Flame-retardant high-pressure steel wire braided rubber hose and production process thereof

Abstract

The application relates to the technical field of high-pressure rubber pipes, and particularly discloses a flame-retardant high-pressure steel wire braided rubber pipe and a production process thereof. The flame-retardant high-pressure steel wire braided rubber pipe comprises an inner rubber layer, a steel wire braided layer which is arranged outside the inner rubber layer in a wrapping mode, and an outer rubber layer which is arranged outside the steel wire braided layer in a wrapping mode; the inner rubber layer is made of a nitrile rubber sheet; the outer rubber layer is mainly made of raw materials in the following proportions by weight: nitrile rubber, silicone rubber, carbon black, dioctyl phthalate, paraffin oil, zinc oxide, fatty acid, accelerator, anti-aging agent and flame retardant; the flame retardant is composed of polytetrafluoroethylene micro powder, organic aerogel and composite material in a mass ratio of (15-20):(3-5):(7-12). The flame-retardant high-pressure steel wire braided rubber pipe has the advantages of good flame-retardant performance and high-temperature resistance.

Description

A flame-retardant high-pressure steel wire braided hose and its manufacturing process Technical Field

[0001] This application relates to the field of high-pressure hose technology, and more specifically, to a flame-retardant high-pressure steel wire braided hose and its manufacturing process. Background Technology

[0002] High-pressure steel wire braided rubber hoses are generally composed of a liquid-resistant synthetic rubber inner layer, a middle rubber layer, several layers of steel wire braiding reinforcement, and an outer rubber layer with excellent weather resistance. They have the advantages of corrosion resistance, high strength, and high pressure resistance, and are widely used in the industrial field.

[0003] High-pressure steel wire braided hoses are mainly used in hydraulic supports for mines, oilfield extraction, engineering construction, hoisting and transportation, metallurgical forging, mining equipment, ships, injection molding machinery, various machine tools, and mechanized and automated hydraulic systems in various industrial fields. They can transport petroleum-based liquids (such as mineral oil, hydraulic oil, lubricating oil, etc.), water-based liquids (such as emulsified oil, oil-water emulsion, water, etc.), and gases under certain pressure and temperature conditions, and are of great significance to the transmission systems in industrial production processes.

[0004] Currently, the operating temperature of conventional high-pressure steel wire braided rubber hoses is -40℃ to 100℃. They are not well-suited for high-temperature environments with heat sources or heat radiation, such as oilfield well control operations, metal smelting, and chemical industries. Under high-temperature conditions, the outer layer of high-pressure steel wire braided rubber hoses is easily damaged by heat and can burn, leading to danger. Summary of the Invention

[0005] In order to improve the fire resistance and flame retardant properties of high-pressure steel wire braided rubber hoses, this application provides a flame-retardant high-pressure steel wire braided rubber hose and its manufacturing process.

[0006] In the first aspect, this application provides a flame-retardant high-pressure steel wire braided hose, which adopts the following technical solution:

[0007] A flame-retardant high-pressure steel wire braided hose includes an inner rubber layer, a steel wire braided layer covering the inner rubber layer, and an outer rubber layer covering the steel wire braided layer. The inner rubber layer is made of nitrile rubber sheet, and the outer rubber layer is mainly made of the following raw materials in parts by weight: 70-90 parts nitrile rubber, 35-50 parts silicone rubber, 10-15 parts carbon black, 5-10 parts dioctyl phthalate, 5-10 parts paraffin oil, 5-7 parts zinc oxide, 1-3 parts fatty acid, 0.5-1 part accelerator, 0.5-1 part antioxidant, and 20-25 parts flame retardant. The flame retardant is composed of polytetrafluoroethylene micro powder, organic aerogel, and composite material in a mass ratio of (15-20):(3-5):(7-12).

[0008] The composite material is prepared by a method comprising the following steps:

[0009] 1) Benzocyclobutene and nanosheet filler are blended at 200-260℃ to obtain intermediate material;

[0010] 2) The intermediate material and aluminum hydroxide are mixed evenly, extruded, and then powdered to obtain the final product.

[0011] By adopting the above technical solution, using a composite structure of an inner rubber layer, a steel wire braided layer, and an outer rubber layer, the structural strength of the hose can be enhanced, and its pressure resistance improved. The outer rubber layer is made from a blend of nitrile rubber and silicone rubber, with the addition of dioctyl phthalate, paraffin oil, fatty acids, accelerators, and antioxidants to promote compatibility between components and to provide plasticizing and stabilizing effects, resulting in good isotropy of the outer rubber layer. Zinc oxide and carbon black components act as fillers, enhancing the mechanical and thermal insulation properties of the outer rubber layer.

[0012] Furthermore, flame retardants are added to the raw materials of the outer adhesive layer. Polytetrafluoroethylene (PTFE) micropowder can undergo fibrosis during combustion, forming a fibrous network structure, which provides excellent flame retardancy and anti-dripping properties. Simultaneously, organic aerogels and composite materials can be embedded within the fibrous network structure formed during the PTFE micropowder fibrosis process. The porous characteristic size effect of the organic aerosol can reduce the thermal conductivity and slow down heat transfer. During combustion, the rearranged polymer resin formed from benzocyclobutene in the composite material can synergistically work with the organic aerosol to capture free radicals, interrupting the combustion reaction process. It also undergoes polymer charring, forming a non-combustible coke layer. The thermal decomposition of aluminum hydroxide causes the coke layer to form a micro-nano porous structure, further reducing the thermal conductivity. Moreover, the nanosheet filler is uniformly distributed within the coke layer, synergistically acting as a physical barrier, providing excellent heat insulation and oxygen barrier properties, thus achieving a very good flame retardant effect.

[0013] Preferably, the nanosheet filler is at least one of alumina nanosheets, boron nitride nanosheets, molybdenum disulfide nanosheets, and graphite nanosheets.

[0014] By adopting the above technical solutions, the composition of nanosheet fillers is optimized and adjusted, the thermal insulation structure between the nanosheet fillers and the coke layer is improved, and better flame retardancy and thermal stability are obtained.

[0015] Preferably, the nanosheet filler is composed of boron nitride nanosheets and graphite nanosheets in a mass ratio of (10-15):(3-7).

[0016] By adopting the above technical solution, the composition ratio of nanosheet fillers was further tested and screened to balance the heat resistance and flame retardant properties of nanosheet fillers, resulting in better overall performance of the coke layer and enabling it to stably play a flame retardant role in high-temperature environments.

[0017] Preferably, in step 1), the mass ratio of benzocyclobutene to nanosheet filler is (5-6.5):1.

[0018] By adopting the above technical solution, the mass ratio of benzocyclobutene to nanosheet filler is optimized and adjusted, improving the molecular coupling state of benzocyclobutene and enhancing the film-forming and bonding properties of the polymer. This results in better compatibility of the nanosheet filler within the polymer, reducing the likelihood of agglomeration. Furthermore, a suitable proportion of nanosheet filler can increase the rigid volume of the polymer, improving its thermal stability and insulation properties.

[0019] Preferably, the organic aerogel is one of polyimide aerogel, polyurethane aerogel, and polyamide aerogel.

[0020] By adopting the above technical solutions, the types and compositions of organic aerogels were tested and screened. Polyimide aerogel, polyurethane aerogel and polyamide aerogel showed better flame retardant and char-forming effects, and the resulting aerogel structures had low thermal conductivity, resulting in better overall heat insulation and flame retardant effects.

[0021] More preferably, the organic aerogel is a polyimide aerogel.

[0022] Preferably, the mass ratio of the flame retardant to the nitrile rubber is (0.22-0.26):1.

[0023] While adding more flame retardant can enhance the flame retardant effect of the outer rubber layer to some extent by adopting the above technical solution, it will also have an adverse effect on the mechanical properties of the outer rubber layer, making it prone to cracking, delamination, and stress fatigue. On the other hand, adding too little flame retardant will not achieve the corresponding flame retardant effect and may even cause burning holes in some areas of the outer rubber layer, thus reducing the heat insulation and flame retardant performance of the outer rubber layer. Therefore, it is necessary to optimize and adjust the mass ratio of flame retardant to nitrile rubber to balance the mechanical properties and flame retardant properties of the outer rubber layer.

[0024] Preferably, the raw material of the outer adhesive layer further includes 3.5-6 parts by weight of hyperbranched polyester.

[0025] By adopting the above technical solution and adding hyperbranched polyester, the steric hindrance and bridging effects of hyperbranched polyester molecules are utilized to form an amorphous core and a crystalline shell within the outer adhesive layer structure. On the one hand, this can capture free radicals and reduce chain reactions during combustion. On the other hand, the high degree of cross-linking enhances the thermal stability of the outer adhesive layer, reduces combustion dripping, improves the structural state of the char layer, and further enhances the heat insulation and flame retardant effect of the outer adhesive layer.

[0026] Secondly, this application provides a manufacturing process for flame-retardant high-pressure steel wire braided hoses, employing the following technical solution:

[0027] A manufacturing process for flame-retardant high-pressure steel wire braided hoses includes the following steps:

[0028] S1: After vulcanizing the nitrile rubber sheet, it is pressed out to obtain the inner rubber tube, and then a steel wire braided layer is woven on the outside of the inner rubber tube.

[0029] S2: Take the following ingredients in the formula of the outer rubber layer: nitrile rubber, silicone rubber, carbon black, dioctyl phthalate, paraffin oil, zinc oxide, fatty acid, accelerator, antioxidant, and flame retardant, mix them thoroughly, and vulcanize them to obtain the outer rubber layer sheet.

[0030] S3: The outer adhesive layer film is extruded and coated onto the surface of the steel wire braided layer.

[0031] By adopting the above technical solution, a steel wire braided layer and an outer rubber layer are wrapped around the outside of the inner rubber hose, providing excellent reinforcement and protection to ensure the material conveying inside the inner hose. Furthermore, the outer rubber layer, made from a compound of multiple components, exhibits superior thermal stability, and with the addition of flame retardants, it achieves excellent heat insulation and flame retardant effects, enabling it to operate stably for extended periods in high-temperature and high-heat radiation environments.

[0032] Preferably, in steps S1 and S2, the vulcanization conditions are 150-180℃ and the vulcanization time is 50-70min.

[0033] By adopting the above technical solution and optimizing and adjusting the vulcanization process, the components of the inner and outer rubber layers form a stable three-dimensional network structure of macromolecules, thereby improving the mechanical properties of both layers. Furthermore, vulcanization of the outer rubber layer enhances the compatibility between other components and the rubber components, resulting in a more uniform and stable outer rubber layer.

[0034] Preferably, step S2 further includes the step of adding hyperbranched polyester.

[0035] In summary, this application has the following beneficial effects:

[0036] 1. This application adds flame retardant to the raw materials of the outer adhesive layer. When polytetrafluoroethylene micro powder is burned, it undergoes fibrosis to form a fibrous network structure. Organic aerosols and composite materials are distributed and embedded in the fibrous network structure. During the combustion process, a special coke layer structure is formed, which can play a very good role in heat insulation and oxygen isolation, and has better flame retardant performance.

[0037] 2. In this application, the types and composition of nanosheet fillers and organic aerosols, as well as the mass ratio of flame retardant to nitrile rubber, are optimized and adjusted. Furthermore, hyperbranched polyester is added to further improve the flame retardant and mechanical properties of the outer adhesive layer.

[0038] 3. The flame-retardant high-pressure steel wire braided hose produced using the manufacturing process of this application has excellent flame-retardant properties, can work stably for a long time in high-temperature environments, and provides excellent protection for the inner hose. Detailed Implementation

[0039] The present application will be further described in detail below with reference to the embodiments.

[0040] Unless otherwise specified, the raw materials used in the embodiments and comparative examples of this application are all commercially available.

[0041] Example

[0042] Example 1

[0043] The flame-retardant high-pressure steel wire braided hose of this embodiment includes an inner rubber layer, a steel wire braided layer covering the inner rubber layer, and an outer rubber layer covering the steel wire braided layer. The inner rubber layer is made of nitrile rubber sheet. The steel wire braided layer has two layers, and a middle rubber layer is provided between the two steel wire braided layers. The middle rubber layer is made of nitrile rubber sheet.

[0044] The nitrile rubber sheet of this embodiment is made by intensive mixing of the following raw materials by weight: 100 kg nitrile rubber, 30 kg carbon black, 5 kg zinc oxide, 1 kg stearic acid, 0.5 kg diphenylamine, and 0.3 kg N-cyclohexyl-2-benzothiazole sulfenamide.

[0045] The outer adhesive layer of this embodiment is made from the following raw materials by weight: 90 kg of nitrile rubber, 35 kg of silicone rubber, 10 kg of carbon black, 10 kg of dioctyl phthalate, 5 kg of paraffin oil, 5 kg of zinc oxide, 3 kg of fatty acid, 0.5 kg of accelerator, 1 kg of antioxidant, and 20 kg of flame retardant.

[0046] The flame retardant is composed of polytetrafluoroethylene micro powder, organic aerogel, and composite material in a mass ratio of 20:3:12.

[0047] The accelerator is dibenzothiazole disulfide. The antioxidant is antioxidant 4010NA. The average particle size of the polytetrafluoroethylene micropowder is 150 μm, and the molecular weight is 200,000. The organic aerogel is polym-phenylenediamine aerogel.

[0048] The composite material in this embodiment is prepared by a method including the following steps:

[0049] 1) Benzocyclobutene and graphite nanosheets were placed in a blender at a mass ratio of 10:1 and blended at 200°C to obtain an intermediate material.

[0050] 2) Mix the intermediate material and aluminum hydroxide in an extruder at a mass ratio of 30:1 until homogeneous. After co-extrusion and powdering, the product is obtained.

[0051] The manufacturing process of the flame-retardant high-pressure steel wire braided hose in this embodiment includes the following steps:

[0052] S1: The nitrile rubber sheet is vulcanized on a flat vulcanizing machine at a vulcanization temperature of 180℃ for 50 minutes. The vulcanized nitrile rubber sheet is then extruded into an inner rubber tube with a diameter of φ25mm in an extrusion machine. The inner rubber tube is then braided with two layers of steel wire braid on a braiding machine. A middle rubber layer is wrapped between the two layers of steel wire braid. Both layers of steel wire braid are 3×3 braided with a braiding angle of 52 degrees.

[0053] S2: Take the following ingredients in the outer rubber layer formula: nitrile rubber, silicone rubber, carbon black, dioctyl phthalate, paraffin oil, zinc oxide, fatty acid, accelerator, antioxidant, and flame retardant, mix them in an internal mixer, and then vulcanize them on a flat vulcanizing machine to obtain the outer rubber layer sheet. The vulcanization temperature is 180℃ and the vulcanization time is 50min.

[0054] S3: The outer rubber layer is extruded using an extruder and coated onto the surface of the outermost steel wire braided layer.

[0055] Example 2

[0056] The flame-retardant high-pressure steel wire braided hose of this embodiment includes an inner rubber layer, a steel wire braided layer covering the inner rubber layer, and an outer rubber layer covering the steel wire braided layer. The inner rubber layer is made of nitrile rubber sheet. The steel wire braided layer has two layers, and a middle rubber layer is provided between the two steel wire braided layers. The middle rubber layer is made of nitrile rubber sheet.

[0057] The nitrile rubber sheet of this embodiment is made by intensive mixing of the following raw materials by weight: 100 kg nitrile rubber, 30 kg carbon black, 5 kg zinc oxide, 1 kg stearic acid, 0.5 kg diphenylamine, and 0.3 kg N-cyclohexyl-2-benzothiazole sulfenamide.

[0058] The outer adhesive layer of this embodiment is made from the following raw materials by weight: 70 kg of nitrile rubber, 50 kg of silicone rubber, 15 kg of carbon black, 5 kg of dioctyl phthalate, 10 kg of paraffin oil, 7 kg of zinc oxide, 1 kg of fatty acid, 1 kg of accelerator, 0.5 kg of antioxidant, and 25 kg of flame retardant.

[0059] The flame retardant is composed of polytetrafluoroethylene micro powder, organic aerogel, and composite material in a mass ratio of 20:3:12.

[0060] The accelerator is dibenzothiazole disulfide. The antioxidant is antioxidant 4010NA. The average particle size of the polytetrafluoroethylene micropowder is 150 μm, and the molecular weight is 200,000. The organic aerogel is polym-phenylenediamine aerogel.

[0061] The composite material in this embodiment is prepared by a method including the following steps:

[0062] 1) Benzocyclobutene and graphite nanosheets were placed in a blender at a mass ratio of 10:1 and blended at 260°C to obtain an intermediate material.

[0063] 2) Mix the intermediate material and aluminum hydroxide in an extruder at a mass ratio of 30:1 until homogeneous. After co-extrusion and powdering, the product is obtained.

[0064] The difference between the production process of the flame-retardant high-pressure steel wire braided hose in this embodiment and that in embodiment 1 is that in steps S1 and S2, the vulcanization conditions are 150°C and the vulcanization time is 70 min, while the rest are the same as in embodiment 1.

[0065] Example 3

[0066] The flame-retardant high-pressure steel wire braided hose of this embodiment includes an inner rubber layer, a steel wire braided layer covering the inner rubber layer, and an outer rubber layer covering the steel wire braided layer. The inner rubber layer is made of nitrile rubber sheet. The steel wire braided layer has two layers, and a middle rubber layer is provided between the two steel wire braided layers. The middle rubber layer is made of nitrile rubber sheet.

[0067] The nitrile rubber sheet of this embodiment is made by intensive mixing of the following raw materials by weight: 100 kg nitrile rubber, 30 kg carbon black, 5 kg zinc oxide, 1 kg stearic acid, 0.5 kg diphenylamine, and 0.3 kg N-cyclohexyl-2-benzothiazole sulfenamide.

[0068] The outer adhesive layer of this embodiment is made from the following raw materials by weight: 85 kg of nitrile rubber, 40 kg of silicone rubber, 12 kg of carbon black, 8.5 kg of dioctyl phthalate, 7 kg of paraffin oil, 6 kg of zinc oxide, 2 kg of fatty acid, 0.75 kg of accelerator, 0.8 kg of antioxidant, and 22.5 kg of flame retardant.

[0069] The flame retardant is composed of polytetrafluoroethylene micro powder, organic aerogel, and composite material in a mass ratio of 20:3:12.

[0070] The accelerator is dibenzothiazole disulfide. The antioxidant is antioxidant 4010NA. The average particle size of the polytetrafluoroethylene micropowder is 150 μm, and the molecular weight is 200,000. The organic aerogel is polym-phenylenediamine aerogel.

[0071] The composite material in this embodiment is prepared by a method including the following steps:

[0072] 1) Benzocyclobutene and graphite nanosheets were placed in a blender at a mass ratio of 10:1 and blended at 230°C to obtain an intermediate material.

[0073] 2) Mix the intermediate material and aluminum hydroxide in an extruder at a mass ratio of 30:1 until homogeneous. After co-extrusion and powdering, the product is obtained.

[0074] The difference between the production process of the flame-retardant high-pressure steel wire braided hose in this embodiment and that in embodiment 1 is that in steps S1 and S2, the vulcanization conditions are 170°C and the vulcanization time is 60 min, while the rest are the same as in embodiment 1.

[0075] Example 4

[0076] The difference between the flame-retardant high-pressure steel wire braided hose of this embodiment and that of embodiment 3 is that the flame retardant is composed of polytetrafluoroethylene micro powder, organic aerogel, and composite material in a mass ratio of 15:5:7, while the rest is the same as that of embodiment 3.

[0077] The preparation method of the composite material in this embodiment is the same as that in Example 3.

[0078] The production process of the flame-retardant high-pressure steel wire braided hose in this embodiment is the same as that in Embodiment 3.

[0079] Example 5

[0080] The difference between the flame-retardant high-pressure steel wire braided hose of this embodiment and that of embodiment 3 is that the flame retardant is composed of polytetrafluoroethylene micro powder, organic aerogel, and composite material in a mass ratio of 18.5:3.6:9, while the rest is the same as that of embodiment 3.

[0081] The preparation method of the composite material in this embodiment is the same as that in Example 3.

[0082] The production process of the flame-retardant high-pressure steel wire braided hose in this embodiment is the same as that in Embodiment 3.

[0083] Example 6

[0084] The difference between the flame-retardant high-pressure steel wire braided hose of this embodiment and that of embodiment 5 is that the nanosheet filler is composed of alumina nanosheets and molybdenum disulfide nanosheets in a mass ratio of 10:3, while the rest is the same as that of embodiment 5.

[0085] The preparation method of the composite material in this embodiment is the same as that in Example 5.

[0086] The production process of the flame-retardant high-pressure steel wire braided hose in this embodiment is the same as that in Embodiment 5.

[0087] Example 7

[0088] The difference between the flame-retardant high-pressure steel wire braided hose of this embodiment and that of embodiment 5 is that the nanosheet filler is composed of boron nitride nanosheets and graphite nanosheets in a mass ratio of 10:3, while the rest is the same as that of embodiment 5.

[0089] The preparation method of the composite material in this embodiment is the same as that in Example 5.

[0090] The production process of the flame-retardant high-pressure steel wire braided hose in this embodiment is the same as that in Embodiment 5.

[0091] Example 8

[0092] The difference between the flame-retardant high-pressure steel wire braided hose of this embodiment and that of embodiment 5 is that the nanosheet filler is composed of boron nitride nanosheets and graphite nanosheets in a mass ratio of 15:7, while the rest is the same as that of embodiment 5.

[0093] The preparation method of the composite material in this embodiment is the same as that in Example 5.

[0094] The production process of the flame-retardant high-pressure steel wire braided hose in this embodiment is the same as that in Embodiment 5.

[0095] Example 9

[0096] The difference between the flame-retardant high-pressure steel wire braided hose of this embodiment and that of Example 8 is that the mass ratio of benzocyclobutene to nanosheet filler is 5:1, while the rest is the same as that of Example 8.

[0097] The preparation method of the composite material in this embodiment is the same as that in Example 8.

[0098] The production process of the flame-retardant high-pressure steel wire braided hose in this embodiment is the same as that in embodiment 8.

[0099] Example 10

[0100] The difference between the flame-retardant high-pressure steel wire braided hose of this embodiment and that of Example 8 is that the mass ratio of benzocyclobutene to nanosheet filler is 6.5:1, while the rest is the same as that of Example 8.

[0101] The preparation method of the composite material in this embodiment is the same as that in Example 8.

[0102] The production process of the flame-retardant high-pressure steel wire braided hose in this embodiment is the same as that in embodiment 8.

[0103] Example 11

[0104] The difference between the flame-retardant high-pressure steel wire braided hose of this embodiment and that of Example 10 is that the organic aerogel is a polyimide aerogel, while the rest is the same as that of Example 10.

[0105] The preparation method of the composite material in this embodiment is the same as that in Example 10.

[0106] The production process of the flame-retardant high-pressure steel wire braided hose in this embodiment is the same as that in Embodiment 10.

[0107] Example 12

[0108] The difference between the flame-retardant high-pressure steel wire braided hose of this embodiment and that of Embodiment 11 is that the outer rubber layer also contains 3.5 kg of hyperbranched polyester, model HyPer H102, while the rest is the same as that of Embodiment 11.

[0109] The preparation method of the composite material in this embodiment is the same as that in Example 11.

[0110] The production process of the flame-retardant high-pressure steel wire braided hose in this embodiment is the same as that in Embodiment 11.

[0111] Example 13

[0112] The difference between the flame-retardant high-pressure steel wire braided hose of this embodiment and that of Embodiment 11 is that the outer rubber layer also contains 6 kg of hyperbranched polyester, model HyPer H102, while the rest is the same as that of Embodiment 11.

[0113] The preparation method of the composite material in this embodiment is the same as that in Example 11.

[0114] The production process of the flame-retardant high-pressure steel wire braided hose in this embodiment is the same as that in Embodiment 11.

[0115] Comparative Example

[0116] Comparative Example 1

[0117] The flame-retardant high-pressure steel wire braided hose of this comparative example includes an inner rubber layer, a steel wire braided layer covering the inner rubber layer, and an outer rubber layer covering the steel wire braided layer. The inner rubber layer is made of nitrile rubber sheet. The steel wire braided layer consists of two layers, with a middle rubber layer between the two steel wire braided layers. The middle rubber layer is also made of nitrile rubber sheet.

[0118] The nitrile rubber sheet of this comparative example was made by internal mixing of the following raw materials by weight: 100 kg nitrile rubber, 30 kg carbon black, 5 kg zinc oxide, 1 kg stearic acid, 0.5 kg diphenylamine, and 0.3 kg N-cyclohexyl-2-benzothiazole sulfenamide.

[0119] The outer rubber layer of this comparative example is made from the following raw materials by weight: 100 kg of nitrile rubber, 45 kg of silicone rubber, 10 kg of carbon black, 10 kg of dioctyl phthalate, 5 kg of paraffin oil, 5 kg of zinc oxide, 3 kg of fatty acid, 0.5 kg of accelerator, and 1 kg of antioxidant.

[0120] The accelerator is dibenzothiazole disulfide. The antioxidant is antioxidant 4010NA.

[0121] The production process of the flame-retardant high-pressure steel wire braided hose in this comparative example is the same as that in Example 1.

[0122] Comparative Example 2

[0123] The difference between the flame-retardant high-pressure steel wire braided hose of this comparative example and Example 1 is that the flame retardant in the outer rubber layer is decabromodiphenyl ether, while the rest are the same as in Example 1.

[0124] The production process of the flame-retardant high-pressure steel wire braided hose in this comparative example is the same as that in Example 1.

[0125] Comparative Example 3

[0126] The difference between the flame-retardant high-pressure steel wire braided hose in this comparative example and Example 1 is that the flame retardant in the outer rubber layer is polytetrafluoroethylene micro powder, while the rest is the same as in Example 1.

[0127] The production process of the flame-retardant high-pressure steel wire braided hose in this comparative example is the same as that in Example 1.

[0128] Comparative Example 4

[0129] The difference between the flame-retardant high-pressure steel wire braided hose of this comparative example and Example 1 is that the flame retardant in the outer rubber layer is composed of fluororubber, organic aerogel and composite material in a mass ratio of 20:3:12, while the rest is the same as in Example 1.

[0130] The preparation method of the composite material in this comparative example is the same as that in Example 11.

[0131] The production process of the flame-retardant high-pressure steel wire braided hose in this comparative example is the same as that in Example 1.

[0132] Comparative Example 5

[0133] The difference between the flame-retardant high-pressure steel wire braided hose in this comparative example and Example 1 is that the flame retardant in the outer rubber layer is a composite material, while the rest are the same as in Example 1.

[0134] The preparation method of the composite material in this comparative example is the same as that in Example 11.

[0135] The production process of the flame-retardant high-pressure steel wire braided hose in this comparative example is the same as that in Example 1.

[0136] Comparative Example 6

[0137] The difference between the flame-retardant high-pressure steel wire braided hose in this comparative example and Example 1 is that the flame retardant in the outer rubber layer is an organic aerogel, while the rest is the same as in Example 1.

[0138] The production process of the flame-retardant high-pressure steel wire braided hose in this comparative example is the same as that in Example 1.

[0139] Performance testing

[0140] Detection methods

[0141] Flame-retardant high-pressure steel wire braided hoses from Examples 1-13 and Comparative Examples 1-6 were tested for flame retardant performance according to the national standard GB / T 2406.2-2009 and the UL-94 flame retardant rating test. The test results are shown in Table 1.

[0142] Table 1. Flame retardant performance test data of flame retardant high-pressure steel wire braided hoses in Examples 1-13 and Comparative Examples 1-6

[0143] Serial Number Limiting Oxygen Index (%) UL-94 Flame Retardant Rating Example 1 29.1V-1 Example 2 32.5V-1 Example 3 33.2V-1 Example 4 32.9V-1 Example 5 34.6V-0 Example 6 35.8V-0 Example 7 37.3V-0 Example 8 36.7V-0 Example 9 38.5V-0 Example 10 39.3V-0 Example 11 42.6V-0 Example 12 45.5V-0 Example 13 46.9V-0 Comparative Example 1 17.3 Stepless F Comparative Example 2 25.9V-2 Comparative Example 3 21.8V-2 Comparative Example 4 28.5V-2 Comparative Example 5 23.7V-2 Comparative Example 6 20.2V-2 surface

[0144] Analysis of Examples 1-3 and Comparative Examples 1-2, combined with Table 1, shows that this application uses a compound of polytetrafluoroethylene (PTFE) micropowder, organic aerogel, and composite material as a flame retardant. When the outer adhesive layer is eroded by high-temperature flames, PTFE can form a fibrous network structure. Simultaneously, the composite material and organic aerogel dispersed within the fibrous network structure form a coke layer with a special porous structure, providing excellent heat insulation and oxygen barrier properties, significantly enhancing the flame retardant performance of the hose. It can be seen that the limiting oxygen index of Example 3 reaches 33.2%, and the flame retardant rating is V-1, enabling stable operation in high-temperature environments. Furthermore, analysis shows that Comparative Example 1, without the addition of a flame retardant, exhibits very poor flame retardant performance. Comparative Example 2, using a conventional flame retardant, has a limiting oxygen index of 25.9 and a flame retardant rating of V-2, showing a significantly lower flame retardant performance compared to this application.

[0145] Analysis of Examples 1-3, Examples 4-5, and Comparative Examples 3-6, combined with Table 1, shows that Examples 4-5 further optimized the composition and ratio of the flame retardant, improved the microstructure of the coke layer, enhanced its heat insulation and oxygen barrier properties, and achieved better flame retardant performance. Example 5 achieved a limiting oxygen index of 34.6 and a flame retardant rating of V-0. Comparative Example 3 only added polytetrafluoroethylene (PTFE) micropowder, which, although forming a fibrous network structure and preventing combustion erosion to some extent, had limited effectiveness in blocking heat and oxygen. Comparative Example 4 used a combination of fluororubber, organic aerogel, and composite materials, which failed to form a stable and complete coke layer structure, resulting in relatively poor flame retardant performance. Comparative Examples 5 and 6 used composite materials and organic aerosols alone, respectively, leading to a significant decrease in the limiting oxygen index and a lower flame retardant rating, resulting in poor overall flame retardant performance. It can be seen that the PTFE micropowder, organic aerogel, and composite materials of this application have excellent compounding effects.

[0146] Analysis of Examples 6-8, 9-11, and 12-13, combined with Table 1, shows that further optimization and adjustment of the composition ratio of the nanosheet filler, the ratio of benzocyclobutene to the nanosheet filler, and the addition of hyperbranched polyester components further improved the flame retardant effect of the coke layer.

[0147] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A flame-retardant high-pressure steel wire braided hose, comprising an inner rubber layer, a steel wire braided layer covering the inner rubber layer, and an outer rubber layer covering the steel wire braided layer, wherein the inner rubber layer is made of acrylonitrile rubber sheet, and the outer rubber layer is mainly made of the following raw materials in parts by weight: 70-90 parts acrylonitrile rubber, 35-50 parts silicone rubber, 10-15 parts carbon black, 5-10 parts dioctyl phthalate, 5-10 parts paraffin oil, 5-7 parts zinc oxide, 1-3 parts fatty acid, 0.5-1 part accelerator, 0.5-1 part antioxidant, and 20-25 parts flame retardant; wherein the flame retardant is composed of polytetrafluoroethylene micro powder, organic aerogel, and composite material in a mass ratio of (15-20):(3-5):(7-12); characterized in that... The composite material is prepared by a method including the following steps: 1) benzocyclobutene and nanosheet filler are blended at a mass ratio of 5-6.5:1 at 200-260℃ to obtain an intermediate material; 2) the intermediate material and aluminum hydroxide are mixed evenly, extruded, and powdered to obtain the final product; the nanosheet filler is composed of alumina nanosheets and molybdenum disulfide nanosheets at a mass ratio of 10:3; or the nanosheet filler is composed of boron nitride nanosheets and graphite nanosheets at a mass ratio of (10-15):(3-7).

2. The flame-retardant high-pressure steel wire braided hose as described in claim 1, characterized in that, The nanosheet filler is composed of boron nitride nanosheets and graphite nanosheets in a mass ratio of 10:3; or the nanosheet filler is composed of boron nitride nanosheets and graphite nanosheets in a mass ratio of 15:

7.

3. The flame-retardant high-pressure steel wire braided hose as described in claim 1, characterized in that, The organic aerogel is one of polyimide aerogel, polyurethane aerogel, and polyamide aerogel.

4. The flame-retardant high-pressure steel wire braided hose as described in claim 1, characterized in that, The mass ratio of the flame retardant to the acrylonitrile rubber is (0.22-0.26):

1.

5. The flame-retardant high-pressure steel wire braided hose as described in claim 1, characterized in that, The outer adhesive layer also includes 3.5-6 parts by weight of hyperbranched polyester.

6. The method for producing flame-retardant high-pressure steel wire braided hose as described in any one of claims 1-5, characterized in that, The process includes the following steps: S1: After vulcanizing acrylonitrile rubber sheet, it is extruded to obtain an inner tube, and then a steel wire braided layer is woven around the inner tube; S2: The outer rubber sheet is prepared by mixing and vulcanizing a mixture of acrylonitrile rubber, silicone rubber, carbon black, dioctyl phthalate, paraffin oil, zinc oxide, fatty acid, accelerator, antioxidant, and flame retardant in the specified amounts; the process also includes the addition of hyperbranched polyester; S3: The outer rubber sheet is extruded and coated onto the surface of the steel wire braided layer; the accelerator is dibenzothiazole disulfide; the antioxidant is antioxidant 4010NA.

7. The method as described in claim 6, characterized in that, The vulcanization conditions are 150-180℃ and the vulcanization time is 50-70min.