High strength polytetrafluoroethylene composite tube

Abstract

The utility model relates to the technical field of composite pipe, specifically disclose a kind of high-strength polytetrafluoroethylene composite pipe, comprising: pipe body, the metal braided reinforcing layer is arranged in the pipe body, the inner core is uniformly provided at the both ends of pipe body, the inner core is tubularly arranged, the outer lateral wall of the inner core is fixedly provided with multiple inverted toothing, multiple the inverted toothing is equidistant annular arrangement and is provided on the outer lateral wall of the inner core, the inverted toothing is embedded in the inner lateral wall of pipe body and is provided, two the inner core opposite end is uniformly provided with connecting assembly, the outer portion of pipe body is equipped with protection assembly;The utility model is embedded in the cooperation of the inverted toothing structure of the outer lateral wall of the inner core and the inner lateral wall of pipe body, and the abutting contact of shoulder and the outer side of pipe body, forms the double guarantee of mechanical interlocking and end face sealing, greatly enhances the reliability and anti-pulling ability of terminal connection, and the synergistic effect of outer sleeve and metal braided connection layer by compression ring, ensure long-term safe and stable operation under extreme working conditions.

Description

Technical Field

[0001] This utility model belongs to the field of composite pipe technology, specifically relating to a high-strength polytetrafluoroethylene composite pipe. Background Technology

[0002] Polytetrafluoroethylene (PTFE) composite pipe is a type of pipe made by using high-performance engineering plastic PTFE as the inner lining and wrapping a metal braided reinforcement layer on the outer layer through a special composite process. Its fundamental function is to solve the problem of fluid transportation under extreme working conditions. It perfectly inherits the excellent chemical stability, extremely low coefficient of friction and wide temperature resistance of PTFE itself, and can withstand the erosion of most corrosive media such as strong acids, strong alkalis and strong solvents, ensuring the high purity of the fluid.

[0003] Meanwhile, its outer metal braided reinforcement layer, like a robust cage structure, effectively overcomes the fatal weaknesses of pure PTFE pipes, such as low mechanical strength, easy creep, and poor pressure resistance. This endows the composite pipe with extremely high pressure resistance, excellent tensile strength, and outstanding resistance to negative pressure vacuum, thus becoming an ultimate pipeline solution that can simultaneously cope with high temperature, high pressure, high corrosion, and high vacuum environments. It is widely used in fields with extremely high requirements for safety and reliability, such as semiconductor manufacturing, chemical industry, pharmaceutical equipment, and aerospace.

[0004] The sealing and fixing effects of existing composite pipe end fittings are poor. Traditional compression fittings or clamp fittings can only clamp the outer metal braided layer of the pipe, but cannot effectively restrain the internal PTFE liner. The smooth PTFE surface has an extremely low coefficient of friction. Under the action of internal fluid pressure, the PTFE liner can easily be "pulled out" from the clamped metal braided layer, causing leakage at the connection or even pipe end detachment. In addition, traditional fittings have poor sealing effect under negative pressure conditions, posing a risk of leakage. Utility Model Content

[0005] The purpose of this invention is to provide a high-strength polytetrafluoroethylene composite pipe to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, this utility model provides the following technical solution:

[0007] A high-strength polytetrafluoroethylene composite pipe includes: a pipe body, an inner metal braided reinforcement layer, inner cores at both ends of the pipe body, the inner cores being tubular, a plurality of reverse teeth fixedly arranged on the outer wall of the inner cores, the plurality of reverse teeth being arranged in an equidistant ring on the outer wall of the inner cores, the reverse teeth being embedded in the inner wall of the pipe body, a connecting component being provided at opposite ends of the two inner cores, and a protective component being provided on the outside of the pipe body.

[0008] Preferably, the connecting assembly includes a shoulder fixedly disposed on the outer wall of the inner core, the outer wall of the shoulder abutting against the outer wall of the tube body, a connector fixedly disposed at the end of the shoulder away from the inner core, the connector being tubular and having external threads on the outside, and a fixing assembly disposed on the outside of the inner core.

[0009] Preferably, the fixing component includes an outer sleeve fixedly fitted onto the outer wall of the tube body, the outer sleeve being disposed at the end of the tube body, and a metal braided connecting layer being disposed between the outer sleeve and the tube body.

[0010] Preferably, the inner sidewall of the outer casing has an installation groove, the installation groove is annular, and a clamping ring is provided inside the installation groove, the clamping ring being located at the end of the tube body.

[0011] Preferably, the protective component includes a protective sleeve disposed on the outer wall of the pipe body, the outer wall of the protective sleeve having multiple fixing grooves, and the inner wall of the fixing grooves being fixedly provided with reinforcing ribs.

[0012] Preferably, a sound-absorbing and heat-insulating layer is fixedly provided on the inner wall of the protective sleeve, and the sound-absorbing and heat-insulating layer is fixedly sleeved on the pipe body.

[0013] Compared with the prior art, the beneficial effects of this utility model are:

[0014] The toothed structure on the outer wall of the inner core and the embedded fit with the inner wall of the tube, combined with the tight contact between the shoulder and the outer side of the tube, form a dual guarantee of mechanical interlocking and end face sealing. This greatly enhances the reliability and pull-out resistance of the terminal connection, avoiding the easy pushing out or separation of the PTFE liner by fluid pressure in traditional joints. The outer sleeve, through the synergistic effect of the compression ring and the metal braided connection layer, tightly compresses all parts of the tube end into a rigid whole, significantly improving the pressure resistance, pulse fatigue resistance and negative pressure sealing performance at the joint, ensuring long-term safe and stable operation under extreme working conditions. The external protective components provide mechanical protection while also having sound absorption and heat insulation functions, further expanding the applicable environment of the composite pipe. Attached Figure Description

[0015] Figure 1 This is a perspective view of the present utility model;

[0016] Figure 2 This is a schematic diagram of the connection structure between the tube body and the outer sleeve of this utility model;

[0017] Figure 3 This is a cross-sectional view of the connection structure between the inner core and the connector in this utility model;

[0018] Figure 4 This is a schematic diagram of the inner core and tube body in this utility model;

[0019] Figure 5This is a schematic diagram of the protective component in this utility model;

[0020] In the diagram: 1. Pipe body; 2. Metal braided reinforcement layer; 3. Inner core; 4. Back teeth; 5. Shoulder; 6. Connector; 7. External thread; 8. Outer jacket; 9. Metal braided connecting layer; 10. Compression ring; 11. Protective sleeve; 12. Reinforcing rib; 13. Sound-absorbing and heat-insulating layer. Detailed Implementation

[0021] 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.

[0022] Example 1:

[0023] Please see Figure 1 - Figure 5 As shown, a high-strength polytetrafluoroethylene composite pipe includes: a pipe body 1, a metal braided reinforcement layer 2 inside the pipe body 1, an inner core 3 at both ends of the pipe body 1, the inner core 3 being tubular, a plurality of inverted teeth 4 being fixedly provided on the outer wall of the inner core 3, the plurality of inverted teeth 4 being arranged in an equidistant ring on the outer wall of the inner core 3, the inverted teeth 4 being embedded in the inner wall of the pipe body 1, a connecting component being provided at one of the opposite ends of the two inner cores 3, and a protective component being provided on the outside of the pipe body 1.

[0024] As can be seen from the above, through the synergistic effect between the connecting assembly consisting of shoulder 5, connector 6, and external thread 7 and the connecting assembly consisting of outer sleeve 8, metal braided connecting layer 9, and clamping ring 10, mechanical interlocking, end face sealing and overall reinforcement of the pipe body 1 terminal connection are achieved. The protective assembly consisting of protective sleeve 11, reinforcing rib 12, and sound-absorbing and heat-insulating layer 13 provides multi-functional external protection for the pipe body 1.

[0025] During crimping, the inner core 3 is first inserted into the tube body 1, the metal braided connecting layer 9 is placed on the end of the tube body 1, the clamping ring 10 is placed into the mounting groove, and then the outer sleeve 8 with the annular mounting groove is placed on the metal braided connecting layer 9. The six-lobed mold is used to apply radial pressure from the outside to the inside. The clamping ring 10 instantly bites through the metal braided connecting layer 9 and is snapped into the surface of the tube body 1 together with the outer sleeve 8. At the same time, during the crimping process, the PTFE liner is squeezed by the inverted teeth 4. When the local stress exceeds its yield strength, the material will "cold flow" at room temperature and slowly squeeze into the recessed area between the tooth root and the tooth tip along the tooth side gap. When the external force is removed and the temperature returns to room temperature, the PTFE molecular chain recrystallizes and is "stuck" on the back side of the inverted teeth 4, forming a plastic protrusion that fits the tooth shape perfectly. This creates an irreversible mechanical lock between the tube body 1 and the inner core 3, thereby significantly enhancing the pull-out resistance and ensuring the long-term effectiveness of the end face seal.

[0026] The shoulder 5 end face is tightly attached to the tube body 1 end face, forming a second end face seal and axial pull-out resistance structure, continuously maintaining axial pressure, so that the outer sleeve 8, clamping ring 10, metal braided connecting layer 9, tube body 1 and inner core 3 and shoulder 5 are nested in size and pressed against each other in stress, and finally solidified into a rigid whole that can withstand high pressure, pulse and negative pressure, completing the entire crimping process.

[0027] Specifically, regarding the above-mentioned connecting components, the connecting components include a shoulder 5 fixedly disposed on the outer wall of the inner core 3, the outer wall of the shoulder 5 and the outer wall of the tube 1 in close contact, a connector 6 fixedly disposed at the end of the shoulder 5 away from the inner core 3, the connector 6 being tubular and having external threads 7 on the outside, and a fixing component being disposed on the outside of the inner core 3.

[0028] The fixing component includes an outer sleeve 8 that is fixedly fitted onto the outer wall of the tube body 1. The outer sleeve 8 is disposed at the end of the tube body 1, and a metal braided connecting layer 9 is provided between the outer sleeve 8 and the tube body 1.

[0029] The inner wall of the outer casing 8 is provided with an installation groove, which is arranged in a ring shape. A clamping ring 10 is provided inside the installation groove, and the clamping ring 10 is located at the end of the tube body 1.

[0030] As can be seen from the above, during assembly, the inner core 3 is pressed into the polytetrafluoroethylene liner at the end of the tube body 1 by multiple reverse teeth 4 arranged in a ring at equal intervals on its outer side wall in an interference fit. The wedge-shaped structure of the reverse teeth 4 will cause slight plastic deformation of the PTFE material during the pressing process and fill the gap between the teeth. After cooling and shaping, a firm mechanical interlock is formed. Its directional design can effectively resist the axial pull-out force from the fluid pressure inside the tube, avoid easy pull-out between the tube body 1 and the inner core 3, and make the connector 6 stably set at the end of the tube body 1.

[0031] After the shoulder 5 on the inner core 3 is assembled, its outer wall forms a tight contact with the outer wall of the end face of the pipe body 1, preventing the fluid from leaking outward along the pipe wall. The external thread 7 on the connector 6 provides a standard and reliable connection interface with the external pipeline system. To further improve the overall integrity, the pressing process makes the outer jacket 8, the metal braided connecting layer 9, the compression ring 10, the pipe body 1 and the inner core 3 form a rigid whole, which improves the pressure resistance, pulse fatigue resistance and negative pressure sealing performance of the joint, ensuring long-term safe and stable operation under extreme working conditions.

[0032] Example 2:

[0033] Specifically, regarding the aforementioned protective components, the protective components include a protective sleeve 11 disposed on the outer wall of the pipe body 1. The outer wall of the protective sleeve 11 has multiple fixing grooves, and the inner wall of the fixing grooves is fixedly provided with reinforcing ribs 12.

[0034] A sound-absorbing and heat-insulating layer 13 is fixedly installed on the inner wall of the protective sleeve 11, and the sound-absorbing and heat-insulating layer 13 is fixedly sleeved on the pipe body 1.

[0035] As can be seen from the above, the sound-absorbing and heat-insulating layer 13 is directly and tightly wrapped on the outer wall of the pipe body 1. This layer is usually made of high-temperature resistant glass wool, rock wool or ceramic fiber and other materials. It can effectively block the heat exchange between the high-temperature or low-temperature fluid in the pipe body 1 and the external environment, reduce energy loss, and absorb the vibration noise generated by the fluid flow and pressure pulse in the pipe, thus improving the working environment.

[0036] The outer protective sleeve 11 mainly serves a mechanical protection function. It is made of wear-resistant and impact-resistant polymers (such as polyurethane) or metal materials to prevent the tube body 1 from being scratched, impacted, or worn during installation and use. The multiple fixing grooves on the outer wall of the protective sleeve 11 and the reinforcing ribs 12 embedded inside significantly enhance the structural rigidity and bending resistance of the protective sleeve 11 itself, enabling it to withstand certain external loads. The reinforcing ribs 12 are usually made of metal or high-strength engineering plastics. The entire protective assembly provides physical protection while also taking into account heat preservation and noise reduction, greatly expanding the application potential of this composite tube in sensitive environments (such as equipment areas that need to maintain temperature or require a quiet environment).

[0037] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A high-strength polytetrafluoroethylene composite pipe, characterized in that, include: The tube (1) has a metal braided reinforcement layer (2) inside. Both ends of the tube (1) are provided with inner cores (3). The inner cores (3) are tubular. Multiple inverted teeth (4) are fixedly provided on the outer wall of the inner cores (3). The multiple inverted teeth (4) are arranged in an equidistant ring on the outer wall of the inner cores (3). The inverted teeth (4) are embedded in the inner wall of the tube (1). A connecting component is provided at one opposite end of the two inner cores (3). A protective component is provided on the outside of the tube (1).

2. The high-strength polytetrafluoroethylene composite pipe according to claim 1, characterized in that: The connecting assembly includes a shoulder (5) fixedly disposed on the outer wall of the inner core (3), the outer wall of the shoulder (5) and the outer wall of the tube (1) are in close contact, a connector (6) is fixedly disposed at the end of the shoulder (5) away from the inner core (3), the connector (6) is tubular and has an external thread (7), and a fixing assembly is disposed on the outside of the inner core (3).

3. The high-strength polytetrafluoroethylene composite pipe according to claim 2, characterized in that: The fixing component includes an outer sleeve (8) fixedly fitted onto the outer wall of the tube body (1), the outer sleeve (8) being disposed at the end of the tube body (1), and a metal braided connecting layer (9) being disposed between the outer sleeve (8) and the tube body (1).

4. The high-strength polytetrafluoroethylene composite pipe according to claim 3, characterized in that: The inner wall of the outer casing (8) is provided with an installation groove, which is arranged in a ring shape. A clamping ring (10) is provided inside the installation groove, and the clamping ring (10) is located at the end of the tube body (1).

5. A high-strength polytetrafluoroethylene composite pipe according to claim 1, characterized in that: The protective component includes a protective sleeve (11) disposed on the outer wall of the tube body (1). The outer wall of the protective sleeve (11) has multiple fixing grooves, and the inner wall of the fixing grooves is fixedly provided with reinforcing ribs (12).

6. A high-strength polytetrafluoroethylene composite pipe according to claim 5, characterized in that: The inner wall of the protective sleeve (11) is fixedly provided with a sound-absorbing and heat-insulating layer (13), which is fixedly sleeved on the tube body (1).

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