FEP tube forming apparatus and forming method

Abstract

This application discloses an FEP pipe forming device and method. The FEP pipe forming device includes a clamping assembly, a heating ring, and an extrusion assembly. The clamping assembly is used to clamp and fix the FEP pipe, the heating ring is used to generate heat to melt the end of the FEP pipe, and the extrusion assembly is used to apply external force to the molten FEP pipe for shaping. This application uses the clamping assembly to clamp the FEP pipe and uses a first forming mold and a second forming mold to pre-shape the end of the FEP pipe. This allows the concave structure at the end of the FEP pipe to better fill the gap in the joint when it is subsequently connected to a connector, thereby achieving higher connection strength and better sealing performance. This application relates to the field of thermoforming technology.

Description

Technical Field

[0001] This application relates to an FEP pipe forming equipment and forming method in the field of hot melt forming technology. Background Technology

[0002] FEP (fluorinated ethylene propylene) is a type of chemical substance, a copolymer of tetrafluoroethylene and hexafluoropropylene. FEP materials have lower tensile strength, abrasion resistance, and creep resistance than many engineering plastics, and are chemically inert with a low dielectric constant over a wide temperature and frequency range, making them widely used in industrial production. FEP hoses are tubular parts formed by high-temperature melting and extrusion of FEP granules.

[0003] In the current technology, the ends of FEP pipes need to be connected to connectors. Since the connection strength with external equipment must be considered, the connectors are generally metal connectors. FEP pipes and metal connectors are generally connected by thermoforming extrusion. At high temperature, the end of the FEP pipe melts and adheres to the surface of the metal connector. Then, external force is used to press the FEP pipe and the metal connector tightly together.

[0004] However, in practical applications, it has been found that in existing connection methods, due to the irregularity of the outer contour of the joint, it is difficult for the FEP pipe to adhere as closely as possible to the joint surface after heat fusion. When there are small gaps on the outer wall of the joint, the ductility of the FEP material is insufficient to fill these gaps, leading to a decrease in the sealing performance between the FEP pipe and the joint, and the possibility of leakage. Moreover, because the connection between the FEP pipe and the joint is not strong enough, it is also prone to loosening under external force.

[0005] Application content

[0006] The purpose of this application is to at least solve one of the technical problems existing in the prior art, and to provide an FEP pipe forming equipment and forming method that can improve the connection strength and sealing performance of FEP pipe and joint.

[0007] According to a first aspect of this application, an FEP tube forming apparatus and a forming method are provided, comprising:

[0008] A clamping assembly includes a first clamping seat, a second clamping seat, and a clamping drive motor, wherein the drive motor drives the second clamping seat to move closer to or away from the first clamping seat;

[0009] The first clamping seat and the second clamping seat are both provided with clamping grooves to accommodate the FEP tube. The outer side of the first clamping seat and the second clamping seat is provided with a semi-cylindrical boss. When the first clamping seat and the second clamping seat are spliced ​​together, the clamping grooves in the first clamping seat and the second clamping seat squeeze the FEP tube located therein to fix it. The bosses on the first clamping seat and the second clamping seat are spliced ​​together to form a cylindrical structure. The top of the cylindrical structure is reserved with a through hole for the FEP tube to extend out.

[0010] A heating ring, which can be fitted onto the outside of a cylindrical structure formed by splicing protrusions on the first clamping seat and the second clamping seat;

[0011] An extrusion assembly includes a vertical sliding mechanism, an extrusion table, a first forming die, and a second forming die. The extrusion table is movably connected to the sliding platform of the vertical sliding mechanism. Both the first forming die and the second forming die are mounted on the extrusion table. The end of the first forming die is provided with a first annular groove, and the end of the second forming die is provided with a second annular groove. The difference is that the bottom of the first annular groove is a flat surface, while the bottom of the second annular groove is provided with a raised annular pressure strip.

[0012] According to a first aspect of the present application, the clamping assembly further includes a support frame, the first clamping seat is fixedly connected to the support frame, and the second clamping seat is slidably connected to the support frame.

[0013] According to a first aspect embodiment of this application, the first clamping seat is provided with a limiting groove, and the second clamping seat is provided with a limiting protrusion. When the first clamping seat and the second clamping seat are assembled together, the limiting protrusion can be inserted into the limiting groove to achieve limiting.

[0014] According to a first aspect of the present application, the edge of the limiting protrusion is provided with a rounded chamfer.

[0015] According to a first aspect of the present application, the extrusion table is rotatably connected to the sliding platform of the vertical sliding mechanism, and the first forming mold and the second forming mold are arranged in a circular array around the rotation axis of the extrusion table.

[0016] According to a first aspect of the present application, the extrusion table is slidably connected to the sliding platform of the vertical sliding mechanism and the sliding direction is horizontal. The first forming mold and the second forming mold are mounted side by side on the extrusion table.

[0017] According to a first aspect embodiment of this application, both the first molding die and the second molding die are provided with a positioning post at their center, and the positioning post can extend into the FEP tube.

[0018] According to a first aspect of the present application, the end of the positioning post is further shaped as a frustum or a cone.

[0019] According to a first aspect embodiment of this application, both the first molding die and the second molding die are provided with retaining rings on their sides, and the retaining rings can close the upper opening of the heating ring to reduce heat loss.

[0020] According to a second aspect of this application, a forming method based on the above-described FEP tube forming equipment is provided, comprising the following steps:

[0021] The EFP tube to be formed is passed from bottom to top through the bottom of the clamping assembly, so that the EFP tube is located between the clamping groove of the first clamping seat and the clamping groove of the second clamping seat.

[0022] Start the clamping drive motor so that the first clamping seat and the second clamping seat together clamp the EFP tube, with the end of the EFP tube being 5-20mm higher than the cylindrical structure;

[0023] The heating ring is fitted over the outside of the cylindrical structure;

[0024] The heating ring is activated, and the heating temperature of the heating ring is set between 280 and 350°C, with a heating time between 30 and 60 seconds.

[0025] The vertical sliding mechanism drives the extrusion table to move downward, causing the first forming mold to apply pressure to the end of the FEP tube, and the end of the FEP tube is pressed outward in the first annular groove;

[0026] The vertical sliding mechanism drives the extrusion table to move upward, and the extrusion table switches to the second forming mold;

[0027] The vertical sliding mechanism drives the extrusion table to move downward, and drives the second forming mold to apply pressure to the end of the FEP tube. The end of the FEP tube is pressed by the annular pressure strip in the second annular groove, creating a concave structure, which is shaped for 40-60 seconds.

[0028] The vertical sliding mechanism drives the extrusion platform to move upward and remove the heating ring. The clamping drive motor drives the second clamping seat away from the first clamping seat and removes the FEP tube from it.

[0029] The beneficial effects of the embodiments of this application include at least the following: This application clamps the FEP tube with a clamping assembly and pre-forms the end of the FEP tube with a first forming mold and a second forming mold, so that when the FEP tube is subsequently connected to the connector, the concave structure at its end can better fill the gap of the connector, thereby achieving higher connection strength and obtaining better sealing performance. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly explained below. Obviously, the described drawings are only a part of the embodiments of this application, and not all of them. Those skilled in the art can obtain other design schemes and drawings based on these drawings without creative effort.

[0031] Figure 1 This is a three-dimensional view of the FEP tube forming apparatus according to the first aspect of this application;

[0032] Figure 2 This is a three-dimensional view of the clamping assembly 100 in the FEP tube forming equipment according to the first aspect of this application;

[0033] Figure 3 This is a cross-sectional view of the first clamping seat 110 and the second clamping seat 120 in the FEP tube forming equipment according to the first aspect embodiment of this application;

[0034] Figure 4 This is a schematic diagram of the operation of the extrusion assembly 300 in the FEP tube forming equipment according to the first aspect of this application;

[0035] Figure 5 This is a cross-sectional view of the first forming mold 330 and the second forming mold 340 in the FEP tube forming equipment of the first aspect embodiment of this application.

[0036] Reference numerals: 100-Clamping assembly, 110-First clamping seat, 111-Limiting groove, 120-Second clamping seat, 121-Limiting protrusion, 130-Clamping groove, 140-Protrusion, 150-Clamping drive motor, 160-Support frame, 200-Heating ring, 300-Extrusion assembly, 310-Vertical sliding mechanism, 320-Extrusion table, 330-First forming mold, 331-First annular groove, 340-Second forming mold, 341-Second annular groove, 3411-Annular pressure strip, 350-Positioning post, 360-Retaining ring, 400-Controller. Detailed Implementation

[0037] This section will describe in detail the specific embodiments of this application. Preferred embodiments of this application are shown in the accompanying drawings. The purpose of the drawings is to supplement the textual description with graphics, so that people can intuitively and vividly understand each technical feature and the overall technical solution of this application, but they should not be construed as limiting the scope of protection of this application.

[0038] In the description of this application, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0039] In the description of this application, "several" means one or more, "more than" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0040] In the description of this application, unless otherwise expressly defined, terms such as "setup," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this application in conjunction with the specific content of the technical solution.

[0041] In the current technology, the ends of FEP pipes need to be connected to connectors. Since the connection strength with external equipment must be considered, the connectors are generally metal connectors. FEP pipes and metal connectors are generally connected by thermoforming extrusion. At high temperature, the end of the FEP pipe melts and adheres to the surface of the metal connector. Then, external force is used to press the FEP pipe and the metal connector tightly together.

[0042] However, in practical applications, it has been found that in existing connection methods, due to the irregularity of the outer contour of the joint, it is difficult for the FEP pipe to adhere as closely as possible to the joint surface after heat fusion. When there are small gaps on the outer wall of the joint, the ductility of the FEP material is insufficient to fill these gaps, leading to a decrease in the sealing performance between the FEP pipe and the joint, and the possibility of leakage. Moreover, because the connection between the FEP pipe and the joint is not strong enough, it is also prone to loosening under external force.

[0043] In response, this application proposes an FEP pipe forming equipment and forming method, which clamps the FEP pipe with a clamping assembly 100 and pre-forms the end of the FEP pipe with a first forming mold 330 and a second forming mold 340, so that when the FEP pipe is subsequently connected to the joint, the concave structure at its end can better fill the gap of the joint, thereby achieving higher connection strength and obtaining better sealing performance.

[0044] Reference Figure 1 The FEP tube forming equipment in the first aspect embodiment of this application includes a clamping assembly 100, a heating ring 200, and an extrusion assembly 300, wherein the clamping assembly 100 is used to clamp and fix the FEP tube, the heating ring 200 is used to generate heat to melt the end of the FEP tube, and the extrusion assembly 300 is used to apply external force to the molten FEP tube for shaping.

[0045] Specifically, refer to Figure 2 The clamping assembly 100 includes a first clamping seat 110, a second clamping seat 120, a clamping drive motor 150, and a support frame 160. The first clamping seat 110 is fixedly connected to the support frame 160, and the support frame 160 has a sliding groove that allows the second clamping seat 120 to slide, thus forming a sliding connection between the two. Driven by the drive motor 150, the second clamping seat 120 can move closer to or further away from the first clamping seat 110. When the first clamping seat 110 and the second clamping seat 120 come into contact, they can be joined together.

[0046] Among them, reference Figure 3 Both the first clamping seat 110 and the second clamping seat 120 have clamping grooves 130 to accommodate the FEP tube, and both the first clamping seat 110 and the second clamping seat 120 have semi-cylindrical bosses 140 on their outer sides. When the first clamping seat 110 and the second clamping seat 120 are spliced ​​together, the clamping grooves 130 in the first clamping seat 110 and the second clamping seat 120 compress the FEP tube located therein to fix it; the bosses 140 on the first clamping seat 110 and the second clamping seat 120 are spliced ​​together to form a cylindrical structure, and the top of the cylindrical structure has a through hole for the FEP tube to extend out.

[0047] Furthermore, the first clamping seat 110 is provided with a limiting groove 111, and the second clamping seat 120 is provided with a limiting protrusion 121. When the first clamping seat 110 and the second clamping seat 120 are assembled together, the limiting protrusion 121 can be inserted into the limiting groove 111 to achieve limiting, reducing the possibility that the second clamping seat 120 may fail to be successfully assembled with the first clamping seat 110 due to positional displacement during movement. The edge of the limiting protrusion 121 is provided with a rounded chamfer to make the limiting protrusion 121 easier to insert.

[0048] After the first clamping seat 110 and the second clamping seat 120 are assembled together, the heating ring 200 can be fitted onto the outside of the cylindrical structure formed by the protrusions 140 on the first clamping seat 110 and the second clamping seat 120. On the one hand, it can play a limiting role during the heating process to prevent the first clamping seat 110 and the second clamping seat 120 from accidentally separating; on the other hand, it can transfer heat to the FEP tube through the first clamping seat 110 and the second clamping seat 120 to complete the melting of the FEP tube.

[0049] Reference Figure 4 The extrusion assembly 300 includes a vertical sliding mechanism 310, an extrusion table 320, a first forming die 330, and a second forming die 340. The extrusion table 320 is movably connected to the sliding platform of the vertical sliding mechanism 310, which drives the extrusion table 320 to move vertically. The first forming die 330 and the second forming die 340 are mounted on the extrusion table 320 for performing two shaping operations on the FEP tube, thereby ensuring that the extruded FEP tube conforms to a predetermined shape. It is easily understood that multiple forming dies can also be provided for multiple shaping operations, thereby enabling the extrusion of more complex shapes.

[0050] Regarding the movable connection between the extrusion table 320 and the vertical sliding mechanism 310, in some embodiments, the extrusion table 320 is rotatably connected to the sliding platform of the vertical sliding mechanism 310, and the extrusion table 320 is disc-shaped and can rotate around a rotation axis. The first molding die 330 and the second molding die 340 are arranged in a circumferential array around the rotation axis of the extrusion table 320. When it is necessary to switch between different molding dies, the different molding dies can be moved to the working position by rotating the extrusion table 320.

[0051] In this embodiment, the extrusion table 320 is slidably connected to the sliding platform of the vertical sliding mechanism 310, and the sliding direction is horizontal, so that the extrusion table 320 can move in the horizontal direction. The first molding die 330 and the second molding die 340 are mounted side by side on the extrusion table 320, and different molding dies can be switched to reach the working position by sliding the extrusion table 320.

[0052] For the specific structure of the first molding die 330 and the second molding die 340, refer to Figure 5The first forming mold 330 has a first annular groove 331 at its end, and the second forming mold 340 has a second annular groove 341 at its end. The difference is that the bottom of the first annular groove 331 is flat, so that when it contacts the end of the FEP tube, the end of the FEP tube is pressed outward within the first annular groove 331. The bottom of the second annular groove 341 has a raised annular pressure strip 3411, so that when it contacts the end of the FEP tube, the end of the FEP tube forms a concave structure under the pressure of the annular pressure strip 3411. This concave structure makes it easier to adapt to the shape of the connector during subsequent assembly.

[0053] Furthermore, both the first forming mold 330 and the second forming mold 340 are provided with a positioning post 350 in the center. The positioning post 350 can extend into the FEP tube and support the inner wall of the FEP tube during extrusion, so that the FEP tube can only turn outward and not inward when it is deformed by pressure. The end of the positioning post 350 is frustoconical or conical, making it easier for the positioning post to be inserted into the FEP tube.

[0054] Both the first forming mold 330 and the second forming mold 340 are provided with retaining rings 360 on their sides. When the first forming mold 330 or the second forming mold 340 is used for extrusion, the retaining rings 360 can enter the heating ring 200 to close the upper opening of the heating ring 200 and reduce heat loss.

[0055] This FEP molding equipment also includes a controller 400. The clamping assembly 100, heating ring 200 and extrusion assembly 300 are all electrically connected to the controller 400, and the controller 400 controls this FEP molding equipment.

[0056] The molding method in the second aspect embodiment of this application, performed using the aforementioned FEP molding equipment, includes the following steps:

[0057] S100. Pass the EFP tube to be formed from the bottom to the top through the clamping assembly 100, so that the EFP tube is located between the clamping groove 130 of the first clamping seat 110 and the clamping groove 130 of the second clamping seat 120.

[0058] S200. Start the clamping drive motor 150 so that the first clamping seat 110 and the second clamping seat 120 together clamp the EFP tube, with the end of the EFP tube being 5-20mm higher than the cylindrical structure.

[0059] S300. Fit the heating ring 200 onto the outside of the cylindrical structure;

[0060] S400. Start heating ring 200. The heating temperature of heating ring 200 is set between 280 and 350°C, and the heating time is between 30 and 60 seconds.

[0061] S500. The vertical sliding mechanism 310 drives the extrusion table 320 to move downward, causing the first forming mold 330 to apply pressure to the end of the FEP tube, and the end of the FEP tube is pressed outward in the first annular groove 331.

[0062] S600. The vertical sliding mechanism 310 drives the extrusion table 320 to move upward, and the extrusion table 320 switches to the second forming mold 340;

[0063] S700. The vertical sliding mechanism 310 drives the extrusion table 320 to move downward, and drives the second forming mold 340 to apply pressure to the end of the FEP tube. The end of the FEP tube is pressed by the annular pressure strip 3411 in the second annular groove 341, creating a concave structure, which is shaped for 40 to 60 seconds.

[0064] S800. The vertical sliding mechanism 310 drives the extrusion table 320 to move upward, remove the heating ring 200, and the clamping drive motor 150 drives the second clamping seat 120 away from the first clamping seat 110, so as to remove the FEP tube from it.

[0065] The above is a detailed description of the preferred embodiments of this application. However, this application is not limited to the embodiments described. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of this application. All such equivalent modifications or substitutions are included within the scope defined by the claims of this application.

Claims

1. An FEP pipe forming device, characterized in that, include: The clamping assembly (100) includes a first clamping seat (110), a second clamping seat (120), and a clamping drive motor (150), wherein the drive motor (150) drives the second clamping seat (120) to move closer to or away from the first clamping seat (110); The first clamping seat (110) and the second clamping seat (120) are both provided with clamping grooves (130) to accommodate the FEP tube. The outer sides of the first clamping seat (110) and the second clamping seat (120) are provided with semi-cylindrical bosses (140). When the first clamping seat (110) and the second clamping seat (120) are spliced ​​together, the clamping grooves (130) in the first clamping seat (110) and the second clamping seat (120) squeeze the FEP tube located therein to fix it. The bosses (140) on the first clamping seat (110) and the second clamping seat (120) are spliced ​​together to form a cylindrical structure. The top of the cylindrical structure is reserved with a through hole for the FEP tube to extend out. Heating ring (200) can fit on the outside of a cylindrical structure formed by splicing the bosses (140) on the first clamping seat (110) and the second clamping seat (120); The extrusion assembly (300) includes a vertical sliding mechanism (310), an extrusion table (320), a first forming die (330), and a second forming die (340). The extrusion table (320) is movably connected to the sliding platform of the vertical sliding mechanism (310). The first forming die (330) and the second forming die (340) are both mounted on the extrusion table (320). The end of the first forming die (330) is provided with a first annular groove (331), and the end of the second forming die (340) is provided with a second annular groove (341). The difference is that the bottom of the first annular groove (331) is a flat surface, and the bottom of the second annular groove (341) is provided with a raised annular pressure strip (3411).

2. The FEP tube forming equipment according to claim 1, characterized in that: The clamping assembly (100) includes a support frame (160), a first clamping seat (110) is fixedly connected to the support frame (160), and a second clamping seat (120) is slidably connected to the support frame (160).

3. The FEP tube forming equipment according to claim 1, characterized in that: The first clamping seat (110) is provided with a limiting groove (111), and the second clamping seat (120) is provided with a limiting protrusion (121). When the first clamping seat (110) and the second clamping seat (120) are assembled together, the limiting protrusion (121) can be inserted into the limiting groove (111) to achieve limiting.

4. The FEP tube forming equipment according to claim 3, characterized in that: The edge of the limiting protrusion (121) is provided with a rounded chamfer.

5. The FEP tube forming equipment according to claim 1, characterized in that: The extrusion table (320) is rotatably connected to the sliding platform of the vertical sliding mechanism (310), and the first forming mold (330) and the second forming mold (340) are arranged in a circular array around the rotation axis of the extrusion table (320).

6. The FEP tube forming equipment according to claim 1, characterized in that: The extrusion table (320) is slidably connected to the sliding platform of the vertical sliding mechanism (310) and the sliding direction is horizontal. The first forming mold (330) and the second forming mold (340) are mounted side by side on the extrusion table (320).

7. The FEP tube forming equipment according to claim 1, characterized in that: Both the first molding die (330) and the second molding die (340) are provided with a positioning post (350) in the center, and the positioning post (350) can extend into the FEP tube.

8. The FEP tube forming equipment according to claim 7, characterized in that: The end of the positioning post (350) is frustum-shaped or conical.

9. The FEP tube forming equipment according to claim 1, characterized in that: Both the first molding die (330) and the second molding die (340) are provided with retaining rings (360) on their sides. The retaining rings (360) can close the upper opening of the heating ring (200) to reduce heat loss.

10. A forming method based on the FEP tube forming equipment according to any one of claims 1 to 9, characterized in that, include: The FEP tube to be formed is passed from bottom to top through the bottom of the clamping assembly (100), so that the FEP tube is located between the clamping groove (130) of the first clamping seat (110) and the clamping groove (130) of the second clamping seat (120); Start the clamping drive motor (150) so that the first clamping seat (110) and the second clamping seat (120) together clamp the EEP tube, and the end of the FEP tube is 5-20mm higher than the cylindrical structure; The heating ring (200) is fitted onto the outside of the cylindrical structure; The heating ring (200) is activated, and the heating temperature of the heating ring (200) is set between 280 and 350°C, and the heating time is between 30 and 60 seconds. The vertical sliding mechanism (310) drives the extrusion table (320) to move downward, causing the first forming mold (330) to apply pressure to the end of the FEP tube, and the end of the FEP tube is pressed outward in the first annular groove (331); The vertical sliding mechanism (310) drives the extrusion table (320) to move upward, and the extrusion table (320) switches the second forming mold (340); The vertical sliding mechanism (310) drives the extrusion table (320) to move downward, and drives the second forming mold (340) to apply pressure to the end of the FEP tube. The end of the FEP tube is pressed by the annular pressure strip (3411) in the second annular groove (341) to produce a concave structure, which is shaped for 40 to 60 seconds. The vertical sliding mechanism (310) drives the extrusion table (320) to move upward, removing the heating ring (200), and the clamping drive motor (150) drives the second clamping seat (120) away from the first clamping seat (110), removing the FEP tube from it.

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