Double-reinforced polyethylene composite pipe and connecting piece

Abstract

The utility model provides a double-reinforced polyethylene composite pipe and a connecting piece, and relates to the field of conveying pipelines. The composite pipe comprises a polyethylene matrix layer, a steel wire reinforcing layer and a protective outer layer which are sequentially stacked from inside to outside, the polyethylene matrix layer is formed by co-extruding PE and PTFE, and the PTFE is extruded as an inner layer; the steel wire reinforcing layer is formed by winding a steel wire of which the surface is coated with maleic anhydride grafted polyethylene adhesive resin at a helical angle of 55 degrees; and the protective outer layer is formed by extruding PE, and a gradient reinforcing layer is arranged in a range of 20cm at the end part of the protective outer layer. The connecting piece comprises a conical bellmouth arranged at the end part, two annular sealing grooves are formed in the inner wall of the conical bellmouth at intervals, and sealing rings are arranged in the annular sealing grooves; and the conical bellmouth is in interference fit with the gradient enhancement layer. Double reinforcement is achieved through the steel wire and the external gradient reinforcement layer, and the bonding strength between the steel wire reinforcement and the polyethylene base body can be improved; meanwhile, the connecting piece can improve the connecting strength and the sealing performance.

Description

Technical Field

[0001] This utility model relates to the field of pipeline transportation, and more specifically, to a double-reinforced polyethylene composite pipe and its connectors. Background Technology

[0002] Polyethylene (PE) pipes are widely used in various fields due to their excellent physical properties, corrosion resistance, sealing performance, and wear resistance. Their applications range from small-section yellow pipes for natural gas to thick-walled black pipes with a diameter of 48 inches used for industrial and municipal pipelines. The use of large-diameter hollow-walled pipes as replacements for concrete rainwater drainage pipes and other sewer lines is also growing rapidly. As the application environments of polyethylene pipes become increasingly complex, the performance requirements for polyethylene pipes are becoming more stringent, leading to extensive research on polyethylene pipes.

[0003] In traditional polyethylene composite pipes, the bonding strength between the steel wire reinforcement and the polyethylene interface is insufficient, making it prone to delamination after long-term use; moreover, the connection strength at the pipe ends is low, making leakage easy and turning them into structural weak points. Utility Model Content

[0004] The purpose of this utility model is to provide a double-reinforced polyethylene composite pipe and connector, which achieves double reinforcement through steel wire and an external gradient reinforcement layer, and can improve the bonding strength between the steel wire reinforcement and the polyethylene matrix; at the same time, the connector with a tapered socket at the end can improve the connection strength and sealing performance.

[0005] The embodiments of this utility model are implemented as follows:

[0006] This application provides a double-reinforced polyethylene composite pipe, comprising a polyethylene matrix layer, a steel wire reinforcement layer, and a protective outer layer stacked sequentially from the inside out.

[0007] The polyethylene matrix layer is formed by co-extrusion of PE and PTFE, wherein the PTFE is extruded as the inner layer;

[0008] The steel wire reinforcement layer is formed by winding steel wires coated with maleic anhydride-grafted polyethylene adhesive resin at a 55° helical angle.

[0009] The protective outer layer is formed by PE extrusion and has a gradient reinforcement layer in the 20cm range at the end.

[0010] Furthermore, based on the aforementioned scheme, an optical fiber sensor array is pre-embedded between the gradient enhancement layer and the protective outer layer.

[0011] Furthermore, based on the aforementioned scheme, the protective outer layer is filled with a microencapsulated healing agent.

[0012] Furthermore, based on the aforementioned scheme, the thickness of the gradient enhancement layer gradually increases by 20% from a distance of 20cm from the port.

[0013] A double-reinforced polyethylene composite pipe connector is provided for connecting the aforementioned composite pipe, wherein a resistance wire is pre-embedded at the end of the composite pipe; the connector includes a tapered socket disposed at the end, wherein two annular sealing grooves are spaced apart on the inner wall of the tapered socket, and a sealing ring is disposed in the annular sealing groove; the tapered socket is interference-fitted with the gradient reinforcement layer.

[0014] Furthermore, based on the aforementioned scheme, the bottom of the annular sealing groove is arc-shaped.

[0015] Furthermore, based on the aforementioned scheme, an annular reinforcing rib is provided at the end of the tapered socket away from the composite pipe, and the annular reinforcing rib protrudes outward from the outside of the connector.

[0016] Furthermore, based on the aforementioned scheme, an NFC chip is embedded in the end face of the tapered socket.

[0017] Furthermore, based on the aforementioned scheme, the taper of the tapered socket is 1:10.

[0018] Furthermore, based on the aforementioned scheme, the connector is made of pure polyethylene, and the gradient reinforcement layer is made of glass fiber reinforced polyethylene.

[0019] Compared with the prior art, the embodiments of this utility model have at least the following advantages or beneficial effects:

[0020] This application utilizes a polyethylene matrix layer formed by co-extrusion of PE and PTFE, with PTFE extruded as the inner layer. This improves the wear resistance of the pipe's inner wall, reduces scaling, and thus enhances the pipe's transport efficiency. A steel wire reinforcement layer is formed by winding steel wire coated with maleic anhydride-grafted polyethylene adhesive resin at a 55° helical angle. The maleic anhydride-grafted polyethylene adhesive resin achieves a good combination of strength and toughness through chemical bonding with the polymer, resulting in a tight bond between the steel wire reinforcement layer and the polyethylene matrix layer. This improves their adhesion and prevents delamination after long-term use. An outer protective layer is formed by PE extrusion, protecting the pipe's exterior. A gradient reinforcement layer is provided within 20cm of the protective layer's end, increasing the strength of the connection points, structurally reinforcing the pipe ends, and optimizing the pipe's mechanical properties.

[0021] By setting a tapered socket at the end of the connector, and the tapered socket being interference-fitted with the gradient reinforcement layer, the stress concentration at the connection can be reduced through the thickness gradient of the reinforcement layer. The interference fit can also improve the pull-out strength of the connection and achieve rapid alignment. By setting two annular sealing grooves at intervals on the inner wall of the tapered socket, and setting sealing rings in the two annular sealing grooves, the double sealing mechanism can improve the sealing performance and maintain the seal even if a single ring fails, ensuring the reliability of the seal. Attached Figure Description

[0022] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a cross-sectional view of the double-reinforced polyethylene composite pipe according to an embodiment of the present utility model;

[0024] Figure 2 This is a cross-sectional view of a double-reinforced polyethylene composite pipe connector according to an embodiment of the present invention;

[0025] Figure 3 This is a cross-sectional view of the connection of the double-reinforced polyethylene composite pipe according to an embodiment of this utility model.

[0026] Icons: 1-Composite pipe, 11-Polyethylene matrix layer, 111-Inner layer, 112-PE layer, 13-Steel wire reinforcement layer, 14-Outer protective layer, 15-Gradient reinforcement layer, 2-Connector, 21-Conical socket, 22-Sealing ring, 23-Annular reinforcing rib. Detailed Implementation

[0027] The embodiments of this application will now be described in detail with reference to the accompanying drawings.

[0028] Please refer to Figure 1 The image shows a schematic diagram of the overall structure of a double-reinforced polyethylene composite pipe.

[0029] This embodiment provides a double-reinforced polyethylene composite pipe, comprising a polyethylene matrix layer 11, a steel wire reinforcement layer 13, and a protective outer layer 14 stacked sequentially from the inside out. The polyethylene matrix layer 11 is formed by co-extrusion of PE and PTFE, wherein the PTFE is extruded as the inner layer 111, and the PE is extruded as the outer PE layer 112, which can improve the wear resistance of the inner wall of the pipe, reduce scale formation, and thus improve the conveying efficiency of the pipe. The steel wire reinforcement layer 13 is formed by winding steel wires coated with maleic anhydride-grafted polyethylene adhesive resin at a 55° helical angle. The ethylene bonding resin can achieve a good combination of strength and toughness through chemical bonding with the polymer, thereby making the steel wire reinforcement layer 13 and the polyethylene matrix layer 11 tightly connected as one, improving the adhesion performance of the two and avoiding delamination after long-term use; the protective outer layer 14 is formed by PE extrusion and has a gradient reinforcement layer 15 set in the end 20cm range, which protects the outside of the pipe; and the gradient reinforcement layer 15 set in the end 20cm range of the protective layer can improve the strength of the connection part, strengthen the structure of the pipe end, and optimize the mechanical properties of the pipe.

[0030] As a preferred embodiment, an optical fiber sensor array is pre-embedded between the gradient enhancement layer 15 and the protective outer layer 14, with an array spacing of 10cm. The optical fiber sensor can monitor the strain and temperature changes of the tube in real time.

[0031] As a preferred embodiment, the outer protective layer 14 is filled with a microencapsulated healing agent, specifically a microencapsulated polysiloxane healing agent. Polysiloxane has good chemical stability and can remain stable under high and low temperature environments, so that it can be automatically released for repair when the tube is damaged, thus extending the service life of the tube.

[0032] In a preferred embodiment, the gradient reinforcement layer 15 is a structural layer with a gradually varying thickness. Its thickness gradually increases by 20% from 20cm away from the port. For example, if the original pipe thickness is 5mm, it gradually increases to 6mm. Furthermore, the length of the gradient reinforcement layer 15 is within 20cm, which can increase the structural strength and pressure-bearing capacity of the pipe end and facilitate the distribution of stress at the connection points.

[0033] Reference Figures 2-3This embodiment provides a connector 2 for a double-reinforced polyethylene composite pipe 1, used to connect the composite pipe 1. The ends of the composite pipe 1 have embedded resistance wires, 2mm wide and spirally arranged at 5mm intervals. The connector 2 includes a tapered socket 21 at the end, used to connect with the pipe. Specifically, the tapered socket 21 is formed by the inner diameter of the connector 2 gradually decreasing from the end inwards, while its outer diameter remains constant, enabling quick and centered connection with the pipe. The tapered socket 21 is interference-fitted with the gradient reinforcement layer 15. The thickness gradient of the gradient reinforcement layer 15 reduces stress concentration at the connection point, and the interference fit improves the pull-out strength of the connection, preventing low connection strength and easy detachment. The inner wall of the tapered socket 21 has two annular sealing grooves spaced apart, each containing a sealing ring 22. The two annular sealing rings 22 form a double-sealing mechanism for the tapered socket 21, maintaining a seal even if a single ring fails, ensuring reliable sealing.

[0034] Furthermore, the tapered socket 21 has a taper of 1:10, which maintains connection stability when there is no external force and needs to overcome additional axial force when under tension. After testing, the pull-out strength of the connector 2 with this taper reaches 4.2MPa. Moreover, the tapered socket 21 with this taper makes the contact pressure evenly distributed, and the compression of the sealing ring 22 is controllable, avoiding excessive compression deformation of the sealing ring 22.

[0035] As a preferred embodiment, the bottom of the annular sealing groove is arc-shaped. The arc-shaped design can reduce stress concentration at this point and avoid phenomena such as cracking and sealing failure.

[0036] As a preferred embodiment, the tapered socket 21 is provided with an annular reinforcing rib 23 at the end away from the composite pipe 1. The annular reinforcing rib 23 protrudes outward from the outside of the connector 2, that is, it is located in the transition area between the tapered socket 21 and the straight pipe section of the connector 2. This can improve the bending strength of the connector 2, disperse the stress to the body of the connector 2, prevent local stress cracking, and increase the structural stability of the connector 2. Moreover, the external design facilitates installation and flaw detection.

[0037] As a preferred implementation, the end face of the tapered socket 21 is embedded with an NFC chip. The chip is connected to the resistance wire circuit through conductive ink and is used to store installation parameters and pressure test data, which enables traceable management of pipeline installation data.

[0038] As a preferred embodiment, the connector 2 is made of pure polyethylene and the gradient reinforcement layer 15 is made of glass fiber reinforced polyethylene. The materials are consistent to ensure welding performance. The mechanical properties of glass fiber reinforced polyethylene are better than those of pure polyethylene. The glass fiber layer first bears plastic deformation, and the pure PE layer 112 serves as the final anti-leakage barrier, improving the overall structural strength of the pipe.

[0039] Furthermore, unless otherwise explicitly specified or limited, the terms "installation" and "connection" in this application embodiment should be interpreted broadly. For example, "connection" can be a detachable connection or a non-detachable connection; it can be a direct connection or an indirect connection through an intermediate medium. The terms "upper," "lower," "left," "right," "inner," "outer," and "side," etc., are merely for reference to the direction in the accompanying drawings or the usual placement of the product during use. They are only for clearly describing this application and do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. They should not be construed as limitations on this application. The terms "first," "second," etc., are only used for distinguishing descriptions and should not be construed as indicating or implying relative importance; "multiple" refers to at least two. In this application embodiment, the limitations on relative positional relationships such as parallel, perpendicular, and aligned are all relative to the current technological level and are not absolutely strict limitations. Slight deviations are allowed; approximations of parallel, perpendicular, and aligned are all acceptable. For example, "A and B are parallel" means that A and B are parallel or approximately parallel, and the angle between A and B can be between 0 degrees and 10 degrees.

[0040] The above are only some embodiments and implementation methods of this application. The protection scope of this application is not limited thereto. In the absence of conflict, the embodiments and features in the embodiments of this application can be combined with each other. Any combination of features in different embodiments is also within the protection scope of this application. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the protection scope of this application.

Claims

1. A dual reinforced polyethylene composite pipe, characterized by, The composite pipe comprises, from inside to outside, a polyethylene matrix layer, a steel wire reinforced layer and a protective outer layer, The polyethylene matrix layer is formed by PE and PTFE co-extrusion, wherein PTFE is extruded as an inner layer; The steel wire reinforced layer is formed by winding steel wires coated with maleic anhydride grafted polyethylene adhesive resin at a spiral angle of 55°; The protective outer layer is formed by PE extrusion, and a gradient reinforced layer is arranged within a range of 20 cm from the end.

2. The dual reinforced polyethylene composite pipe according to claim 1, characterized in that, An optical fiber sensor array is pre-embedded between the gradient reinforced layer and the protective outer layer.

3. The dual reinforced polyethylene composite pipe of claim 1, wherein, The protective outer layer is filled with microencapsulated healing agents.

4. The dual reinforced polyethylene composite pipe of claim 1, wherein, The thickness of the gradient reinforced layer gradually increases by 20% from the end 20 cm away from the port.

5. A dual reinforced polyethylene composite pipe fitting, characterized by, A connector for connecting the composite pipe as claimed in any one of claims 1-4, wherein the end of the composite pipe is pre-embedded with a resistance wire; the connector comprises a tapered socket arranged at the end, two annular sealing grooves are arranged at intervals on the inner wall of the tapered socket, and sealing rings are arranged in the annular sealing grooves; the tapered socket is in interference fit with the gradient reinforced layer.

6. The dual reinforced polyethylene composite pipe coupling of claim 5, wherein, The bottom of the annular sealing groove is arc-shaped.

7. The dual reinforced polyethylene composite pipe coupling of claim 5, wherein, An annular reinforcing rib is arranged at the end of the tapered socket away from the composite pipe, and the annular reinforcing rib protrudes outward from the outer side of the connector.

8. The dual reinforced polyethylene composite pipe coupling of claim 5, wherein, An NFC chip is embedded in the end face of the tapered socket.

9. The dual reinforced polyethylene composite pipe coupling of claim 5, wherein, The taper of the tapered socket is 1:

10.

10. The dual reinforced polyethylene composite pipe coupling of claim 5, wherein, The connector is made of pure polyethylene, and the gradient reinforced layer is glass fiber reinforced polyethylene.

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