A high-pressure steel wire mesh reinforced plastic composite pipe for hydrogen transmission and a method of manufacturing the same

Abstract

The application discloses a high-pressure steel wire mesh reinforced plastic composite pipe for hydrogen transmission and a manufacturing method thereof, and belongs to the technical field of composite pipes. The high-pressure steel wire mesh reinforced plastic composite pipe for hydrogen transmission comprises, from inside to outside, a polymer inner layer, a barrier layer, a steel wire reinforced layer and a polymer outer layer, wherein the polymer inner layer is PA11, the plastic-coated aluminum foil layer can contain EVOH and aluminum foil, PA11, EVOH and aluminum foil all belong to hydrogen barrier materials with excellent hydrogen permeation coefficient, and the three jointly act to block hydrogen permeation by using PA11, and meanwhile, EVOH barrier material is combined with PA11 to avoid the hydrogen passage problem caused by the gap between the traditional spiral aluminum foil, further block hydrogen permeation by combining with the aluminum foil, improve the hydrogen permeation resistance effect, and meanwhile, the composite times between pipes are reduced compared with two-layer composite, the structural stability is improved, and therefore the hydrogen permeation resistance of the high-pressure steel wire mesh reinforced plastic composite pipe for hydrogen transmission is effectively improved.

Description

Technical Field

[0001] This invention belongs to the field of composite pipelines, specifically relating to a high-pressure steel wire mesh reinforced plastic composite pipe for hydrogen transportation and its manufacturing method. Background Technology

[0002] The information disclosed in this background section is intended only to enhance understanding of the overall background of the invention and is not necessarily to be construed as an admission or in any way implying that such information constitutes prior art known to those skilled in the art.

[0003] Plastic composite pipes are currently widely used in water supply and drainage, fire protection, chemical and oil and gas fields. This is mainly due to the combination of reinforcing materials and plastic properties. Currently, composite pipes with polyethylene as the inner and outer plastic layers are widely used in various fields. Among them, steel wire mesh reinforced polyethylene composite pipe is a product with independent intellectual property rights in China and its development is particularly rapid.

[0004] Pipelines, as a crucial link in the hydrogen energy industry, bear the important mission of developing the hydrogen energy industry. Due to the small size of hydrogen atoms, they have a strong permeability to various materials. Currently, most hydrogen pipelines are made of corrosion-resistant steel pipes, but steel pipes are susceptible to hydrogen embrittlement, which significantly impacts the safe operation of pipelines. Current plastic composite pipes, with their inner and outer layers primarily made of polyethylene, also suffer from hydrogen permeation damage, leading to a decline in material properties and consequently causing pipeline safety issues. Addressing the impact of hydrogen damage on pipeline performance is crucial for hydrogen energy transportation.

[0005] Existing composite pipelines already possess relatively complete pressure-bearing structures. However, due to limitations in materials, besides the reinforcing structure, most existing pipelines are made of polymers such as polyethylene and polypropylene. These materials are inherently sensitive to hydrogen permeation, easily leading to hydrogen infiltration and damage. Conventional composite pipelines cannot be used safely for extended periods. Currently, the most pressing issues to be addressed when using non-metallic pipelines for hydrogen transportation are hydrogen permeation and long-term pressure-bearing stability.

[0006] Currently, hydrogen transport composite pipelines are in the early stages of development. The Dutch company Soluforce has launched a hydrogen transport pipeline that uses aluminum foil as the hydrogen barrier layer. Meanwhile, Guangdong Liansu Technology Industry Co., Ltd. (Chinese Patent CN 115264189A) has also proposed using spirally wound double-layer aluminum foil as the main barrier layer, with polyethylene or polyamide as the inner layer material. Aluminum foil is an excellent hydrogen barrier material with superior performance, but it suffers from increased hydrogen migration and permeation due to gaps in the foil winding (caused by these gaps). Furthermore, conventional high-density polyethylene and polyamide materials exhibit varying hydrogen barrier effects, and hydrogen permeation leads to issues such as bubbling and rapid degradation of mechanical properties. Summary of the Invention

[0007] To address the shortcomings of existing technologies, the present invention aims to provide a high-pressure steel wire mesh reinforced plastic composite pipe for hydrogen transportation, its manufacturing method, and its application. To improve the aforementioned performance, the present invention optimizes performance from the perspectives of product structure design and production process, reducing the hydrogen permeability coefficient of the high-pressure steel wire mesh reinforced plastic composite pipe for hydrogen transportation, thus solving the problem of hydrogen permeation damage to the high-pressure steel wire mesh reinforced plastic composite pipe for hydrogen transportation and improving its resistance to hydrogen permeation.

[0008] To achieve the above objectives, the technical solution of the present invention is as follows:

[0009] In a first aspect, the present invention provides a high-pressure steel wire mesh reinforced plastic composite pipe for hydrogen transportation, comprising, from the inside out, a polymer inner layer, a barrier layer, a steel wire reinforcement layer, and a polymer outer layer, wherein the polymer inner layer is polyamide PA11; and the barrier layer is obtained by unidirectionally winding plasticized aluminum foil onto the polymer inner layer.

[0010] The inner polymer layer and the barrier layer are bonded together by heating; the barrier layer, the steel wire reinforcement layer and the outer polymer layer are bonded together by adhesive resin.

[0011] In some embodiments of the present invention, the polymer inner layer is PA11, and the thickness of the polymer inner layer is flexibly designed according to different models. Different polyamides (PAs) have significantly different properties. Compared with commonly used nylon materials such as PA12, PA6, and PA66, PA11 has superior impact resistance. Simultaneously, PA11 has a lower hydrogen permeability coefficient than these PA materials, possessing excellent hydrogen barrier properties and can be used as a standalone hydrogen barrier material in hydrogen transportation pipeline systems. Using Arkema PA11 as the core pipe (i.e., polymer inner layer) material significantly improves the hydrogen permeability resistance of the pipeline compared to conventional nylon used in current product designs. This enhances the pipeline's hydrogen permeability resistance, protects the pipe structure, and effectively utilizes its advantages to ensure pipe safety in buried and submerged applications. The inner tube of the Dutch company Soluforce is made of high-density polyethylene, which has poor resistance to hydrogen permeation and is in direct contact with hydrogen. Before reaching the aluminum barrier layer, hydrogen permeates and damages the inner high-density polyethylene material, which actually damages the overall structure of the product. The polymer inner layer provided by this invention is made of PA11 material, which has excellent hydrogen barrier properties, and can minimize the damage of hydrogen to the overall structure of the pipeline.

[0012] Among the known polymers, EVOH has the best resistance to hydrogen permeation, and aluminum foil is also a material with excellent barrier properties.

[0013] In some embodiments of the present invention, in order to improve the hydrogen barrier capability of high-pressure steel wire mesh reinforced plastic composite pipes for hydrogen transportation, the coated aluminum foil may be provided with an adhesive resin layer and an aluminum foil layer sequentially from the inside to the outside. The coated aluminum foil is unidirectionally wound on the inner polymer layer, and the overlapping of the edges during the winding process improves the overall hydrogen permeation resistance of the pipe.

[0014] Since the hydrogen barrier capability of high-pressure steel wire mesh reinforced plastic composite pipe for hydrogen transportation increases with the increase of aluminum foil layer thickness, the present invention does not limit the thickness of the aluminum foil layer.

[0015] In some embodiments of the present invention, in order to improve the hydrogen barrier capability of high-pressure steel wire mesh reinforced plastic composite pipes for hydrogen transportation, the overmolded aluminum foil includes, from the inside out, an EVOH resin layer and an adhesive resin layer.

[0016] Similarly, since the hydrogen barrier capability of high-pressure steel wire mesh reinforced plastic composite pipes for hydrogen transportation increases with the increase of the thickness of the EVOH resin layer, the present invention does not limit the thickness of the EVOH resin layer.

[0017] Guangdong Liansu Technology Industry Co., Ltd. (Chinese Patent CN 115264189 A) uses a two-layer aluminum foil spiral winding method to improve the overall hydrogen permeation resistance of pipes. However, the bonding resin at the overlap still does not have significant hydrogen permeation resistance, leaving hydrogen permeation pathways. While the double-layer aluminum foil winding method improves hydrogen permeation resistance, it does not consider the impact of hydrogen pathways on the pipe. To address this, this invention uses EVOH, which has excellent hydrogen barrier properties, combined with a single layer of aluminum foil to block hydrogen pathways. Specifically, the coated aluminum foil consists of an EVOH resin layer, a bonding resin layer, and an aluminum foil layer from the inside out. The superimposed process design of the EVOH coating and the winding process avoids the formation of hydrogen permeation pathways by the bonding resin, which originally lacks hydrogen permeation resistance, between the coated aluminum foil layers.

[0018] Similarly, since the hydrogen barrier capability of high-pressure steel wire mesh reinforced plastic composite pipes for hydrogen transportation increases with the increase of the thickness of the EVOH resin layer and the aluminum foil layer, this invention does not limit the thickness of the EVOH resin layer and the aluminum foil layer. For example, the thickness of both the EVOH resin layer and the adhesive resin layer in the overmolded aluminum foil layer can be selected from 0.1-0.15 mm, such as 0.1 mm, 0.12 mm, 0.13 mm, 0.14 mm, 0.15 mm, etc., or a thickness outside this range can also be selected; the thickness of the aluminum foil layer can be selected from 0.1 mm-0.2 mm, such as 0.1 mm, 0.15 mm, 0.2 mm, etc., or a thickness outside this range can also be selected.

[0019] In some embodiments of the present invention, the adhesive resin layer and the EVOH resin layer in the laminated aluminum foil are different colors. If the adhesive resin and EVOH resin materials have the same hue, there is a problem of inaccurate determination of the lamination continuity due to process instability. Distinguishing the inner and outer lamination layers by color can effectively determine the lamination continuity of each layer, which is beneficial for product quality control.

[0020] In some embodiments of the present invention, the coated aluminum foil is unidirectionally spirally wound onto the inner layer of the polymer. During the winding process, the edges of the coated aluminum foil layers overlap vertically, and the winding angle is unrestricted. This layer mainly serves as a barrier, and the winding angle can be flexibly adjusted according to the production speed, pipe diameter, and the width of the coated aluminum foil. The coated aluminum foil adopts a superimposed single-layer winding method, which differs from the existing aluminum foil winding method for non-metallic pipes used for hydrogen transportation. This method utilizes the superimposed hot-melt composite area as an EVOH barrier material composite, avoiding the hydrogen pathway problem formed by the gaps in the traditional spiral-wound aluminum foil, improving the hydrogen permeation resistance effect. At the same time, the number of composite layers between pipes is reduced compared to two-layer composites, increasing structural stability.

[0021] The winding angle can be selected from 20° to 80°. For example, 20°, 37°, 43°, 50°, 62°, 75°, 80°, etc., which can achieve the overlapping of the edges of the plasticized aluminum foil layer.

[0022] The thickness of the overlapping portion at the edge of the coated aluminum foil layer varies with the thickness of the coated aluminum foil layer. For example, when the thickness of both the EVOH resin layer and the adhesive resin layer in the coated aluminum foil layer is selected to be 0.1-0.15 mm, and the thickness of the aluminum foil layer is selected to be 0.1 mm-0.2 mm, the overlapping portion can be controlled within 2 mm. This ensures that the high-pressure steel wire mesh reinforced plastic composite pipe for hydrogen transportation has excellent hydrogen barrier capabilities.

[0023] In some embodiments of the present invention, the steel wire reinforcement layer includes a spiral steel wire mesh, which is embedded within the bonding resin. The spiral steel wire mesh can be reinforced using left- or right-hand spiral woven wire mesh. The wire diameter, number of wires, and number of layers of the wire mesh layer are adjusted according to the required nominal pressure. The spiral steel wire layer and the bonding resin can be stacked multiple times according to the nominal pressure requirements of the pipe. The steel wire mesh is embedded within the bonding resin layer, and the bonding resin effectively covers and fixes the steel wire mesh.

[0024] In some embodiments of the present invention, the bonding resin is maleic anhydride-grafted modified polyethylene.

[0025] In some embodiments of the present invention, the polymer outer layer is polyethylene or polyamide.

[0026] A second aspect of the present invention provides a method for preparing the above-mentioned high-pressure steel wire mesh reinforced plastic composite pipe for hydrogen transportation, comprising the following steps:

[0027] S1. After the aluminum foil surface is preheated, it is coated with plastic.

[0028] S2. PA11 is extruded to obtain a polymer inner layer. After the surface of the inner layer is preheated, the plasticized aluminum foil obtained in S1 is unidirectionally wound around its surface. At the same time, hot air heats the contact surface. The plasticized layer and PA11 are combined to form a plasticized aluminum foil layer. During the plasticized aluminum foil winding process, the edges are stacked one above the other.

[0029] S3. After the spiral steel wire mesh is wrapped around the surface of the plastic-coated aluminum foil layer in S2, it is preheated and then coated with adhesive resin to form a steel wire reinforcement layer. A polymer outer layer is wrapped around the surface of the steel wire reinforcement layer to obtain a high-pressure steel wire mesh reinforced plastic composite pipe for hydrogen.

[0030] In some embodiments of the present invention, the preheating temperature of the aluminum foil surface is 80–120°C, which improves the coating effect on the aluminum foil surface. High-frequency preheating can be used to shorten the preheating time and improve production efficiency.

[0031] In some embodiments of the present invention, in step S1, two layers of lamination are applied to the surface of the aluminum foil. The inner lamination layer uses an adhesive resin, and the outer layer uses EVOH resin to obtain a laminated aluminum foil. The EVOH resin works with the aluminum foil to prevent the generation of hydrogen channels and improve hydrogen barrier capability.

[0032] In some embodiments of the present invention, the EVOH resin and the bonding resin in the coated aluminum foil are prepared by co-extrusion. The extrusion process temperature for the bonding resin can be selected as 210℃-230℃, and the extrusion process temperature for the EVOH resin can be selected as 170℃-220℃. The extrusion speed can be determined according to the production speed. Co-extrusion can improve the bonding force between EVOH and aluminum foil. Since both EVOH and aluminum foil are materials with excellent hydrogen permeation resistance, this provides a double enhancement of hydrogen permeation resistance.

[0033] In some embodiments of the present invention, the surface temperature of the composite of EVOH resin and PA11 in S2 is controlled at 200-240°C. The excellent compatibility between EVOH and PA11 materials is utilized to improve the overall composite effect of the pipeline, resulting in a superior overall composite effect.

[0034] In some embodiments of the present invention, the spiral wire mesh includes left and right spiral woven wire meshes. The diameter of the steel wire, the number of steel wires and the number of layers of the spiral wire mesh are adjusted according to the required nominal pressure. The spiral wire layer and the bonding resin can be stacked multiple times according to the nominal pressure requirements of the pipe. In the steel wire reinforcement layer, the spiral wire mesh is embedded in the bonding resin, and the bonding resin can effectively play a role in covering and fixing the steel wire.

[0035] In some embodiments of the present invention, after the spiral steel wire mesh is wrapped around the surface of the plastic-coated aluminum foil layer in S2, it is first preheated at a temperature of 80–130°C. Similarly, when wrapping the polymer outer layer around the surface of the steel wire reinforcement layer, the steel wire reinforcement layer is first preheated, and then the polymer outer layer is wrapped around its surface at a temperature of 80–130°C.

[0036] The beneficial effects of this invention are as follows:

[0037] This invention provides a high-pressure steel wire mesh reinforced plastic composite pipe for hydrogen transportation, comprising, from the inside out, a polymer inner layer, a barrier layer, a steel wire reinforcement layer, and a polymer outer layer. The polymer inner layer is PA11, and the overmolded aluminum foil layer may contain EVOH and aluminum foil. PA11, EVOH, and aluminum foil are all materials with excellent hydrogen permeability coefficients among hydrogen barrier materials. The three work together, utilizing PA11 to block hydrogen permeation while the overmolded aluminum foil layer further blocks hydrogen permeation. Furthermore, the overmolded aluminum foil is wrapped in a single layer, unlike the existing aluminum foil winding method for non-metallic pipes used in hydrogen transportation. This method utilizes the superimposed hot-melt composite area, where EVOH barrier material is combined with PA11, avoiding the hydrogen pathway problem formed by the gaps in the traditional spiral-wound aluminum foil, thus improving the hydrogen permeation resistance. At the same time, the number of composite layers between pipes is reduced compared to two-layer composites, increasing structural stability. Therefore, this effectively improves the hydrogen permeation resistance of the high-pressure steel wire mesh reinforced plastic composite pipe for hydrogen transportation, with a hydrogen permeability coefficient of only 3.268 × 10⁻⁶. - 16 cm 3 ·m / (cm 2 ·s·Pa). Attached Figure Description

[0038] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0039] Figure 1 This is a structural diagram of the high-pressure steel wire mesh reinforced plastic composite pipe for hydrogen transportation according to the present invention;

[0040] Figure 2 This is a structural diagram of the coated aluminum foil in the high-pressure steel wire mesh reinforced plastic composite pipe for hydrogen transportation of the present invention.

[0041] Wherein, 1: polymer inner layer, 2: plasticized aluminum foil layer, 3: adhesive resin layer, 4: left spiral steel wire mesh layer, 5: right spiral steel wire mesh layer, 6: polymer outer layer, 7: EVOH resin layer, 8: aluminum foil. Detailed Implementation

[0042] To enable those skilled in the art to better understand the technical solution of the present invention, the technical solution of the present invention will be described in detail below with reference to specific embodiments.

[0043] Example 1

[0044] A high-pressure steel wire mesh reinforced plastic composite pipe for hydrogen transportation, such as Figure 1 As shown, from the inside out, it includes a polymer inner layer 1, a plasticized aluminum foil layer 2, a steel wire reinforcement layer, and a polymer outer layer 6.

[0045] Polymer inner layer 1 is Arkema PA11; coated aluminum foil layer 2 is coated aluminum foil, its structure is as follows: Figure 2 As shown, it includes an EVOH resin layer 7, an adhesive resin layer 3, and an aluminum foil 8;

[0046] The polymer inner layer 1 and the plasticized aluminum foil layer 2 are bonded together by heating and melting; the plasticized aluminum foil layer 2, the steel wire reinforcement layer and the polymer outer layer 6 are bonded together by the adhesive resin layer 3, and the adhesive resin layer 3 wraps around the steel wire reinforcement layer.

[0047] Steel wire reinforcement layer such as Figure 1 As shown, it includes an adhesive resin layer 3, a left spiral wire mesh layer 4, and a right spiral wire mesh layer 5; the adhesive resin layer 3 covers the left spiral wire mesh layer 4 and the right spiral wire mesh layer 5, that is, the left spiral wire mesh layer 4 and the right spiral wire mesh layer 5 are embedded inside the adhesive resin layer 3, and the adhesive resin can effectively play a role in covering and fixing the wire mesh.

[0048] The bonding resin layer 3 is a maleic anhydride-grafted modified polyethylene bonding resin.

[0049] The outer polymer layer 6 is made of polyethylene or polyamide.

[0050] On top of that, the polymer inner layer 1 is 5mm thick, the aluminum foil 8 is 0.15mm thick, the adhesive resin layer 3 in the laminated aluminum foil is 0.15mm thick, and the EVOH resin layer 7 is 0.15mm thick.

[0051] The aforementioned high-pressure steel wire mesh reinforced plastic composite pipe for hydrogen transportation can be prepared using the following methods:

[0052] S1. After the surface of aluminum foil 8 is preheated at high frequency (80℃-120℃), two layers of plastic coating are applied to its surface. The inner layer is an adhesive resin layer 3 and the outer layer is an EVOH resin layer 7 to obtain plastic coated aluminum foil. The wall thickness of both plastic coating layers is controlled to be 0.15mm.

[0053] The bonding resin layer 3 and the EVOH resin layer 7 are prepared by co-extrusion. The extrusion process temperature of the bonding resin layer 3 is set at 220℃, and the extrusion process temperature of the EVOH resin layer 7 is set at 195℃. The extrusion speed is determined according to the production speed.

[0054] S2. Arkema PA11 is extruded to obtain polymer inner layer 1. After preheating its surface, the plasticized aluminum foil obtained in S1 is unidirectionally wound (winding angle of 50°) on its surface. It is a single layer of winding, and at the same time, the contact surface is heated by hot air. EVOH resin and PA11 are combined to form plasticized aluminum foil layer 2. The temperature of the composite surface is controlled at 220°C. During the plasticized aluminum foil winding process, the edges are stacked up and down. The thickness of the stacked part after winding is controlled within 2mm.

[0055] S3. After the surface of the plastic-coated aluminum foil layer 2 in S2 is covered with a left-spiral steel wire mesh layer 4 and a right-spiral steel wire mesh layer 5, it is first preheated (105°C), and then adhesive resin is extruded and coated on the surface of the right-spiral steel wire mesh layer 5. The adhesive resin 3 fills the cavity of the steel wire mesh structure. The adhesive resin layer 3 covers the left-spiral steel wire mesh layer 4 and the right-spiral steel wire mesh layer 5 to form a steel wire reinforcement layer. The steel wire reinforcement layer is first preheated (105°C), and then a polymer outer layer 6 is wrapped on its surface to obtain a high-pressure steel wire mesh reinforced plastic composite pipe for hydrogen.

[0056] Example 2

[0057] The difference from Example 1 is that the core tube thickness is designed to be 5mm, the core tube is made of PA11, and the EVOH layer and the core tube are extruded using a co-extrusion process, with the co-extruded EVOH layer controlled at 0.15-0.2mm.

[0058] Example 3

[0059] The difference from Example 1 is that the core tube thickness is designed to be 5mm, the core tube is made of PA11, the aluminum foil is coated using a single-layer adhesive resin layer coating process, and the aluminum foil coating thickness is controlled at 0.15mm.

[0060] Example 4

[0061] The difference from Example 1 is that the core tube thickness is designed to be 5mm, the core tube is made of pipe-grade high-density polyethylene resin, the surface of the core tube is coated with 0.15-0.2mm of maleic anhydride grafted modified polyethylene adhesive resin, the aluminum foil is double-layered and plasticized, and the thickness of the aluminum foil plasticizing layer and the adhesive resin layer are controlled at 0.15mm and EVOH layer respectively.

[0062] Comparative Examples: Examples 1-4 and Comparative Example 1 in Chinese Patent CN 115264189 A.

[0063] Results Test

[0064] Hydrogen permeability tests were conducted on the high-pressure steel wire mesh reinforced plastic composite pipes for hydrogen transportation prepared in Examples 1-3 and the comparative examples above.

[0065] Specific test method: The hydrogen permeability resistance of the sheet composed of the polymer inner layer and the over-plasticized aluminum foil layer in the high-pressure steel wire mesh reinforced plastic composite pipe for hydrogen transportation of this invention was tested using the differential pressure method of GB / T 1038-2000 Test Method for Gas Permeability of Plastic Films and Sheets. This demonstrates the hydrogen permeability resistance of the high-pressure steel wire mesh reinforced plastic composite pipe for hydrogen transportation.

[0066] Table 1. Hydrogen permeability test of high-pressure steel wire mesh reinforced plastic composite pipes for hydrogen transportation.

[0067] serial number <![CDATA[Hydrogen Permeability Coefficient cm 3 ·m / (cm 2 ·s·Pa)]]> Example 1 <![CDATA[3.268×10 -16 <!-- 5 -->]]> Example 2 <![CDATA[4.302×10 -16 ]]> Example 3 <![CDATA[3.921×10 -16 ]]> Example 4 <![CDATA[3.829×10 -16 ]]> CN 115264189 A Example 1 <![CDATA[6.390×10 -16 ]]> CN 115264189 A Example 2 <![CDATA[6.447×10 -16 ]]> CN 115264189 A Example 3 <![CDATA[6.410×10 -16 ]]> CN 115264189 A Example 4 <![CDATA[5.927×10 -16 ]]> CN 115264189 A Comparative Example 1 <![CDATA[1.053×10 -13 ]]>

[0068] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A high-pressure steel wire mesh reinforced plastic composite pipe for hydrogen transportation, comprising, from the inside out, a polymer inner layer, a barrier layer, a steel wire reinforcement layer, and a polymer outer layer, characterized in that, The inner polymer layer is polyamide PA11; the barrier layer is obtained by unidirectionally winding plasticized aluminum foil onto the inner polymer layer. The inner polymer layer and the barrier layer are bonded together by heating; the barrier layer, the steel wire reinforcement layer and the outer polymer layer are bonded together by adhesive resin. Plastic-coated aluminum foil is unidirectionally wound onto the inner layer of polymer, with the edges of the plastic-coated aluminum foil layer overlapping each other during the winding process. The thickness of the overlapping portion at the edge of the coated aluminum foil layer varies with the change of the coated aluminum foil layer, and the overlapping portion can be controlled within 2 mm; The coated aluminum foil comprises, from the inside out, an EVOH resin layer, an adhesive resin layer, and an aluminum foil layer.

2. The high-pressure steel wire mesh reinforced plastic composite pipe for hydrogen transportation as described in claim 1, characterized in that, The adhesive resin layer and the EVOH resin layer in the laminated aluminum foil are different colors, which is used to effectively determine the continuity of each laminated layer.

3. The high-pressure steel wire mesh reinforced plastic composite pipe for hydrogen transportation as described in claim 1, characterized in that, The steel wire reinforcement layer includes a spiral woven steel wire mesh, and the steel wire reinforcement layer is embedded inside the adhesive resin; The spiral woven wire mesh is a left-hand spiral woven wire mesh and / or a right-hand spiral woven wire mesh.

4. The high-pressure steel wire mesh reinforced plastic composite pipe for hydrogen transportation as described in claim 1, characterized in that, The bonding resin is maleic anhydride-grafted modified polyethylene.

5. The high-pressure steel wire mesh reinforced plastic composite pipe for hydrogen transportation as described in claim 1, characterized in that, The outer layer of the polymer is polyethylene or polyamide.

6. A method for preparing a high-pressure steel wire mesh reinforced plastic composite pipe for hydrogen transportation as described in any one of claims 1-5, characterized in that, Includes the following steps: S1. After the aluminum foil surface is preheated, it is coated with plastic. S2. PA11 is extruded to obtain a polymer inner layer. After the surface of the inner layer is preheated, the plasticized aluminum foil obtained in S1 is unidirectionally wound around its surface. At the same time, hot air heats the contact surface. The plasticized layer and PA11 are combined to form a plasticized aluminum foil layer. During the plasticized aluminum foil winding process, the edges are stacked one above the other. S3. After the spiral steel wire mesh is wrapped around the surface of the plastic-coated aluminum foil layer in S2, it is preheated and then coated with adhesive resin to form a steel wire reinforcement layer. A polymer outer layer is wrapped around the surface of the steel wire reinforcement layer to obtain a high-pressure steel wire mesh reinforced plastic composite pipe for hydrogen.

7. The method for preparing the high-pressure steel wire mesh reinforced plastic composite pipe for hydrogen transportation as described in claim 6, characterized in that, In S1, two layers of plastic coating are applied to the surface of the aluminum foil. The inner layer of the plastic coating uses adhesive resin, and the outer layer uses EVOH resin to obtain plastic-coated aluminum foil. In S2, the EVOH resin in the overmolding layer is compounded with PA11, and the hot air temperature is 200-240℃.

8. The method for preparing the high-pressure steel wire mesh reinforced plastic composite pipe for hydrogen transportation as described in claim 6, characterized in that, The spiral wire mesh includes left and right spiral woven wire mesh. The diameter of the steel wire, the number of steel wires and the number of layers of the spiral wire mesh can be adjusted according to the required nominal pressure. The spiral wire layers and the bonding resin can be stacked and configured multiple times according to the nominal pressure requirements of the pipe. In the steel wire reinforcement layer, the spiral steel wire mesh is embedded inside the adhesive resin.

Images