High strength wound fluoropolymer lined pipe

Abstract

The application discloses a high-strength winding fluorine-lined pipeline, which comprises a pipeline shell and a fluorine inner lining pipe, and the fluorine inner lining pipe is fixedly sleeved on the inner side of the pipeline shell. The application adds a winding metal ring to generate horizontal supporting force on the pipeline shell and the fluorine inner lining pipe, so that the connecting strength of the pipeline shell and the fluorine inner lining pipe is guaranteed. When two pipeline shells are connected with each other, the arc-shaped blocks at the end portions slide into short arc-shaped grooves along the slideways, and the short arc-shaped grooves horizontally limit the arc-shaped blocks, so that the pipeline connection is not only dependent on the fixing of bolts, and the fixing strength of the connection position is higher. In the application, carbon black is added during the manufacturing of the fluorine inner lining pipe, the carbon black improves the wear resistance of the material, the quartz sand is subjected to pickling and chlorination treatment, the influence of impurities in the quartz sand on the material is reduced, and the thermoplastic polyurethane is added in the base material, so that the elasticity and flexibility of the lining material are increased, and the lining is difficult to be damaged even if it is subjected to the fluid impact of a large force.

Description

Technical Field

[0001] This invention relates to the field of fluoropolymer-lined pipe technology, specifically to a high-strength spiral-wound fluoropolymer-lined pipe. Background Technology

[0002] Fluorine-lined pipes possess excellent temperature and corrosion resistance, making them ideal for conveying highly corrosive media such as nitric acid, sulfuric acid, hydrofluoric acid, phosgene, chlorine, aqua regia, mixed acids, bromides, and other organic solvents. They are widely used in chemical, oil refining, light industry, and metallurgical sectors. They are manufactured by fitting a fluoroplastic-lined tube inside a pipe made of steel or other materials. In the first method, the inner lining tube is directly inserted into the steel pipe, and then the ends are flanged. This connection relies primarily on the flanged structure at both ends, resulting in poor strength. Therefore, an alternative manufacturing method has emerged: the inner lining tube, with an outer diameter slightly larger than the inner diameter of the steel pipe, is forcibly pulled into the steel pipe to form a tight, gapless lining. This is then placed in a furnace for constant temperature adaptation. However, this method still has the following drawbacks in connection strength:

[0003] This type of connection creates a tight, gapless lining between the lining and the steel pipe. However, it lacks good compensation for thermal expansion and contraction, resulting in gaps that affect the connection strength. Furthermore, when fluoropolymer-lined pipes are connected to each other, flange bolts are mainly used, and the connection force relies primarily on the bolts. These bolts are prone to wear, affecting the connection strength. Additionally, the fluoropolymer lining relies mainly on the quartz sand added during manufacturing to ensure wear resistance. However, quartz sand contains many impurities, which affects the wear resistance of the fluoropolymer lining. Moreover, the fluoropolymer lining lacks flexibility and is easily damaged when subjected to strong impacts from the fluid medium.

[0004] Therefore, we propose a high-strength spiral wound fluoropolymer-lined pipe to solve the above problems. Summary of the Invention

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

[0006] To achieve the above objectives, the present invention provides the following technical solution: a high-strength spiral-wound fluoropolymer-lined pipe, comprising a pipe shell and a fluoropolymer liner, wherein the fluoropolymer liner is fixedly sleeved inside the pipe shell, and multiple inner grooves are uniformly formed on the inner side of the pipe shell; multiple outer grooves are formed on the outer wall of the fluoropolymer liner at the same vertical position corresponding to the multiple inner grooves; a spiral metal ring is fixedly sleeved inside the outer groove, and the outer side of the spiral metal ring is sleeved inside the inner groove; a spiral iron wire is fixedly embedded inside the fluoropolymer liner, and multiple horizontal iron wires are horizontally fixedly connected to the spiral iron wire;

[0007] An inner annular groove is formed on the inner side of one end of the pipe shell, and an outer shell extension tube is fixedly connected to the other end of the pipe shell. The outer shell extension tube and the pipe shell are an integral structure. The inner diameter of the outer shell extension tube is the same as the inner diameter of the pipe shell, and the outer diameter of the outer shell extension tube is the same as the inner diameter of the inner annular groove. Four slides are evenly and horizontally formed on the inner side of the inner annular groove. One end of the slide is an open structure, and the other end is a closed structure. A short arc groove is formed at the closed end of the inner annular groove. The short arc groove is connected to the slide. Four arc-shaped blocks are evenly fixed to the periphery of the outer shell extension tube away from the pipe shell. The length of the arc block is the same as the width of the slide, and the width is the same as the width of the short arc groove.

[0008] Preferably, an outer ring groove is formed on the outer side of one end of the fluoropolymer liner at the same vertical position as the inner ring groove. A first inner liner extension tube is fixed to the end of the fluoropolymer liner near the outer ring groove. The first inner liner extension tube and the fluoropolymer liner are an integral structure. The thickness of the end of the first inner liner extension tube away from the fluoropolymer liner is lower than the thickness of the other end.

[0009] Preferably, an arc-shaped groove is formed on the inner side of the end of the fluoropolymer liner tube away from the first liner extension tube, and a second liner extension tube is fixedly connected to the end of the fluoropolymer liner tube away from the first liner extension tube. The second liner extension tube and the fluoropolymer liner tube are an integral structure.

[0010] Preferably, the shape and size of the arc-shaped annular groove are consistent with those of the first inner lining extension tube, the outer diameter of the second inner lining extension tube is consistent with the outer diameter of the fluorine inner lining tube, and the inner diameter of the second inner lining extension tube is consistent with the outer diameter of the outer annular groove.

[0011] Preferably, a first flange is fixedly sleeved on the periphery of the pipe shell near the inner ring groove, a first fluoroplastic ring is fixedly connected to the side of the first flange away from the pipe shell, and a convex ring is fixedly connected to the side of the first fluoroplastic ring away from the first flange. The convex ring and the first fluoroplastic ring are integral structures, and multiple first through holes are uniformly and horizontally opened on the first fluoroplastic ring and the first flange.

[0012] Preferably, a second flange is fixedly sleeved on the periphery of the end of the pipe shell away from the first flange, and a second fluoroplastic ring is fixedly connected to the side of the second flange away from the pipe shell. A concave annular groove is formed on the side of the second fluoroplastic ring away from the second flange, and the shape and size of the concave annular groove are the same as those of the convex annular groove. Multiple second through holes are horizontally formed on the second fluoroplastic ring and the second flange. Multiple filling holes are formed at the end of the pipe shell directly above the four slides. The filling holes are connected to the slides, and the ends of the filling holes are fitted with plugs.

[0013] Preferably, the preparation steps of the fluorine-lined tube are as follows:

[0014] Step 1: Ingredients: Prepare one part of perfluoroethylene propylene, one part of carbon black, one part of quartz sand, one part of thermoplastic polyurethane, one part of bentonite, one part of short glass fiber, one part of coupling agent, one part of lubricant, and one part of plasticizer.

[0015] Step 2: Mixing: Place polytetrafluoroethylene propylene, carbon black, thermoplastic polyurethane and lubricant into a mixer in sequence, heat to -℃ and mix for -min to obtain the mixed mixture.

[0016] Step 3: Quartz Sand Treatment: The quartz sand is soaked in hydrochloric acid and hydrofluoric acid in sequence. After soaking, it is washed with water, dried, and then placed in a vacuum environment for chlorination treatment. The temperature is maintained at -℃. Under the action of chlorine gas, the alkali metal and alkaline earth metal impurities in the quartz sand are converted into gaseous chlorides. The chlorination treatment removes the alkali metal and alkaline earth metal impurities in the quartz sand and the impurities on the surface of the quartz sand particles, resulting in high-purity quartz sand.

[0017] Step 4: Internal mixing: Add the mixture obtained in Step 2 and the high-purity quartz sand obtained in Step 2 into the internal mixer, then add bentonite, short glass fiber, coupling agent and plasticizer in sequence, and internal mix for -min at a temperature of -℃ to obtain the internally mixed mixture;

[0018] Step 5: Molding: The mixture obtained in Step 4 is added to a twin-screw extruder and extruded at a temperature of -℃. It is then stamped through a die, cooled and shaped to obtain a fluorine-lined tube.

[0019] Compared with the prior art, the beneficial effects of the present invention are:

[0020] This invention provides horizontal support for both the fluoropolymer liner and the pipe shell when they are connected via an added winding metal ring. The inner groove for securing the winding metal ring also effectively compensates for the thermal expansion and contraction of the fluoropolymer liner. When a gap appears between the pipe shell and the fluoropolymer liner, the winding metal ring will not dislodge from the inner groove, ensuring the connection strength between the pipe shell and the fluoropolymer liner. Furthermore, when two pipe shells are connected, the arc-shaped block at the end slides into a short arc groove along a slide rail. The short arc groove horizontally limits the arc-shaped block, thus eliminating the reliance on bolts for pipe connection. Even if the bolts loosen, the strength of the pipe connection can be guaranteed, and the connection fixation strength is higher. In the manufacturing process of the fluorine liner pipe in this invention, carbon black is added, which improves the wear resistance of the material. The added quartz sand is acid-washed and chlorinated to reduce the impact of impurities in the quartz sand on the material, further ensuring the wear resistance. Impurity-type fluid media will not damage the inner wall of the fluorine liner pipe. The addition of thermoplastic polyurethane to the base material increases the elasticity and flexibility of the liner material, which has a good buffering effect, making the liner difficult to damage even when subjected to large-force fluid impact, thus ensuring the strength of the fluorine liner pipe. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the main structure in the first embodiment of the present invention;

[0022] Figure 2 These are schematic diagrams of the main body cross-section structure in the first and second embodiments of the present invention;

[0023] Figure 3 For the present invention Figure 2 Enlarged structural diagram of point A in the middle;

[0024] Figure 4 For the present invention Figure 2 Enlarged structural diagram of section B in the middle;

[0025] Figure 5 This is a schematic diagram of the cross-sectional structure of the fluorine-lined tube in the second embodiment of the present invention;

[0026] Figure 6 This is a schematic diagram of the connection structure between the two pipe shells in the second embodiment of the present invention;

[0027] Figure 7 This is a cross-sectional view of the connection between the two pipe shells in the second embodiment of the present invention;

[0028] Figure 8 This is a schematic diagram of the slide structure in the second embodiment of the present invention.

[0029] In the diagram: 1. Pipe outer shell; 2. Fluorine liner; 11. Inner groove; 12. First flange; 13. Second flange; 14. Inner annular groove; 15. Slide rail; 16. Short arc groove; 17. Outer shell extension tube; 18. Arc block; 19. First fluoroplastic ring; 110. Convex ring; 111. First through hole; 112. Second fluoroplastic ring; 113. Concave annular groove; 114. Second through hole; 115. Filling hole; 116. Plug; 21. Outer annular groove; 22. First liner extension tube; 23. Arc annular groove; 24. Second liner extension tube; 25. Outer groove; 26. Wound metal ring; 27. Spiral wire; 28. Horizontal wire. Detailed Implementation

[0030] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] Example 1:

[0032] Please see Figure 1-5This invention provides a technical solution: a high-strength spiral-wound fluoropolymer-lined pipe, comprising a pipe shell 1 and a fluoropolymer liner 2. The fluoropolymer liner 2 is fixedly sleeved inside the pipe shell 1. Multiple inner grooves 11 are evenly distributed on the inner side of the pipe shell 1. Multiple outer grooves 25 are formed on the outer wall of the fluoropolymer liner 2 at the same vertical position corresponding to the inner grooves 11. A spiral metal ring 26 is fixedly sleeved inside the outer groove 25, and the outer side of the spiral metal ring 26 is sleeved inside the inner groove 11. A spiral iron wire 27 is fixedly embedded inside the fluoropolymer liner 2. Multiple horizontal wires 28 are horizontally fixed on the spiral wire 27. The spiral wire 27 and the horizontal wires 28 are used to improve the strength of the fluorine liner tube 2. When the fluorine liner tube 2 is connected to the pipe shell 1, a simple sleeve connection is no longer used. The added winding metal ring 26 provides horizontal support for the pipe shell 1 and the fluorine liner tube 2. The inner groove 11 used to fix the winding metal ring 26 also provides better compensation for the thermal expansion and contraction of the fluorine liner tube 2, ensuring the connection strength between the pipe shell 1 and the fluorine liner tube 2.

[0033] An inner annular groove 14 is formed on the inner side of one end of the pipe shell 1, and an outer shell extension pipe 17 is fixedly connected to the other end of the pipe shell 1. The outer shell extension pipe 17 and the pipe shell 1 are integral structures. The inner diameter of the outer shell extension pipe 17 is the same as the inner diameter of the pipe shell 1, and the outer diameter of the outer shell extension pipe 17 is the same as the inner diameter of the inner annular groove 14. Four slides 15 are evenly and horizontally formed on the inner side of the inner annular groove 14. One end of the slide 15 is an open structure, and the other end is a closed structure. A short arc groove 16 is formed at the closed end of the inner annular groove 14. The short arc groove 16 and the slide 15 are connected to the inner annular groove 14. 5. The outer shell extension tube 17 is connected to four arc-shaped blocks 18 evenly fixed to the periphery of the end away from the outer shell 1 of the pipe. The length of the arc-shaped block 18 is the same as the width of the slide 15, and the width is the same as the width of the short arc groove 16. When the two outer shells 1 of the pipe are connected to each other, the arc-shaped block 18 at the end slides into the short arc groove 16 along the slide 15. The short arc groove 16 will horizontally limit the arc-shaped block 18. In this way, the pipe connection does not rely solely on the fixing of bolts. Even if the bolts are loose, the strength of the pipe connection can be guaranteed, and the connection fixing strength is higher.

[0034] Example 2:

[0035] Please see Figure 2-8 This is the second embodiment of the present invention. This embodiment is based on the previous embodiment. An outer ring groove 21 is opened on the outer side of one end of the fluoroliner tube 2 at the same vertical position as the inner ring groove 14. A first inner liner extension tube 22 is fixed to the end of the fluoroliner tube 2 near the outer ring groove 21. The first inner liner extension tube 22 and the fluoroliner tube 2 are an integral structure. The thickness of the end of the first inner liner extension tube 22 away from the fluoroliner tube 2 is lower than the thickness of the other end.

[0036] An arc-shaped annular groove 23 is opened on the inner side of the end of the fluoropolymer liner tube 2 away from the first liner extension tube 22, and the end of the fluoropolymer liner tube 2 away from the first liner extension tube 22 is fixedly connected to the second liner extension tube 24. The second liner extension tube 24 and the fluoropolymer liner tube 2 are an integral structure.

[0037] The arc-shaped annular groove 23 has the same shape and size as the first inner lining extension tube 22, the outer diameter of the second inner lining extension tube 24 has the same outer diameter as the fluorine inner lining tube 2, and the inner diameter of the second inner lining extension tube 24 has the same outer diameter as the outer annular groove 21. When the two pipe shells 1 are connected to each other, the second inner lining extension tube 24 is inserted into the outer annular groove 21, and the first inner lining extension tube 22 is inserted into the arc-shaped annular groove 23. In this way, the splicing position is an irregular bend joint, which is not easy to penetrate.

[0038] A first flange 12 is fixedly sleeved on one side of the pipe shell 1 near the inner ring groove 14. A first fluoroplastic ring 19 is fixedly connected to the side of the first flange 12 away from the pipe shell 1. A convex ring 110 is fixedly connected to the side of the first fluoroplastic ring 19 away from the first flange 12. The convex ring 110 and the first fluoroplastic ring 19 are an integral structure. Multiple first through holes 111 are evenly and horizontally opened on the first fluoroplastic ring 19 and the first flange 12.

[0039] A second flange 13 is fixedly sleeved around the end of the pipe shell 1 away from the first flange 12. A second fluoroplastic ring 112 is fixedly connected to the side of the second flange 13 away from the pipe shell 1. A concave annular groove 113 is opened on the side of the second fluoroplastic ring 112 away from the second flange 13. The shape and size of the concave annular groove 113 are the same as the convex ring 110. Multiple second through holes 114 are horizontally opened on the second fluoroplastic ring 112 and the second flange 13. Multiple filling holes 115 are opened at the end of the pipe shell 1 directly above the four slides 15. The filling holes 115 are connected to the slides 15. The end of the filling hole 115 is fitted with an interference fit plug 116. When the two pipe shells 1 are connected, after the arc block 18 is smoothly inserted into the short arc groove 16, the filling hole 115 can be filled with adhesive to seal the slides 15 and the end of the short arc groove 16, further improving the tightness of the connection.

[0040] Example 3:

[0041] The third embodiment of the present invention, based on the above two embodiments, provides the preparation steps of the fluorine-lined tube 2:

[0042] Step 1: Ingredient preparation: 110-140 parts of polytetrafluoroethylene propylene, 21-34 parts of carbon black, 18-24 parts of quartz sand, 15-18 parts of thermoplastic polyurethane, 12-20 parts of bentonite, 5-8 parts of short glass fiber, 4-7 parts of coupling agent, 2-5 parts of lubricant, and 1-3 parts of plasticizer.

[0043] Step 2: Mixing: Place polytetrafluoroethylene propylene, carbon black, thermoplastic polyurethane and lubricant into a mixer in sequence, heat to 280-300℃ and mix for 13-17 minutes to obtain the mixed mixture.

[0044] Step 3: Quartz Sand Treatment: The quartz sand is soaked in hydrochloric acid and hydrofluoric acid in sequence. After soaking, it is washed with water, dried, and then placed in a vacuum environment for chlorination treatment. The temperature is maintained at 65-75℃. Under the action of chlorine gas, the alkali metal and alkaline earth metal impurities in the quartz sand are converted into gaseous chlorides. The chlorination treatment removes the alkali metal and alkaline earth metal impurities in the quartz sand and the impurities on the surface of the quartz sand particles, resulting in high-purity quartz sand.

[0045] Step 4: Internal mixing: Add the mixture obtained in Step 2 and the high-purity quartz sand obtained in Step 2 into the internal mixer, and then add bentonite, short glass fiber, coupling agent and plasticizer in sequence. Mix at a temperature of 290-310℃ for 30-40 minutes to obtain the internally mixed mixture.

[0046] Step 5: Molding: The intensively mixed mixture obtained in Step 4 is added to a twin-screw extruder and extruded at a temperature of 275-290℃. It is then stamped and shaped through a die, cooled and solidified to obtain the fluoropolymer liner 2. Poly(fluoroethylene propylene) and carbon black are used as base materials. Carbon black improves the wear resistance of the material. The added quartz sand is acid-washed and chlorinated to reduce the impact of impurities in the quartz sand on the material, further ensuring the wear resistance. Impurity-type fluid media will not damage the inner wall of the fluoropolymer liner 2. The addition of thermoplastic polyurethane to the base material increases the elasticity and flexibility of the liner material, providing a good cushioning effect. This makes the liner difficult to damage even when subjected to strong fluid impacts, ensuring the strength of the fluoropolymer liner 2.

[0047] Example 4:

[0048] Please see Figure 1-8This is the fourth embodiment of the present invention, based on the above three embodiments. When the pipe shells 1 are connected, the arc-shaped block 18 is inserted into the slide rail 15. At this time, the shell extension tube 17 and the second inner lining extension tube 24 are inserted into the inner groove 11 and the outer ring groove 21. After being inserted to the bottom, one pipe shell 1 is rotated so that the arc-shaped block 18 is inserted into the short arc groove 16. At this time, the first through hole 111 and the second through hole 114 are aligned and fixed with bolts. Then, glue is filled from the filling hole 115 to seal the end of the slide rail 15 and the short arc groove 16. The end of the filling hole 115 is sealed with the plug 116. When the fluorine lining tube 2 and the pipe shell 1 are connected, the added winding metal ring 26 provides horizontal support for the pipe shell 1 and the fluorine lining tube 2. The inner groove 11 used to fix the winding metal ring 26 also provides better compensation for the thermal expansion and contraction of the fluorine lining tube 2. When a gap appears between the pipe shell 1 and the fluorine lining tube 2, The wound metal ring 26 will not come out of the inner groove 11, ensuring the connection strength between the pipe shell 1 and the fluorine liner 2. When the two pipe shells 1 are connected to each other, the arc-shaped block 18 at the end slides into the short arc groove 16 along the slide 15. The short arc groove 16 will horizontally limit the arc-shaped block 18. In this way, the pipe connection does not rely solely on bolt fixation. Even if the bolts loosen, the strength of the pipe connection can still be guaranteed, and the connection fixation strength is higher. In the manufacturing of the fluorine liner 2, carbon black is added, which improves the wear resistance of the material. The added quartz sand is acid-washed and chlorinated, which reduces the impact of impurities in the quartz sand on the material, further ensuring the wear resistance. Impurity-type fluid media will not damage the inner wall of the fluorine liner 2. The addition of thermoplastic polyurethane to the base material increases the elasticity and flexibility of the liner material, which has a good buffering effect, making the liner difficult to damage even when subjected to large-force fluid impact, thus ensuring the strength of the fluorine liner 2.

[0049] Although embodiments of the 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 invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A high-strength spiral wound fluoropolymer-lined pipe, comprising a pipe outer shell (1) and a fluoropolymer inner lining pipe (2), characterized in that: The fluorine liner tube (2) is fixedly sleeved on the inner side of the pipe shell (1). Multiple inner grooves (11) are evenly opened on the inner side of the pipe shell (1). Multiple outer grooves (25) are opened on the outer side wall of the fluorine liner tube (2) at the same vertical position corresponding to the multiple inner grooves (11). The inner side of the outer groove (25) is fixedly sleeved on the inner side of the winding metal ring (26). The outer side of the winding metal ring (26) is sleeved on the inner side of the inner groove (11). The fluorine liner tube (2) is fixedly embedded with a spiral iron wire (27). Multiple horizontal iron wires (28) are horizontally fixed on the spiral iron wire (27). An inner ring groove (14) is opened on the inner side of one end of the pipe shell (1), and an outer shell extension pipe (17) is fixed to the other end of the pipe shell (1). The outer shell extension pipe (17) and the pipe shell (1) are an integral structure. The inner diameter of the outer shell extension pipe (17) is the same as the inner diameter of the pipe shell (1), and the outer diameter of the outer shell extension pipe (17) is the same as the inner diameter of the inner ring groove (14). Four slides (15) are evenly and horizontally opened on the inner side of the inner ring groove (14). One end of the slide (15) is an open structure and the other end is a closed structure. A short arc groove (16) is opened at the closed end of the inner ring groove (14). The short arc groove (16) is connected to the slide (15). Four arc blocks (18) are evenly fixed to the periphery of the outer shell extension pipe (17) away from the pipe shell (1). The length of the arc block (18) is the same as the width of the slide (15), and the width is the same as the width of the short arc groove (16). The first flange (12) is fixedly sleeved on the side of the pipe shell (1) near the inner ring groove (14). The first flange (12) is fixedly connected to the side away from the pipe shell (1) with a first fluoroplastic ring (19). The first fluoroplastic ring (19) is fixedly connected to the side away from the first flange (12) with a convex ring (110). The convex ring (110) and the first fluoroplastic ring (19) are an integral structure. Multiple first through holes (111) are uniformly and horizontally opened on the first fluoroplastic ring (19) and the first flange (12). The pipe shell (1) is fixedly sleeved with a second flange (13) on the periphery of the end away from the first flange (12). The second flange (13) is fixedly connected with a second fluoroplastic ring (112) on the side away from the pipe shell (1). A concave annular groove (113) is opened on the side of the second fluoroplastic ring (112) away from the second flange (13). The shape and size of the concave annular groove (113) are the same as the convex ring (110). Multiple second through holes (114) are opened horizontally on the second fluoroplastic ring (112) and the second flange (13). Multiple filling holes (115) are opened at the end of the pipe shell (1) directly above the four slides (15). The filling holes (115) are connected to the slides (15). The end of the filling hole (115) is fitted with an interference fit plug (116).

2. The high-strength spiral-wound fluoropolymer-lined pipe according to claim 1, characterized in that: The outer ring groove (21) is opened at the same vertical position as the inner ring groove (14) on the outer side of one end of the fluorine liner tube (2). The first inner liner extension tube (22) is fixed to the end of the fluorine liner tube (2) near the outer ring groove (21). The first inner liner extension tube (22) and the fluorine liner tube (2) are an integral structure. The thickness of the end of the first inner liner extension tube (22) away from the fluorine liner tube (2) is lower than the thickness of the other end.

3. A high-strength spiral-wound fluoropolymer-lined pipe according to claim 2, characterized in that: An arc-shaped groove (23) is opened on the inner side of the end of the fluoroliner tube (2) away from the first liner extension tube (22). The end of the fluoroliner tube (2) away from the first liner extension tube (22) is fixed to the second liner extension tube (24). The second liner extension tube (24) and the fluoroliner tube (2) are an integral structure.

4. A high-strength spiral-wound fluoropolymer-lined pipe according to claim 3, characterized in that: The arc-shaped annular groove (23) has the same shape and size as the first inner lining extension tube (22), the outer diameter of the second inner lining extension tube (24) has the same outer diameter as the fluorine inner lining tube (2), and the inner diameter of the second inner lining extension tube (24) has the same outer diameter as the outer annular groove (21).

5. A high-strength spiral-wound fluoropolymer-lined pipe according to claim 1, characterized in that: The preparation steps of the fluorine-lined tube (2) are as follows: Step 1: Ingredient preparation: 110-140 parts of polytetrafluoroethylene propylene, 21-34 parts of carbon black, 18-24 parts of quartz sand, 15-18 parts of thermoplastic polyurethane, 12-20 parts of bentonite, 5-8 parts of short glass fiber, 4-7 parts of coupling agent, 2-5 parts of lubricant, and 1-3 parts of plasticizer. Step 2: Mixing: Place polytetrafluoroethylene propylene, carbon black, thermoplastic polyurethane and lubricant into a mixer in sequence, heat to 280-300℃ and mix for 13-17 minutes to obtain the mixed mixture. Step 3: Quartz Sand Treatment: The quartz sand is soaked in hydrochloric acid and hydrofluoric acid in sequence. After soaking, it is washed with water, dried, and then placed in a vacuum environment for chlorination treatment. The temperature is maintained at 65-75℃. Under the action of chlorine gas, the alkali metal and alkaline earth metal impurities in the quartz sand are converted into gaseous chlorides. The chlorination treatment removes the alkali metal and alkaline earth metal impurities in the quartz sand and the impurities on the surface of the quartz sand particles, resulting in high-purity quartz sand. Step 4: Internal mixing: Add the mixture obtained in Step 2 and the high-purity quartz sand obtained in Step 3 into an internal mixer, then add bentonite, short glass fiber, coupling agent and plasticizer in sequence, and mix at a temperature of 290-310℃ for 30-40 minutes to obtain the internally mixed mixture. Step 5 Molding: The mixture obtained in Step 4 is added to a twin-screw extruder and extruded at a temperature of 275-290℃. It is then stamped and shaped by a die, cooled and solidified to obtain a fluorine-lined tube (2).

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