Annular four-fluorine steel lining forming tool and forming method

Abstract

This invention provides a molding fixture for annular PTFE steel liners, comprising a molding table, a vacuum pump, an extrusion hood, and a steam generator. The upper surface of the molding table has a recessed molding cavity. The suction end of the vacuum pump is connected to the molding cavity. The extrusion hood is detachably mounted on the upper end of the molding table, facing the molding cavity. Clamping components for fixing the extrusion hood are provided around the molding table. A pre-fabricated PTFE sheet and annular steel liner are clamped between the extrusion hood and the molding table. The steam generator is connected to the inner cavity of the extrusion hood, and steam is introduced into the extrusion hood to heat and extrude the PTFE sheet. The molding cavity exerts negative pressure to draw the heated PTFE sheet, causing the PTFE sheet to adhere tightly to the upper surface of the annular steel liner. The center of the PTFE sheet is recessed and passes through the central hole of the annular steel liner before entering the molding cavity of the molding table, forming an inner flange towards the inner wall of the central hole of the annular steel liner. This solves the problem of difficult flange forming of PTFE sheets and improves molding speed and efficiency.

Description

Technical Field

[0001] This invention relates to the field of annular PTFE steel liner molding technology, specifically to an annular PTFE steel liner molding tooling and molding method. Background Technology

[0002] Annular PTFE steel lining is a type of ring-shaped steel lining formed by covering the surface of a PTFE sheet with a PTFE sheet. It is mainly used in chemical equipment such as reaction units and desulfurization towers as a support component for supporting workpieces such as grating plates and distribution discs.

[0003] In the current manufacturing process of annular PTFE steel liners, due to the lack of suitable molding fixtures, the PTFE sheet is generally heated manually with a handheld torch, and then manually thermoplasticized and folded. This molding method has the disadvantages of difficulty in folding the PTFE sheet during the molding process, as well as slow molding speed and low efficiency. Summary of the Invention

[0004] In view of this, it is necessary to provide a ring-shaped PTFE steel liner forming tool that can improve forming efficiency.

[0005] It is necessary to provide a method for molding annular PTFE steel liners that can improve molding efficiency.

[0006] A forming fixture for annular PTFE steel liners includes a forming table, a vacuum pump, an extrusion hood, and a steam generator. The upper surface of the forming table has a recessed forming cavity. The suction end of the vacuum pump is connected to the forming cavity. The extrusion hood is detachably mounted on the upper end of the forming table, facing the forming cavity. Clamping components for fixing the extrusion hood are provided around the forming table. A pre-fabricated PTFE plate and annular steel liner are clamped between the extrusion hood and the forming table. The steam output end of the steam generator is connected to the inner cavity of the extrusion hood. Steam is introduced into the extrusion hood to heat the PTFE plate and extrude it towards the forming cavity. The forming cavity exerts negative pressure to draw the heated PTFE plate, causing the PTFE plate to adhere tightly to the upper surface of the annular steel liner. The center of the PTFE plate is recessed and passes through the central hole of the annular steel liner before entering the forming cavity of the forming table, forming an inwardly turned edge towards the inner wall of the central hole of the annular steel liner.

[0007] Preferably, it also includes a base, a support frame, a hot-pressed part, a heater, and a drive motor mounted on the base. The forming table is arranged parallel to the base, and the drive motor is axially connected to the forming table and can drive the forming table to rotate parallel to the base. The support frame spans directly above the forming table, and the hot-pressed part and the heater are respectively mounted on the support frame and face the forming table. Lateral fixing members for fixing the annular steel liner are symmetrically arranged around the forming table. After the bottom of the PTFE plate forming the inner flange is opened, it is connected to the annular... The steel liner is simultaneously inverted on the forming table and clamped and fixed by the lateral fixing component. The forming table drives the PTFE plate and the annular steel liner to rotate. The heater heats the side wall of the inner flange of the rotating PTFE plate. The hot pressing forming component can extend into the inner side of the inner flange of the PTFE plate through the opening of the PTFE plate and press the inner flange side wall of the rotating and heated PTFE plate towards the lower surface of the annular steel liner, so that the inner flange of the PTFE plate covers the lower surface of the annular steel liner, thereby performing a second forming of the PTFE plate.

[0008] Preferably, the support frame has an adjustment groove longitudinally formed along its length, and an adjustment arm is vertically arranged in the adjustment groove. The heater is pinned to the lower end of the adjustment arm and can rotate along the adjustment arm. The adjustment arm can drive the heater to move along the opening direction of the adjustment groove to adjust the position of the heater.

[0009] Preferably, the hot-pressed part includes an adjusting sleeve, a lifting arm, a tilting arm, and a forming roller. The adjusting sleeve is installed on the adjusting groove, adjacent to the adjusting arm, and can move freely along the opening direction of the support frame. The lifting arm is vertically inserted into the adjusting sleeve and can move up and down along the adjusting sleeve for adjustment. One end of the tilting arm is hinged to the lower end of the lifting arm, and the other end of the tilting arm extends outward along the lifting arm towards the outside of the forming table and can rotate up and down along the lifting arm. The forming roller is coaxially and rotatably mounted on the tilting arm and close to the end of the tilting arm that is hinged to the lifting arm. When the tilting arm rotates downward, it can drive the forming roller to tilt towards the upper surface of the forming table, pressing the side wall of the heated PTFE sheet with the inner flange towards the lower surface of the annular steel liner to perform a second forming of the PTFE sheet.

[0010] Preferably, each clamping member includes an inverted chamfered arm, a pressure block, and an extrusion screw. The open end of the inverted chamfered arm can clamp the upper edge of the extrusion cover and the lower edge of the forming table. The extrusion screw is longitudinally disposed through one end of the inverted chamfered arm and is threadedly connected to the inverted chamfered arm. The pressure block is disposed at the end of the extrusion screw that penetrates the inner side of the inverted chamfered arm and can abut against the upper edge of the extrusion cover or the lower edge of the forming table. By rotating the extrusion screw, the pressure block is driven to move towards the other end of the inverted chamfered arm to clamp and fix the extrusion cover and the forming table to each other.

[0011] Preferably, each of the lateral fixing components includes a pressure claw, a fixing seat, and an adjusting screw. The fixing seat is disposed on the lower edge of the forming table, and a slot is provided parallel to the radial direction of the outer side wall of the fixing seat facing the forming table. The pressure claw is vertically disposed on the outer side of the forming table, and the lower end of the pressure claw is provided with an insertion part extending towards the slot. The insertion part is matched and inserted into the slot. The upper end of the pressure claw is provided with a clamping part bent towards the center of the forming table. The clamping part is higher than the upper end surface of the forming table. A threaded hole is provided on the side wall of the pressure claw facing the fixing seat. One end of the adjusting screw is rotatably disposed on the fixing seat, and the other end is threadedly connected to the threaded hole. Rotating the adjusting screw can push the pressure claw to move towards the center of the forming table to fix the side wall of the annular steel liner inverted on the forming table.

[0012] Preferably, a first sealing ring is provided on the upper end face of the forming table that contacts the annular steel liner, and the first sealing ring is arranged around the circumference of the forming cavity; a second sealing ring is provided on the circumference of the end face of the extrusion cover that contacts the PTFE plate.

[0013] Preferably, the heater is a hot air gun or a flame gun.

[0014] A method for forming an annular PTFE steel liner, the method being applied to the aforementioned annular PTFE steel liner forming fixture, the method comprising the following steps: S1: Prefabricated PTFE plate and annular steel liner, the surface of the PTFE plate is sodium treated, and the surface of the annular steel liner is coated with adhesive. S2 places the prefabricated annular steel liner parallel to the forming table, stacks the prefabricated PTFE plate on the upper surface of the steel liner, and places the extrusion cover on the PTFE plate. The extrusion cover and the forming table are aligned with each other. Clamping components are installed. Multiple sets of clamping components are arranged along the circumference of the forming table to fix the extrusion cover on the upper end of the forming table. The PTFE plate and the annular steel liner are clamped between the extrusion cover and the PTFE plate. The PTFE plate isolates the inner cavity of the extrusion cover from the forming cavity of the forming table, so that they are not connected to each other. S3: Turn on the steam generator to input high-pressure steam into the extrusion hood; turn on the vacuum pump to perform negative pressure suction on the forming chamber of the forming table, use high-pressure steam to heat and extrude the PTFE plate, causing the PTFE plate to deform towards the forming chamber, use the combination of negative pressure suction and high-pressure steam to perform the first forming of the PTFE plate, causing the middle part of the PTFE plate to deform and be recessed into the forming chamber of the forming table, forming an inner flange towards the inner side wall of the annular steel liner hole, then stop the steam output, and stop the negative pressure suction after the PTFE plate cools and solidifies; S4: Disassemble the extrusion cover, the PTFE plate after the first molding, and the annular steel liner, and cut holes at the bottom of the PTFE plate after the first molding; S5: Flip over the cut-out PTFE plate and annular steel liner, place them upside down on the forming table, with the lower surface of the annular steel liner facing up and pressing it onto the PTFE plate. Install the lateral fixing parts to fix the annular steel liner on the forming table, and turn on the drive to drive the forming table to rotate circumferentially. S6: Turn on the heater to heat the inner flange sidewall at the opening of the PTFE plate, adjust the height of the lifting arm, and rotate the flipping arm upward to make the forming pressure roller stand upright and enter the inner side of the PTFE plate from the opening. After fixing the lifting arm, manually pull the flipping arm downward to change the angle of the forming pressure roller, so that the forming pressure roller squeezes the inner flange sidewall of the heated PTFE plate towards the lower surface of the annular steel liner until the PTFE plate is tightly attached to the lower surface of the annular steel liner, forming a covering on the annular steel liner, and completing the second forming. S7: Install the extrusion cover on the upper part of the PTFE sheet after the second molding, fix it with clamps, and use the extrusion cover to cool and shape the PTFE sheet after the second molding.

[0015] As can be seen from the above technical solution, this application provides a molding fixture for annular PTFE steel liners, including a molding table, a vacuum pump, an extrusion hood, and a steam generator. The upper end face of the molding table is provided with a recessed molding cavity. The suction end of the vacuum pump is connected to the molding cavity. The extrusion hood is detachably mounted on the upper end of the molding table and faces the molding cavity. Clamping components for fixing the extrusion hood are provided around the molding table. The extrusion hood and the molding table are used to clamp a pre-made PTFE plate and annular steel liner. The steam output end of the steam generator is connected to the inner cavity of the extrusion hood. Steam is introduced into the extrusion hood to heat the PTFE plate and extrude it towards the molding cavity. The molding cavity draws the heated PTFE plate under negative pressure, so that the periphery of the PTFE plate is tightly attached to the upper surface of the annular steel liner. The middle part of the PTFE plate is recessed and passes through the central hole of the annular steel liner before entering the molding cavity of the molding table, forming an inward flange towards the inner wall of the central hole of the annular steel liner. By heating and pressurizing with steam, and using negative pressure suction for assistance, PTFE sheets can be quickly flanged and formed, solving the problem of difficult flanging of PTFE sheets and improving forming speed and efficiency. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the assembly structure of the forming table and the extrusion cover.

[0017] Figure 2 This is a schematic diagram of the exploded structure of the forming platform and the extrusion cover.

[0018] Figure 3 This is a side view of the molding platform and base structure.

[0019] Figure 4 This is a schematic diagram of the three-dimensional structure of the molding platform and the base.

[0020] Figure 5A schematic diagram of the secondary molding assembly for the molding platform.

[0021] Figure 6 A schematic diagram showing the state after the molding stage has undergone secondary molding.

[0022] Figure 7 This is a schematic diagram of the clamping component structure.

[0023] Figure 8 This is a schematic diagram of the lateral fixing component structure.

[0024] Figure 9 This is a schematic diagram of the annular steel liner and PTFE plate before molding.

[0025] Figure 10 This is a schematic diagram of the state of the PTFE plate after it has been internally flanged.

[0026] Figure 11 This is a schematic diagram showing the state of the PTFE plate after the bottom hole has been opened.

[0027] Figure 12 This is a schematic diagram showing the state of the PTFE plate and the annular steel liner after secondary molding.

[0028] In the diagram: 1. Forming table; 2. Vacuum pump; 3. Extrusion hood; 4. Steam generator; 5. Forming cavity; 6. Clamping component; 6. C-shaped clamping arm; 61. Pressure block; 62. Extrusion screw; 63. Lateral fixing component; 7. Pressure claw; 71. Fixing seat; 72. Adjusting screw; 73. Slot; 74. Base; 8. Support frame; 9. Hot-pressed part; 10. Heater; 11. Drive motor; 12. Adjusting groove; 91. Adjusting arm; 92. Limiting groove; 93. First adjusting handle; 94. Adjusting sleeve; 101. Lifting arm; 102. Tilting arm; 103. Forming roller; 104. Second adjusting handle; 105. Annular steel liner; 13. PTFE plate; 14. Detailed Implementation

[0029] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Please refer to Figure 1 , 2 , Figure 9 , Figure 10This invention provides a molding fixture for annular PTFE steel liners, including a molding table 1, a vacuum pump 2, an extrusion shroud 3, and a steam generator 4. The upper surface of the molding table 1 has a recessed molding cavity 5. The suction end of the vacuum pump 2 is connected to the molding cavity 5. The inner diameter of the molding cavity 5 is the same as the diameter of the central hole of the pre-fabricated annular steel liner 13. The diameter of the extrusion shroud 3 is the same as the outer diameter of the molding table 1. The extrusion shroud 3 is detachably mounted on the upper end of the molding table 1, facing the molding cavity 5. The extrusion shroud 3 and the molding table 1 are used to clamp the pre-fabricated PTFE sheet. 14 and annular steel liner 13, clamping members 6 for fixing extrusion cover 3 are provided around the forming table 1. The steam output end of the steam generator 4 is connected to the inner cavity of the extrusion cover 3. When forming the annular PTFE steel liner, the pre-made annular steel liner 13 is placed flat on the upper end of the forming table 1 and aligned with the forming cavity 5. The pre-made PTFE plate 14 is stacked parallel on the upper surface of the annular steel liner 13. The PTFE plate 14 and the annular steel liner 13 have the same diameter and are aligned with each other. The outer diameter of the forming table 1 is close to the outer diameter of the annular steel liner 13. The PTFE plate 14 is a whole piece. A pressing shroud 3 is placed on a PTFE plate 14. After the pressing shroud 3 is fixed by clamping members 6, the inner cavity of the pressing shroud 3 is isolated from the forming cavity 5 by the PTFE plate 14, and they are not connected to each other and are in a sealed state from the outside. Steam generator 4 is turned on to introduce steam into the pressing shroud 3. The steam is used to heat the PTFE plate 14, and by pressurizing the introduced steam, the pressure of the steam is used to press the PTFE plate 14 towards the forming cavity 5. The four sides of the PTFE plate 14 are clamped on the annular steel liner 13. After the middle of the PTFE plate 14 is heated, Under steam pressure, the PTFE plate 14 protrudes from the central hole of the annular steel liner 13 towards the forming cavity 5. Simultaneously, the vacuum pump 2 is activated to create negative pressure suction in the forming cavity 5, exerting a downward force on the PTFE plate 14 to assist in its deformation. Ultimately, the PTFE plate 14 is tightly pressed against the upper surface of the annular steel liner 13, and its center protrudes into the central hole of the annular steel liner 13, entering the forming cavity 5 of the forming table 1. It then forms an inward flange towards the inner wall of the central hole of the annular steel liner 13. At this point, steam output is stopped, and the PTFE plate 14 is allowed to cool and solidify. This forming fixture uses steam to heat and pressurize the PTFE plate 14, and uses negative pressure suction for assistance, enabling the PTFE plate 14 to quickly flange towards the inner side of the central hole of the annular steel liner 13. This solves the problem of difficult flange forming of the PTFE plate 14 and improves the forming speed and efficiency.

[0031] Please refer to Figures 3 to 6 ,as well as Figure 11 and Figure 12Furthermore, the annular PTFE steel liner forming fixture also includes a base 8, a support frame 9, a hot-press forming part 10, a heater 11, and a drive motor 12 mounted on the base 8. The forming platform 1 is arranged parallel to the base 8, and the drive motor 12 is located below the forming platform 1 and is axially connected to the forming platform 1. The drive motor 12 is preferably a servo motor, used to drive the forming platform 1 to rotate parallel to the base 8. The support frame 9 is a U-shaped gantry frame body, spanning directly above the forming platform 1. Both ends of the support frame 9 are fixed to the base 8. The hot-press forming part 10 and the heater 11 are respectively mounted on the support frame 9 and face the forming platform 1. The heater 11 is selected as a hot air gun or a flame gun, used to heat the PTFE sheet 14 after flanging. The hot-press forming part 10 is located on one side of the heater 11, used to hot-press and shape the heated PTFE sheet 14. Lateral fixing parts 7 for fixing the annular steel liner 13 are symmetrically arranged around the forming platform 1.

[0032] During implementation, after the PTFE plate 14 has been formed, cooled, and shaped, the extrusion cover 3 is removed. Simultaneously, the PTFE plate 14 and the annular steel liner 13 are flipped and placed upside down on the forming table 1, with the lower surface of the annular steel liner 13 facing upwards and pressed onto the PTFE plate 14. The annular steel liner 13 is clamped and fixed around its outer edges using the lateral fixing pieces 7. At this time, a hole is manually made at the bottom of the flanged PTFE plate 14 using a cutting machine or hole opener. After making the hole, the angle of the heater 11 is adjusted so that it heats the inner flanged sidewall of the PTFE plate 14 at the opening. The drive motor 12 is then activated. The forming table 1 rotates to drive the PTFE plate 14 and the annular steel liner 13 to rotate synchronously. The heater 11 heats the inner flange sidewall of the rotating PTFE plate 14. The hot-pressed forming part 10 can extend into the inner side of the inner flange of the PTFE plate 14 from the opening of the PTFE plate 14, and press the inner flange of the rotating and heated PTFE plate 14 towards the outer side of the annular steel liner 13, and gradually flip it towards the lower surface of the annular steel liner 13, so that the inner flange of the PTFE plate 14 covers the lower surface of the annular steel liner 13, so as to perform a second forming of the PTFE plate 14.

[0033] Specifically, the upper end face of the support frame 9 has a through adjustment groove 91 extending longitudinally along its length. A limiting groove 93 communicating with the adjustment groove 91 is provided laterally along the length of the side wall of the support frame 9. A first adjustment handle 94 is provided on the limiting groove 93. An adjustment arm 92 is vertically arranged inside the adjustment groove 91. The first adjustment handle 94 passes through the adjustment groove 91 and is threadedly connected to the upper end of the adjustment arm 92. The lower end of the adjustment arm 92 extends towards the forming table 1. The heater 11 is pinned to the lower end of the adjustment arm 92 and can rotate along the adjustment arm 92 to adjust the angle of the heater 11. The adjustment arm 92 drives the heater 11 to rotate along the first adjustment handle 94 and can move along the opening direction of the adjustment groove 91 to adjust the position of the heater 11, so that the heating port of the heater 11 faces the inner flange sidewall of the opening of the PTFE plate 14 for heating.

[0034] The hot-pressed part 10 includes an adjusting sleeve 101, a lifting arm 102, a tilting arm 103, and a forming roller 104. The adjusting sleeve 101 is vertically mounted on the adjusting groove 91, adjacent to the adjusting arm 92, and facing the forming table 1. It can move freely along the length of the support frame 9. The lifting arm 102 is vertically inserted into the adjusting sleeve 101 and can be adjusted up and down along the adjusting sleeve 101. A second adjusting handle 105 is provided on the outer wall of the adjusting sleeve 101. The second adjusting handle 105 passes through the inner cavity of the adjusting sleeve 101 and is threadedly connected to the adjusting sleeve 101 to lock the position of the lifting arm 102. One end of the tilting arm 103 is hinged to the lower end of the lifting arm 102, and the other end of the tilting arm 103... One end extends outward from the lifting arm 102 towards the forming table 1 and can rotate up and down along the lifting arm 102. The forming roller 104 is coaxially and rotatably mounted on the flipping arm 103 and close to the end of the flipping arm 103 that is hinged to the lifting arm 102. In use, the height and lateral position of the lifting arm 102 can be adjusted so that the forming roller 104 is located inside the inner flange of the PTFE plate 14. Then, by manually operating the flipping arm 103 to flip towards the upper end face of the forming table 1, the forming roller 104 pushes the side wall of the heated PTFE plate 14 towards the lower surface of the annular steel liner 13 and presses it tightly against the lower surface of the annular steel liner 13, so that the PTFE plate 14 covers the annular steel liner 13, completing the second forming of the PTFE plate 14. The forming roller 104 has a conical structure, with a smaller end facing the lifting arm 102 and a larger end facing outward from the forming table 1.

[0035] In actual operation, one end of the flip arm 103 extending outward toward the forming table 1 can be passed through the adjustment groove 91 of the support frame 9, so that the flip arm 103 can slide up and down along the limiting groove 93 when rotating. When the flip arm 103 drives the forming pressure roller 104 to press toward the lower surface of the annular steel liner 13, the support frame 9 provides lateral support for the flip arm 103, which can improve the stability of the flip arm 103 and prevent the flip arm 103 from swinging left and right.

[0036] Please refer to Figure 1 and Figure 7 The clamping components 6 are in multiple sets and are detachably installed with the forming table 1. Each clamping component 6 includes a chamfered clamping arm 61, a pressure block 62, and an extrusion screw 63. The open end of the chamfered clamping arm 61 can clamp the upper edge of the extrusion cover 3 and the lower edge of the forming table 1. The extrusion screw 63 is longitudinally disposed through one end of the chamfered clamping arm 61 and is threadedly connected to the chamfered clamping arm 61. The pressure block 62 is disposed at the end of the extrusion screw 63 that passes through the inner side of the chamfered clamping arm 61 and can abut against the upper edge of the extrusion cover 3 or the lower edge of the forming table 1. During installation, the chamfered clamping arm 61 is clamped on the edges of the extrusion cover 3 and the forming table 1. By rotating the extrusion screw 63, the pressure block 62 is driven to move towards the other end of the chamfered clamping arm 61 to clamp and fix the extrusion cover 3 and the forming table 1 to each other.

[0037] Please refer to Figure 5 and Figure 8 The lateral fixing members 7 are in multiple sets, symmetrically arranged around the perimeter of the forming table 1. Each lateral fixing member 7 includes a pressure claw 71, a fixing seat 72, and an adjusting screw 73. The fixing seat 72 is located on the lower edge of the forming table 1, and a slot 74 is opened parallel to the outer side of the outer wall of the fixing seat 72 in the radial direction towards the forming table 1. The pressure claw 71 is vertically arranged on the outer side of the forming table 1, and the lower end of the pressure claw 71 is provided with a plug-in part extending towards the slot 74. The plug-in part matches and plugs into the slot 74, and can be adjusted along the opening direction of the slot 74. The upper end of the pressure claw 71, which is telescopically movable, is provided with a clamping part that bends towards the center of the forming table 1. The clamping part is higher than the upper surface of the forming table 1. A threaded hole is opened on the side wall of the pressure claw 71 facing the fixed seat 72. One end of the adjusting screw 73 is rotatably mounted on the fixed seat 72, and the other end is threadedly connected to the threaded hole. Rotating the adjusting screw 73 can push the pressure claw 71 to move along the slot 74 towards the center of the forming table 1, which is used to fix the side wall of the annular steel liner 13 inverted on the forming table 1. When fixing, by rotating the adjusting screws 73 on opposite sides of the forming table 1, a mutual compressive force is formed on the annular steel liner 13 inverted on the forming table 1, clamping the annular steel liner 13 on the forming table 1. The side wall of the annular steel liner 13 is clamped and fixed by the lateral fixing member 7, which can completely expose the lower surface of the annular steel liner 13, so that the forming pressure roller 104 can compress and cover the PTFE plate 14.

[0038] Furthermore, to improve the sealing between the molding cavity 5 and the extrusion cover 3 and the annular steel liner 13 and the PTFE plate 14, a first sealing ring is provided on the upper end face of the molding table 1 where it contacts the annular steel liner 13, and the first sealing ring is arranged around the circumference of the molding cavity 5; a second sealing ring is arranged around the end face of the extrusion cover 3 where it contacts the PTFE plate 14. Both the first sealing ring and the second sealing ring are made of rubber.

[0039] The invention also provides a method for forming an annular PTFE steel liner, which is applied to the above-mentioned annular PTFE steel liner forming tooling. The method includes the following steps: S1: Prefabricate PTFE plate 14 and annular steel liner 13, perform sodium treatment on the surface of PTFE plate 14, and apply adhesive to the surface of annular steel liner 13. S2 places the prefabricated annular steel liner 13 parallel on the forming table 1, stacks the prefabricated PTFE plate 14 on the upper surface of the steel liner, and covers the PTFE plate 14 with the extrusion cover 3. The extrusion cover 3 and the forming table 1 are aligned with each other. The clamping member 6 is installed. Multiple sets of clamping members 6 are arranged along the circumference of the forming table 1 to fix the extrusion cover 3 at the upper end of the forming table 1. The PTFE plate 14 and the annular steel liner 13 are clamped between the extrusion cover 3 and the PTFE plate 14. The PTFE plate 14 isolates the inner cavity of the extrusion cover 3 from the forming cavity 5 of the forming table 1, so that they are not connected to each other. S3: Turn on the steam generator 4 to input high-pressure steam into the extrusion hood 3; turn on the vacuum pump 2 to perform negative pressure suction on the forming cavity 5 of the forming table 1, use high-pressure steam to heat and extrude the PTFE plate 14, causing the PTFE plate 14 to deform towards the forming cavity 5, use the combination of negative pressure suction and high-pressure steam to perform the first forming of the PTFE plate 14, causing the middle part of the PTFE plate 14 to deform and be recessed into the forming cavity 5 of the forming table 1, and after forming an inner flange towards the inner side wall of the hole in the annular steel liner 13, stop the steam output, and stop the negative pressure suction after the PTFE plate 14 cools and solidifies; S4: Disassemble the extrusion cover 3, the PTFE plate 14 after the first molding, and the annular steel liner 13, and cut holes at the bottom of the PTFE plate 14 after the first molding. S5: Flip over the cut-out PTFE plate 14 and annular steel liner 13, place them upside down on the forming table 1, with the lower surface of the annular steel liner 13 facing upwards and pressing it onto the PTFE plate 14. Install the lateral fixing piece 7 to fix the annular steel liner 13 on the forming table 1, and turn on the drive motor 12 to drive the forming table 1 to rotate circumferentially. S6: Turn on the heater 11 to heat the inner flange sidewall at the opening of the PTFE plate 14, adjust the height of the lifting arm 102, and rotate the flipping arm 103 upward to make the forming roller 104 stand upright and enter the inner side of the PTFE plate 14 from the opening. After fixing the lifting arm 102, manually pull the flipping arm 103 downward to change the angle of the forming roller 104, so that the forming roller 104 presses the inner flange sidewall of the heated PTFE plate 14 toward the lower surface of the annular steel liner 13 until the PTFE plate 14 is tightly attached to the lower surface of the annular steel liner 13, forming a covering on the annular steel liner 13, and completing the second forming. S7: Install the extrusion cover 3 on the upper end of the PTFE plate 14 after the second molding, and fix it with the clamping part 6. Use the extrusion cover 3 to cool and shape the PTFE plate 14 after the second molding.

[0040] This method for forming annular PTFE steel liners utilizes steam to heat and pressurize the PTFE plate 14, and uses negative pressure suction for assistance, enabling the PTFE plate 14 to be quickly flanged into the inner side of the central hole of the annular steel liner 13. This solves the problem of difficult flanging of the PTFE plate 14 and improves the forming speed and efficiency.

[0041] The above-disclosed embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of the invention. Those skilled in the art will understand that implementing all or part of the above-described embodiments and making equivalent changes in accordance with the claims of the present invention are still within the scope of the invention.

Claims

1. A tooling for forming annular PTFE steel liners, characterized in that: The device includes a forming platform, a vacuum pump, an extrusion shroud, and a steam generator. The upper surface of the forming platform has a recessed forming cavity. The suction end of the vacuum pump is connected to the forming cavity. The extrusion shroud is detachably mounted on the upper surface of the forming platform, directly facing the forming cavity. Clamping components for fixing the extrusion shroud are provided around the forming platform. A pre-fabricated PTFE plate and an annular steel liner are clamped between the extrusion shroud and the forming platform. The steam output end of the steam generator is connected to the inner cavity of the extrusion shroud. Steam is introduced into the extrusion shroud to heat the PTFE plate and extrude it towards the forming cavity. The forming cavity exerts negative pressure to draw the heated PTFE plate, causing the PTFE plate to adhere tightly to the upper surface of the annular steel liner. The center of the PTFE plate is recessed and passes through the central hole of the annular steel liner before entering the forming platform. Inside the cavity, an inwardly flanged edge is formed towards the inner wall of the annular steel liner's central hole. The system also includes a base, a support frame, a hot-pressed component, a heater, and a drive motor mounted on the base. The forming platform is parallel to the base, and the drive motor is axially connected to the forming platform, enabling it to rotate parallel to the base. The support frame spans directly above the forming platform. The hot-pressed component and heater are respectively mounted on the support frame, facing the forming platform. Lateral fixing components for securing the annular steel liner are symmetrically arranged around the forming platform. After the bottom of the PTFE plate forming the inwardly flanged edge is perforated, it is inverted on the forming platform simultaneously with the annular steel liner, clamped and fixed by the lateral fixing components. The forming platform drives the PTFE plate and the annular steel liner to rotate. The heater... The sidewall of the inner flange of the rotating PTFE sheet is heated. The hot-pressed forming part can extend into the inner side of the inner flange of the PTFE sheet through the opening of the PTFE sheet, and press the inner flange sidewall of the rotating and heated PTFE sheet towards the lower surface of the annular steel liner, so that the inner flange of the PTFE sheet covers the lower surface of the annular steel liner, thereby performing a second forming of the PTFE sheet; the support frame has an adjustment groove longitudinally opened along its length direction, and an adjustment arm is vertically arranged in the adjustment groove. The heater is pinned to the lower end of the adjustment arm and can rotate along the adjustment arm. The adjustment arm can drive the heater to move along the opening direction of the adjustment groove to adjust the position of the heater; the hot-pressed forming part includes an adjustment sleeve, a lifting arm, and a flipping... The rotating arm and forming roller are arranged as follows: the adjusting sleeve is installed on the adjusting groove, adjacent to the adjusting arm, and can move freely along the opening direction of the support frame; the lifting arm is vertically inserted on the adjusting sleeve and can move up and down along the adjusting sleeve for adjustment; one end of the flipping arm is hinged to the lower end of the lifting arm, and the other end of the flipping arm extends outward along the lifting arm towards the outside of the forming table and can rotate up and down along the lifting arm; the forming roller is coaxially and rotatably mounted on the flipping arm and close to the end of the flipping arm that is hinged to the lifting arm; the downward rotation of the flipping arm can drive the forming roller to flip towards the upper end face of the forming table, pressing the side wall of the heated PTFE sheet with the inner flange towards the lower surface of the annular steel liner to perform a second forming of the PTFE sheet.

2. The annular PTFE steel liner forming tooling as described in claim 1, characterized in that: Each clamping component includes an inverted chamfered arm, a pressure block, and an extrusion screw. The open end of the inverted chamfered arm can clamp the upper edge of the extrusion cover and the lower edge of the forming table. The extrusion screw is longitudinally inserted through one end of the inverted chamfered arm and is threadedly connected to the inverted chamfered arm. The pressure block is located at the end of the extrusion screw that enters the inner side of the inverted chamfered arm and can abut against the upper edge of the extrusion cover or the lower edge of the forming table. By rotating the extrusion screw, the pressure block is driven to move towards the other end of the inverted chamfered arm to clamp and fix the extrusion cover and the forming table to each other.

3. The annular PTFE steel liner forming tooling as described in claim 1, characterized in that: Each of the lateral fixing components includes a pressure claw, a fixing seat, and an adjusting screw. The fixing seat is disposed on the lower edge of the forming table, and a slot is provided parallel to the radial direction of the outer side wall of the fixing seat facing the forming table. The pressure claw is vertically disposed on the outer side of the forming table, and the lower end of the pressure claw is provided with a plug-in portion extending towards the slot. The plug-in portion is matched and plugged into the slot. The upper end of the pressure claw is provided with a clamping portion bent towards the center of the forming table. The clamping portion is higher than the upper end surface of the forming table. A threaded hole is provided on the side wall of the pressure claw facing the fixing seat. One end of the adjusting screw is rotatably disposed on the fixing seat, and the other end is threadedly connected to the threaded hole. Rotating the adjusting screw can push the pressure claw to move towards the center of the forming table to fix the side wall of the annular steel liner inverted on the forming table.

4. The annular PTFE steel liner forming tooling as described in claim 1, characterized in that: A first sealing ring is provided on the upper end face of the forming table that contacts the annular steel liner, and the first sealing ring is arranged around the circumference of the forming cavity; a second sealing ring is provided on the circumference of the end face of the extrusion cover that contacts the PTFE plate.

5. The annular PTFE steel liner forming tooling as described in claim 1, characterized in that: The heater is a hot air gun or a flame gun.

6. A method for forming an annular PTFE steel liner, characterized in that: This method is applied to the annular PTFE steel liner forming tooling as described in any one of claims 1 to 5, and the method includes the following steps: S1: Prefabricated PTFE plate and annular steel liner, the surface of the PTFE plate is sodium treated, and the surface of the annular steel liner is coated with adhesive. S2 places the prefabricated annular steel liner parallel to the forming table, stacks the prefabricated PTFE plate on the upper surface of the steel liner, and places the extrusion cover on the PTFE plate. The extrusion cover and the forming table are aligned with each other. Clamping components are installed. Multiple sets of clamping components are arranged along the circumference of the forming table to fix the extrusion cover on the upper end of the forming table. The PTFE plate and the annular steel liner are clamped between the extrusion cover and the PTFE plate. The PTFE plate isolates the inner cavity of the extrusion cover from the forming cavity of the forming table, so that they are not connected to each other. S3: Turn on the steam generator to input high-pressure steam into the extrusion hood; turn on the vacuum pump to perform negative pressure suction on the forming chamber of the forming table, use high-pressure steam to heat and extrude the PTFE plate, causing the PTFE plate to deform towards the forming chamber, use the combination of negative pressure suction and high-pressure steam to perform the first forming of the PTFE plate, causing the middle part of the PTFE plate to deform and be recessed into the forming chamber of the forming table, forming an inner flange towards the inner side wall of the annular steel liner hole, then stop the steam output, and stop the negative pressure suction after the PTFE plate cools and solidifies; S4: Disassemble the extrusion cover, the PTFE plate after the first molding, and the annular steel liner, and cut holes at the bottom of the PTFE plate after the first molding; S5: Flip over the cut-out PTFE plate and annular steel liner, place them upside down on the forming table, with the lower surface of the annular steel liner facing up and pressing it onto the PTFE plate. Install the lateral fixing parts to fix the annular steel liner on the forming table, and turn on the drive to drive the forming table to rotate circumferentially. S6: Turn on the heater to heat the inner flange sidewall at the opening of the PTFE plate, adjust the height of the lifting arm, and rotate the flipping arm upward to make the forming pressure roller stand upright and enter the inner side of the PTFE plate from the opening. After fixing the lifting arm, manually pull the flipping arm downward to change the angle of the forming pressure roller, so that the forming pressure roller squeezes the inner flange sidewall of the heated PTFE plate towards the lower surface of the annular steel liner until the PTFE plate is tightly attached to the lower surface of the annular steel liner, forming a covering on the annular steel liner, and completing the second forming. S7: Install the extrusion cover on the upper part of the PTFE sheet after the second molding, fix it with clamps, and use the extrusion cover to cool and shape the PTFE sheet after the second molding.

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