5mm, the formula by weight is 100 parts fluorosilicone rubber, 30 parts methyl vinyl silicone rubber, 15 parts modified hexagonal boron nitride, 10 parts nano tin oxide, 5 parts expandable graphite, 50 parts acid-resistant filler, 3 parts crosslinking agent, 2 parts anti-aging agent, and 1 part lubricant.

[0048] The processing technology is carried out according to the above steps S1-S6. The mixing temperature of the rubber compound for the insulation layer 3 is 70℃, the vacuum degree is 0.08MPa, and the vulcanization temperature is 160℃. The mixing temperature of the rubber compound for the corrosion-resistant and high-temperature resistant sheath layer 11 is 80℃, and the vulcanization temperature is 170℃.

[0049] The cables prepared in Examples 1-2 were subjected to performance tests, with conventional multi-core silicone rubber cables used as a control group. The test results are shown in the table below:

[0050] .

[0051] The test results show that the cable prepared by this invention is significantly better than the control group in terms of temperature resistance, strong acid resistance, mechanical properties, and electrical properties. The cable structure is stable, and the optical fiber unit 7 has excellent transmission performance in extreme environments, fully meeting the requirements for use in extreme environments with strong acid and high temperature.

[0052] As can be seen from the above test results, the acid-resistant and high-temperature resistant silicone rubber cables prepared in Examples 1-2 of this invention are significantly superior to existing conventional multi-core silicone rubber cables in terms of temperature resistance, acid resistance, mechanical properties, and electrical properties. The cable structure is stable, and the core wires do not shift or wear. The newly added optical fiber unit 7 exhibits excellent optical transmission stability in extreme environments. The filling layer, cable wrapping tape, and buffer layer further enhance the cable's anti-permeability and mechanical properties, meeting the integrated needs of multi-core power transmission and optical communication under extreme environments of strong acid and high temperature.

[0053] Based on the above-described preferred embodiments of the present invention, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A strong acid resistant, high temperature resistant silicone rubber cable, characterized by, From the inside out, the structure includes a multi-core insulated wire core, a filling layer (4), a cable core wrapping tape (5), a shielding layer (6), an optical fiber unit (7), a buffer layer (8), a fluorocarbon protective layer (9), and a corrosion-resistant and high-temperature resistant sheath layer (11). The conductor (1) of the multi-core insulated wire core is provided with a conductor anti-corrosion base coating (2). A hydrophobic and anti-permeability interlayer (10) is provided between the fluorocarbon protective layer (9) and the corrosion-resistant and high-temperature resistant sheath layer (11). The insulation layer (3) and the corrosion-resistant and high-temperature resistant sheath layer (11) of the insulated wire core are both made of modified silicone rubber material. The filling layer (4), the cable core wrapping tape (5), and the buffer layer (8) are all made of the same material as ceramicized silicone rubber. The insulating layer (3) is prepared using high-temperature and strong acid resistant modified silicone rubber, and the formula by weight is as follows: 100 parts of methyl vinyl silicone rubber, 15-20 parts of fluorosilicone resin, 20-30 parts of modified nano silicon carbide, 15-25 parts of fumed silica, 40-50 parts of acid-resistant filler, 10-15 parts of high-temperature resistant filler, 2-4 parts of crosslinking agent, 1-2 parts of antioxidant, and 1-3 parts of silane coupling agent; the methyl vinyl silicone rubber has a vinyl content of 0.5-1.0% and a viscosity of 10000-20000 mpa.s, and the modified nano silicon carbide is modified by 3-aminopropyltriethoxysilane and aminosulfonic acid, with a particle size of 0.05-0.1 μm; The hydrophobic and impermeable interlayer (10) is a composite layer of fluorocarbon micro-nano coating and aramid nonwoven fabric with a thickness of 0.08-0.12 mm. The aramid nonwoven fabric is impregnated with fluorosilicone resin and has a porosity of ≤5%. The corrosion-resistant and high-temperature resistant sheath layer (11) is made of reinforced modified silicone rubber and has the following formula by weight: 100 parts of fluorosilicone rubber, 30-40 parts of methyl vinyl silicone rubber, 15-25 parts of modified hexagonal boron nitride, 10-15 parts of nano tin oxide, 5-10 parts of expandable graphite, 50-60 parts of acid-resistant filler, 3-5 parts of crosslinking agent, 2-3 parts of anti-aging agent, and 1-2 parts of lubricant.

2. The strong acid resistant high temperature resistant silicone rubber cable according to claim 1, characterized in that, The multi-core insulated wire has 2 or more cores. Each insulated wire core includes a conductor (1), a conductor anti-corrosion base coating (2), and an insulation layer (3). The conductor (1) is made of tin-plated oxygen-free copper wire stranded together. The tin plating layer is 0.05-0.1 mm thick, the oxygen-free copper wire has a purity of ≥99.99%, and the stranding pitch is 10-15 times the diameter of the conductor (1). The conductor anti-corrosion base coating (2) is an organosilane anti-corrosion coating with a thickness of 0.01-0.03 mm. It is prepared by compounding γ-aminopropyltriethoxysilane with nano-titanium dioxide.

3. The strong acid resistant and high temperature resistant silicone rubber cable according to claim 1, characterized in that, The filling layer (4) is filled with ceramicized silicone rubber filling rope and high-temperature and acid-resistant sealant. The ceramicized silicone rubber filling rope has a diameter of 0.5-1.2 mm, a breaking strength of ≥3.5 MPa, a breaking elongation of ≥200%, and contains ceramicized filler and fluorosilicone modified components. The high-temperature and acid-resistant sealant is prepared by mixing silicone resin and nano-silica at a mass ratio of 8:

2. The cable core wrapping tape (5) is a ceramicized silicone rubber tape with a wrapping overlap rate of ≥50% and a thickness of 0.2-0.3 mm after wrapping.

4. The highly acid and heat resistant silicone rubber cable according to claim 1, characterized by, The shielding layer (6) is made of silver-plated copper wire with a braiding density of ≥90%, a silver plating layer thickness of 0.03-0.05mm, and a copper wire diameter of 0.1-0.15mm. The optical fiber unit (7) is located between the shielding layer (6) and the buffer layer (8), and is made of high-temperature and strong acid resistant single-mode or multi-mode optical fiber. The optical fiber is covered with a coating layer and an acid-resistant buffer sleeve in sequence. The sleeve is filled with high-temperature and acid-resistant sealant. The optical fiber unit (7) and the shielding layer (6) are fixed by ceramicized silicone rubber tape at a spacing of 5-10cm.

5. The acid-resistant and high-temperature-resistant silicone rubber cable according to claim 1, characterized in that, The buffer layer (8) is made of ceramicized silicone rubber tape wrapped with an overlap rate of ≥50% and a thickness of 0.3-0.5mm after wrapping. It has a long-term temperature resistance of ≥300℃ and a short-term temperature resistance of ≥350℃ and can resist corrosion of 50% concentration strong acid. The fluorocarbon protective layer (9) is a dense coating prepared by spraying polytetrafluoroethylene emulsion with a thickness of 0.05-0.1mm and dried at 120-140℃ for 10-15min.

6. The highly acid and heat resistant silicone rubber cable according to claim 1, characterized by, The modified hexagonal boron nitride is modified with dodecyltrimethoxysilane and has a particle size of 0.1-0.2 μm; the acid-resistant filler is a mixture of modified nano-calcium carbonate and cerium carbonate in a mass ratio of 2:1, which is modified by soaking in nitric acid aqueous solution and has a particle size of 0.05-0.1 μm; the corrosion-resistant and high-temperature resistant sheath layer (11) has a thickness of 1.5-2.0 mm and is prepared by sulfurization at 170-190℃ and 0.4-0.6 MPa for 20-25 min.

7. A process for the processing of a high-acid-resistant high-temperature-resistant silicone rubber cable according to any one of claims 1 to 6, characterized in that Includes the following steps: S1. Conductor (1) preparation: oxygen-free copper wire is drawn, inspected and stranded, tin-plated and coated with conductor anti-corrosion base coating (2), and dried to obtain finished conductor (1); S2, Insulation layer (3) extrusion: Prepare insulation layer (3) rubber material according to the formula, extrude it on the outside of the finished conductor (1) after vacuum kneading, vulcanize and cool to obtain insulated wire core, and use it after passing the inspection; S3. Cable forming process: Twist 2 or more insulated wire cores into a cable with a twisting pitch of 12-18 times the outer diameter of the cable. Fill the gap between the core wires with ceramicized silicone rubber filler rope and inject high temperature and acid resistant sealant to form a filler layer (4). Wrap the cable core with cable wrapping tape (5) to obtain the cable core. S4. Shielding and fiber optic laying: Silver-plated copper wire is braided on the outside of the cable core to form a shielding layer (6), fiber optic units (7) are laid and fixed with ceramicized silicone rubber tape, and a buffer layer (8) is formed by wrapping the ceramicized silicone rubber tape. S5. Preparation of protective layer: Spray polytetrafluoroethylene emulsion on the outside of the buffer layer (8) to form a fluorocarbon protective layer (9) and dry it, composite hydrophobic and impermeable interlayer (10), extrude corrosion resistant and high temperature resistant sheath layer (11) rubber material and vulcanize and cool it. S6. Finished product processing: The cable is sealed at the ends and its performance is tested. After passing the test, it is put into storage.

8. The process of claim 7, wherein, The preparation conditions for the insulating layer (3) rubber in step S2 are as follows: mixing for 30-60 minutes at 70-90℃ and vacuum degree of 0.08-0.10MPa, adding crosslinking agent, antioxidant and silane coupling agent and continuing to mix for 20-30 minutes; extrusion temperature of 120-140℃, vulcanization conditions of 160-180℃ and 0.3-0.5MPa for 15-20 minutes; the extrusion temperature of the corrosion-resistant and high-temperature resistant sheath layer (11) rubber in step S5 is 130-150℃, the cable end is sealed with a fluorosilicone rubber sealing sleeve, and the sealing sleeve is bonded to the corrosion-resistant and high-temperature resistant sheath layer (11) and conductor (1) with a high-temperature resistant and acid-resistant adhesive.

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