A connecting head structure suitable for DN110~1200 composite pipe

Abstract

The utility model discloses a kind of connector structures suitable for DN110~1200 composite pipe, specifically is: in the end of two sections of composite pipe injection molding one connector with stepped shape outer diameter, when two composite pipes are connected, the big head of two connectors is attached;Flange connection or hot melt butt joint connection is used at the step of two connectors;Several holes are provided on the composite pipe at the connector, and the hole is the tensile column of connector.The utility model is suitable for pipe diameter DN110-DN1200 of water supply and drainage, chemical pipeline etc., satisfies 10.0MPa high pressure, 6.4MPa medium pressure, 1.6MPa low pressure demand.

Description

Technical Field

[0001] This utility model belongs to the field of pipe connection technology, and in particular relates to a connector structure suitable for composite pipes of DN110 to 1200. Background Technology

[0002] Existing fiber composite pipe connector designs (such as electrofusion, snap-fit, and hot-melt) are mostly designed for specific pipe diameters (e.g., below DN315) and single material combinations (e.g., PE + glass fiber), exhibiting significant limitations. Snap-fit ​​connections are prone to fiber breakage in the reinforcing layer, while electrofusion and hot-melt connections are insufficient in tensile strength and sealing performance, especially under high pressure (above 10.0 MPa) or large diameter (DN1200) conditions. The lack of universal design solutions for different pressure levels increases the risk of joint failure. While existing hot-melt butt welding technology is suitable for low pressure, the relationship between connector thickness and pressure is not fully optimized, making it difficult to meet medium and high pressure requirements. Furthermore, existing technologies do not fully utilize the potential of perforation to reinforce the inner and outer layers and the tensile strength and sealing effect achieved by filling the holes during injection molding. Therefore, an innovative design that can adapt to multiple pressure levels and optimize connection reliability through perforation is urgently needed. Utility Model Content

[0003] This utility model aims to provide a design and manufacturing method for connectors suitable for continuous fiber-wound reinforced composite pipes from DN110 to DN1200. The thickness A of the connector is optimized for three pressure levels: high pressure (10.0MPa), medium pressure (6.4MPa), and low pressure (1.6MPa). Holes are drilled at the connector position to enhance mechanical engagement, thus overcoming the shortcomings of the prior art.

[0004] This utility model discloses a connector structure suitable for composite pipes with diameters ranging from DN110 to 1200. A stepped connector with an outer diameter is injection-molded at each end of two composite pipe sections. When the two pipes are connected, the larger ends of the two connectors fit together. Flanges or butt-welded connections are used at the stepped sections of the two connectors. Several holes are provided on the composite pipe at the connector, and the holes contain tensile supports for the connector.

[0005] Furthermore, the inner and outer layers of the composite pipe are made of PE, PERT, PPR or PP, and the reinforcing layer is made of glass fiber, carbon fiber, aramid fiber or basalt fiber.

[0006] Furthermore, the thickness of each layer in the composite pipe is determined according to the pipe diameter: the outer layer thickness is 3.0-15.0 mm, the inner layer thickness is 3.2-30.0 mm, and the reinforcement layer thickness is 2.0-10.0 mm.

[0007] Furthermore, the connection length between the connector and the outer layer of the composite pipe is 100-500mm, the oxide layer is removed, and the inner layer is peeled off by 1.6-500mm.

[0008] Furthermore, the thickness A of the connector is determined according to the pressure rating: 80-150mm for high pressure 10.0MPa, 20-42mm for medium pressure 6.4MPa, and 2.0-4.2mm for low pressure 1.6MPa.

[0009] Furthermore, the diameter of the holes is 10-115mm, and the number is 7-73, with the diameter and number determined according to the diameter of the composite pipe.

[0010] Furthermore, the flange has an L-shaped cross-section, with the inner wall of the flange tightly fitted to the small end of the connector. Several bolt holes are provided on the vertical surface of the flange, and the two flanges are connected and fixed by connecting bolts.

[0011] Furthermore, a water-stop ring is installed between the two composite pipe sections.

[0012] The beneficial technical effects of this utility model are as follows:

[0013] This utility model is applicable to water supply and drainage, chemical pipelines, and other pipelines with pipe diameters of DN110-DN1200, meeting the requirements for 10.0MPa high pressure, 6.4MPa medium pressure, and 1.6MPa low pressure. It optimizes the calculation method of the relationship between connector thickness A and pressure, and by drilling holes in the pipe and filling the holes during injection molding of the joint to form tensile columns, it strengthens the connection between the inner and outer walls, firmly bonding the connector to the composite pipe. The tensile columns and the fiber winding layer also create tensile resistance, ensuring tensile strength and sealing performance. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the overall structure of this utility model.

[0015] Figure 2 This is a cross-sectional view of the overall structure of this utility model.

[0016] Figure 3 This is a schematic diagram showing the positions of a composite pipe section, connector, and flange of this utility model.

[0017] Figure 4 This is a dimensional schematic diagram of one embodiment of the present invention.

[0018] Figure 5 This is a dimensional schematic diagram of an embodiment of the present utility model.

[0019] In the diagram: 1-Composite pipe; 2-Connector; 21-Large end of connector; 22-Small end of connector; 3-Flange; 31-Flange plate; 32-Connecting bolt; 4-Hole; 5-Water-stop ring; 6-Tension column. Detailed Implementation

[0020] The present invention will now be described in further detail with reference to the accompanying drawings and specific implementation methods.

[0021] This utility model provides a connector structure suitable for composite pipes with diameters from DN110 to 1200, as follows: Figure 1 As shown, a stepped connector 2 is injection molded at each end of the two composite pipe sections 1. When the two composite pipe sections 1 are connected, the larger ends 21 of the two connectors 2 fit together. Figure 2 As shown, flanges 3 or hot-melt butt connections are used at the stepped joints 2. Figure 4 As shown, several holes 4 are provided on the composite pipe 1 at the connector 2, and the tensile columns 6 of the connector are located inside the holes 4.

[0022] Furthermore, the inner and outer materials of the composite pipe 1 are selected from PE, PERT, PPR or PP, and the reinforcing layer material is selected from glass fiber, carbon fiber, aramid fiber or basalt fiber.

[0023] Furthermore, the thickness of each layer of the composite pipe 1 is determined according to the pipe diameter, with the outer layer thickness being 3.0-15.0 mm, the inner layer thickness being 3.2-30.0 mm, and the reinforcing layer thickness being 2.0-10.0 mm.

[0024] The relationship between the selection of the reinforcing layer thickness and the diameter of composite pipe 1 is shown in Table 1.

[0025] Table 1. Relationship between pipe diameter, connector thickness A, and reinforcement layer thickness (unit: mm)

[0026]

[0027]

[0028] Furthermore, the outer connection length between connector 2 and composite pipe 1 is 100-500mm, the oxide layer is removed, and the inner layer is peeled off by 1.6-500mm.

[0029] The detailed parameters of the connector and the relationship between the pipe diameter are shown in Table 2.

[0030] Table 2. Relationship between pipe diameter, connector parameters, and hole parameters (unit: mm)

[0031]

[0032]

[0033] Furthermore, the thickness A of connector 2 is determined according to the pressure rating: 80-150mm for high pressure 10.0MPa, 20-42mm for medium pressure 6.4MPa, and 2.0-4.2mm for low pressure 1.6MPa.

[0034] The relationship between the connector thickness A and the diameter of the composite pipe 1 is also shown in Table 1.

[0035] Furthermore, the diameter of hole 4 is 10-115mm, and the number is 7-73. The diameter and number are determined according to the diameter of composite pipe 1.

[0036] The relationship between the parameters of the holes (diameter and number) and the diameter of the composite pipe 1 is also shown in Table 2.

[0037] Furthermore, such as Figure 2 , Figure 3 As shown, the flange 31 of the flange 3 has an L-shaped cross section. The inner wall of the flange 31 is tightly attached to the small end 22 of the connector 2. Several screw holes are opened on the vertical surface of the flange 31. The two flanges 31 are connected and fixed by connecting screws 32.

[0038] Furthermore, such as Figure 4 , Figure 5 As shown, a water-stop ring 5 is also installed between the two sections of composite pipe 1.

[0039] Manufacturing process of this utility model:

[0040] 1. Select the material and thickness according to the pipe diameter, and then wind the reinforcing layer (refer to Table 1). The inner and outer layers of the composite pipe are made of PE, PERT, PPR, or PP, while the reinforcing layer material is made of glass fiber, carbon fiber, aramid fiber, or basalt fiber. The thickness of each layer of the composite pipe is determined according to the pipe diameter: outer layer thickness 3.0-15.0 mm, inner layer thickness 3.2-30.0 mm, and reinforcing layer thickness 2.0-10.0 mm.

[0041] 2. Process the connector. The connection length between the connector and the outer layer of the composite pipe is 100-500mm. Remove the oxide layer, and peel off 1.6-500mm of the inner layer. The connector thickness A is determined according to the pressure rating: 80-150mm for high pressure (10.0MPa), 20-42mm for medium pressure (6.4MPa), and 2.0-4.2mm for low pressure (1.6MPa) (refer to Table 2).

[0042] 3. Drill holes at the connector, with a diameter of 10-115mm and a quantity of 7-73 holes. The hole diameter and quantity should be adjusted according to the pipe diameter and pressure (refer to Table 2).

[0043] 4. Heat to a molten state using a hot air box at a temperature of 220-250℃ and a surface temperature of 190-220℃ for 60-150 seconds (adjusted according to pipe diameter), and monitor using an infrared thermometer.

[0044] 5. Hot melt butt welding: Align the two connectors, heat to a molten state, apply appropriate pressure to fuse, and cool for 5-10 minutes.

[0045] 6. Conduct pull-out and burst tests to verify performance. Pull-out tests verify tensile strength and pressure requirements, while burst tests verify that the sealing performance meets the corresponding pressure rating.

[0046] Case study of tensile strength analysis:

[0047] Case 1: High pressure (10.0MPa), DN1200

[0048] Parameters: Outer diameter 1200mm, total wall thickness 30mm, inner diameter 1140mm, outer layer 15mm, inner layer 10mm, reinforcing layer 5mm, thickness A 150mm, outer layer connection length 460mm, number of holes 73, hole diameter 115mm.

[0049] • Axial force: F = 10.0 × 10 6 ·π·(1140 / 2) 2 ≈1.62·10 7 N.

[0050] • Tensile strength requirement: F 设计 =1.62·10 7 / 1.5≈1.08·10 7 N.

[0051] • Outer layer contribution: Cross-sectional area A of the outer PE layer 外层 =15·460·π·1.20≈2.60·10 4 mm 2 Tensile strength F 外层 =25·10 6 ·2.60·10 4 ·10 -6 ≈6.50·10 5 N.

[0052] • Inner layer contribution: Cross-sectional area A of the inner PE layer 内层 =10·460·π·1.14≈1.65·10 4 mm 2 Tensile strength F 内层 =25·10 6 ·1.65·10 4 ·10 -6 ≈4.13·10 5 N.

[0053] • Contribution of perforated columns: 73 perforated columns, with a perforated column cross-sectional area A 孔柱 =π·(115) 2 / 4·73≈7.58·10 5 mm 2 Tensile strength F 孔柱 =25·106 ·7.58·10 5 ·10 -6 ≈1.90·10 7 N.

[0054] Total tensile strength: F 总 =F 外层 +F 内层 +F 孔柱 ≈6.50·10 5 +4.13·10 5 +1.90·10 7 ≈1.99·10 7 N, far exceeding demand by 1.08·10 7 N. Case 2: Medium pressure (6.4MPa), DN400

[0055] Parameters: Outer diameter 400mm, total wall thickness 18mm, inner diameter 364mm, outer layer 3mm, inner layer 7mm, reinforcing layer 8mm, thickness A 30mm, outer layer connection length 149.6mm, number of holes 24, hole diameter 37.4mm.

[0056] Axial force: F = 6.4 × 10 6 ·π·(364 / 2) 2 ≈6.68·10 5 N.

[0057] • Tensile strength requirement: F 设计 =6.68·10 5 / 1.5≈4.45·10 5 N.

[0058] • Outer layer contribution: Cross-sectional area A of the outer PE layer 外层 =3·149.6·π·0.40≈5.64·10 3 mm 2 Tensile strength F 外层 =25·106·5.64·10 3 ·10 -6 ≈1.41·10 5 N.

[0059] • Inner layer contribution: Cross-sectional area A of the inner PE layer 内层 =7·149.6·π·0.364≈1.20·10 4 mm 2 Tensile strength F 内层 =25·106·1.20·10 4 ·10 -6 ≈3.00·10 5 N.

[0060] • Contribution of perforated columns: 24 perforated columns, with a perforated column cross-sectional area A 孔柱 =π·(37.4) 2 / 4·24≈2.64·10 5 mm 2 Tensile strength F 孔柱 =25·106·2.64·10 5 ·10 -6 ≈6.60·10 6 N.

[0061] Total tensile strength: F 总 =F 外层 +F 内层 +F 孔柱 ≈1.41·10 5 +3.00·10 5 +6.60·10 6 ≈6.94·10 6 N, far exceeding demand by 4.45·10 5 N. Case 3: Low pressure (1.6MPa), DN110

[0062] Parameters: Outer diameter 110mm, total wall thickness 8.2mm, inner diameter 93.6mm, outer layer 3mm, inner layer 3.2mm, reinforcing layer 2.0mm, thickness A 2.0mm, outer layer connection length 42.4mm, number of holes 7, hole diameter 10.6mm.

[0063] • Axial force: F = 1.6 × 10⁶ × π × (93.6 / 2) 2 ≈1.10·10 4 N.

[0064] • Tensile strength requirement: F 设计 =1.10·10 4 / 1.5≈7.33·10 3 N.

[0065] • Outer layer contribution: Cross-sectional area A of the outer PE layer 外层 =3·42.4·π·0.11≈4.41·10 2 mm 2 Tensile strength F 外层 =25·106·4.41·10 2 ·10 -6 ≈1.10·10 4 N.

[0066] • Inner layer contribution: Cross-sectional area A of the inner PE layer 内层 =3.2·42.4·π·0.0936≈4.01·10 2 mm2 Tensile strength F 内层 =25·106·4.01·10 2 ·10 -6 ≈1.00·10 4 N.

[0067] • Contribution of the perforated columns: 7 perforated columns, with a perforated column cross-sectional area A 孔柱 =π·(10.6) 2 / 4·7≈6.19·10 2 mm 2 Tensile strength F 孔柱 =25·106·6.19·10 2 ·10 -6 ≈1.55·10 4 N.

[0068] Total tensile strength: F 总 =F 外层 +F 内层 +F 孔柱 ≈1.10·10 4 +1.00·10 4 +1.55·10 4 ≈3.65·10 4 N, far exceeding demand 7.33·10 3 N.

[0069] Calculation basis

[0070] • Axial force: F=P·π·(D / 2) 2

[0071] • Tensile strength requirement: F 设计 =F / 1.5

[0072] Thickness A: A = F 设计 / σ·π·D·L, where σ=25MPa(PE) and L is the connection length (0.1-0.5m).

Claims

1. A connector structure suitable for composite pipes of DN110~1200, characterized in that, A stepped connector (2) is injection molded at the ends of the two composite pipes (1). When the two composite pipes (1) are connected, the large ends (21) of the two connectors (2) fit together. Flanges (3) or hot-melt butt welding are used to connect the two connectors (2) at the stepped part. Several holes (4) are opened on the composite pipe (1) at the connector (2). The tensile column (6) of the connector is inside the hole (4).

2. The connector structure for composite pipes of DN110-1200 according to claim 1, characterized in that, The inner and outer layers of the composite pipe (1) are made of PE, PERT, PPR or PP, and the reinforcing layer is made of glass fiber, carbon fiber, aramid fiber or basalt fiber.

3. A connector structure suitable for composite pipes of DN110-1200 according to claim 2, characterized in that, The thickness of each layer of the composite pipe (1) is determined according to the pipe diameter, with the outer layer thickness being 3.0-15.0 mm, the inner layer thickness being 3.2-30.0 mm, and the reinforcing layer thickness being 2.0-10.0 mm.

4. A connector structure suitable for composite pipes of DN110-1200 according to claim 1, characterized in that, The outer layer of the connector (2) and the composite pipe (1) is connected for 100-500mm, the oxide layer is removed, and the inner layer is peeled off for 1.6-500mm.

5. A connector structure suitable for composite pipes of DN110-1200 according to claim 4, characterized in that, The thickness A of the connector (2) is determined according to the pressure level: 80-150mm for high pressure 10.0MPa, 20-42mm for medium pressure 6.4MPa, and 2.0-4.2mm for low pressure 1.6MPa.

6. A connector structure suitable for composite pipes of DN110-1200 according to claim 1, characterized in that, The diameter of the holes (4) is 10-115 mm, and the number is 7-73. The diameter and number are determined according to the diameter of the composite pipe (1).

7. A connector structure suitable for composite pipes of DN110-1200 according to claim 1, characterized in that, The flange (3) has an L-shaped cross section. The inner wall of the flange (31) is tightly attached to the small end (22) of the connector (2). Several screw holes are opened on the vertical surface of the flange (31). The two flanges (31) are connected and fixed by connecting screws (32).

8. A connector structure suitable for composite pipes of DN110-1200 according to claim 1, characterized in that, A water-stop ring (5) is also provided between the two composite pipe sections (1).

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