Fusion welding machine for soluble polytetrafluoroethylene tube plate and use method of fusion welding machine

Abstract

The invention provides a fusion welding machine for a soluble polytetrafluoroethylene tube plate and a using method of the fusion welding machine, and belongs to the technical field of welding. The problem that existing PFA welding equipment is not suitable for tube plate welding is solved. The fusion welding machine comprises an operation table, a sliding support, a fixing frame, a top column assembly, a lower die disc, a material pressing disc, a hanging frame, a hot air gun, an upper die assembly, a heat source outer sleeve and a heat source core sleeve, a lower guide rail is arranged on the operation table, the sliding support is slidably connected with the lower guide rail, an upper sliding rail is arranged below a cross beam of the sliding support, and the fixing frame is slidably connected with the upper sliding rail. A first motor is arranged on the fixing frame, the output end of the first motor is connected with a first lead screw, the first lead screw is connected with a hanging bracket, a second motor is arranged on the hanging bracket, the second motor is connected with a second lead screw, the second lead screw is in threaded connection with the hanging bracket, the lower end of the second lead screw is connected with the upper die assembly, and the hot air gun and the heat source jacket are both connected with the hanging bracket. The fusion welding device is mainly used for fusion welding of soluble polytetrafluoroethylene tube plates.

Description

Technical Field

[0001] The present invention belongs to the technical field of welding, and particularly relates to a welding machine for a soluble polytetrafluoroethylene tube sheet and a using method thereof. Background Art

[0002] As a component for fixing both sides of a glass tube, the tube sheet not only requires a certain supporting force, but also needs to be resistant to high temperature and corrosion in process gas, and needs to be closely matched with the glass tube. The tube sheet is one of the core components of a glass tube heat exchanger. The tube sheet is formed by welding a perforated plate and tubes, and the material is soluble polytetrafluoroethylene. Soluble polytetrafluoroethylene is also called PFA. The tube sheet requires firm welding, good sealing performance, and small dimensional deviation after welding. There are two types of conventional PFA welding equipment: hot melt welding equipment and hot pressing welding equipment.

[0003] The hot melt welding equipment uses a heat source to heat the tetrafluoroethylene plate to the melting point to form a molten pool, and then adds different fillers into the molten pool for welding. This welding method is suitable for tetrafluoroethylene plates with larger thickness, and the welding strength is also relatively high, but fillers are required, the welding process operation is complex, and the cost is relatively high.

[0004] The hot pressing welding equipment realizes welding by the dual action of heating and pressure, so that the molecules between the plates penetrate and diffuse with each other. The advantages of hot pressing welding are high welding strength and good sealing performance, and no filling material is required during the welding process, but the requirements for the welding equipment are relatively high.

[0005] The PFA tube sheet is formed by welding a perforated plate and tubes. The tubes perpendicular to the perforated plate are welded in the inner holes of the perforated plate, and the outer walls of the tubes are welded to the inner holes of the perforated plate. Traditional welding equipment is mainly suitable for butt welding or lap welding of "plate to plate" or "tube to tube". Due to the unique structure of the PFA tube sheet, conventional welding equipment is not suitable for welding the tube sheet, and the equipment structure and process cannot well control parameters such as temperature, pressure, and cooling time, resulting in quality problems such as insecure welding, poor sealing performance, or large dimensional deviation after welding, thus affecting the service life of the glass tube heat exchanger, and in severe cases, causing the equipment to stop running, resulting in a large amount of losses. Summary of the Invention

[0006] In view of this, the present invention aims to provide a welding machine for a soluble polytetrafluoroethylene tube sheet and a using method thereof to solve the problem that the existing PFA welding equipment is not suitable for welding the tube sheet.

[0007] To achieve the above object, the present invention adopts the following technical solutions: A welding machine for a soluble polytetrafluoroethylene tube sheet, which includes an operating table, a sliding bracket, a fixing bracket, a top column assembly, a lower die plate, a pressure plate, a hanging bracket, a hot air gun, an upper die assembly, a heat source outer sleeve and a heat source inner sleeve. A lower guide rail is provided on the operating table, the sliding bracket is slidably connected to the lower guide rail, an upper slide rail is provided below the cross beam of the sliding bracket, the fixing bracket is slidably connected to the upper slide rail, a first motor is provided on the fixing bracket, the output end of the first motor is connected to a first lead screw, the first lead screw is connected to the hanging bracket, a second motor is provided on the hanging bracket, the second motor is connected to a second lead screw, the second lead screw is threadedly connected to the hanging bracket, the lower end of the second lead screw is connected to the upper die assembly, both the hot air gun and the heat source outer sleeve are connected to the hanging bracket, an air inlet is provided on the heat source outer sleeve, the air outlet of the hot air gun is connected to the air inlet of the heat source outer sleeve, the heat source inner sleeve is arranged between the upper die assembly and the heat source outer sleeve, the heat source inner sleeve is connected to a pressure rod, the pressure rod is connected to a first cylinder, the lower parts of both the heat source outer sleeve and the heat source inner sleeve are of a conical structure, and the gap between the lower parts of the heat source outer sleeve and the heat source inner sleeve is the hot air outlet. The pressure plate is arranged at the lower end of the hanging bracket, the lower die plate is arranged on the operating table, a plurality of die holes are provided on the lower die plate, a plurality of top columns are provided on the top column assembly, the positions of the plurality of top columns and the plurality of die holes correspond one by one, and the lower part of the top column assembly is connected to a second cylinder.

[0008] Furthermore, cooling channels are provided on both the pressure plate and the lower die plate, and cooling water is introduced into the cooling channels.

[0009] Furthermore, the pressure plate includes a pressure plate and pressure columns. The pressure plate is connected to the hanging bracket, and the number of pressure columns is multiple. The multiple pressure columns are arranged below the pressure plate.

[0010] Furthermore, spiral guide protrusions are provided on the outer side of the heat source inner sleeve.

[0011] Furthermore, the bottom end of the upper die assembly is of an arc cone surface structure.

[0012] Furthermore, the hanging bracket is slidably connected to the fixing bracket.

[0013] Furthermore, the second motor is connected to the second lead screw through a transmission mechanism.

[0014] Furthermore, the number of pressure rods is two, and the two pressure rods are respectively connected to the heat source inner sleeve and the first cylinder.

[0015] Furthermore, the lower part of the top column assembly is connected to a top rod, and the top rod is connected to the second cylinder.

[0016] The present invention also provides a method for using a welding machine for a soluble polytetrafluoroethylene tube sheet, which comprises the following steps:

[0017] Step 1: Start the second cylinder, push the ejector rod assembly upward so that the ejector rod enters the die holes of the lower die plate. Place PFA tubes in all the die holes, place the PFA perforated plate on the lower die plate according to the position, press the PFA perforated plate tightly through the pressure plate, and push the ejector rod assembly upward to push the PFA tubes upward to the height required for fusion welding.

[0018] Step 2: Adjust the position of the hanger, start the hot air gun, and heat the heating part through the hot air outlet. Locally heat the PFA tubes and the PFA perforated plate to the fusion welding temperature. When the molten state starts to appear, start the second motor to drive the upper die assembly to move downward, apply a vertical pressure to the melted part, and rotate in the tangential direction at the same time to achieve spinning fusion welding. Wait for the welded part to cool to the set temperature to complete the fusion welding of one PFA tube and the PFA perforated plate.

[0019] Step 3: After repeating Step 2 to complete the fusion welding of all PFA tubes and PFA perforated plates, start the first motor to separate the pressure plate from the PFA perforated plate, start the second cylinder, and push the tube sheet out of the lower die plate through the ejector rod assembly to complete the fusion welding of the tube sheet.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows: The present invention provides a welding machine for a soluble polytetrafluoroethylene tube sheet and its using method. Adopting the spinning fusion welding method, by controlling parameters such as the welding temperature, pressure, and cooling time, the welding quality of the tube sheet is ensured, and quality problems such as insecure welding, poor sealing, and large dimensional deviation after welding of the tube sheet are avoided.

[0021] In the process of realizing the welding of the tube sheet, the present invention adopts the spinning method for fusion welding. Through structural constraints, the welding deformation of the tube sheet is effectively prevented, and the welding dimensional deviation is reduced; by adjusting the heat flow rate, welding time, and cooling time, the welding strength and sealing performance are ensured. The whole machine can be intelligently controlled. Only the PFA tubes and PFA perforated plates need to be manually placed, and all other welding work is automatically completed. One cycle can complete the welding of 72 tubes, improving the welding efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The accompanying drawings that form a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention. In the drawings:

[0023] Figure 1 is a partial cross-sectional structural schematic diagram of a welding machine for a soluble polytetrafluoroethylene tube sheet according to the present invention;

[0024] Figure 2 The Figure 1 Schematic diagram of the A-A sectional structure in

[0025] Figure 3 The Figure 2 Schematic diagram of the enlarged structure at A in

[0026] Figure 4 The Figure 3 Schematic diagram of the B-B sectional structure in

[0027] Figure 5 Front view structural schematic diagram of the lower die plate of the present invention;

[0028] Figure 6 Top view structural schematic diagram of the lower die plate of the present invention;

[0029] Figure 7 Front view structural schematic diagram of the pressure plate of the present invention;

[0030] Figure 8 Top view structural schematic diagram of the pressure plate of the present invention;

[0031] Figure 9 Schematic diagram of the sectional structure of the upper die assembly of the present invention;

[0032] Figure 10 Schematic diagram of the sectional structure of the heat source core sleeve of the present invention;

[0033] Figure 11 Front view structural schematic diagram of a welding machine for soluble polytetrafluoroethylene tube plates of the present invention;

[0034] Figure 12 Left view structural schematic diagram of a welding machine for soluble polytetrafluoroethylene tube plates of the present invention.

[0035] In the figure:

[0036] 1 - Operating table, 2 - Lower guide rail, 3 - Sliding bracket, 4 - First motor, 5 - Fixed bracket, 6 - First lead screw, 7 - Transmission mechanism, 8 - Second motor, 9 - Second cylinder, 10 - Ejector rod, 11 - Ejector column assembly, 12 - Lower die plate, 13 - Pressure plate, 14 - First cylinder, 15 - Hanging bracket, 16 - Upper slide rail, 17 - Hot air gun, 18 - Second lead screw, 19 - Upper die assembly, 20 - Heat source outer sleeve, 21 - Heat source core sleeve, 22 - Pressure rod, 23 - Die hole, 24 - Cooling channel, 25 - Pressure plate, 26 - Pressure column, 27 - Arc conical surface, 28 - Spiral guide protrusion. Detailed implementation manners

[0037] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments may be combined with each other. The described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments.

[0038] Refer to Figures 1 - 12 Describing this embodiment, a welding machine for a soluble polytetrafluoroethylene tube sheet includes an operation table 1, a sliding bracket 3, a fixed bracket 5, a top column assembly 11, a lower mold plate 12, a pressure plate 13, a hanging bracket 15, a hot air gun 17, an upper mold assembly 19, a heat source outer sleeve 20, and a heat source core sleeve 21.

[0039] A lower guide rail 2 is provided on the operation table 1. The sliding bracket 3 is slidably connected to the lower guide rail 2. An upper slide rail 16 is provided below the cross beam of the sliding bracket 3. The fixed bracket 5 is slidably connected to the upper slide rail 16. Through the cooperation of the lower guide rail 2 and the upper slide rail 16, the position of the fixed bracket 5 in the horizontal direction of the operation table 1 can be moved.

[0040] A first motor 4 is provided on the fixed bracket 5. The output end of the first motor 4 is connected to a first lead screw 6. The first lead screw 6 is connected to the hanging bracket 15. By rotating the first motor 4 to drive the first lead screw 6 to rotate, the hanging bracket 15 is driven to move vertically up and down in the vertical direction.

[0041] A second motor 8 is provided on the hanging bracket 15. The second motor 8 is connected to a second lead screw 18. The second lead screw 18 is threadedly connected to the hanging bracket 15. The lower end of the second lead screw 18 is connected to the upper mold assembly 19. By driving the second lead screw 18 to rotate by the second motor 8, the upper mold assembly 19 is driven to rotate and move vertically up and down in the vertical direction at the same time.

[0042] The hot air gun 17 and the heat source outer sleeve 20 are both connected to the hanging bracket 15. An air inlet is provided on the heat source outer sleeve 20. The air outlet of the hot air gun 17 is connected to the air inlet of the heat source outer sleeve 20. The heat source core sleeve 21 is arranged between the upper die assembly 19 and the heat source outer sleeve 20. The heat source core sleeve 21 is connected to the pressure rod 22, and the pressure rod 22 is connected to the first cylinder 14. The lower parts of the heat source outer sleeve 20 and the heat source core sleeve 21 are both of a conical structure, and the gap between the lower parts of the heat source outer sleeve 20 and the heat source core sleeve 21 is the hot air outlet. The heat source core sleeve 21 is located inside the heat source outer sleeve 20, and the upper die assembly 19 is located inside the heat source core sleeve 21. The hot air generated by the hot air gun 17 enters between the heat source outer sleeve 20 and the heat source core sleeve 21 through the air inlet of the heat source outer sleeve 20. When the first cylinder 14 is started, the first cylinder 14 drives the pressure rod 22 to move up and down, thereby driving the heat source core sleeve 21 to move vertically up and down. By the vertical movement of the heat source core sleeve 21, the opening and closing size of the gap between the lower parts of the heat source outer sleeve 20 and the heat source core sleeve 21 is changed, so as to change the hot air density. The pressure plate 13 is arranged at the lower end of the hanging bracket 15, and the pressure plate 13 moves together with the hanging bracket 15.

[0043] The lower die plate 12 is arranged on the operation table 1. A plurality of die holes 23 are provided on the lower die plate 12. A plurality of ejector pins are arranged on the ejector pin assembly 11. The positions of the plurality of ejector pins and the plurality of die holes 23 correspond one by one. The lower part of the ejector pin assembly 11 is connected to the second cylinder 9. When the second cylinder 9 is started, it drives the ejector pin assembly 11 to move up and down, so that the ejector pins move up and down inside the die holes 23 of the lower die plate 12.

[0044] In this embodiment, cooling channels 24 are provided on both the pressure plate 13 and the lower die plate 12, and cooling water is introduced into the cooling channels 24. The pressure plate 13 and the lower die plate 12 are cooled by the cooling water, so as to cool the fusion welding part.

[0045] The pressure plate 13 in this embodiment includes a pressure plate 25 and a plurality of pressure columns 26. The pressure plate 25 is connected to the hanging bracket 15, and the number of the pressure columns 26 is multiple. The multiple pressure columns 26 are arranged below the pressure plate 25. The PFA porous plate is pressed tightly by the multiple pressure columns 26 to ensure uniform pressure.

[0046] A spiral diversion protrusion 28 is arranged on the outer side of the heat source core sleeve 21 in this embodiment. The hot air is diverted by the spiral diversion protrusion 28, so that the hot air rotates and then heats the heating part, achieving the effect of heat concentration.

[0047] The bottom end of the upper die assembly 19 in this embodiment is of an arc cone surface 27 structure. The arc cone surface 27 can conduct angle guidance on the fusion welding part to ensure the fusion welding accuracy. The hanging bracket 15 is slidably connected to the fixed bracket 5, and the movement of the hanging bracket 15 in the vertical direction is guided by the fixed bracket 5.

[0048] Preferably, the second motor 8 is connected to the second lead screw 18 through a transmission mechanism 7. The number of the pressure rods 22 is two, and the two pressure rods 22 are respectively connected to the heat source core sleeve 21 and the first cylinder 14. The lower part of the ejector pin assembly 11 is connected to an ejector rod 10, and the ejector rod 10 is connected to the second cylinder 9. This ensures stable connection.

[0049] This embodiment is a method of using a welding machine for a soluble polytetrafluoroethylene tube sheet, which includes the following steps:

[0050] Step 1: Start the second cylinder 9 to push the ejector pin assembly 11 upward, so that the ejector pins enter the die holes 23 of the lower die plate 12 and reach the specified height. PFA tubes are placed in all the die holes 23, and 72 tubes can be placed at a time. Place the PFA perforated plate on the lower die plate 12 according to the position, press the PFA perforated plate tightly through the pressure plate 13, and the ejector pin assembly 11 pushes upward to push the PFA tubes to the height required for fusion welding.

[0051] Step 2: Adjust the position of the hanger 15, start the hot air gun 17, the hot air rotates under the action of the spiral guide protrusion 28, and then heats the heating part through the hot air outlet. Start the first cylinder 14 to adjust the opening and closing size of the gap between the heat source core sleeve 21 and the lower part of the heat source outer sleeve 20 to ensure sufficient hot air density, and locally heat the PFA tubes and the PFA perforated plate to the fusion welding temperature. When the molten state starts to appear, start the second motor 8 to drive the upper die assembly 19 to move downward, apply a vertical pressure to the melted part, and rotate in the tangential direction at the same time to achieve rotary pressure welding. Then, cool the pressure plate 13 and the lower die plate 12 with water to cool the fusion welding part to the set temperature, and complete the fusion welding of one PFA tube and the PFA perforated plate.

[0052] Step 3: After repeating Step 2 to complete the fusion welding of all PFA tubes and PFA perforated plates, start the first motor 4 to separate the pressure plate 13 from the PFA perforated plate, start the second cylinder 9, and push the tube sheet out of the lower die plate 12 through the ejector pin assembly 11 to complete the fusion welding of the tube sheet.

[0053] The specific embodiments of the present invention disclosed above are only used to help illustrate the present invention. The specific embodiments do not describe all the details in detail, nor do they limit the invention to the specific embodiments described. According to the content of this specification, many modifications and changes can be made. These embodiments are selected and specifically described in this specification to better explain the principle and practical application of the present invention, so that those skilled in the art can understand and utilize the present invention well.

Claims

1. A fusion welding machine for soluble polytetrafluoroethylene tube sheets, characterized in that: It comprises an operating table (1), a sliding bracket (3), a fixed bracket (5), a top column assembly (11), a lower die plate (12), a pressing plate (13), a hanger (15), a hot air gun (17), an upper die assembly (19), a heat source jacket (20) and a heat source core jacket (21); the operating table (1) is provided with a lower guide rail (2); the sliding bracket (3) is slidably connected to the lower guide rail (2); an upper slide rail (16) is provided below the crossbeam of the sliding bracket (3); the fixed bracket (5) is provided with a plurality of upper and lower guide rails (17); and the upper and lower guide rails (17) are provided below the crossbeam of the sliding bracket (3). ) is slidably connected to the upper slide rail (16), a first motor (4) is arranged on the fixed frame (5), an output end of the first motor (4) is connected to a first lead screw (6), the first lead screw (6) is connected to a hanger (15), a second motor (8) is arranged on the hanger (15), the second motor (8) is connected to a second lead screw (18), the second lead screw (18) is threadedly connected to the hanger (15), the lower end of the second lead screw (18) is connected to an upper mold assembly (19), the heat The air gun (17) and the heat source jacket (20) are both connected to the hanger (15); an air inlet is provided on the heat source jacket (20); an air outlet of the hot air gun (17) is connected to the air inlet of the heat source jacket (20); the heat source core jacket (21) is arranged between the upper mold assembly (19) and the heat source jacket (20); the heat source core jacket (21) is connected to a pressure rod (22); the pressure rod (22) is connected to the first cylinder (14); the heat source jacket (20) and the heat source core jacket (21) have lower portions. They are all conical structures, the gaps at the bottom of the heat source jacket (20) and the heat source core jacket (21) are hot air outlets, the pressing plate (13) is arranged at the lower end of the hanger (15), the lower die plate (12) is arranged on the operating table (1), a plurality of die holes (23) are opened on the lower die plate (12), a plurality of top columns are arranged on the top column assembly (11), the positions of the plurality of top columns and the plurality of die holes (23) correspond one to one, and the bottom of the top column assembly (11) is connected to the second cylinder (9).

2. A fusion welding machine for soluble polytetrafluoroethylene tube sheets according to claim 1, characterized in that: The pressing plate (13) and the lower die plate (12) are both provided with cooling channels (24), and cooling water flows into the cooling channels (24).

3. A fusion welding machine for soluble polytetrafluoroethylene tube sheets according to claim 1, characterized in that: The pressing plate (13) comprises a pressing plate (25) and a pressing column (26); the pressing plate (25) is connected to the hanger (15); there are a plurality of pressing columns (26), and the plurality of pressing columns (26) are arranged below the pressing plate (25).

4. A fusion welding machine for soluble polytetrafluoroethylene tube sheets according to claim 1, characterized in that: The outer side of the heat source core sleeve (21) is provided with a spiral flow guide protrusion (28).

5. A fusion welding machine for soluble polytetrafluoroethylene tube sheets according to claim 1, characterized in that: The bottom end of the upper mold assembly (19) is a circular arc cone surface (27) structure.

6. A fusion welding machine for soluble polytetrafluoroethylene tube sheets according to claim 1, characterized in that: The hanger (15) is slidably connected to the fixing frame (5).

7. A fusion welding machine for soluble polytetrafluoroethylene tube sheets according to claim 1, characterized in that: The second motor (8) is connected to the second lead screw (18) via a transmission mechanism (7).

8. A fusion welding machine for soluble polytetrafluoroethylene tube sheets according to claim 1, characterized in that: There are two pressure rods (22), and the two pressure rods (22) are respectively connected to the heat source core sleeve (21) and the first cylinder (14).

9. A fusion welding machine for soluble polytetrafluoroethylene tube sheets according to claim 1, characterized in that: The lower part of the push column assembly (11) is connected to the push rod (10), and the push rod (10) is connected to the second cylinder (9).

10. A method for using the fusion welding machine for soluble polytetrafluoroethylene tube sheet as claimed in claim 1, characterized in that: It includes the following steps: Step 1: Start the second cylinder (9), push the push column assembly (11) upward, so that the push column enters the die hole (23) of the lower die plate (12), puts PFA tubes in all the die holes (23), places the PFA porous plate on the lower die plate (12) according to the position, presses the PFA porous plate by the pressing plate (13), pushes the push column assembly (11) upward, and pushes the PFA tube upward to the height required for welding; Step 2: Adjust the position of the hanger (15), start the hot air gun (17), and heat the heating part through the hot air outlet, and locally heat the PFA tube and the PFA porous plate to the melting temperature. When the melting state begins to appear, start the second motor (8) to drive the upper mold assembly (19) to move downward, apply vertical pressure to the melted part, and rotate in the tangential direction at the same time to achieve spin welding. When the melting part cools to the set temperature, the melting of a PFA tube and a PFA porous plate is completed; Step 3: After repeating step 2 to complete the fusion welding of all PFA tubes and PFA porous plates, start the first motor (4) to separate the pressing plate (13) from the PFA porous plate, start the second cylinder (9), and push the tube plate as a whole out of the lower mold plate (12) through the top column assembly (11), thereby completing the fusion welding of the tube plate.

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