Wear-resistant fireproof composite high-pressure pipe

Abstract

The utility model provides a kind of wear-resistant fireproof composite high-pressure pipe, belong to composite high-pressure pipe technical field, this wear-resistant fireproof composite high-pressure pipe includes pipe body, inner lining, outer protective layer and intermediate reinforcing layer;The pipe body is cylindrical structure, the inner lining is attached and is set in the inner circumferential surface of pipe body, the material of inner lining is high-temperature ceramic fibre composite material;The intermediate reinforcing layer is tightly covered in the outer circumferential surface of pipe body, and the intermediate reinforcing layer is made of the aramid fibre layer of multilayer braided structure;The outer protective layer is coated in the outer surface of intermediate reinforcing layer, and the material of outer protective layer is flame-retardant rubber material;The ratio of the radial thickness of inner lining and the wall thickness of pipe body is 1:3~1:5;It can solve the problem that the high-pressure pipe in the prior art cannot consider wear resistance, fireproof and pressure-bearing capacity when facing high temperature, high pressure and wear condition at the same time, which leads to the problems such as easy inner wall wear of pipeline, high-temperature softening, insufficient fireproof performance or decreased pressure-bearing capacity.

Description

Technical Field

[0001] This utility model belongs to the field of composite high-pressure pipe technology, specifically, it relates to a wear-resistant and fireproof composite high-pressure pipe. Background Technology

[0002] In modern industrial production, high-pressure pipes, as key components for fluid transportation, are widely used in numerous fields such as petrochemicals, natural gas transportation, hydraulic systems, fire-fighting water supply, and aerospace. With the development of industrial technology, the operating environment of high-pressure pipes is becoming increasingly complex, often requiring them to withstand multiple challenges simultaneously, including high temperature, high pressure, and media abrasion. Traditional high-pressure pipes are typically manufactured from a single material, such as steel or rubber. While steel pipes have high pressure resistance, they are prone to thermal softening at high temperatures, leading to a decrease in strength. Furthermore, the surface of steel pipes is easily abraded when transporting media containing particles, and their fire resistance is poor. Rubber hoses, while possessing a certain degree of flexibility and sealing, have limited pressure resistance and are prone to bulging, deformation, or even bursting under high pressure. Additionally, ordinary rubber materials lack sufficient high-temperature resistance and fire resistance. In recent years, some composite high-pressure pipes have begun to emerge. Existing technologies, such as covering the outer layer of rubber hoses with a steel wire braid or spraying an anti-corrosion layer on the inner wall of steel pipes, have improved certain performance aspects of high-pressure pipes to some extent, but still have significant shortcomings. While the steel wire layer in steel wire braided rubber hoses increases pressure resistance, the bonding strength between the steel wire and rubber is limited, making it prone to delamination under repeated pressure fluctuations, and the steel wire layer offers limited improvement in fire resistance. Although steel pipes with an inner anti-corrosion layer improve corrosion resistance, the anti-corrosion coating is usually thin and has poor wear resistance, making it easy to wear off when transporting media containing solid particles, thus losing its protective function. These existing technologies have failed to systematically address the multiple performance requirements of high-pressure pipes under complex operating conditions from the perspectives of structural design and material selection, leading to frequent failures in high-pressure pipes during actual use, increasing maintenance costs and posing serious safety hazards. Utility Model Content

[0003] In view of this, the present invention provides a wear-resistant and fire-resistant composite high-pressure pipe, which can solve the problems of existing high-pressure pipes when facing high temperature, high pressure and wear conditions at the same time. Due to the inability of a single material or simple composite structure to take into account wear resistance, fire resistance and pressure bearing capacity, the pipe is prone to inner wall wear, high temperature softening, insufficient fire resistance or reduced pressure bearing capacity during use.

[0004] This utility model is implemented as follows:

[0005] This utility model provides a wear-resistant and fire-resistant composite high-pressure pipe, comprising a pipe body, an inner lining layer, an outer protective layer, and an intermediate reinforcing layer; the pipe body is a cylindrical structure, the inner lining layer is fitted onto the inner circumferential surface of the pipe body, and the material of the inner lining layer is a high-temperature resistant ceramic fiber composite material; the intermediate reinforcing layer is tightly wrapped around the outer circumferential surface of the pipe body, and the intermediate reinforcing layer is composed of a multi-layer woven aramid fiber layer; the outer protective layer is wrapped around the outer surface of the intermediate reinforcing layer, and the material of the outer protective layer is a flame-retardant rubber material; the ratio of the radial thickness of the inner lining layer to the wall thickness of the pipe body is 1:3 to 1:5, the weaving angle of each layer of aramid fiber in the intermediate reinforcing layer is distributed in an alternating spiral pattern relative to the axial direction of the pipe body, the outer protective layer and the intermediate reinforcing layer are fixedly connected by vulcanization bonding, and flange joints are respectively provided at both ends of the pipe body, the inner circumferential surface of the flange joint is flush with the inner circumferential surface of the pipe body.

[0006] The technical advantages of the wear-resistant and fire-resistant composite high-pressure pipe provided by this utility model are as follows: By combining the inner lining, pipe body, intermediate reinforcing layer, and outer protective layer according to a specific structural relationship, the high-pressure pipe simultaneously possesses comprehensive properties of wear resistance, fire resistance, and high pressure resistance; the inner lining is made of high-temperature resistant ceramic fiber composite material bonded to the inner surface of the pipe body, effectively isolating the pipe body from direct corrosion by high-temperature media; the intermediate reinforcing layer is made of multi-layer aramid fiber braided structure tightly covering the outer surface of the pipe body, providing strong radial and axial pressure bearing capacity; the outer protective layer is made of flame-retardant rubber material to form a fire barrier; the layers work in coordination through specific thickness ratios and connection methods to ensure that the layers do not separate or slip under high-pressure conditions, thereby achieving the stability and reliability of the overall structure and meeting the requirements for use under complex working conditions.

[0007] Based on the above technical solution, the wear-resistant and fireproof composite high-pressure pipe of this utility model can be further improved as follows:

[0008] The inner surface of the lining layer is smooth and mirror-like, and the lining layer forms a continuous and seamless bonding surface on the circumferential surface of the tube body.

[0009] The beneficial effects of adopting the above-mentioned improvement scheme are as follows: the inner surface of the lining layer is smooth and mirror-like, and forms a continuous and seamless fit with the circumferential surface of the pipe body, which reduces the frictional resistance of the fluid medium when flowing in the pipe and reduces energy loss; the smooth inner surface avoids the eddies and turbulence that are easily generated by rough surfaces, making the fluid flow more stable; the continuous and seamless fit structure eliminates stress concentration points that are easily generated at the joints, prevents the lining layer from peeling or cracking under high pressure, improves the firmness and durability of the bond between the lining layer and the pipe body, and extends the service life of the high-pressure pipe.

[0010] Furthermore, the intermediate reinforcing layer is composed of 5 to 8 layers of aramid fiber braided layers, with the braiding directions of adjacent aramid fiber layers intersecting perpendicularly to form a grid-like load-bearing structure.

[0011] The beneficial effects of adopting the above-mentioned improved scheme are as follows: the intermediate reinforcing layer is composed of 5 to 8 layers of aramid fiber braided layers, and the braiding directions of adjacent two layers are perpendicular to each other to form a grid-like load-bearing structure. This multi-layered interlaced braiding method enables the aramid fibers to provide effective load-bearing capacity in all directions. When the high-pressure pipe is subjected to internal pressure, the perpendicularly interlaced fiber grid can evenly distribute the pressure to the entire pipe surface, avoiding damage caused by excessive local stress. The multi-layered structure also provides redundant safety protection. Even if a fiber in one layer is locally damaged, the other layers can still maintain the pressure-bearing capacity of the pipe, which significantly improves the burst resistance and safety factor of the high-pressure pipe.

[0012] Furthermore, the outer surface of the outer protective layer is provided with multiple heat dissipation ridges extending along the axial direction of the tube body. The cross-section of the heat dissipation ridges is trapezoidal, and the heat dissipation ridges are evenly distributed on the outer circumferential surface of the tube body.

[0013] The beneficial effects of adopting the above-mentioned improvement scheme are as follows: the outer surface of the outer sheath is provided with trapezoidal cross-section heat dissipation ridges extending along the tube axial direction, which increases the contact area between the outer sheath and the external environment, effectively improving the heat dissipation efficiency of the high-pressure tube; the heat dissipation ridges are distributed along the axial direction and are evenly arranged on the circumferential surface, so that the heat generated by the high-temperature medium inside the tube can be quickly conducted to the outside air through the ridges, avoiding the accumulation of heat inside the tube and the resulting deterioration of material properties; the trapezoidal cross-section structure has good mechanical strength and is not easy to deform or break under external force. At the same time, the side of the trapezoidal structure also increases the heat dissipation area, further enhancing the heat dissipation effect and ensuring the stable operation of the high-pressure tube under high temperature and high pressure environment.

[0014] Furthermore, the wall thickness of the tube remains uniform along the axial direction, and the ratio of the inner diameter to the outer diameter of the tube is maintained within the range of 3:4 to 2:3.

[0015] The beneficial effects of adopting the above-mentioned improvement scheme are as follows: the pipe wall thickness remains uniform along the axial direction, ensuring that the stress distribution in all parts of the pipe is uniform when subjected to internal pressure, avoiding local weak points caused by uneven wall thickness, and preventing stress concentration at weak points that could lead to rupture; the ratio of the inner diameter to the outer diameter of the pipe is maintained within the range of 3:4 to 2:3. This ratio ensures that the pipe has sufficient wall thickness to withstand high pressure, while avoiding material waste and weight increase due to excessive wall thickness; the reasonable diameter-to-thickness ratio allows the pipe to achieve optimal strength performance while maintaining lightweight design, improving the economy and practicality of high-pressure pipes.

[0016] Furthermore, a transition adhesive layer is provided between the inner lining layer and the pipe body. The material of the transition adhesive layer is a high-temperature resistant silicate adhesive, and the thickness of the transition adhesive layer is 1 / 5 to 1 / 10 of the thickness of the inner lining layer.

[0017] The beneficial effects of adopting the above-mentioned improvement scheme are as follows: A transitional bonding layer composed of high-temperature resistant silicate adhesive is set between the inner lining layer and the pipe body. The bonding characteristics of the adhesive are used to firmly bond the ceramic fiber inner lining layer and the metal pipe body, solving the problem of insufficient bonding force caused by the difference in thermal expansion coefficients between the two different materials; the transitional bonding layer, as a buffer medium, can absorb and alleviate the thermal stress generated by temperature changes between the inner lining layer and the pipe body, preventing cracks or peeling at the interface; the thickness of the transitional bonding layer is controlled at 1 / 5 to 1 / 10 of the thickness of the inner lining layer, which not only ensures sufficient bonding strength, but also avoids uneven stress transmission caused by excessive adhesive layer thickness, thereby improving the overall stability and reliability of the composite structure.

[0018] Furthermore, the outer diameter of the flange joint is larger than the outer diameter of the outer sheath, the flange joint is fixed to the end of the pipe body by mechanical crimping, and the material of the flange joint is stainless steel alloy.

[0019] The beneficial effects of adopting the above-mentioned improved scheme are as follows: the design of the flange joint's outer diameter being larger than the outer diameter of the outer protective layer allows the flange joint to completely cover and protect the various layers of the pipe end structure, preventing mechanical damage to the end during installation and use; the flange joint is fixed to the pipe end by mechanical crimping, which provides strong axial tensile resistance and prevents the pipe end from falling off under high pressure; the flange joint is made of stainless steel alloy material, which has excellent corrosion resistance and mechanical strength, and can maintain the reliability of the connection for a long time in harsh environments; the inner circumferential surface of the flange joint is flush with the inner circumferential surface of the pipe, eliminating steps and dead angles at the connection, ensuring smooth fluid flow and reducing pressure loss.

[0020] Furthermore, the aramid fiber weaving density of the intermediate reinforcing layer increases radially from the inside to the outside, with the weaving density of the outermost layer being 1.5 to 2 times that of the innermost layer.

[0021] The beneficial effects of adopting the above-mentioned improvement scheme are as follows: the braiding density of the aramid fiber in the middle reinforcing layer increases gradually from the inside to the outside in the radial direction, with the outermost layer having a braiding density 1.5 to 2 times that of the innermost layer. This gradient braiding density distribution makes the load-bearing capacity of the reinforcing layer gradually increase from the inside to the outside. The lower braiding density of the inner layer ensures good adhesion between the aramid fiber and the tube surface, avoiding fiber bridging caused by excessive braiding. The higher braiding density of the outer layer provides stronger radial restraint, effectively resisting the radial expansion of the tube caused by internal pressure. This gradient structure optimizes the stress distribution, allowing each layer of fiber to fully exert its strength potential, improving material utilization and overall pressure bearing performance.

[0022] Furthermore, the surface of the outer protective layer is provided with an antistatic coating. The material of the antistatic coating is a flame-retardant polymer dispersed in conductive carbon black, and the thickness of the antistatic coating is 1 / 10 to 1 / 20 of the total thickness of the outer protective layer.

[0023] The beneficial effects of adopting the above-mentioned improvement scheme are as follows: the outer sheath surface is provided with an antistatic coating composed of flame-retardant polymers dispersed by conductive carbon black, which effectively prevents safety accidents caused by static electricity accumulation when the high-voltage pipe is transporting flammable and explosive media or in a flammable environment; the antistatic coating conducts surface static electricity in a timely manner through conductive carbon black, keeping the surface potential of the high-voltage pipe within a safe range; the coating thickness is controlled at 1 / 10 to 1 / 20 of the total thickness of the outer sheath, which ensures the antistatic function without affecting the flexibility and heat dissipation performance of the outer sheath due to excessive coating thickness; the flame-retardant polymer matrix maintains the original fireproof performance of the outer sheath, realizing the organic combination of antistatic and fireproof functions, and improving the safety of the high-voltage pipe under special working conditions.

[0024] Furthermore, the height of the heat dissipation ridges is 1 / 3 to 1 / 2 of the thickness of the outer protective layer substrate, the spacing between the heat dissipation ridges is 2 to 3 times the width of the heat dissipation ridges, and the heat dissipation ridges are set parallel to the tube body at an angle of 0°.

[0025] The beneficial effects of adopting the above-mentioned improvement scheme are as follows: the height of the heat dissipation ridges is set to 1 / 3 to 1 / 2 of the thickness of the outer protective layer substrate. This height can significantly increase the heat dissipation area without reducing the mechanical strength or causing damage during handling and installation due to excessive ridge height; the spacing between the heat dissipation ridges is 2 to 3 times the ridge width. This spacing design ensures heat dissipation efficiency while leaving enough space for air circulation, forming a convection heat dissipation channel and enhancing the heat dissipation effect; the heat dissipation ridges are arranged parallel to the pipe body axis, so that the ridge direction is consistent with the main load-bearing direction of the high-pressure pipe. The ridge structure can share part of the axial load, enhance the axial stiffness of the pipe, and the parallel arrangement also facilitates the smooth flow of the fluid medium without generating additional flow resistance.

[0026] Compared with existing technologies, the beneficial effects of the wear-resistant and fire-resistant composite high-pressure pipe provided by this utility model are as follows: This utility model innovatively combines a high-temperature resistant ceramic fiber inner lining, a multi-layered interwoven aramid fiber reinforcement layer, and a flame-retardant rubber outer sheath into the pipe body according to a specific structural relationship, achieving an organic unity of wear resistance, fire resistance, and high pressure resistance; the smooth mirror surface and continuous seamless bonding structure of the inner lining effectively reduce fluid friction resistance and prevent wear; the multi-layered interwoven aramid fiber reinforcement layer evenly disperses internal pressure through a grid-like load-bearing structure, significantly improving the pipe's burst resistance; and the flame-retardant rubber outer sheath, combined with surface heat dissipation embossing and an antistatic coating, not only provides reliable fire protection. It also enhances heat dissipation and electrostatic safety; the layers are connected by various methods such as transition bonding layers, vulcanized bonding, and mechanical pressing to form a solid overall structure, ensuring that the layers do not separate or slip when there are drastic temperature changes and pressure fluctuations; the special design of the flange joint ensures the reliability and sealing of the end connection; the gradient fiber weaving density and optimized geometric parameters make full use of the material properties. Compared with the prior art, this utility model significantly improves the comprehensive performance and service life of the high-pressure pipe while maintaining lightweight, and is particularly suitable for fields with extremely high requirements for safety and reliability, such as petrochemical, aerospace, and fire protection systems, solving the technical problem of insufficient performance of high-pressure pipes under complex working conditions. Attached Figure Description

[0027] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments of this utility model will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is a schematic diagram of the cross-sectional structure of a wear-resistant and fireproof composite high-pressure pipe.

[0029] Figure 2 This is a schematic diagram of the cross-sectional structure of the intermediate reinforcing layer;

[0030] Figure 3 This is a schematic diagram of the flange joint structure;

[0031] The attached diagram lists the components represented by each number as follows:

[0032] 10. Pipe body; 20. Inner lining layer; 30. Outer protective layer; 40. Intermediate reinforcing layer. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings.

[0034] like Figure 1-3 The diagram shows a structural schematic of a wear-resistant and fire-resistant composite high-pressure pipe provided by this utility model. The pipe includes a pipe body 10, an inner lining layer 20, an outer protective layer 30, and an intermediate reinforcing layer 40. The pipe body is a cylindrical structure. The inner lining layer is fitted onto the inner circumferential surface of the pipe body, and the material of the inner lining layer is a high-temperature resistant ceramic fiber composite material. The intermediate reinforcing layer tightly covers the outer circumferential surface of the pipe body and is composed of multiple layers of aramid fiber with a braided structure. The outer protective layer covers the outer surface of the intermediate reinforcing layer and is made of flame-retardant rubber material. The ratio of the radial thickness of the inner lining layer to the wall thickness of the pipe body is 1:3 to 1:5. The braiding angle of each layer of aramid fiber in the intermediate reinforcing layer is distributed in an alternating spiral pattern relative to the axial direction of the pipe body. The outer protective layer and the intermediate reinforcing layer are fixedly connected by vulcanization bonding. Flange joints are provided at both ends of the pipe body, and the inner circumferential surface of the flange joint is flush with the inner circumferential surface of the pipe body.

[0035] In the above technical solution, the inner surface of the lining layer is smooth and mirror-like, and the lining layer forms a continuous and seamless bonding surface on the circumferential surface of the tube body.

[0036] Furthermore, in the above technical solution, the intermediate reinforcing layer is composed of 5 to 8 layers of aramid fiber braided layers, with the braiding directions of adjacent aramid fiber layers intersecting perpendicularly to form a grid-like load-bearing structure.

[0037] Furthermore, in the above technical solution, the outer surface of the outer protective layer is provided with multiple heat dissipation ridges extending along the axial direction of the tube body. The cross-section of the heat dissipation ridges is trapezoidal, and the heat dissipation ridges are evenly distributed on the outer circumferential surface of the tube body.

[0038] Furthermore, in the above technical solution, the wall thickness of the pipe body remains uniform along the axial direction, and the ratio of the inner diameter to the outer diameter of the pipe body is maintained within the range of 3:4 to 2:3.

[0039] Furthermore, in the above technical solution, a transition bonding layer is provided between the inner lining layer and the pipe body. The material of the transition bonding layer is a high-temperature resistant silicate adhesive, and the thickness of the transition bonding layer is 1 / 5 to 1 / 10 of the thickness of the inner lining layer.

[0040] Furthermore, in the above technical solution, the outer diameter of the flange joint is larger than the outer diameter of the outer protective layer, the flange joint is fixed to the end of the pipe body by mechanical crimping, and the material of the flange joint is stainless steel alloy.

[0041] Furthermore, in the above technical solution, the braiding density of the aramid fibers in the intermediate reinforcing layer increases radially from the inside to the outside, and the braiding density of the outermost layer is 1.5 to 2 times that of the innermost layer.

[0042] Furthermore, in the above technical solution, the surface of the outer protective layer is provided with an antistatic coating. The material of the antistatic coating is a flame-retardant polymer dispersed in conductive carbon black, and the thickness of the antistatic coating is 1 / 10 to 1 / 20 of the total thickness of the outer protective layer.

[0043] Furthermore, in the above technical solution, the height of the heat dissipation ridges is 1 / 3 to 1 / 2 of the thickness of the outer protective layer substrate, the spacing between the heat dissipation ridges is 2 to 3 times the width of the heat dissipation ridges, and the heat dissipation ridges are set parallel to the tube body at an angle of 0°.

[0044] The following is a specific embodiment 1 of this utility model: The wear-resistant and fireproof composite high-pressure pipe in this embodiment is made of 304 stainless steel. The outer diameter of the pipe is 50mm, the wall thickness is 8mm, and the length of the pipe is 3000mm. The two ends of the pipe are machined with stepped surfaces to mate with the flange joints by CNC lathe. The machining accuracy of the stepped surfaces is controlled within 0.05mm to ensure a tight fit with the flange joints. The inner lining is made of high-temperature resistant ceramic fiber felt made of alumina ceramic fiber and silicate binder. The ceramic fiber felt is 3mm thick, has a density of 180kg / m3, and can withstand temperatures up to 1200℃. The ceramic fiber felt is evenly coated onto the inner circumferential surface of the pipe using a special coating equipment. During the coating process... Vacuum adsorption technology is used to ensure that there are no air bubbles or gaps between the ceramic fiber felt and the inner surface of the tube, forming a continuous and seamless bonding surface. The inner surface of the lining layer undergoes high-temperature sintering treatment at 1100℃ for 4 hours, resulting in a dense ceramic layer with a surface finish of Ra0.8 or higher, exhibiting a smooth mirror effect. The transition bonding layer uses a high-temperature resistant silicate adhesive, which is made by mixing sodium silicate, alumina powder, and high-temperature resistant filler in a mass ratio of 2:1:1. The adhesive coating thickness is 0.3mm, and it is cured at 200℃ for 2 hours after coating to form a strong bonding layer. The intermediate reinforcing layer is woven from aramid 1414 fibers, with a single filament diameter of 0.The tube is 2mm thick with a tensile strength of 2800MPa. The intermediate reinforcing layer consists of six aramid fiber braided layers. The first layer of aramid fibers is spirally wound at a 45° angle relative to the tube's axial direction, with a braiding density of 20 fibers per square centimeter. The second layer is spirally wound at a negative 45° angle relative to the tube's axial direction, with a braiding density of 22 fibers per square centimeter. The third and fourth layers repeat the braiding pattern of the first and second layers, respectively, but with increased braiding densities of 25 and 27 fibers per square centimeter. The fifth and sixth layers further increase their braiding densities to 30 and 35 fibers per square centimeter, respectively. Appropriate pretension is applied to each layer of aramid fibers during the braiding process to ensure the fibers are tightly adhered to the outer surface of the tube. The outer sheath is made of EPDM (ethylene propylene diene monomer). This flame-retardant rubber is a composite of propylene diene monomer (EPDM) rubber and a halogenated flame retardant. The rubber formulation comprises 60% EPDM rubber by weight, 25% halogenated flame retardant, and the remainder consisting of vulcanizing agents, accelerators, and fillers. The outer sheath is extruded onto the outer surface of the intermediate reinforcing layer, with a thickness of 5mm. After extrusion, it is vulcanized at 160℃ for 30 minutes. The vulcanization process causes chemical cross-linking between the rubber molecules and the aramid fiber surface, forming a strong bond. The outer surface of the sheath is pressed using a special mold to form 12 parallel heat-dissipating ridges extending along the tube's axial direction. The cross-section of each heat-dissipating ridge is trapezoidal, with an upper base width of 4mm, a lower base width of 8mm, and a height of 2mm. The spacing between adjacent heat-dissipating ridges is 18mm. The antistatic coating is uniformly distributed on the outer circumferential surface of the pipe, with an angular interval of 30 degrees. It is made of polyurethane and conductive carbon black composite, with the conductive carbon black accounting for 15% of the total coating mass. The coating is applied to the outer surface of the outer protective layer by spraying, with a thickness of 0.3 mm. After spraying, it is dried at 80℃ for 1 hour to form a uniform and dense antistatic layer. The surface resistivity of the coating is controlled within the range of 10⁶ ohms to 10⁹ ohms, meeting the antistatic requirements. The flange joint is forged from 316 stainless steel, with an outer diameter of 120 mm, an inner diameter of 34 mm (the same as the inner diameter of the pipe), and a flange thickness of 15 mm. Eight bolt holes with a diameter of 14 mm are evenly distributed on the flange, with a center circle diameter of... The flange joints are 95mm thick and are mechanically crimped onto both ends of the pipe body using a hydraulic press at a pressure of 80MPa, with a crimping depth of 20mm. After crimping, ultrasonic testing is performed to ensure that there are no cracks or delamination defects at the crimped joint. The assembled high-pressure pipe undergoes performance testing on a dedicated test bench. The pipe is filled with water and the pressure is gradually increased to 30MPa and held for 30 minutes. Observe that there is no leakage, deformation, or abnormal noise in any part of the pipe. After the pressure stabilizes, the pressure is released, and the pipe is checked to ensure that it returns to its original state, with no separation between the inner lining and the pipe body, and that the intermediate reinforcement layer and the outer protective layer are firmly bonded. During the fire resistance test, the high-pressure pipe is placed in an 800℃ flame environment and continuously heated for 20 minutes. A dense carbonized layer with a thickness of approximately 1mm is formed on the surface of the outer protective layer.The 5mm carbonized layer effectively prevents the flame from spreading inward. After the fire source is removed, the pipe structure remains intact, with no damage to any internal layers. After cooling, the pipe can still withstand the rated working pressure. In the abrasion resistance test, water containing quartz sand particles was flowed through the pipe at a velocity of 6m / s for 500 hours. The thickness loss of the inner lining was less than 0.1mm, and the inner surface remained smooth with no obvious wear marks. In the heat dissipation performance test, hot water at 180℃ was introduced into the pipe at a velocity of 2m / s. After 8 hours of continuous operation, the outer surface temperature was measured. The temperature at the heat dissipation ridges was 95℃, and the temperature at the flat areas between the ridges was 102℃, demonstrating that the heat dissipation ridges effectively reduced the outer surface temperature by approximately 7℃, significantly improving heat dissipation. In the antistatic performance test, the outer surface of the pipe was rubbed in a dry environment, and the surface potential was measured using an electrostatic voltmeter. The highest potential did not exceed 500 volts, far below the safety standard requirement of 2000 volts, proving that the antistatic coating can effectively discharge static electricity.

[0045] The following is another specific embodiment 2 of this utility model: Embodiment 2 is based on Embodiment 1, but replaces the aramid fiber material in the intermediate reinforcing layer with a composite reinforcing layer woven from a mixture of carbon fiber and aramid fiber. The mass ratio of carbon fiber to aramid fiber is 1:2. The addition of carbon fiber further improves the stiffness and tensile strength of the reinforcing layer. The elastic modulus of carbon fiber reaches 230 GPa, far exceeding the 124 GPa of aramid fiber. The overall stiffness of the mixed woven layer is increased by approximately 40%, enabling the pipe to withstand higher working pressures under the same wall thickness. The mixed woven layer still adopts a 6-layer structure, with the weaving angle and weaving density of each layer remaining consistent with Embodiment 1. However, due to the addition of carbon fiber, the unit area mass of each layer increases by about 15%, and the thickness of the outer protective layer increases to 6 mm accordingly to accommodate the change in outer diameter after the stiffness of the reinforcing layer is improved; the crimping pressure of the flange joint is increased to 100 MPa to ensure a firm connection with the pipe body with higher stiffness; the performance test results show that the high-pressure pipe with carbon fiber and aramid fiber mixed reinforcement layer can withstand a maximum pressure of 45 MPa in the pressure bearing capacity test, which is 50% higher than that of Example 1, while the overall mass of the pipe only increases by 12%, achieving a better balance between pressure bearing performance and lightweight. This solution is particularly suitable for applications such as aerospace that are sensitive to weight but have extremely high pressure requirements.

[0046] The following is another specific embodiment 3 of this utility model: Embodiment 3 is based on Embodiment 1, with an additional 1mm thick intumescent fire-retardant coating added between the outer protective layer and the antistatic coating. This intumescent fire-retardant coating is made by mixing ammonium phosphate, pentaerythritol, melamine, and chlorinated paraffin in a mass ratio of 3:2:2:1. At room temperature, the coating is a dense solid film. When exposed to a high-temperature flame, the ammonium phosphate in the coating decomposes to produce phosphoric acid and water vapor. The phosphoric acid further catalyzes the dehydration and carbonization of pentaerythritol to form a porous carbon layer. Melamine decomposes upon heating, releasing large amounts of non-combustible gases such as nitrogen and ammonia, causing the carbon layer to expand and foam, forming a heat-insulating layer 15-20 times thicker than the original coating. This intumescent heat-insulating layer has extremely low thermal conductivity and can effectively isolate the pipe from external flame heat radiation and heat conduction. The intumescent fire-retardant coating is applied by brushing. The coating is applied to the outer surface of the outer protective layer. Before coating, the surface of the outer protective layer is polished to increase the surface roughness and enhance the adhesion of the coating. After coating, it is allowed to dry naturally at room temperature for 24 hours, and then dried in a 60°C environment for 4 hours to ensure that the coating is completely cured. The antistatic coating is applied to the outer surface of the intumescent fireproof coating with a thickness of 0.3 mm. Fire resistance test shows that after adding the intumescent fireproof coating, when heated continuously in a 1000°C flame environment for 30 minutes, the intumescent coating rapidly foams to form a heat-insulating carbon layer with a thickness of about 18 mm. The internal temperature of the pipe only rises to 220°C, which is far lower than the decomposition temperature of the outer protective layer rubber material of 350°C. After the fire source is removed, the pipe structure is intact and undamaged, and the internal layers function normally. The fire resistance is improved by about 60% compared with Example 1. This solution is particularly suitable for dangerous places with high fire risk, such as chemical plants and oil depots.

[0047] Specifically, the principle of this utility model is as follows: The core of this utility model lies in constructing a multi-layer composite structure, enabling each functional layer to work collaboratively through reasonable material selection, geometric design, and connection methods, thereby achieving a comprehensive improvement in wear resistance, fire resistance, and high pressure resistance. The inner lining layer uses high-temperature resistant ceramic fiber composite material. Ceramic fibers have extremely low thermal conductivity and excellent high-temperature resistance, effectively isolating the high-temperature medium from heat conduction to the pipe body, protecting the pipe body from softening and failure due to high temperatures. The ceramic fiber material itself has extremely high hardness and wear resistance, and can maintain the smoothness and integrity of the inner surface for a long time, even when conveying high-speed fluids containing solid particles. The intermediate reinforcing layer uses multi-layer cross-linked... The staggered aramid fiber, a high-strength, high-modulus synthetic fiber, boasts a tensile strength 5 to 6 times that of steel, while its density is only one-fifth that of steel. The three-dimensional mesh formed by the multi-layered staggered weave structure evenly distributes the stress generated by internal pressure in all directions. The perpendicular staggered arrangement of adjacent fiber layers ensures that tensile loads in any direction are shared by multiple fiber layers, avoiding the defect of unidirectional fiber-reinforced structures easily failing in non-dominant directions. The high elastic modulus of aramid fiber also effectively limits the radial expansion of the pipe under high pressure, maintaining the dimensional stability of the pipeline. The outer sheath uses flame-retardant rubber material; the flame retardants added to the flame-retardant rubber can withstand fire. When the flame decomposes, it releases non-flammable gases, dilutes the concentration of flammable gases, and forms a dense carbonized layer on the material surface, preventing the flame from spreading further inward and effectively protecting the internal structure from fire threats. The flexibility of the rubber material can also absorb external mechanical impacts, preventing damage to the pipe due to collisions. The connection method between the layers is also key to achieving overall performance. The transition bonding layer between the inner lining and the pipe body uses a high-temperature resistant silicate adhesive. This adhesive can maintain stable bonding strength at high temperatures, and its moderate flexibility can buffer the thermal stress caused by the difference in thermal expansion coefficients between the ceramic fiber and the metal pipe body. The intermediate reinforcing layer and the outer protective layer are bonded by vulcanization. The chemical bonding process enables rubber molecules to form chemical bonds with the surface of aramid fibers, significantly improving the bonding strength and ensuring that the outer sheath will not peel off from the reinforcing layer under high pressure. The heat dissipation ridges on the surface of the outer sheath increase the heat dissipation area and promote air convection, accelerating heat dissipation and preventing the pipe from deteriorating due to overheating. The antistatic coating establishes a conductive path through conductive carbon black, dissipating static electricity in a timely manner and eliminating the safety hazards of static electricity accumulation. The entire composite structure, through complementary material properties and structural synergy, enables each functional layer to perform its function while supporting each other when the high-pressure pipe is subjected to combined working conditions such as high temperature, high pressure, and wear, fundamentally solving the problem of insufficient performance of single materials or simple composite structures.

[0048] Before use, first inspect the appearance of the high-pressure pipe, confirming that the outer protective layer is free of obvious damage, cracks, or deformation, the heat dissipation ridges are intact and unbroken, and the anti-static coating is evenly applied. Inspect the flange joints at both ends of the pipe, ensuring the flange surfaces are flat and free of rust, and the bolt holes are accurately positioned and free of deformation. Select a high-pressure pipe of appropriate specifications based on the characteristics of the transported medium and the working pressure, ensuring that the rated working pressure of the pipe is at least 1.5 times greater than the maximum working pressure of the system. During installation, align the flange joints at both ends of the high-pressure pipe with the corresponding flanges in the system pipeline, insert the bolts, and tighten them evenly in multiple stages in a diagonal sequence to ensure a tight flange connection and uniform stress distribution. Place a high-temperature resistant sealing gasket between the flange mating surfaces to ensure a tight seal at the connection. Avoid excessive bending during pipe laying; the bending radius should be greater than 10 times the outer diameter of the pipe to avoid excessive stress concentration at bends. The pipe should be secured using appropriate supports. The spacing between supports should not exceed 2 meters to prevent excessive bending of the pipeline due to its own weight or internal pressure. Sufficient heat dissipation space should be maintained around the pipeline to avoid pressing the pipeline against walls or other heat sources, ensuring that the heat dissipation ridges can fully exert their heat dissipation function. Before starting the system, a low-pressure test should be conducted first, and the pressure should be gradually increased to the working pressure, observing whether there are any leaks or abnormal deformations in various parts of the pipeline. During normal operation, the appearance of the pipeline should be checked regularly, paying particular attention to flange connections and pipeline bends. If any abnormalities are found, the system should be stopped and repaired immediately. For applications transporting high-temperature media, the temperature should be increased slowly at the beginning of system startup to avoid internal stress caused by uneven thermal expansion and contraction of the materials in each layer due to rapid temperature changes. Before restarting after a long period of inactivity, a visual inspection and low-pressure test should be conducted again to confirm that the pipeline performance has not been affected. Discarded high-pressure pipes should be disposed of in accordance with relevant environmental protection regulations and should not be discarded at will, causing environmental pollution.

Claims

1. A wear-resistant and fire-resistant composite high-pressure pipe, characterized in that, The device comprises a tube body, an inner lining layer, an outer protective layer, and an intermediate reinforcing layer. The tube body is a cylindrical structure. The inner lining layer is fitted onto the inner circumferential surface of the tube body and is made of a high-temperature resistant ceramic fiber composite material. The intermediate reinforcing layer is tightly wrapped around the outer circumferential surface of the tube body and is composed of multiple layers of aramid fiber with a braided structure. The outer protective layer is wrapped around the outer surface of the intermediate reinforcing layer and is made of flame-retardant rubber material. The ratio of the radial thickness of the inner lining layer to the wall thickness of the tube body is 1:3 to 1:

5. The braiding angle of each layer of aramid fiber in the intermediate reinforcing layer is staggered and spirally distributed relative to the axial direction of the tube body. The outer protective layer and the intermediate reinforcing layer are fixedly connected by vulcanization bonding. Flange joints are provided at both ends of the tube body, and the inner circumferential surface of the flange joint is flush with the inner circumferential surface of the tube body.

2. The wear-resistant and fire-resistant composite high-pressure pipe according to claim 1, characterized in that, The inner surface of the lining layer is smooth and mirror-like, and the lining layer forms a continuous and seamless bonding surface on the circumferential surface of the tube body.

3. The wear-resistant and fire-resistant composite high-pressure pipe according to claim 2, characterized in that, The intermediate reinforcing layer is composed of 5 to 8 layers of aramid fiber braided layers, with the braiding directions of adjacent aramid fiber layers intersecting perpendicularly to form a grid-like load-bearing structure.

4. The wear-resistant and fire-resistant composite high-pressure pipe according to claim 3, characterized in that, The outer surface of the outer protective layer is provided with multiple heat dissipation ridges extending along the axial direction of the tube body. The cross-section of the heat dissipation ridges is trapezoidal and the heat dissipation ridges are evenly distributed on the outer circumferential surface of the tube body.

5. The wear-resistant and fire-resistant composite high-pressure pipe according to claim 4, characterized in that, The wall thickness of the tube remains uniform along the axial direction, and the ratio of the inner diameter to the outer diameter of the tube is maintained within the range of 3:4 to 2:

3.

6. The wear-resistant and fire-resistant composite high-pressure pipe according to claim 5, characterized in that, A transition adhesive layer is provided between the inner lining layer and the pipe body. The material of the transition adhesive layer is a high-temperature resistant silicate adhesive, and the thickness of the transition adhesive layer is 1 / 5 to 1 / 10 of the thickness of the inner lining layer.

7. The wear-resistant and fire-resistant composite high-pressure pipe according to claim 6, characterized in that, The outer diameter of the flange joint is larger than the outer diameter of the outer sheath. The flange joint is fixed to the end of the pipe body by mechanical crimping. The material of the flange joint is stainless steel alloy.

8. The wear-resistant and fire-resistant composite high-pressure pipe according to claim 7, characterized in that, The aramid fiber weaving density of the intermediate reinforcing layer increases radially from the inside to the outside, with the outermost layer having a weaving density that is 1.5 to 2 times that of the innermost layer.

9. The wear-resistant and fire-resistant composite high-pressure pipe according to claim 8, characterized in that, The surface of the outer protective layer is provided with an antistatic coating. The material of the antistatic coating is a flame-retardant polymer dispersed in conductive carbon black. The thickness of the antistatic coating is 1 / 10 to 1 / 20 of the total thickness of the outer protective layer.

10. A wear-resistant and fire-resistant composite high-pressure pipe according to claim 9, characterized in that, The height of the heat dissipation ridges is 1 / 3 to 1 / 2 of the thickness of the outer protective layer substrate, the spacing between the heat dissipation ridges is 2 to 3 times the width of the heat dissipation ridges, and the heat dissipation ridges are set parallel to the tube body at an angle of 0°.

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