Multilayer composite tough and pressure-resistant HDPE plastic pipe structure

Abstract

The utility model discloses a kind of multilayer composite tough compression-resistant HDPE plastic pipe structure, including inner liner, elastic buffer layer, reinforcing support layer and outer cladding, the reinforcing support layer is three-dimensional staggered net structure, and its inside and outside two sides are respectively provided with multiple convex end heads, the outer surface of the inner liner is equipped with inner limiting recess, the inner surface of the outer cladding is equipped with outer limiting recess, the convex end head is respectively embedded in inner limiting recess and outer limiting recess, forming the mechanical occlusion connecting part of through multilayer structure, and the elastic buffer layer inside is equipped with the micropore energy-absorbing unit distributed along axial direction. The multilayer composite tough compression-resistant HDPE plastic pipe structure has higher compressive strength and interlaminar bond force, can effectively resist external pressure and impact, improve overall structural stability and service life.

Description

Technical Field

[0001] This utility model relates to the field of plastic pipe technology, specifically to a multi-layer composite high-strength and pressure-resistant HDPE plastic pipe structure. Background Technology

[0002] High-density polyethylene (HDPE) pipes are widely used in municipal water supply and drainage, gas transmission, and agricultural irrigation due to their excellent corrosion resistance, good flexibility, and ease of construction. To further improve the performance of HDPE pipes in complex environments, various composite HDPE pipe structures have emerged in recent years, using different materials or structural designs to enhance their compressive strength, wear resistance, and service life.

[0003] Currently, most multi-layer HDPE pipes on the market adopt a simple co-extrusion molding process. The materials of each layer are only physically stacked together, lacking an effective structural connection mechanism. This makes them prone to problems such as interlayer delamination and structural failure when subjected to greater external pressure or impact, affecting the overall service life and safety. Furthermore, traditional multi-layer structures mainly rely on increasing thickness or adding fillers to improve compressive strength, which not only increases costs but also limits the development of lightweight pipes. Utility Model Content

[0004] The purpose of this utility model is to provide a multi-layer composite strong and tough HDPE plastic pipe structure to solve the problems mentioned in the background art, such as weak interlayer bonding, limited compressive strength, easy structural failure and short service life of the currently available multi-layer HDPE pipes under external pressure or impact.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a multi-layer composite strong and tough HDPE plastic pipe structure, including an inner lining layer, an elastic buffer layer, a reinforcing support layer, and an outer covering layer. The reinforcing support layer is a three-dimensional interlaced mesh structure with multiple protruding ends on its inner and outer sides. The outer surface of the inner lining layer has an inner limiting groove, and the inner surface of the outer covering layer has an outer limiting groove. The protruding ends are respectively embedded in the inner limiting groove and the outer limiting groove to form a mechanical interlocking connection that penetrates the multi-layer structure. Furthermore, the elastic buffer layer has microporous energy-absorbing units distributed along the axial direction inside.

[0006] Preferably, the reinforcing support layer is composed of multiple support rods inclined at different angles that are interconnected, and the adjacent support rods are connected by transition arc members.

[0007] Preferably, the protruding end is disposed on the inner and outer sides of the reinforcing support layer, and has a triangular pyramidal structure, with its end forming a partially embedded structure in the contact area of ​​the inner lining layer and the outer covering layer.

[0008] Preferably, the inner limiting groove is located on the outer surface of the inner lining layer, and its cross-sectional profile is adapted to the protruding end. The outer limiting groove is located on the inner surface of the outer covering layer, and its distribution position corresponds to the inner limiting groove. The groove depth is consistent with the inner limiting groove.

[0009] Preferably, the microporous energy-absorbing unit is a closed through-hole structure, arranged in a honeycomb pattern and extending through the thickness direction of the elastic buffer layer. The holes of the microporous energy-absorbing unit are separated by thin-walled partitions, and the thickness of the thin-walled partitions is less than half the diameter of the holes.

[0010] Preferably, the outer covering layer is provided with an annular limiting step, which is arranged in a ring at equal intervals, with a height of 0.3mm-0.6mm and an edge with a beveled transition structure.

[0011] Compared with existing technologies, the beneficial effects of this utility model are as follows: This multi-layer composite high-strength and pressure-resistant HDPE plastic pipe structure has higher compressive strength and interlayer bonding force, effectively resisting external pressure and impact, and improving the overall structural stability and service life. This structure, through the three-dimensional interlaced mesh design of the reinforced support layer, and the mechanical interlocking connection formed by the protruding ends on its inner and outer sides with the inner limiting groove of the inner lining layer and the outer limiting groove of the outer covering layer, achieves structural linkage and stable bonding between the layers. Simultaneously, the microporous energy-absorbing units inside the elastic buffer layer can absorb energy and buffer stress under load, further enhancing the pipe's impact resistance and long-term reliability in complex environments. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the structure of a multi-layer composite high-strength and pressure-resistant HDPE plastic pipe according to the present invention.

[0013] Figure 2 This is a schematic diagram of the elastic buffer layer structure of a multi-layer composite strong and tough HDPE plastic pipe structure according to the present invention;

[0014] Figure 3 This is a partial structural diagram of the connection between the inner lining layer and the outer covering layer of a multi-layer composite strong and tough HDPE plastic pipe structure according to this utility model.

[0015] Figure 4 This is a schematic diagram of the external structure of the outer covering layer of a multi-layer composite strong and pressure-resistant HDPE plastic pipe structure according to this utility model.

[0016] In the figure: 1. Inner lining layer; 101. Inner limiting groove; 2. Elastic buffer layer; 201. Microporous energy absorption unit; 202. Thin-walled partition; 3. Reinforcing support layer; 301. Protruding end; 302. Support rod; 303. Transition arc component; 4. Outer covering layer; 401. Outer limiting groove; 402. Annular limiting step. Detailed Implementation

[0017] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0018] Please see Figure 1-4This utility model provides a technical solution: a multi-layer composite high-strength and pressure-resistant HDPE plastic pipe structure, including an inner liner 1, an elastic buffer layer 2, a reinforcing support layer 3, and an outer covering layer 4. The inner liner 1, elastic buffer layer 2, reinforcing support layer 3, and outer covering layer 4 are arranged sequentially from the inside out. The inner liner 1 is made of high-density polyethylene (HDPE), which has good corrosion resistance and basic pressure bearing capacity. The elastic buffer layer 2 is made of modified thermoplastic polyurethane (TPU) or foamed HDPE, possessing excellent elasticity and energy absorption properties. The reinforcing support layer 3 is composed of glass fiber reinforced polypropylene or engineering plastics, possessing high strength, rigidity, and dimensional stability. The outer covering layer 4 is still mainly made of HDPE, and the surface can be modified with UV-resistant or wear-resistant modifiers as needed to improve external protection performance. This multi-layer structure adopts a co-extrusion molding process, with each layer forming simultaneously in a high-temperature molten state. The reinforcing support layer 3 has a three-dimensional interlaced mesh structure. Multiple protruding ends 301 are provided on the inner and outer sides of the reinforcing support layer 3. The outer surface of the inner liner layer 1 has an inner limiting groove 101, and the inner surface of the outer covering layer 4 has an outer limiting groove 401. The protruding ends 301 are respectively embedded in the inner limiting groove 101 and the outer limiting groove 401, forming a mechanical interlocking connection that penetrates the multi-layer structure. Furthermore, the elastic buffer layer 2 contains microporous energy-absorbing units 201 distributed axially. When subjected to external pressure or impact, the three-dimensional interlaced mesh structure inside the reinforcing support layer 3 can quickly and evenly distribute the stress throughout the entire structural system. Simultaneously, the multiple protruding ends 301 on the inner and outer sides of the reinforcing support layer 3... Each protruding end 301 forms a tight fit with the inner limiting groove 101 on the outer surface of the inner lining layer 1 and the outer limiting groove 401 on the inner surface of the outer covering layer 4, constituting a mechanical interlocking connection that penetrates the multi-layer structure. This allows for a firm connection between the layers through physical structure, avoiding the interlayer delamination problem caused by traditional multi-layer structures that rely solely on surface bonding or simple stacking. Simultaneously, the microporous energy-absorbing units 201 distributed axially within the elastic buffer layer 2 undergo controllable compressive deformation under stress, effectively absorbing and dissipating impact energy and reducing local stress concentration. This further enhances the overall structure's compressive strength and toughness. Overall, this significantly improves the stability and load-bearing capacity of the pipe under complex working conditions. It also achieves the technical goal of improving comprehensive mechanical properties without increasing wall thickness, solving the technical problems of low interlayer bonding strength, limited compressive strength, and high cost and limited lightweighting caused by reliance on thickening or fillers in existing HDPE multilayer pipes. The reinforcing support layer 3 is composed of multiple support rods 302 with different angles that are interconnected, and adjacent support rods 302 are connected by transition arc members 303. When the pipe is subjected to external pressure or local impact, the support rods 302 can effectively disperse the external force in multiple directions, avoiding stress concentration in a certain local area. At the same time, the transition arc members 303 not only improve the overall strength of the structure, but also enhance the deformation adaptability under stress.To ensure the reinforcing support layer 3 maintains a certain degree of flexibility while possessing high rigidity, protruding ends 301 are located on the inner and outer sides of the reinforcing support layer 3, forming a triangular pyramidal structure. Their ends form a partially embedded structure with the contact area between the inner lining layer 1 and the outer covering layer 4. This structure provides excellent guidance and fitting properties, allowing the protruding ends 301 to smoothly embed into the inner limiting groove 101 and the outer limiting groove 401 during pipe forming, creating a mechanically interlocking connection that penetrates the multi-layer structure. This effectively prevents relative sliding or interlayer peeling of the layers under external pressure or shear force, thereby significantly improving the overall compressive strength and length of the pipe structure. To ensure reliable operation, the inner limiting groove 101 is located on the outer surface of the inner liner 1, and its cross-sectional profile matches the protruding end 301. The outer limiting groove 401 is located on the inner surface of the outer covering layer 4, and its distribution corresponds to that of the inner limiting groove 101, with the same groove depth. This consistency and symmetry between the inner and outer limiting grooves 101 further enhances the overall structural stability and deformation resistance, allowing the pipe to maintain good integrity even under complex loads. The microporous energy-absorbing unit 201 is a closed-loop through-hole structure, arranged in a honeycomb pattern, and penetrates the elastic buffer layer 2. In the dimensional direction, the pores of the microporous energy-absorbing unit 201 are separated by thin-walled partitions 202, and the thickness of the thin-walled partitions 202 is less than half the pore diameter. This structure allows the microporous energy-absorbing unit 201 to undergo controllable compression deformation through the thin-walled partitions 202 when the pipe is subjected to external pressure or impact, achieving effective energy absorption and dissipation. This significantly improves the impact resistance and rebound recovery capability of the elastic buffer layer 2. Simultaneously, the thin-walled partitions 202 ensure that the overall structure possesses sufficient supporting stiffness while maintaining good deformation adaptability, effectively alleviating stress concentration without significantly increasing material usage and preventing damage caused by excessive localized stress. To prevent structural damage, the outer sheath 4 is equipped with an annular limiting step 402, which is evenly spaced and 0.3mm-0.6mm high with beveled edges. This annular limiting step 402 not only provides additional mechanical support and positioning, but also enhances the stability and accuracy of the pipe during installation. Furthermore, it effectively disperses externally applied pressure, preventing deformation or damage caused by localized stress concentration, thereby improving the overall structural durability and reliability.

[0019] Working principle: When using this multi-layer composite strong and tough HDPE plastic pipe structure, the pipe is first laid according to the engineering requirements and the interface connection is completed. Under the action of external force, the external pressure is initially contacted and transmitted to the overall structure through the annular limiting step 402 on the surface of the outer covering layer 4. Then the pressure continues to be transmitted inward to the three-dimensional interlaced mesh structure of the reinforcing support layer 3, and through the multiple protruding ends 301 set on its inner and outer sides, it acts on the inner limiting groove 101 on the outer surface of the inner liner layer 1 and the outer limiting groove 401 on the inner surface of the outer covering layer 4 respectively. At the same time, the structure formed by the cross connection of multiple support rods 302 with different angles inside the reinforcing support layer 3 realizes the dynamic distribution of stress during the force process. The force path is smoothly transitioned between the support rods 302 through the transition arc part 303, further guiding the pressure into the elastic buffer layer 2 area. The microporous energy absorption unit 201 undergoes structural compression during continuous pressure, forming a deformation response at the material level, thereby completing a series of tasks.

[0020] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A multi-layer composite high-strength and pressure-resistant HDPE plastic pipe structure, comprising an inner lining layer (1), an elastic buffer layer (2), a reinforcing support layer (3), and an outer covering layer (4), characterized in that: The reinforcing support layer (3) is a three-dimensional interlaced mesh structure. Multiple protruding ends (301) are provided on the inner and outer sides of the reinforcing support layer (3). The outer surface of the inner lining layer (1) is provided with an inner limiting groove (101). The inner surface of the outer covering layer (4) is provided with an outer limiting groove (401). The protruding ends (301) are respectively embedded in the inner limiting groove (101) and the outer limiting groove (401) to form a mechanical interlocking connection part that penetrates the multi-layer structure. The elastic buffer layer (2) is provided with microporous energy-absorbing units (201) distributed along the axial direction.

2. The multi-layer composite high-strength and pressure-resistant HDPE plastic pipe structure according to claim 1, characterized in that: The reinforcing support layer (3) is composed of multiple support rods (302) with different angles of inclination, which are connected to each other in a cross manner, and the support rods (302) are connected to each other by transition arc members (303).

3. The multi-layer composite high-strength and pressure-resistant HDPE plastic pipe structure according to claim 1, characterized in that: The protruding end (301) is located on the inner and outer sides of the reinforcing support layer (3) and has a triangular pyramidal structure. Its end forms a partially embedded structure with the contact area of ​​the inner lining layer (1) and the outer covering layer (4).

4. The multi-layer composite high-strength and pressure-resistant HDPE plastic pipe structure according to claim 3, characterized in that: The inner limiting groove (101) is located on the outer surface of the inner lining layer (1), and its cross-sectional profile is adapted to the protruding end (301). The outer limiting groove (401) is located on the inner surface of the outer covering layer (4), and its distribution position corresponds to the inner limiting groove (101). The groove depth is consistent with the inner limiting groove (101).

5. The multi-layer composite high-strength and pressure-resistant HDPE plastic pipe structure according to claim 1, characterized in that: The microporous energy-absorbing unit (201) is a closed through-hole structure, arranged in a honeycomb pattern and extending through the thickness direction of the elastic buffer layer (2). The holes of the microporous energy-absorbing unit (201) are separated by thin-walled partitions (202), and the thickness of the thin-walled partitions (202) is less than half the diameter of the holes.

6. The multi-layer composite high-strength and compression-resistant HDPE plastic pipe structure according to claim 1, characterized in that: The outer covering layer (4) is provided with an annular limiting step (402) on the outside. The annular limiting step (402) is arranged in a ring with equal spacing, and its height is 0.3mm-0.6mm. The edge has a beveled transition structure.

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