High-pressure-resistant PFA corrugated pipe

Abstract

The utility model discloses a high-pressure-resistant PFA corrugated pipe, and belongs to the technical field of corrugated pipes. The corrugated pipe solves the problems that an existing connecting mode is low in strength, prone to deformation and inconvenient to disassemble. The scheme comprises a first corrugated pipe and a second corrugated pipe which are respectively provided with a butt joint; the connecting pipe comprises an inner ring and an outer ring; two ends of the inner ring are conical; the fixing ring comprises a connecting ring, and the inner wall is conical. And the fixing ring is in threaded connection with the connecting pipe, so that the conical surface is matched and clamps the butt joint. The pressure resistance of the corrugated pipe is improved, and the corrugated pipe is convenient to mount and dismount. The method is mainly used for pipeline systems in the fields of semiconductors and chemical engineering. A conical matching surface and threads are adopted for meshing in shape, and a radial clamping mechanism for the joint is added in structure.

Description

Technical Field

[0001] This utility model relates to the field of corrugated pipe technology, and in particular to a high-pressure resistant PFA corrugated pipe. Background Technology

[0002] High-pressure PFA bellows are widely used in semiconductor manufacturing, chemical production, aerospace, pharmaceuticals, and the automotive industry. These bellows are typically made of perfluoroalkoxy resin. Currently used bellows are connected using a sleeve-fit adhesive method. This method results in insufficient connection strength, making the bellows prone to deformation. Furthermore, disassembly is difficult, impacting maintenance efficiency. Utility Model Content

[0003] The purpose of this invention is to solve the problems of existing technology where corrugated pipes are connected by a sleeve-fitting adhesive method, which not only has low connection strength and is prone to deformation, but also makes it inconvenient to disassemble later. Therefore, a high-pressure resistant PFA corrugated pipe is proposed.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] A high-pressure resistant PFA corrugated pipe includes: a first corrugated pipe and a second corrugated pipe, both of which have an integrally formed butt joint at their close ends, and a connecting pipe is provided between the first corrugated pipe and the second corrugated pipe. Both sides of the connecting pipe are fitted with fixing rings, and the two fixing rings are respectively sleeved on the outer walls of the two butt joints.

[0006] The connecting pipe includes an inner ring and two outer rings. The outer walls at both ends of the inner ring are tapered, and a groove is formed between the inner ring and the outer rings. The connector is inserted into the groove.

[0007] The fixing ring includes a connecting ring, and the inner wall of the connecting ring is a conical inner wall;

[0008] The outer ring has a first threaded section on its inner wall and a second threaded section on its outer wall. The fixing ring and the connecting pipe are threaded together through the first threaded section and the second threaded section, so that the conical inner wall of the connecting ring and the conical outer wall of the inner ring form a wedge-shaped mating surface, which generates a radial clamping force on the connector.

[0009] In one possible design, the connecting tube further includes a first nut, which is fixedly sleeved on the outer wall of the inner ring, and both sides of the first nut are respectively fixedly connected to the two outer rings.

[0010] In one possible design, the retaining ring further includes a second nut, which is fixedly connected to the connecting ring, and a relief ring is fixed to the inner wall of the second nut.

[0011] In one possible design, the first corrugated pipe and the second corrugated pipe have the same structure, and the first corrugated pipe consists of a leak-proof layer, a reinforcing layer and a base layer from the outside to the inside.

[0012] In one possible design, reinforcing ribs, which are metal wires, are interspersed within the reinforcing layer and are evenly distributed in a ring around the circumference of the first corrugated pipe.

[0013] In one possible design, the cone angle of both the tapered outer wall of the inner ring and the tapered inner wall of the connecting ring is 15°.

[0014] In this application, two fixing rings are respectively fitted onto the mating heads of the first and second corrugated pipes at their closest ends. The two mating heads are respectively inserted into the slots between the outer and inner rings. By using a wrench to put on the second nut and the first nut respectively, the fixing rings are rotated. The fixing rings are threadedly connected through the second threaded section of the outer wall of the connecting ring and the first threaded section of the inner wall of the outer ring, so that the inner wall of the connecting ring and the outer wall of the inner ring fit together to clamp the mating heads. Reinforcing ribs are provided in the reinforcing layer of the first corrugated pipe to enhance the pressure and strength that the two sets of corrugated pipes can withstand. The base layer is waterproofed.

[0015] Beneficial effects: In this utility model, the high-pressure resistant PFA bellows forms a wedge-shaped mating surface with the conical outer wall of the inner ring and the conical inner wall of the connecting ring in the connecting pipe assembly. The first threaded section of the inner wall of the outer ring and the second threaded section of the outer wall of the connecting ring engage with each other, thus constructing a dual guarantee mechanism of mechanical clamping and conical surface sealing. When the fixed ring assembly rotates, the thread preload drives the connecting ring to move axially. Its conical inner wall and the conical outer wall of the inner ring generate radial compression, so that the connecting end face of the butt joint forms a line contact seal. At the same time, the groove formed by the outer ring and the inner ring forms an annular wrap around the butt joint, effectively dispersing the axial tensile stress generated by the internal pressure of the pipeline, improving the pressure resistance of the bellows, and achieving zero leakage sealing.

[0016] In this invention, a high-pressure-resistant PFA corrugated pipe can be connected and assembled without special tools via a second nut and a first nut. Operators only need a standard wrench to operate the second nut and the first nut to tighten the retaining ring and connecting pipe, making it particularly suitable for confined spaces or maintenance scenarios requiring frequent disassembly and assembly.

[0017] In this invention, the connection between the two fixing rings and the connecting pipe not only ensures the sealing of the connection between the first corrugated pipe and the second corrugated pipe, but also ensures the connection strength while enabling quick installation or disassembly between the first corrugated pipe and the second corrugated pipe, making the connection method more convenient and efficient. Attached Figure Description

[0018] Figure 1This is a schematic diagram of a high-pressure-resistant PFA corrugated pipe structure proposed in this utility model;

[0019] Figure 2 This is a cross-sectional exploded view of the high-pressure resistant PFA corrugated pipe connecting pipe and fixing ring proposed in this utility model.

[0020] Figure 3 This is a cross-sectional view of the first corrugated pipe of a high-pressure-resistant PFA corrugated pipe proposed in this utility model.

[0021] In the diagram: 1. First corrugated pipe; 2. Second corrugated pipe; 3. Connecting pipe; 4. Fixing ring; 5. Outer ring; 6. First nut; 7. Inner ring; 8. Second nut; 9. Second threaded section; 10. Leaving ring; 11. Connecting ring; 12. Butt joint; 13. Leak-proof layer; 14. Reinforcing layer; 15. Base layer. Detailed Implementation

[0022] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments.

[0023] In one embodiment: Refer to Figure 1 and Figure 3 A corrugated pipe, the main body of which consists of a first corrugated pipe 1 and a second corrugated pipe 2, both of which have identical structures and adopt a three-layer composite structure design. The outermost layer is a leak-proof layer 13, made of PFA material by extrusion molding, with a continuous corrugated pleated structure on the surface; the middle layer is a reinforcing layer 14, which uses a high-strength glass fiber woven mesh embedded in the PFA substrate. The woven mesh is arranged at a 45-degree angle along the pipe axis, with a weaving density of 80 meshes per centimeter. 304 stainless steel wire with a diameter of 0.5 mm is inserted inside the woven mesh as reinforcing ribs. A total of 12 reinforcing ribs are arranged in a ring evenly distributed in a single corrugated pipe; the innermost layer is a base layer 15, made of modified PTFE material by isostatic pressing molding, with the inner wall roughness controlled below Ra0.4μm.

[0024] Reference Figure 2Both corrugated pipes have an integrally formed butt joint 12 at their joint ends. The outer diameter of the butt joint 12 is 2 mm smaller than that of the corrugated pipe body, and the end is chamfered to form a 30-degree guide slope. The connecting pipe 3 consists of a first nut 6, two outer rings 5, and an inner ring 7. The inner ring 7 is injection molded from PEEK material, and the two sides of the outer wall are machined into 15-degree tapered surfaces. The tapered surfaces are hard chrome plated, and the roughness is controlled to Ra0.2μm. The outer rings 5 ​​are machined from brass, and the inner wall is provided with a standard M20×1.5 thread section with an effective thread engagement length of 12 mm. The first nut 6 is fixedly connected to the inner ring 7 by laser welding. The weld penetration is controlled to 1.2 mm, and the weld strength reaches 350 N·mm.

[0025] Reference Figure 2 The retaining ring 4 consists of a second nut 8 and a connecting ring 11. The second nut 8 is machined from 304 stainless steel with knurling on the outer wall to a depth of 0.3 mm. The inner wall of the connecting ring 11 is machined into a 15-degree tapered hole, and the surface of the tapered hole is titanium-plated to achieve a hardness of HV800. The outer wall of the connecting ring 11 is provided with an M20×1.5 thread section 9 with a thread profile angle of 60 degrees, which forms an interference fit with the inner thread of the outer ring 5, with the interference amount controlled within the range of 0.05-0.1 mm.

[0026] In another embodiment: Reference Figures 1 to 3 A high-pressure-resistant PFA bellows is assembled by fitting two fixing rings 4 onto the connectors 12 of the first bellows 1 and the second bellows 2, respectively, aligning the guide slope of the connector 12 with the tapered hole of the connecting ring 11. The connecting pipe 3 is placed between the two connectors 12, inserting them into the annular grooves formed by the outer ring 5 and the inner ring 7. The groove width is designed to be 3 mm to accommodate the axial displacement of the connectors 12. An open-end wrench is used to simultaneously clamp the second nut 8 and the first nut 6, tightening them clockwise synchronously with a torque controlled at 15 N·m. Under the preload of the thread, the connecting ring 11 moves axially towards the inner ring 7, its tapered inner wall forming a surface contact with the tapered outer wall of the inner ring 7. The contact pressure is converted into radial clamping force through the thread helix angle, causing a 0.15 mm elastic deformation on the surface of the connector 12, forming a line contact sealing band.

[0027] The accompanying drawings in this application are for illustrative purposes only. The dimensions and shapes of the components shown are not actual limitations but are merely schematic representations. In actual implementation, the components can be reasonably configured and adjusted according to specific needs and actual conditions.

[0028] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. A high-pressure resistant PFA corrugated pipe, characterized in that, include: The first corrugated pipe (1) and the second corrugated pipe (2) are integrally formed with a butt joint (12) at their close ends. A connecting pipe (3) is provided between the first corrugated pipe (1) and the second corrugated pipe (2). Fixing rings (4) are connected to both sides of the connecting pipe (3). The two fixing rings (4) are respectively sleeved on the outer walls of the two butt joints (12). The connecting pipe (3) includes an inner ring (7) and two outer rings (5). The outer walls of both ends of the inner ring (7) are tapered. A slot is formed between the inner ring (7) and the outer rings (5). The connector (12) is inserted into the slot. The fixing ring (4) includes a connecting ring (11), the inner wall of which is a conical inner wall; The outer ring (5) has a first threaded section on its inner wall and the connecting ring (11) has a second threaded section (9) on its outer wall. The fixing ring (4) and the connecting pipe (3) are connected by the first threaded section and the second threaded section (9), so that the conical inner wall of the connecting ring (11) and the conical outer wall of the inner ring (7) form a wedge-shaped mating surface, which generates a radial clamping force on the butt joint (12).

2. The high-pressure-resistant PFA corrugated pipe according to claim 1, characterized in that, The connecting tube (3) also includes a first nut (6), which is fixedly sleeved on the outer wall of the inner ring (7), and the two sides of the first nut (6) are respectively fixedly connected to the two outer rings (5).

3. The high-pressure resistant PFA corrugated pipe according to claim 1 or 2, characterized in that, The fixing ring (4) also includes a second nut (8), which is fixedly connected to the connecting ring (11), and a relief ring (10) is fixed on the inner wall of the second nut (8).

4. The high-pressure resistant PFA corrugated pipe according to claim 1, characterized in that, The first corrugated pipe (1) and the second corrugated pipe (2) have the same structure. The first corrugated pipe (1) consists of a leak-proof layer (13), a reinforcing layer (14) and a base layer (15) from the outside to the inside.

5. The high-pressure resistant PFA corrugated pipe according to claim 4, characterized in that, The reinforcing layer (14) is interspersed with reinforcing ribs, which are metal wires and are evenly distributed in a ring around the circumference of the first corrugated pipe (1).

6. The high-pressure resistant PFA corrugated pipe according to claim 5, characterized in that, The cone angle of the conical outer wall of the inner ring (7) and the conical inner wall of the connecting ring (11) is 15°.

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