A flame-retardant, abrasion-resistant rope and method of making the same

Abstract

This invention discloses a flame-retardant and wear-resistant rope and its preparation method, belonging to the field of rope processing technology. The rope includes a steel wire rope and a rubber sheath; wherein, the rubber sheath includes an inner rubber layer and an outer rubber layer; the components of the inner rubber layer include: styrene-butadiene rubber, silica, activator, reinforcing agent, antioxidant, γ-mercaptopropyltriethoxysilane, rubber adhesive, cobalt neodecanoate, sulfur, and vulcanization accelerator; the components of the outer rubber layer include: styrene-butadiene rubber, nitrile rubber, flame-retardant and wear-resistant reinforcing agent, silica, activator, reinforcing agent, antioxidant, antistatic agent, sulfur, and vulcanization accelerator; the rope has a flat cross-section design, with a width of 30-250 mm, a thickness of 10-40 mm, and a weight of 0.5-25 kg / m. The rope prepared by this invention has excellent flame-retardant, wear-resistant, and antistatic properties, and the rubber layer has strong adhesion to the steel wire, making it resistant to wear or peeling during long-term use.

Description

Technical Field

[0001] This invention belongs to the field of rope processing technology, specifically relating to a flame-retardant and wear-resistant rope and its preparation method. Background Technology

[0002] With the increasing demand for efficient, safe, and environmentally friendly equipment in modern industry and mining, the performance limitations of traditional ropes under complex working conditions are becoming increasingly apparent. This is especially true in low-temperature, high-temperature, corrosive environments, and extreme physical conditions, where their durability, safety, and functional adaptability face severe challenges. In mine operations, hoisting and lifting systems place stringent performance requirements on ropes. They must withstand enormous tensile forces and frequent dynamic loads, resist corrosive substances in vertical shafts thousands of meters deep, and achieve flexible bending within confined spaces to avoid mechanical damage caused by excessive structural rigidity. Furthermore, the prevalent methane gas and dust environments in mines place even higher demands on the electrostatic discharge (ESD) protection capabilities of the ropes. Any accumulation of static electricity could trigger an explosion, threatening the lives of workers and the stable operation of equipment.

[0003] However, existing wire rope technology has shortcomings in terms of corrosion resistance, electrostatic protection, dynamic fatigue life, and environmental adaptability. Although traditional wire ropes possess high tensile strength, they are prone to accelerated corrosion in acidic (sulfur-containing gas environments) or high-salinity environments, leading to strength reduction and increased risk of breakage. Moreover, the circular cross-section design of traditional wire ropes is prone to structural entanglement and wire breakage when bending at small radii, resulting in increased operating noise and failure frequency. Furthermore, the lack of effective flame-retardant and antistatic coating protection makes it difficult to meet the safety requirements of high-risk locations such as coal mines, copper mines, nickel mines, potash mines, rare / non-ferrous metal mines, phosphate mines, and salt mines. Although some improved ropes have introduced coating materials such as rubber and polyester, for example, Chinese patent CN103663057A discloses a tension rope for elevators, which consists of a carrier body and a coating layer. The carrier body is made of multiple carrier core wires twisted together, and the rope cross-section is designed in an elliptical shape. The coating layer material contains a self-lubricating material. The carrier core wires are high-strength steel wires, and the coating layer material is selected from polyurethane, neoprene rubber, or hydrogenated nitrile rubber. The self-lubricating material is plastic short fiber. The coating layer material fills between each carrier core wire and covers the outside of the rope. Compared with plastic-coated steel wire ropes with circular cross-sections, the rope prepared by this patent increases the contact area with the traction sheave, and the force is more uniform, thereby improving the life of the coating layer. However, its material formulation still has problems such as insufficient adhesion and poor wear resistance, which makes the coating material easy to wear or peel off during long-term use, thus exposing the internal steel wires and accelerating the corrosion process. To address the aforementioned issues, this patent proposes a novel flame-retardant and wear-resistant rope and its preparation method. By optimizing the rubber formulation, the comprehensive properties of the rubber material, such as flame retardancy, antistatic properties, and wear resistance, are improved. Summary of the Invention

[0004] To address the shortcomings of the existing technology, this invention provides a flame-retardant and wear-resistant rope, comprising a steel wire rope and a rubber sheath; the rubber sheath comprises an inner rubber layer and an outer rubber layer. The inner rubber layer is close to the surface of the steel wires in the steel wire rope, exhibiting strong adhesion; the outer rubber layer covers the outer perimeter of the rope and possesses excellent flame-retardant, wear-resistant, and antistatic properties.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] A flame-retardant and wear-resistant rope includes a steel wire rope and a rubber sheath; the rubber sheath includes an inner rubber layer and an outer rubber layer.

[0007] Preferably, the composition of the inner layer rubber comprises, by weight, the following components:

[0008] 80-150 parts styrene-butadiene rubber, 10-20 parts silica, 2-5 parts activator, 5-15 parts reinforcing agent, 0.5-2 parts antioxidant, 1-3 parts γ-mercaptopropyltriethoxysilane, 2-5 parts rubber adhesive, 2-5 parts cobalt neodecanoate, 1-2 parts sulfur, 1-2 parts vulcanization accelerator.

[0009] Preferably, the rubber adhesive is composed of rubber adhesive RA and rubber adhesive RE; the weight ratio of rubber adhesive RA and rubber adhesive RE is 1-2:1.

[0010] In the above-mentioned composition of the inner layer rubber, styrene-butadiene rubber serves as the matrix material. The rigid structure of styrene in its molecular chain and the flexible segments of butadiene work together to give the inner layer rubber basic elasticity and mechanical strength. Silica, through its high specific surface area and surface hydroxyl groups, forms physical entanglement and chemical bonding with rubber molecules, improving tear resistance and delaying crack propagation. Reinforcing agents enhance mechanical strength and hardness, improve dynamic fatigue performance, and maintain structural stability over a wide temperature range.

[0011] γ-Mercaptopropyltriethoxysilane, acting as a coupling agent, forms Zn-S covalent bonds between its mercapto groups and the zinc plating layer on the steel wire surface, while the siloxane groups crosslink with the rubber matrix, significantly enhancing interfacial adhesion and preventing peeling during long-term use. The Co ions from the dissociation of cobalt neodecanoate form Zn-O-Co coordination complexes with the zinc plating layer, simultaneously catalyzing the dehydrogenation reaction between the silane and zinc interfaces, thus improving bonding efficiency. The combination of rubber adhesives RA (methylene donor) and RE (methylene acceptor) constitutes the meta-methyl-white system, generating a three-dimensional phenolic resin network and forming a dense chelating layer. The synergistic effect of these three components solves the problem of long-term adhesion degradation.

[0012] Activators promote a uniform distribution of crosslinking density during vulcanization, avoiding early wear caused by local defects; vulcanization accelerators control the vulcanization rate through stepwise activation, ensuring that the rubber maintains a stable crosslinking structure over a wide temperature range; antioxidants inhibit oxidative chain reactions by capturing free radicals, extending the material's lifespan.

[0013] Preferably, the outer rubber component formulation, by weight, comprises the following components:

[0014] 50-80 parts styrene-butadiene rubber, 30-60 parts nitrile rubber, 10-30 parts flame retardant and wear-resistant reinforcing agent, 10-30 parts silica, 2-8 parts activator, 10-20 parts reinforcing agent, 1-2 parts antioxidant, 1-3 parts antistatic agent, 1-2 parts sulfur, 1-2 parts vulcanization accelerator.

[0015] Preferably, the antistatic agent is a complex composed of a quaternary ammonium salt cationic surfactant and a nonionic surfactant, with an amine value of 5-15 KOH mg / g and a quaternary ammonium salt content of 40-65%.

[0016] The antistatic agent is suitable for rubber matrix and can achieve efficient and long-lasting antistatic effect with low addition amount, and has good heat resistance.

[0017] Preferably, the antistatic agent is either HDC-305 or HDC-308.

[0018] In the aforementioned inner layer rubber formulation, a blend of styrene-butadiene rubber (SBR) and acrylonitrile-butadiene rubber (NBR) is used. The oil resistance and abrasion resistance of NBR compensate for the performance shortcomings of SBR under extreme working conditions. Silica, through its high specific surface area and surface hydroxyl groups, forms physical entanglement and chemical bonds with rubber molecules, improving tear resistance and delaying crack propagation. Reinforcing agents enhance mechanical strength and hardness, improve dynamic fatigue performance, and improve structural stability over a wide temperature range. Activators promote uniform distribution of crosslinking density during vulcanization, avoiding early wear caused by local defects. Vulcanization accelerators control the vulcanization rate through stepwise activation, ensuring that the rubber maintains a stable crosslinking structure over a wide temperature range and sustains dynamic mechanical properties. Antioxidants inhibit oxidative chain reactions by capturing free radicals, extending material life.

[0019] Preferably, the flame-retardant and wear-resistant reinforcing agent is prepared by the following method:

[0020] Ammonium polyphosphate, melamine cyanurate, and bis-[3-(triethoxysilyl)propyl]-tetrasulfide hydrolysate were mixed, heated and stirred, then carboxylated carbon nanotubes were added and stirred again. After drying, flame-retardant particles were obtained.

[0021] Nano-zirconia was dispersed in an aqueous ethanol solution, γ-aminopropyltriethoxysilane was added, stirred, filtered, and dried to obtain aminated zirconia; flame-retardant particles were dispersed in an aqueous ethanol solution, aminated zirconia, polyimide micro powder and γ-glycidoxypropyltrimethoxysilane were added, ball-milled, heated and stirred, and dried to obtain flame-retardant / wear-resistant composite particles.

[0022] Flame-retardant / wear-resistant composite particles were dispersed in carboxylated nitrile latex, and potassium persulfate and tetramethylethylenediamine were added sequentially. The mixture was heated to react and then dried to obtain a flame-retardant and wear-resistant reinforcing agent.

[0023] In the preparation of the flame retardant and wear-resistant reinforcing agent, flame retardant synergy is first achieved through the chemical bonding of silane bis-[3-(triethoxysilyl)propyl]-tetrasulfide hydrolysate with ammonium polyphosphate and melamine cyanurate. After the ethoxy group of silane is partially hydrolyzed to obtain silanol, it forms a Si-OP covalent bond with the phosphate group of ammonium polyphosphate. At the same time, it associates with the amino group of melamine cyanurate through hydrogen bonding to construct a three-dimensional network framework. The carboxyl group of carboxylated carbon nanotubes undergoes esterification with the ethoxy group of silane, so that it is uniformly interspersed in the flame retardant network framework to form a thermally / electrically conductive pathway, thus obtaining flame retardant particles.

[0024] Secondly, γ-aminopropyltriethoxysilane is hydrolyzed in an aqueous ethanol solution, and its silanol group condenses with the hydroxyl group on the surface of nano-zirconia to form Zr-O-Si bonds. The terminal primary amino group is exposed to obtain aminated zirconia. The amino group dehydrates and condenses with the silanol group on the surface of flame-retardant particles to form Si-ON bonds. At the same time, the epoxy group of γ-glycidyl etheroxypropyltrimethoxysilane reacts with the amino group under ball milling and thermal activation to generate secondary amine bonds -C-NH-CH2-CH(OH)-. The polyimide micro powder is anchored to the surface of zirconia through epoxy-amino crosslinking to form a core-shell wear-resistant unit, resulting in flame-retardant / wear-resistant composite particles.

[0025] Finally, under the initiation of the potassium persulfate / tetramethylethylenediamine redox system, the carboxyl acrylonitrile latex generates sulfate free radicals, which attack the latex double bonds to generate polymer free radicals. These free radicals then undergo graft copolymerization with the amino groups remaining on the surface of the flame-retardant / wear-resistant composite particles, thereby coating the composite particles with a reactive rubber layer to obtain a flame-retardant and wear-resistant reinforcing agent.

[0026] Compared with the direct addition of conventional flame retardants, the flame-retardant and wear-resistant reinforcing agent has better interfacial stability and significantly reduced high-temperature migration rate of flame-retardant particles. At the same time, the aminated zirconium oxide and flame-retardant particles are condensed through Si-ON bonds, and then the polyimide is anchored by secondary amine bonds through the ring-opening reaction of epoxy silane, which further improves the energy dispersion efficiency of abrasion compared with the direct use of zirconium oxide. The carboxyl nitrile latex free radical grafting forms a reactive coating layer, which enables the composite particles to form chemical bonds with the nitrile rubber matrix. Compared with direct physical mixing, its interfacial bonding energy is significantly improved, avoiding the performance degradation of rubber due to migration of flame retardants / wear-resistant fillers.

[0027] It is evident that the outer rubber formulation of this invention achieves a balance of flame retardant properties, wear resistance, and mechanical strength over a wide temperature range through the synergistic effect of adding flame retardant and wear-resistant reinforcing agents and other components, thus meeting the long-term service requirements of ropes under extreme working conditions.

[0028] Preferably, the flame-retardant and wear-resistant reinforcing agent is prepared by the following method:

[0029] By weight, 2-8 parts of ammonium polyphosphate, 0.5-4 parts of melamine cyanurate and 1-3 parts of bis-[3-(triethoxysilyl)propyl]-tetrasulfide hydrolysate are mixed, heated to 70-90℃ and stirred for 20-40 min, then 0.1-0.5 parts of carboxylated carbon nanotubes are added and stirring is continued for 10-30 min. After drying, flame-retardant particles are obtained.

[0030] Disperse 1-3 parts of nano-zirconia in 10-20 parts of 70-90wt% ethanol aqueous solution, add 0.1-0.5 parts of γ-aminopropyltriethoxysilane, stir at room temperature for 2-4 hours, filter, and dry to obtain aminated zirconia; disperse 2-8 parts of flame-retardant particles in 5-20 parts of 90-98wt% ethanol aqueous solution, add 1-3 parts of aminated zirconia, 0.5-1.5 parts of polyimide micro powder and 0.1-0.5 parts of γ-glycidyl etheroxypropyltrimethoxysilane, ball mill for 0.5-2 hours, then heat to 55-70℃ and stir for 1-3 hours, and dry to obtain flame-retardant / wear-resistant composite particles;

[0031] Disperse 2-8 parts of flame-retardant / wear-resistant composite particles in 1-5 parts of carboxylated nitrile latex, then add 0.01-0.03 parts of potassium persulfate and 0.005-0.015 parts of tetramethylethylenediamine in sequence, heat to 55-70℃ and react for 30-50 minutes, then dry to obtain a flame-retardant and wear-resistant reinforcing agent.

[0032] Preferably, the bis-[3-(triethoxysilyl)propyl]-tetrasulfide hydrolysate is prepared by mixing bis-[3-(triethoxysilyl)propyl]-tetrasulfide and 90-98wt% aqueous ethanol solution at a weight ratio of 1:8-10 and stirring at room temperature for 30-50 minutes.

[0033] Preferably, the carboxylated carbon nanotubes are carboxylated multi-walled carbon nanotubes.

[0034] The carboxylated multi-walled carbon nanotubes have a carboxyl content of 1.0-1.5 wt%, an outer diameter of 20-30 nm, an inner diameter of 5-10 nm, a length of 10-30 μm, and a purity of >95%.

[0035] Preferably, the particle size of the nano-zirconia is 30-60 nm.

[0036] Preferably, the solid content of the carboxylated nitrile latex is 40-50%.

[0037] Preferably, the particle size D90 of the polyimide micro powder is ≤45μm.

[0038] Preferably, the ball milling speed is 500-800 rpm, the ball milling media are zirconia grinding balls with a diameter of 1-3 mm, and the ball-to-material ratio is 8-15:1.

[0039] Preferably, the stirring speed is 100-300 rpm.

[0040] Preferably, the activator is composed of zinc oxide and stearic acid; the weight ratio of the activated zinc oxide to stearic acid is 1:0.1-0.5.

[0041] Preferably, the reinforcing agent is at least one of N550 carbon black, N774 carbon black, N660 carbon black, N339 carbon black, and N220 carbon black.

[0042] Preferably, the reinforcing agent is composed of N550 carbon black and N774 carbon black in a weight ratio of 1:0.5-2.

[0043] Preferably, the antioxidant is at least one of antioxidant RD, antioxidant DNP, and antioxidant 6PPD.

[0044] Preferably, the antioxidant is antioxidant RD.

[0045] Preferably, the vulcanization accelerator is at least one of N,N-dicyclohexyl-2-benzothiazole sulfenamide, zinc diethyl dithiocarbamate, and 2-mercaptobenzothiazole.

[0046] Preferably, the vulcanization accelerator is composed of N,N-dicyclohexyl-2-benzothiazole sulfenamide and zinc diethyldithiocarbamate in a weight ratio of 1:0.1-0.5.

[0047] A flame-retardant and abrasion-resistant rope includes a steel wire rope and a rubber sheath; the rope is made by vulcanizing the steel wire rope along the length of the rope within the rubber sheath.

[0048] Preferably, the rubber sheath comprises an inner rubber layer and an outer rubber layer; wherein the inner rubber layer accounts for 10±2wt% of the rubber sheath; the inner rubber layer is close to the surface of the steel wire of the wire rope and has a strong adhesion to the steel wire; the outer rubber layer covers the outer periphery of the rope and has excellent flame retardant, wear-resistant and antistatic properties.

[0049] Preferably, the adhesive strength between the inner rubber layer and the steel wire (galvanized) is >135kN / m, as determined by the method in standard GB / T 5755-2021.

[0050] Preferably, the wire rope is a round strand wire rope with a metal core that is twisted in a crisscross pattern.

[0051] Preferably, the wire rope is a tension-free wire rope, the wires of the wire rope are B-grade galvanized, and the wire rope is degreased.

[0052] Preferably, the rope has a flat cross-section.

[0053] Preferably, the width and thickness of the rope depend on the number of wire ropes, the diameter, and the required specific gravity of the rope (mass per meter of rope).

[0054] Preferably, the nominal width of the rope is 30-250mm, including but not limited to: 30mm, 38.5mm, 41mm, 52mm, 72mm, 78mm, 82mm, 92mm, 93mm, 98mm, 100mm, 103mm, 105mm, 110mm, 112mm, 118mm, 130mm, 140mm, 145mm, 148mm, 150mm, 153mm, 154mm, 162mm, 174mm, 176mm, 180mm, 188mm, 190mm, 192mm, 196mm, 198mm, 200mm, 202mm, 206mm, and 212mm.

[0055] Preferably, the nominal thickness of the rope is 10-40mm, including but not limited to: 10mm, 20mm, 26mm, 28mm, 29mm, 30mm, 33mm, 35mm, 37mm, 38mm, and 40mm.

[0056] Preferably, the number of steel wire ropes in the rope is an even number, including but not limited to: 2, 4, 6, 8, 10 or 12.

[0057] Preferably, the nominal diameter of the steel wire rope in the rope is 4-30mm, including but not limited to:

[0058] 4.2mm, 8.25mm, 16.5mm, 18.0mm or 27.0mm.

[0059] Preferably, the nominal weight of each meter of rope is 0.5-25 kg / m, including but not limited to: 0.5 kg / m, 0.6 kg / m, 0.75 kg / m, 1.0 kg / m, 1.25 kg / m, 1.5 kg / m, 1.75 kg / m, 2.0 kg / m, 4.75 kg / m, 6.5 kg / m, 7.0 kg / m, 8.5 kg / m, 8.8 kg / m, 9.2 kg / m, 10 kg / m. 5kg / m, 12.0kg / m, 12.5kg / m, 13.0kg / m, 13.5kg / m, 14.0kg / m, 14.4kg / m, 15.0kg / m, 15.5kg / m, 15.6kg / m, 15.75kg / m, 16.2kg / m, 16.5kg / m, 16.8kg / m, 17.5kg / m, 17.6kg / m, 25.0kg / m.

[0060] Preferably, the spacing between the steel wires in the rope is 3-40mm, including but not limited to: 3mm, 4mm, 5mm, 5.2mm, 5.4mm, 6mm, 6.5mm, 6.8mm, 7mm, 8mm, 9mm, 11mm, 13mm, 14mm, 14.4mm, 16mm, 18mm, 20mm, 24mm, and 40mm.

[0061] Preferably, the distance from the edge of the steel wire rope to the edge of the rubber in the rope is 2-11mm, including but not limited to: 2.9mm, 4.75mm, 5.75mm, 5.88mm, 6mm, 6.25mm, 6.5mm, 6.75mm, 7.5mm, 8.25mm, 8.5mm, 9.25mm, 10mm, 10.0mm, 10.25mm, 10.5mm, 10.75mm, and 10.8mm.

[0062] This invention also provides a method for preparing the above-mentioned flame-retardant and wear-resistant rope, comprising the following steps:

[0063] Based on the rope design, determine the position and number of wire ropes in the rope cross-section;

[0064] The steel wire ropes are alternately placed in a crisscross pattern, and after passing through the entire machine and device system, the steel wire ropes are fixed, with all steel wire ropes subjected to the same tension; preferably, the tension is ≥5kN; on the vulcanizing press, the surface of each steel wire rope is first coated with an inner layer of rubber calendering mixture, and then all steel wire ropes are coated with an outer layer of rubber calendering mixture, and then pressed. After pressing, they are moved to the vulcanizing press for vulcanization. Preferably, the vulcanization temperature is 150±15℃, the pressure is 5±1.5MPa, and the time is set according to the rope size; preferably, the time is ≥40min; after completion, if the inspection is qualified, the rope is wound and rolled up to obtain a finished rope with the inner / outer rubber interface fused.

[0065] The beneficial effects of this invention are:

[0066] This invention provides a flame-retardant and wear-resistant rope with a flat cross-section, made by vulcanizing steel wire rope along its length within a rubber sheath. The rubber sheath comprises an inner rubber layer and an outer rubber layer. The inner rubber layer is adjacent to the surface of the steel wires in the rope, exhibiting strong adhesion. The outer rubber layer covers the outer perimeter of the rope and possesses excellent flame-retardant, wear-resistant, and antistatic properties. This invention overcomes the problems of insufficient adhesion and poor wear resistance found in existing ropes, making it less prone to wear or peeling during long-term use and preventing corrosion of the internal steel wires due to exposure. The rope can operate in ambient temperatures ranging from -25℃ to +60℃ and can be used in hoisting devices and vertical shafts in coal mines and mine shafts, including mines with hazardous gases and / or dust, salt mines, and other mining areas, for lifting and hoisting minerals, personnel, materials, and equipment. This invention also provides a simple and easily applicable method for preparing the aforementioned flame-retardant and wear-resistant rope. Attached Figure Description

[0067] Figure 1 This is the cross-section of the rope. 1-Inner rubber layer; 2-Outer rubber layer; 3-Round strand steel wire rope, formed by a metal core wound in a crisscross pattern. Detailed Implementation

[0068] The technical solutions of the present invention will be clearly and completely described below with reference to specific embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0069] Some of the raw materials used in the examples are described below:

[0070] Styrene-butadiene rubber, model: SBR1502, Qilu Petrochemical, manufacturer: China National Petroleum Corporation.

[0071] Nitrile rubber, model: NBR3305E, Lanzhou Petrochemical, manufacturer: China National Petroleum Corporation.

[0072] Silica, fumed silica, model: ZB-8150, manufacturer: Jinan Zhongbei Fine Chemical Co., Ltd.

[0073] Rubber adhesive RA and rubber adhesive RE, manufacturer: Jiangsu Guoli Chemical Technology Co., Ltd.

[0074] Antistatic agent, model: HDC-305, manufacturer: Hangzhou Lin'an Dechang Static Electricity Technology Co., Ltd.

[0075] Carboxylated multi-walled carbon nanotubes, outer diameter: 20-30nm, inner diameter: 5-10nm, length: 10-30μm, carboxyl content: 1.23wt%, purity: >95%, manufacturer: Zhongke Leiming (Beijing) Technology Co., Ltd.

[0076] Nano-zirconia, model: M560, primary particle size: 30nm, manufacturer: Nanjing Tianxing New Materials Co., Ltd.

[0077] Polyimide micro powder, model: Toughimid-4602, particle size D90: ≤45μm, manufacturer: Suzhou Yuxin Tiancai New Material Application Technology Co., Ltd.

[0078] Carboxylated acrylonitrile latex, solid content: 44±1%, surface tension: 50±5mN / m, manufacturer: Jiangsu Yatai Chemical Co., Ltd.

[0079] Example 1

[0080] A flame-retardant and abrasion-resistant rope includes a steel wire rope and a rubber sheath; the rope is made by vulcanizing the steel wire rope along the length of the rope within the rubber sheath.

[0081] The rubber sheath comprises an inner rubber layer and an outer rubber layer; wherein, the inner rubber layer is close to the surface of the steel wire of the wire rope and has a strong adhesion to the steel wire; the outer rubber layer covers the outside of the rope and has excellent flame retardant, wear-resistant and antistatic properties; the inner rubber layer accounts for 10±2wt% of the rubber sheath.

[0082] The wire rope is a round strand wire rope with a metal core that is twisted in a crisscross pattern.

[0083] The wire rope used is a tension-free wire rope, the wires of the wire rope are grade B galvanized, and the wire rope is degreased.

[0084] The rope has a flat cross-section.

[0085] The width and thickness of the rope depend on the number of wire ropes, the diameter, and the required specific gravity of the rope (mass per meter of rope); the nominal width of the rope is 30-250mm and the nominal thickness is 10-40mm.

[0086] For example, the nominal width of the rope is 82mm and the nominal thickness is 10mm. The rope contains 8 steel wires with a nominal diameter of 4.2mm and a nominal weight of 1.5kg / m. The spacing between the steel wires is 5mm, and the distance from the edge of the steel wire to the edge of the rubber is 2.9mm.

[0087] A method for preparing a flame-retardant and abrasion-resistant rope includes the following steps:

[0088] Based on the rope design, determine the position and number of wire ropes in the rope cross-section;

[0089] The steel wire ropes are alternately placed in a crisscross pattern, and after passing through the entire machine and device system, the steel wire ropes are fixed. All steel wire ropes are subjected to the same tension (≥5kN). On the vulcanizing press, the surface of each steel wire rope is first coated with an inner layer of rubber calendering mixture, and then all steel wire ropes are coated with an outer layer of rubber calendering mixture. After pressing, the ropes are moved to the vulcanizing press for vulcanization. The vulcanization temperature is 150±15℃, the pressure is 5±1.5MPa, and the time is set according to the rope size (≥40min). After completion, the ropes are inspected and qualified, and then wound up to obtain a finished rope with the inner and outer rubber interfaces fused.

[0090] Example 2

[0091] The composition of the inner layer rubber, by weight, includes the following components:

[0092] 100 parts styrene-butadiene rubber, 15 parts silica, 3.5 parts activator, 10 parts reinforcing agent, 1 part antioxidant RD, 2 parts γ-mercaptopropyltriethoxysilane, 3 parts rubber adhesive, 3.5 parts cobalt neodecanoate, 1.8 parts sulfur, and 1.2 parts vulcanization accelerator.

[0093] The reinforcing agent is composed of N550 carbon black and N774 carbon black in a weight ratio of 1:1. The activator is composed of zinc oxide and stearic acid in a weight ratio of 1:0.3. The vulcanization accelerator is composed of N,N-dicyclohexyl-2-benzothiazole sulfenamide and zinc diethyldithiocarbamate in a weight ratio of 1:0.35. The rubber adhesive is composed of rubber adhesive RA and rubber adhesive RE in a weight ratio of 1.2:1.

[0094] The bonding strength of the steel wire rope was determined according to the method in standard GB / T 5755-2021 (steel wire embedment depth 50mm, pull-out speed 100mm / min); the bonding strength between the inner rubber layer and the steel wire (galvanized) described in Example 2 was 137.5kN / m.

[0095] Comparative Example 1

[0096] The difference between the composition of the inner layer rubber and that of Example 2 is that γ-mercaptopropyltriethoxysilane is not added; and by weight, it specifically includes the following components:

[0097] 100 parts styrene-butadiene rubber, 15 parts silica, 3.5 parts activator, 10 parts reinforcing agent, 1 part antioxidant RD, 3 parts rubber adhesive, 3.5 parts cobalt neodecanoate, 1.8 parts sulfur, and 1.2 parts vulcanization accelerator.

[0098] The reinforcing agent is composed of N550 carbon black and N774 carbon black in a weight ratio of 1:1. The activator is composed of zinc oxide and stearic acid in a weight ratio of 1:0.3. The vulcanization accelerator is composed of N,N-dicyclohexyl-2-benzothiazole sulfenamide and zinc diethyldithiocarbamate in a weight ratio of 1:0.35. The rubber adhesive is composed of rubber adhesive RA and rubber adhesive RE in a weight ratio of 1.2:1.

[0099] The bonding strength of the steel wire rope was determined according to the method in standard GB / T 5755-2021 (steel wire embedment depth 50mm, pull-out speed 100mm / min); the bonding strength between the inner rubber layer and the steel wire (galvanized) in Comparative Example 1 was 120.2kN / m.

[0100] Comparative Example 2

[0101] The difference between the composition of the inner layer rubber and that of Example 2 is that no rubber adhesive was added; and by weight, it specifically includes the following components:

[0102] 100 parts styrene-butadiene rubber, 15 parts silica, 3.5 parts activator, 10 parts reinforcing agent, 1 part antioxidant RD, 2 parts γ-mercaptopropyltriethoxysilane, 3.5 parts cobalt neodecanoate, 1.8 parts sulfur, and 1.2 parts vulcanization accelerator.

[0103] The reinforcing agent is composed of N550 carbon black and N774 carbon black in a weight ratio of 1:1. The activator is composed of zinc oxide and stearic acid in a weight ratio of 1:0.3. The vulcanization accelerator is composed of N,N-dicyclohexyl-2-benzothiazole sulfenamide and zinc diethyldithiocarbamate in a weight ratio of 1:0.35.

[0104] The bonding strength of the steel wire rope was determined according to the method in standard GB / T 5755-2021 (steel wire embedment depth 50mm, pull-out speed 100mm / min); the bonding strength between the inner rubber layer and the steel wire (galvanized) in Comparative Example 2 was 98.8kN / m.

[0105] Comparative Example 3

[0106] The difference between the composition of the inner layer rubber and that of Example 2 is that cobalt neodecanoate is not added; and by weight, it specifically includes the following components:

[0107] 100 parts styrene-butadiene rubber, 15 parts silica, 3.5 parts activator, 10 parts reinforcing agent, 1 part antioxidant RD, 2 parts γ-mercaptopropyltriethoxysilane, 3 parts rubber adhesive, 1.8 parts sulfur, and 1.2 parts vulcanization accelerator.

[0108] The reinforcing agent is composed of N550 carbon black and N774 carbon black in a weight ratio of 1:1. The activator is composed of zinc oxide and stearic acid in a weight ratio of 1:0.3. The vulcanization accelerator is composed of N,N-dicyclohexyl-2-benzothiazole sulfenamide and zinc diethyldithiocarbamate in a weight ratio of 1:0.35. The rubber adhesive is composed of rubber adhesive RA and rubber adhesive RE in a weight ratio of 1.2:1.

[0109] The bonding strength of the steel wire rope was determined according to the method in standard GB / T 5755-2021 (steel wire embedment depth 50mm, pull-out speed 100mm / min); the bonding strength between the inner rubber layer and the steel wire (galvanized) in Comparative Example 3 was 109.6kN / m.

[0110] Compared to Comparative Examples 1-3, the inner rubber layer of Example 2, which simultaneously incorporates γ-mercaptopropyltriethoxysilane, a rubber adhesive, and cobalt neodecanoate, exhibits significantly higher adhesion strength to the steel wire (galvanized) than Comparative Examples 1-3. This is because γ-mercaptopropyltriethoxysilane acts as a coupling agent, with its thiol groups forming Zn-S covalent bonds with the zinc plating layer on the steel wire surface, while the siloxane groups crosslink with the rubber matrix, greatly enhancing interfacial adhesion. The Co ions dissociated from cobalt neodecanoate form Zn-O-Co coordination complexes with the zinc plating layer, simultaneously catalyzing the dehydrogenation reaction between the silane and zinc interfaces, thus improving bonding efficiency. The combination of the rubber adhesive RA (methylene donor) and the rubber adhesive RE (methylene acceptor) constitutes a meta-methyl-white system, generating a three-dimensional phenolic resin network and forming a dense chelating layer. The combined effects of these three components further enhance the adhesion between the inner rubber layer and the steel wire rope surface.

[0111] Example 3

[0112] The outer rubber component formulation, by weight, comprises the following components:

[0113] 60 parts styrene-butadiene rubber, 40 parts nitrile rubber, 25 parts flame retardant and abrasion resistant reinforcing agent, 20 parts silica, 5 parts activator, 15 parts reinforcing agent, 1.5 parts antioxidant RD, 2 parts antistatic agent, 1.8 parts sulfur, and 1.2 parts vulcanization accelerator.

[0114] The reinforcing agent is composed of N550 carbon black and N774 carbon black in a weight ratio of 1:1. The activator is composed of zinc oxide and stearic acid in a weight ratio of 1:0.3. The vulcanization accelerator is composed of N,N-dicyclohexyl-2-benzothiazole sulfenamide and zinc diethyldithiocarbamate in a weight ratio of 1:0.35.

[0115] The flame-retardant and wear-resistant reinforcing agent is prepared by the following method:

[0116] By weight, 5 parts of ammonium polyphosphate, 1.5 parts of melamine cyanurate and 1.5 parts of bis-[3-(triethoxysilyl)propyl]-tetrasulfide hydrolysate were mixed, heated to 80°C and stirred for 30 min, then 0.2 parts of carboxylated multi-walled carbon nanotubes were added and stirred for another 20 min. After drying, flame-retardant particles were obtained.

[0117] Two parts of nano-zirconia were dispersed in 15 parts of 80wt% ethanol aqueous solution, and 0.2 parts of γ-aminopropyltriethoxysilane were added. The mixture was stirred at room temperature for 3 hours, filtered, and dried to obtain aminated zirconia. Five parts of flame-retardant particles were dispersed in 10 parts of 95wt% ethanol aqueous solution, and 2 parts of aminated zirconia, 0.8 parts of polyimide micro powder, and 0.2 parts of γ-glycidyl etheroxypropyltrimethoxysilane were added. The mixture was ball-milled for 1 hour, then heated to 60℃ and stirred for 1.5 hours. The mixture was dried to obtain flame-retardant / wear-resistant composite particles.

[0118] Five parts of flame-retardant / wear-resistant composite particles were dispersed in 2.5 parts of carboxylated nitrile latex, and 0.02 parts of potassium persulfate and 0.01 parts of tetramethylethylenediamine were added sequentially. The mixture was heated to 60°C and reacted for 40 minutes, then dried to obtain a flame-retardant and wear-resistant reinforcing agent. The bis-[3-(triethoxysilyl)propyl]-tetrasulfide hydrolysate was prepared by mixing bis-[3-(triethoxysilyl)propyl]-tetrasulfide and 95wt% ethanol aqueous solution at a weight ratio of 1:9 and stirring at room temperature for 40 minutes. The ball milling speed was 600 rpm, the milling media were 1 mm diameter zirconia grinding balls, the ball-to-material ratio was 10:1, and the stirring speed was 200 rpm.

[0119] Abrasion resistance was determined by the method in standard GB / T 1689-2014, with the wear volume measured in mm. 3 Flame retardancy was determined according to the method in UL94-2023; antistatic properties were determined according to the method in ISO 284:2012, with surface resistivity measured in Ω; the wear volume of the outer rubber layer described in Example 5 was 46 mm². 3 It has a flame retardant rating of V0 and a surface resistivity of 3.5 × 10⁻⁶. 6 Ω.

[0120] Comparative Example 4

[0121] The difference between the outer rubber layer and that in Example 3 is that the preparation method of the flame-retardant and wear-resistant reinforcing agent is different; specifically:

[0122] By weight, 5 parts of ammonium polyphosphate, 1.5 parts of melamine cyanurate and 1.5 parts of bis-[3-(triethoxysilyl)propyl]-tetrasulfide hydrolysate were mixed, heated to 80°C and stirred for 30 min, then 0.2 parts of carboxylated multi-walled carbon nanotubes were added and stirred for another 20 min. After drying, flame-retardant particles were obtained.

[0123] Two parts of nano-zirconia were dispersed in 15 parts of 80wt% ethanol aqueous solution, and 0.2 parts of γ-aminopropyltriethoxysilane were added. The mixture was stirred at room temperature for 3 hours, filtered, and dried to obtain aminated zirconia. Five parts of flame-retardant particles were dispersed in 10 parts of 95wt% ethanol aqueous solution, and 2 parts of aminated zirconia, 0.8 parts of polyimide micro powder, and 0.2 parts of γ-glycidyl etheroxypropyltrimethoxysilane were added. The mixture was ball-milled for 1 hour, then heated to 60℃ and stirred for 1.5 hours. The mixture was then dried to obtain a flame-retardant and wear-resistant reinforcing agent.

[0124] The bis-[3-(triethoxysilyl)propyl]-tetrasulfide hydrolysate is prepared by mixing bis-[3-(triethoxysilyl)propyl]-tetrasulfide and 95wt% ethanol aqueous solution at a weight ratio of 1:9 and stirring at room temperature for 40 minutes; the ball milling speed is 600 rpm, the ball milling media is 1 mm diameter zirconia grinding balls, the ball-to-material ratio is 10:1, and the stirring speed is 200 rpm.

[0125] Abrasion resistance was determined by the method in standard GB / T 1689-2014, with the wear volume measured in mm. 3 Flame retardancy was determined according to the method in UL94-2023 standard; the abrasion volume of the outer rubber layer described in Comparative Example 4 was 58 mm. 3 The flame retardant rating is V1.

[0126] Comparative Example 5

[0127] The difference between the outer rubber layer and that in Example 3 is that the preparation method of the flame-retardant and wear-resistant reinforcing agent is different; specifically:

[0128] By weight, 5 parts ammonium polyphosphate, 1.5 parts melamine cyanurate and 0.2 parts carboxylated multi-walled carbon nanotubes are mixed evenly to obtain a flame-retardant mixture;

[0129] Two parts of nano-zirconia were dispersed in 15 parts of 80wt% ethanol aqueous solution, and 0.2 parts of γ-aminopropyltriethoxysilane were added. The mixture was stirred at room temperature for 3 hours, filtered, and dried to obtain aminated zirconia. Five parts of flame retardant mixture were dispersed in 10 parts of 95wt% ethanol aqueous solution, and 2 parts of aminated zirconia, 0.8 parts of polyimide micro powder, and 0.2 parts of γ-glycidyl etheroxypropyltrimethoxysilane were added. The mixture was ball-milled for 1 hour, then heated to 60℃ and stirred for 1.5 hours. The mixture was dried to obtain flame retardant / wear-resistant composite particles.

[0130] Five parts of flame-retardant / wear-resistant composite particles were dispersed in 2.5 parts of carboxylated nitrile latex. Then, 0.02 parts of potassium persulfate and 0.01 parts of tetramethylethylenediamine were added sequentially. The mixture was heated to 60℃ and reacted for 40 minutes, followed by drying to obtain the flame-retardant and wear-resistant reinforcing agent. The ball milling speed was 600 rpm, the milling media were 1 mm diameter zirconia grinding balls, the ball-to-material ratio was 10:1, and the stirring speed was 200 rpm.

[0131] Abrasion resistance was determined by the method in standard GB / T 1689-2014, with the wear volume measured in mm. 3 Flame retardancy was determined according to the method in UL94-2023 standard; the abrasion volume of the outer rubber layer described in Comparative Example 5 was 63 mm. 3 It has a flame retardant rating of V2.

[0132] Comparative Example 6

[0133] The difference between the outer rubber layer and that in Example 3 is that the preparation method of the flame-retardant and wear-resistant reinforcing agent is different; specifically:

[0134] By weight, 5 parts of ammonium polyphosphate, 1.5 parts of melamine cyanurate and 1.5 parts of bis-[3-(triethoxysilyl)propyl]-tetrasulfide hydrolysate were mixed, heated to 80°C and stirred for 30 min, then 0.2 parts of carboxylated multi-walled carbon nanotubes were added and stirred for another 20 min. After drying, flame-retardant particles were obtained.

[0135] Five parts of flame-retardant particles were dispersed in 10 parts of 95wt% ethanol aqueous solution, and two parts of nano-zirconia and 0.8 parts of polyimide micro powder were added and ball-milled for 1 hour. Then the mixture was heated to 60℃ and stirred for 1.5 hours and dried to obtain a flame-retardant / wear-resistant mixture.

[0136] Five parts of a flame-retardant / wear-resistant mixture were dispersed in 2.5 parts of carboxylated nitrile latex. Then, 0.02 parts of potassium persulfate and 0.01 parts of tetramethylethylenediamine were added sequentially. The mixture was heated to 60°C and reacted for 40 minutes, followed by drying to obtain a flame-retardant and wear-resistant reinforcing agent. The bis-[3-(triethoxysilyl)propyl]-tetrasulfide hydrolysate was prepared by mixing bis-[3-(triethoxysilyl)propyl]-tetrasulfide and a 95wt% ethanol aqueous solution at a weight ratio of 1:9 and stirring at room temperature for 40 minutes. The ball milling speed was 600 rpm, the milling media were 1 mm diameter zirconia grinding balls, the ball-to-material ratio was 10:1, and the stirring speed was 200 rpm.

[0137] Abrasion resistance was determined by the method in standard GB / T 1689-2014, with the wear volume measured in mm. 3 Flame retardancy was determined according to the method in standard UL94-2023; the abrasion volume of the outer rubber layer described in Comparative Example 6 was 71 mm². 3 The flame retardant rating is V1.

[0138] Compared to Comparative Examples 4-6, the flame-retardant and wear-resistant reinforcing agent in the outer rubber layer of Example 3, prepared using a specific process, exhibits significantly higher flame-retardant and wear-resistant properties. This is because, during the preparation of the flame-retardant and wear-resistant reinforcing agent, Comparative Example 4 did not coat the composite particles with a reactive rubber layer, Comparative Example 5 simply mixed ammonium polyphosphate, melamine cyanurate, and carboxylated multi-walled carbon nanotubes as flame-retardant components, and Comparative Example 6 directly ball-milled and stirred nano-zirconia and polyimide micropowder with flame-retardant particles. In contrast, the flame-retardant and wear-resistant reinforcing agent prepared using the specific process in Example 3 has better interfacial stability, higher abrasion energy dispersion efficiency, and forms chemical bonds with the rubber matrix, resulting in stronger interfacial bonding. This effectively prevents the performance degradation of the rubber due to the migration of the flame retardant / wear-resistant filler.

[0139] The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A flame-retardant and wear-resistant rope, characterized in that, Includes a steel wire rope and a rubber sheath; the rubber sheath includes an inner rubber layer and an outer rubber layer; The outer rubber component formulation, by weight, includes: 50-80 parts styrene-butadiene rubber, 30-60 parts nitrile rubber, 10-30 parts flame retardant and abrasion-resistant reinforcing agent, 10-30 parts silica, 2-8 parts activator, 10-20 parts reinforcing agent, 1-2 parts antioxidant, 1-3 parts antistatic agent, 1-2 parts sulfur, and 1-2 parts vulcanization accelerator; the preparation method of the flame retardant and abrasion-resistant reinforcing agent is as follows: Ammonium polyphosphate, melamine cyanurate, and bis-[3-(triethoxysilyl)propyl]-tetrasulfide hydrolysate were mixed, heated and stirred, carboxylated carbon nanotubes were added and stirred, and then dried to obtain flame-retardant particles. Nano-zirconia was dispersed in an aqueous ethanol solution, γ-aminopropyltriethoxysilane was added and stirred, filtered, and dried to obtain aminated zirconia; flame-retardant particles were dispersed in an aqueous ethanol solution, aminated zirconia, polyimide micro powder and γ-glycidoxypropyltrimethoxysilane were added, ball-milled, heated and stirred, and dried to obtain flame-retardant / wear-resistant composite particles. Flame-retardant / wear-resistant composite particles are dispersed in carboxylated nitrile latex, potassium persulfate and tetramethylethylenediamine are added, the mixture is heated to react, and then dried to obtain the final product. The composition of the inner layer rubber, by weight, includes: 80-150 parts styrene-butadiene rubber, 10-20 parts silica, 2-5 parts activator, 5-15 parts reinforcing agent, 0.5-2 parts antioxidant, 1-3 parts γ-mercaptopropyltriethoxysilane, 2-5 parts rubber adhesive, 2-5 parts cobalt neodecanoate, 1-2 parts sulfur, and 1-2 parts vulcanization accelerator; the rubber adhesive is composed of rubber adhesive RA and rubber adhesive RE.

2. The flame-retardant and wear-resistant rope according to claim 1, characterized in that, The antistatic agent is a complex composed of a quaternary ammonium salt cationic surfactant and a nonionic surfactant.

3. The flame-retardant and wear-resistant rope according to claim 1, characterized in that, The activator consists of zinc oxide and stearic acid.

4. The flame-retardant and wear-resistant rope according to claim 1, characterized in that, The reinforcing agent is at least one of N550 carbon black, N774 carbon black, N660 carbon black, N339 carbon black, and N220 carbon black; the antioxidant is at least one of antioxidant RD, antioxidant DNP, and antioxidant 6PPD; and the vulcanization accelerator is at least one of N,N-dicyclohexyl-2-benzothiazole sulfenamide, zinc diethyldithiocarbamate, and 2-mercaptobenzothiazole.

5. The flame-retardant and wear-resistant rope according to claim 1, characterized in that, The rope has a flat cross-section; the rope width is 30-250mm; and the rope thickness is 10-40mm.

6. The flame-retardant and wear-resistant rope according to claim 1, characterized in that, The number of steel wire ropes in the rope is an even number; the diameter of the steel wire ropes in the rope is 4-30mm; the mass of each meter of rope is 0.5-25kg / m.

7. The method for preparing the flame-retardant and abrasion-resistant rope according to any one of claims 1-6, characterized in that, Includes the following steps: Based on the rope design, determine the position and number of wire ropes in the rope cross-section; Place the steel wire ropes alternately on the left and right sides, fix the steel wire ropes, and apply the same tension; on the vulcanizing press, first cover the surface of each steel wire rope with the inner layer of rubber mixture, then cover all the steel wire ropes with the outer layer of rubber mixture, and press them. After pressing, move them to the vulcanizing press for vulcanization; after completion, if they pass the inspection, wind and roll them up to obtain the product.

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