A method of bonding a tetrafluoroethylene liner

Abstract

This invention discloses a method for bonding PTFE liners, comprising the following specific steps: S1: Inner wall treatment: performing microporous treatment on the inner wall of the PTFE liner; S2: Implanting silane coupling agent: implanting silane coupling agent into the micropores using vapor deposition; S3: Coating: coating the inner wall of the PTFE liner with high-temperature resistant epoxy resin for later use; S4: Bonding: attaching the coated PTFE liner to the inner wall of the tube to complete the bonding; S5: Smoothing: smoothing the inner wall of the PTFE liner using a smoothing device; S1, the inner wall treatment includes the following specific steps: S11: ultrasonically cleaning the PTFE surface with acetone and isopropanol to remove grease and particulate contaminants; S12: low-temperature plasma pre-activation; S13: etching honeycomb-shaped micropores on the PTFE surface using low-temperature plasma. The PTFE liner bonding method disclosed in this invention can greatly improve peel strength and better adapt to high stress or high vibration environments.

Description

Technical Field

[0001] This invention relates to the field of PTFE liner bonding technology, and more particularly to a PTFE liner bonding method. Background Technology

[0002] PTFE lining is a lining material made of polytetrafluoroethylene (PTFE) as the base material. It is applied to the inner surface of metal or non-metal substrates in pipes, valves, storage tanks, and other equipment through a lining process, forming a corrosion-resistant and wear-resistant protective layer. Its core characteristics stem from PTFE's chemical inertness, temperature resistance, and low coefficient of friction, making it an ideal choice for corrosion resistance in industrial applications. PTFE can resist the erosion of strong acids (such as sulfuric acid and nitric acid), strong alkalis (such as sodium hydroxide), and organic solvents, protecting the substrate from chemical corrosion.

[0003] However, PTFE has a low surface energy (approximately 18 mJ / m²), making it difficult to bond directly to the substrate. Even after traditional treatment, the PTFE liner still suffers from insufficient interfacial strength. Summary of the Invention

[0004] This invention discloses a bonding method for PTFE liners, which aims to solve the technical problem that PTFE liners still have insufficient interfacial strength after being treated by traditional methods.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A method for bonding a PTFE liner includes the following specific steps: S1: Inner wall treatment: microporous treatment is performed on the inner wall of the PTFE liner; S2: Silane coupling agent implantation: silane coupling agent is implanted into the micropores by vapor deposition; S3: Adhesive coating: high-temperature resistant epoxy resin is coated on the inner wall of the PTFE liner for later use; S4: Bonding: the PTFE liner after adhesive coating is adhered to the inner wall of the tube to complete the bonding; S5: Smoothing: the inner wall of the PTFE liner is smoothed using a smoothing device.

[0007] The inner wall treatment in S1 includes the following specific steps: S11: Ultrasonic cleaning of the PTFE surface with acetone and isopropanol to remove grease and particulate contaminants; S12: Low-temperature plasma pre-activation; S13: Etching honeycomb micropores on the PTFE surface using low-temperature plasma.

[0008] By performing microporous treatment before coating, which is an innovation in microstructure, the specific surface area of ​​the PTFE liner can be significantly increased. Subsequently, by implanting silane coupling agents into the micropores and coating with epoxy resin, the interfacial bonding strength can be greatly enhanced, enabling it to better adapt to high stress or high vibration environments.

[0009] In a preferred embodiment, the smoothing device includes: a linear electric guide rail, with a carriage movably connected to the linear electric guide rail; a smoothing mechanism connected to one side of the carriage; and a heating mechanism fixedly connected to the smoothing mechanism.

[0010] The smoothing mechanism includes: a side support plate, which is fixedly connected to the top outer wall of the slide; and an inner sleeve, which is movably connected to one side of the side support plate, and a motor is fixedly connected to one end of the inner sleeve, with the motor installed on one side outer wall of the side support plate.

[0011] The smoothing mechanism further includes: a support frame, fixedly connected to one side of the outer wall of the inner frame; multiple upright plates, equidistantly movably connected to the outer periphery of the support frame, and each upright plate has a groove on both sides; multiple extended abutments, two in a group, movably fitting against the outer walls of both sides of the upright plates, and each group of two extended abutments has a crossbar fixedly connected to both ends, the crossbar being located in the groove.

[0012] The smoothing mechanism further includes: a pneumatic rod, fixedly connected to one outer wall of the upright plate, and its output end fixedly connected to the inner wall of one of the extended abutments; a mounting plate, fixedly connected to the other outer wall of the upright plate, and a plurality of springs fixedly connected to the top of the mounting plate, the other ends of the springs being fixedly connected to the inner wall of the extended abutments.

[0013] The smoothing mechanism further includes: a connecting sleeve, which is fixedly connected to one side outer wall of the side support plate, and an inner sleeve is movably fitted inside the connecting sleeve; a linkage rod, which is rotatably connected to the inner walls of both sides of the support frame, and one end of the linkage rod is fixedly connected to a second motor, which is fixedly installed on one side outer wall of the support frame, with the motor located inside the inner sleeve.

[0014] The smoothing mechanism further includes: two circular side plates, fixedly connected to the linkage rod, and each circular side plate is provided with multiple arc-shaped through slots; multiple sliding rods, fixedly connected to the bottom ends of multiple upright plates, and the two ends of each sliding rod are respectively movably connected to the arc-shaped through slots on the two circular side plates; and multiple limiting frames, fixedly connected to the inner wall of one side of the support frame, and each limiting frame is movably attached to the outer side of the multiple upright plates.

[0015] With a smoothing mechanism, after the PTFE lining is bonded, the tube is placed on an external support platform. Then, a linear electric guide rail drives the slide to move, allowing the smoothing mechanism to extend into the inner wall of the tube. A motor drives the support frame to rotate as a whole, thereby causing multiple upright plates and extended blocks to rotate back and forth. This rotation performs one round of smoothing, followed by the retracting air rod rotating again. This smoothing method can first defoam a large area, and then specifically strengthen weak areas, thereby improving the bonding strength of the interface and greatly improving the uniformity of the bonding.

[0016] In a preferred embodiment, the heating mechanism includes: a controller, fixedly connected to one side of the outer wall of the support frame; and multiple U-shaped heating plates, fixedly embedded in the top inner wall of each upright plate, and electrically connected to the controller.

[0017] The heating mechanism further includes: a heat-conducting pad, which is fixedly attached to the top outer wall of the U-shaped heating plate, and the heat-conducting pad is made of heat-conducting silicone; and two copper sheets, which are fixedly embedded in the top inner wall of the two extended blocks and are movably attached to the outer wall of the U-shaped heating plate.

[0018] Equipped with a heating mechanism, the controller controls multiple U-shaped heating plates to heat the surface. Heat conduction is achieved through the use of heat-conducting pads and copper sheets on both sides, ensuring heating of the pressing surface regardless of the size of the pressing area, making it highly adaptable.

[0019] As described above, a method for bonding a PTFE liner includes the following specific steps: S1: Inner wall treatment: microporous treatment is performed on the inner wall of the PTFE liner; S2: Silane coupling agent implantation: silane coupling agent is implanted into the micropores using vapor deposition; S3: Adhesive coating: high-temperature resistant epoxy resin is coated onto the inner wall of the PTFE liner for later use; S4: Bonding: the adhesive-coated PTFE liner is adhered to the inner wall of the tube to complete the bonding; S5: Smoothing: the inner wall of the PTFE liner is smoothed using a smoothing device. The PTFE liner bonding method provided by this invention has the technical effect of greatly improving peel strength and better adapting to high stress or high vibration environments. Attached Figure Description

[0020] Figure 1 This is a flowchart illustrating a specific method for bonding a PTFE liner proposed in this invention.

[0021] Figure 2 This is a schematic diagram of the overall structure of the smoothing device for a PTFE liner bonding method proposed in this invention.

[0022] Figure 3 This is a schematic diagram showing the disassembled smoothing mechanism of a PTFE liner bonding method proposed in this invention.

[0023] Figure 4 This is a partial disassembled schematic diagram of the smoothing mechanism in a PTFE liner bonding method proposed in this invention.

[0024] Figure 5 This is a cross-sectional view of the heating mechanism of a PTFE liner bonding method proposed in this invention.

[0025] In the diagram: 1. Linear electric guide rail; 2. Carriage; 3. Smoothing mechanism; 4. Heating mechanism; 301. Side support plate; 302. Connecting sleeve; 303. Motor 1; 304. Inner sleeve; 305. Slide rod; 306. Vertical plate; 307. Arc-shaped through slot; 308. Circular side plate; 309. Linkage rod; 310. Support frame; 311. Limiting frame; 312. Motor 2; 313. Extension stop block; 314. Cross frame; 315. Spring; 316. Mounting plate; 317. Groove; 318. Gas spring; 401. Controller; 402. Copper sheet; 403. Thermal pad; 404. U-shaped heating plate. Detailed Implementation

[0026] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0027] The PTFE liner bonding method disclosed in this invention is mainly applied to PTFE liner bonding scenarios.

[0028] Reference Figure 1 A method for bonding a PTFE liner includes the following specific steps: S1: Inner wall treatment: performing microporous treatment on the inner wall of the PTFE liner; S2: Implanting a silane coupling agent: implanting a silane coupling agent into the micropores using vapor deposition; S3: Coating: coating the inner wall of the PTFE liner with high-temperature resistant epoxy resin for later use; S4: Bonding: attaching the coated PTFE liner to the inner wall of the tube to complete the bonding; S5: Smoothing: smoothing the inner wall of the PTFE liner using a smoothing device; By performing microporous treatment before coating, which is an innovation in microstructure, the specific surface area of ​​the PTFE liner can be significantly increased, and the peel strength between the PTFE liner and the substrate can be significantly improved. Subsequently, the silane coupling agent is implanted into the micropores by vapor deposition, which can greatly enhance the interfacial bonding strength. The vapor deposition method can also greatly improve the uniformity of chemical bonding. The subsequent coating with epoxy resin can further improve the peel strength, making it better adaptable to high stress or high vibration environments.

[0029] Reference Figure 1 In a preferred embodiment, S1, the inner wall treatment includes the following specific steps: S11: ultrasonically cleaning the PTFE surface with acetone and isopropanol to remove grease and particulate contaminants; S12: pre-activation with low-temperature plasma; S13: etching honeycomb micropores on the PTFE surface using low-temperature plasma.

[0030] Reference Figures 2-4 In a preferred embodiment, the smoothing device includes: a linear electric guide rail 1, a carriage 2 movably connected to the linear electric guide rail 1; a smoothing mechanism 3 connected to one side of the carriage 2; and a heating mechanism 4 fixedly connected to the smoothing mechanism 3.

[0031] The smoothing mechanism 3 includes: a side support plate 301, which is fixedly connected to the top outer wall of the slide 2; and an inner sleeve 304, which is movably connected to one side of the side support plate 301, and a motor 303 is fixedly connected to one end of the inner sleeve 304. The motor 303 is installed on one side outer wall of the side support plate 301.

[0032] Reference Figure 3 and Figure 4 In a preferred embodiment, the smoothing mechanism 3 further includes: a support frame 310, fixedly connected to one side of the outer wall of the inner sleeve frame 304; a plurality of upright plates 306, equidistantly movably connected to the outer periphery of the support frame 310, and each upright plate 306 has a groove 317 on both sides; a plurality of extended abutments 313, two in a group, respectively movably attached to the outer walls of both sides of the upright plate 306, and each of the two extended abutments 313 in a group has a crossbar 314 fixedly connected to both ends, the crossbar 314 being located in the groove 317.

[0033] Reference Figure 3 and Figure 4 In a preferred embodiment, the smoothing mechanism 3 further includes: a pneumatic rod 318, fixedly connected to one side of the outer wall of the upright plate 306, with its output end fixedly connected to the inner wall of one of the extended abutments 313; and a mounting plate 316, fixedly connected to the other side of the upright plate 306, with a plurality of springs 315 fixedly connected to the top of the mounting plate 316, the other ends of the springs 315 being fixedly connected to the inner wall of the extended abutments 313. After the PTFE liner is bonded, the tube is placed on the external support platform, and then the linear electric guide rail 1 drives the slide 2 to move, causing the smoothing mechanism 3 to extend into the tube. The inner wall of the PTFE liner is smoothed by the rotation of the support frame 310 driven by the motor 303. This rotation causes multiple upright plates 306 and extended abutments 313 to rotate back and forth. The top contact surfaces of the upright plates 306 and extended abutments 313 contact the inner wall of the PTFE liner, and the rotation smooths the surface. Then the air rod 318 is retracted, so that the extended abutments 313 are lower than the upright plates 306. The surface of the upright plates 306 then contacts the inner wall of the PTFE liner to smooth the surface. This smoothing method first defoams a large area and then strengthens weak areas in a targeted manner, thereby improving the bonding strength of the interface and greatly improving the uniformity of the bond.

[0034] Reference Figure 3 and Figure 4 In a preferred embodiment, the smoothing mechanism 3 further includes: a connecting sleeve 302, which is fixedly connected to one side of the outer wall of the side support plate 301, and an inner sleeve 304 is movably sleeved within the connecting sleeve 302; a linkage rod 309, which is rotatably connected to the inner walls of both sides of the support frame 310, and one end of the linkage rod 309 is fixedly connected to a second motor 312, and the second motor 312 is fixedly installed on one side of the outer wall of the support frame 310, with the motor 312 located within the inner sleeve 304.

[0035] Reference Figure 3 and Figure 4 In a preferred embodiment, the smoothing mechanism 3 further includes: two circular side plates 308, fixedly connected to the linkage rod 309, and each circular side plate 308 having a plurality of arc-shaped through slots 307 arranged around it; a plurality of sliding rods 305, fixedly connected to the bottom ends of a plurality of upright plates 306, and each sliding rod 305 having its two ends movably connected to the arc-shaped through slots 307 on the two circular side plates 308; and a plurality of limiting frames 311, simultaneously fixedly connected to one inner wall of the support frame 310, and Each limiting bracket 311 is movably attached to the outer side of multiple upright plates 306. By rotating the motor 312, the linkage rod 309 can be rotated, which can change the contact position between each arc-shaped through groove 307 and the slide rod 305. The multiple limiting brackets 311 provide a limiting effect on the longitudinal movement of the upright plates 306, allowing the multiple upright plates 306 to move a short distance outward or inward, which facilitates the smoothing mechanism 3 to be smoothly inserted into the tube. The spring 315 provides a squeezing force to ensure the tight squeezing of the extended blocks 313 on both sides.

[0036] Reference Figure 5 In a preferred embodiment, the heating mechanism 4 includes: a controller 401, which is fixedly connected to one side of the outer wall of the support frame 310; and a plurality of U-shaped electric heating plates 404, which are fixedly embedded in the top inner wall of each upright plate 306 and are electrically connected to the controller 401.

[0037] Reference Figure 5 In a preferred embodiment, the heating mechanism 4 further includes: a heat-conducting pad 403, fixedly attached to the top outer wall of the U-shaped heating plate 404, and the heat-conducting pad 403 is made of thermally conductive silicone; two copper sheets 402, fixedly embedded in the top inner wall of the two extended blocks 313, and movably attached to the outer wall of the U-shaped heating plate 404. The controller 401 controls the heating of multiple U-shaped heating plates 404, and conducts heat through the heat-conducting pad 403. The heat-conducting pad 403 contacts the inner wall of the PTFE liner, and heats up while pressing, optimizing the pressing effect. In addition, heat is lost during the heat conduction process of thermally conductive silicone, avoiding excessively high contact surface temperature. The copper sheets 402 on both sides can conduct heat, and heating of the pressing surface can be achieved regardless of the size of the pressing area, with high adaptability.

[0038] Working principle: The micropore treatment is an innovative microscopic morphology technique that significantly increases the specific surface area of ​​the PTFE liner and improves the peel strength between the PTFE liner and the substrate. Subsequently, silane coupling agents are implanted into the micropores via vapor deposition, which greatly enhances the interfacial bonding strength. Vapor deposition also significantly improves the uniformity of chemical bonding. Subsequent epoxy resin coating further enhances the peel strength, allowing for better adaptation to high-stress or high-vibration environments. After the PTFE liner is bonded, the tube is placed on an external support platform, and then the linear electric guide rail 1 drives the slide 2 to move, facilitating the smoothing mechanism 3. The air rod 318 extends into the inner wall of the tube and drives the support frame 310 to rotate as a whole via motor 303. This causes multiple vertical plates 306 and extended abutments 313 to rotate reciprocally. The top contact surfaces of the vertical plates 306 and extended abutments 313 contact the inner wall of the PTFE liner, and the rotation performs a smoothing process. Then, the air rod 318 retracts, making the extended abutments 313 lower than the vertical plates 306. The smoothing is performed only by the contact surfaces of the vertical plates 306 against the inner wall of the PTFE liner. This smoothing method achieves large-area defoaming first, followed by targeted reinforcement of weak areas, thus improving the bonding strength of the interface and greatly enhancing the uniformity of the bond.

[0039] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for bonding a PTFE liner, characterized in that, The specific steps include the following: S1: Inner wall treatment: Microporous treatment is performed on the inner wall of the PTFE liner; S2: Implantation of silane coupling agent: Silane coupling agent is implanted into micropores by vapor deposition; S3: Coating: Apply high-temperature resistant epoxy resin to the inner wall of the PTFE liner for later use; S4: Bonding: The PTFE liner after applying adhesive is attached to the inner wall of the tube to complete the bonding; S5: Smoothing: Smoothing the inner wall of the PTFE liner using a smoothing device.

2. The bonding method for a PTFE liner according to claim 1, characterized in that, The inner wall treatment in step S1 includes the following specific steps: S11: Use acetone and isopropanol for ultrasonic cleaning of PTFE surfaces to remove grease and particulate contaminants; S12: Low-temperature plasma pre-activation; S13: Low-temperature plasma is used to etch honeycomb micropores on the PTFE surface.

3. The bonding method for a PTFE liner according to claim 1, characterized in that, The smoothing device includes: A linear electric guide rail (1) and a carriage (2) are movably connected to the linear electric guide rail (1); The smoothing mechanism (3) is connected to one side of the carriage (2); The heating mechanism (4) is fixedly connected to the smoothing mechanism (3); The smoothing mechanism (3) includes: Side support plate (301) is fixedly connected to the top outer wall of the carriage (2); The inner frame (304) is movably connected to one side of the side support plate (301), and one end of the inner frame (304) is fixedly connected to a motor (303), which is installed on the outer wall of one side of the side support plate (301).

4. The method for bonding a PTFE liner according to claim 3, characterized in that, The smoothing mechanism (3) also includes: The support frame (310) is fixedly connected to one side of the outer wall of the inner sleeve frame (304); Multiple upright plates (306) are equidistantly and movably connected to the outer periphery of the support frame (310), and each upright plate (306) has a groove (317) on both sides. Multiple extension blocks (313) are arranged in groups of two and are respectively attached to the outer walls of the two sides of the upright plate (306). At the same time, the two ends of each group of two extension blocks (313) are fixedly connected to a crossbeam (314), which is located in the groove (317).

5. The bonding method for a PTFE liner according to claim 4, characterized in that, The smoothing mechanism (3) also includes: The gas spring (318) is fixedly connected to the outer wall of one side of the upright plate (306), and its output end is fixedly connected to the inner wall of one of the extension blocks (313); Mounting plate (316) is fixedly connected to the outer wall of the other side of the upright plate (306), and a plurality of springs (315) are fixedly connected to the top of the mounting plate (316), and the other end of the springs (315) is fixedly connected to the inner wall of the extension block (313).

6. The method for bonding a PTFE liner according to claim 5, characterized in that, The smoothing mechanism (3) also includes: The connecting sleeve (302) is fixedly connected to the outer wall of one side of the side support plate (301), and the inner sleeve (304) is movably sleeved inside the connecting sleeve (302); The linkage rod (309) is rotatably connected to the inner walls of both sides of the support frame (310). One end of the linkage rod (309) is fixedly connected to the second motor (312), and the second motor (312) is fixedly installed on the outer wall of one side of the support frame (310). The motor (312) is located inside the inner sleeve frame (304).

7. The bonding method for a PTFE liner according to claim 6, characterized in that, The smoothing mechanism (3) also includes: Two circular side plates (308) are fixedly connected to the linkage rod (309), and each circular side plate (308) is provided with multiple arc-shaped through slots (307) around it. Multiple sliding rods (305) are fixedly connected to the bottom ends of multiple upright plates (306), and the two ends of each sliding rod (305) are respectively movably connected to the arc-shaped through grooves (307) on two circular side plates (308); Multiple limit frames (311) are fixedly connected to one side of the inner wall of the support frame (310), and each limit frame (311) is movably attached to the outer side of multiple upright plates (306).

8. The bonding method for a PTFE liner according to claim 4, characterized in that, The heating mechanism (4) includes: The controller (401) is fixedly connected to one side of the outer wall of the support frame (310); Multiple U-shaped heating plates (404) are fixedly embedded in the top inner wall of each upright plate (306) and are electrically connected to the controller (401).

9. The method for bonding a PTFE liner according to claim 8, characterized in that, The heating mechanism (4) further includes: A thermal pad (403) is fixedly attached to the top outer wall of the U-shaped heating plate (404), and the thermal pad (403) is made of thermally conductive silicone. Two copper sheets (402) are fixedly embedded in the inner wall of the top of two extended blocks (313) and movably attached to the outer wall of the U-shaped heating plate (404).

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