Tube sheet simultaneous forming apparatus and method

Abstract

The application discloses a tube plate simultaneous forming device and method, which comprises a magnetic collector, a tube fixing mechanism, a plate fixing mechanism, a die assembly and a power supply mechanism; a containing hole penetrating through the magnetic collector is formed in the magnetic collector, a tube to be necked is inserted into the containing hole, and the outer wall of the magnetic collector comprises a plurality of side surfaces, wherein a magnetic conducting gap is formed in one of the side surfaces and communicates with the containing hole. The application has the advantages that electricity is directly supplied to the plate to be processed, the use of a coil is avoided, the problem of low mechanical strength and easy failure of the coil in the electromagnetic forming process is solved, the deformation resistance of a high-strength difficult-to-deform workpiece is reduced by using a self-resistance heating method, and for the processing of plates and tubes of different sizes, the coil does not need to be designed, the general structure of the magnetic collector does not need to be redesigned, and only the size of the magnetic collector needs to be changed to adapt to the deformation area of the tube plate, so that the cost is greatly reduced.

Description

Technical Field

[0001] This invention relates to the field of material forming technology, and in particular to a device and method for simultaneous tube sheet forming. Background Technology

[0002] Electromagnetic pulse forming (EPF) is a high-speed machining method for metal workpieces using pulsed magnetic field forces, and it is one of the key technologies for future manufacturing. EPF controls the spatiotemporal distribution of pulsed electromagnetic forces to cause high-speed deformation of metal materials, thereby evolving the workpiece's morphology and achieving plastic deformation processing. During EPF, the strain rate of the workpiece can reach speeds exceeding 300 m / s, thus improving the material's forming limit. Research shows that materials undergo high-speed deformation under the action of pulsed magnetic field forces, ultimately achieving forming performance superior to that obtained under traditional stamping processes.

[0003] Currently, electromagnetic forming is mainly used for processing sheet metal and tubing. Sheet metal processing primarily utilizes the axial force of the coil for forming, while tubing processing mainly utilizes the radial force of the coil. In traditional tube-sheet forming research, flat helical coils are used for sheet metal processing, and solenoid coils are used for tubing processing, with only one type of part formed per cycle. Furthermore, in traditional tube and sheet metal forming, solenoid coils and flat helical coils cannot be used interchangeably. Therefore, different coils and their respective tooling structures are required for tube and sheet metal forming, leading to increased costs. In addition, the mechanical strength of the coils is not high, and they are prone to failure after a period of use.

[0004] Chinese patent CN114769406A, entitled "Method and Forming Apparatus for Simultaneous Forming of Multiple Workpieces Using a Multi-Protruding Ring Magnetizer," provides an electromagnetic forming method for simultaneous processing of tube sheets. This method involves fabricating a multi-protruding ring magnetizer with a coil cavity, in which a drive coil is placed. Workpieces to be formed are positioned and fixed on the upper, lower, inner, and outer sides of the magnetizer, enabling simultaneous processing of the tube sheet and improving processing efficiency. However, the device and tooling designed for this method are complex, the magnetizer has a complex shape, and the coil needs to be embedded within it. Furthermore, as the tube sheet forming dimensions change, the magnetizer needs to be redesigned and remanufactured, resulting in high costs. Summary of the Invention

[0005] In view of this, it is necessary to provide a tube sheet forming apparatus and method that can process multiple sheets and a tube simultaneously without using coils, thereby reducing experimental tooling, improving production efficiency, and reducing the repetitive design and processing of coils, so as to reduce processing costs and improve economic benefits.

[0006] To achieve the above objectives, the present invention provides a tube sheet forming apparatus, comprising a magnet collector, a tube fixing mechanism, a sheet fixing mechanism, a mold assembly, and a power supply mechanism.

[0007] The magnet collector has a receiving hole that penetrates the magnet collector and extends along the length of the magnet collector. A tube to be necked is inserted into the receiving hole. The outer wall of the magnet collector includes several sides, one of which has a magnetic guide slit that communicates with the receiving hole.

[0008] The pipe fitting fixing mechanism includes two pipe fitting pressing blocks, which are respectively used to press the two ends of the pipe fitting;

[0009] The sheet metal fixing mechanism includes several pairs of sheet metal pressing blocks that are close to each side of the magnet collector. Each pair of sheet metal pressing blocks is close to but does not contact the side corresponding to the magnet collector. Each pair of sheet metal pressing blocks is used to fix a sheet metal to be formed.

[0010] The mold assembly includes several pairs of sheet metal molds that correspond one-to-one with the sheet metal pressing blocks. Each pair of sheet metal molds is used in conjunction with the sheet metal pressing blocks, and each pair of sheet metal molds is pressed onto the two ends of the corresponding sheet metal.

[0011] The power supply mechanism includes a pulse power supply and a discharge switch. The pulse power supply is electrically connected to each of the plates via the discharge switch and is used to pass a current parallel to the length direction of the plate onto each of the plates, so that an induced current is formed around the receiving hole on the outer surface of the magnet collector.

[0012] In some embodiments, the magnet collector includes two semi-rings and a connecting member, the two semi-rings being detachably connected and fastened together via the connecting member, and the receiving hole being located between the two semi-rings.

[0013] In some embodiments, if multiple plates and a pipe are to be processed simultaneously, the outer wall of the magnet collector is polygonal, and the number of the magnet collector's sides is multiple.

[0014] In some embodiments, the cross-section of the receiving hole is circular.

[0015] The present invention also provides a method for simultaneous tube sheet forming, applicable to the aforementioned tube sheet simultaneous forming apparatus, characterized by comprising the following steps:

[0016] S1. Fix the magnet collector on a workbench;

[0017] S2. Fix several sheets to be formed to the outer side wall of the magnet using sheet pressing blocks, and install each sheet mold.

[0018] S3. Place the tube to be formed into the receiving hole of the magnet collector, and fix the two ends of the tube with two tube pressing blocks;

[0019] S4. Connect each sheet to the pulse power supply via a discharge switch;

[0020] S5. Close the discharge switch and pass current through the pulse power supply to at least one of the plates to form an induced current around the receiving hole on the outer surface of the magnet collector, thereby generating induced eddy current in the tube to be formed, and then the electromagnetic force generated by the induced eddy current drives the tube and the plate to deform.

[0021] S6. After the discharge is complete, release the pressure block and the sheet metal mold, and then remove the sheet metal and pipe fittings to complete the processing.

[0022] In some embodiments, in step S5, if multiple plates are energized, the current direction is parallel to the length direction of the plates and the multiple plates form a clockwise or counterclockwise ring current, so that the outer surface of the magnet collector forms an induced current surrounding the receiving hole, thereby generating induced eddy current in the tube to be formed, and then the induced eddy current generates electromagnetic force to drive the tube and the plates to deform.

[0023] In some embodiments, the pulse power supply is connected in parallel or in series with each of the sheet metals.

[0024] In some embodiments, the fitting is made of a high-conductivity material.

[0025] In some embodiments, the sheet is made of a low-conductivity material.

[0026] Compared with existing technologies, the beneficial effects of the technical solution proposed in this invention are as follows: Compared with traditional electromagnetic forming, simultaneous processing of tube sheets and plates saves costs and improves the processing efficiency and energy utilization efficiency of electromagnetic forming. Furthermore, in this invention, electricity is directly applied to the sheet material to be processed, avoiding the use of coils and solving the problems of low mechanical strength and easy failure of coils in electromagnetic forming. Directly applying electricity to the sheet material would raise the temperature of the sheet material, thereby reducing its deformation resistance. Simultaneously, multi-sheet single-tube processing effectively utilizes the electromagnetic force on the coils, greatly improving the energy utilization efficiency of electromagnetic forming. In addition, for processing sheet materials and tubes of different sizes, there is no need to design coils, and the overall structure of the magnet collector does not need to be redesigned; only the size of the magnet collector needs to be changed to adapt to the deformation area of ​​the tube sheet, significantly reducing costs. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of an embodiment of the tube sheet forming device provided by the present invention;

[0028] Figure 2 yes Figure 1 A three-dimensional structural diagram of the magnet collector in the image;

[0029] Figure 3 yes Figure 2 A three-dimensional structural diagram of the magnet collector after the installation of pipe fittings and sheet metal;

[0030] Figure 4 yes Figure 3 A schematic diagram showing the direction of current flow after the cross-section of the magnetically conductive slot is cut open;

[0031] Figure 5 yes Figure 3 Top view and schematic diagram of current flow direction;

[0032] Figure 6 This is a schematic diagram of the deformation of the sheet metal after processing;

[0033] Figure 7 This is a schematic diagram of the deformation of the pipe fitting after processing;

[0034] Figure 8 It is a three-dimensional structural diagram of the plate and pipe after processing;

[0035] Figure 9 This is a schematic diagram illustrating the change in the length of the internal aperture of the magnet collector in Embodiment 2;

[0036] Figure 10 This is a schematic diagram of how the shape of the outer wall of the magnet collector is changed in Example 3 to achieve the simultaneous processing of multiple plates and a pipe.

[0037] In the figure: 1-Magnetic collector, 1A-First semi-ring, 1B-Second semi-ring, 11-Accommodation hole, 12-Magnetic guide seam, 13-Connecting component, 14-Side, 2-Sheet metal fixing mechanism, 21-Sheet metal pressing block, 3-Mold assembly, 31-Sheet metal mold, 4-Power supply mechanism, 5-Pipe fitting, 6-Sheet metal, 61-First sheet metal, 62-Second sheet metal, 63-Third sheet metal, 64-Fourth sheet metal. Detailed Implementation

[0038] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which form part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0039] Please refer to Figures 1-10 The present invention provides a tube sheet forming device, including a magnet collector 1, a tube fixing mechanism (not shown), a sheet fixing mechanism 2, a mold assembly 3, and a power supply mechanism 4.

[0040] The magnet collector 1 is made of copper, a material with high conductivity. A receiving hole 11 is formed inside the magnet collector 1, which extends through the magnet collector 1 and along the length of the magnet collector 1. A tube 5 to be necked is inserted into the receiving hole 11. The outer wall of the magnet collector 1 includes several side surfaces 14, one of which has a magnetic guide slit 12 that communicates with the receiving hole 11. The induced current generated on the outer surface of the magnet collector 1 flows into the inner surface of the magnet collector 1 (i.e., the inner side wall of the receiving hole 11) through the magnetic guide slit 12.

[0041] The pipe fitting fixing mechanism includes two pipe fitting pressing blocks, which are respectively used to press the two ends of the pipe fitting 5 to fix the pipe fitting 5 to the magnet collector 1.

[0042] The sheet metal fixing mechanism 2 includes several pairs of sheet metal pressing blocks 21 that are close to each side 14 of the magnet collector 1. Each pair of sheet metal pressing blocks 21 is close to but does not contact the side 14 corresponding to the magnet collector 1. Each pair of sheet metal pressing blocks 21 is used to fix a sheet metal 6 to be formed, so that a sheet metal 6 is fixed on each side of the magnet collector 1.

[0043] The mold assembly 3 includes several pairs of sheet metal molds 31 that correspond one-to-one with the sheet metal pressing blocks 21. Each pair of sheet metal molds 31 is used in conjunction with the sheet metal pressing blocks 21, and each pair of sheet metal molds 31 is pressed onto both ends of the corresponding sheet metal 6.

[0044] The power supply mechanism 4 includes a pulse power supply and a discharge switch. The pulse power supply is electrically connected to each of the plates 6 via the discharge switch and is used to supply current in different directions to each of the plates 6. The number of plates 6 can be one or more. If only one plate 6 is energized, the current direction should be parallel to the length direction of the plate 6. If multiple plates 6 are energized, the current direction should be parallel to the length direction of the plate 6 and make the multiple plates 6 form a clockwise or counterclockwise circular current, so that an induced current is formed around the receiving hole 11 on the outer surface of the magnet collector 1.

[0045] In use, the magnet collector 1 is fixed on a workbench; several sheets 6 to be formed are fixed to the corresponding side 14 on the outer wall of the magnet collector 1 by sheet pressing blocks 21, and each sheet mold 31 is installed; the tube 5 to be formed is placed in the receiving hole 11 of the magnet collector 1, and the two ends of the tube 5 are fixed by two tube pressing blocks; each sheet 6 is connected to a pulse power supply via a discharge switch; the discharge switch is closed, and current is passed through the pulse power supply to at least one of the sheets 6, so that an induced current is formed around the receiving hole 11 on the outer surface of the magnet collector 1, thereby generating induced eddy currents in the tube 5 and the sheet 6 to be formed, and then the induced eddy currents generate electromagnetic force to drive the tube 5 and the sheet 6 to deform.

[0046] Compared to traditional electromagnetic forming, simultaneous processing of tubes and sheets saves costs and improves the processing efficiency and energy utilization efficiency of electromagnetic forming. Furthermore, in this invention, electricity is directly applied to the sheet material 6 to be processed, eliminating the need for coils and solving the problems of low mechanical strength and easy failure of coils in electromagnetic forming. Directly applying electricity to the sheet material would raise its temperature, thus reducing its deformation resistance. In addition, for processing sheet materials 6 and tubes 5 of different sizes, there is no need to design coils, and the overall structure of the magnet collector does not need to be redesigned; only the size of the magnet collector needs to be changed to adapt to the deformation area of ​​the tube and sheet, significantly reducing costs.

[0047] For easier loading and unloading of pipe fitting 5 to be processed, please refer to... Figures 1-10 In a preferred embodiment, the magnet collector 1 includes two semi-rings (a first semi-ring 1A and a second semi-ring 1B in this embodiment) and a connecting component 13. The two semi-rings are detachably connected and fastened together via the connecting component 13. The receiving hole 11 is located between the two semi-rings. In a specific embodiment, the connecting component 13 includes a male buckle and a female buckle, wherein the male buckle is fixed to the first semi-ring 1A and the female buckle is fixed to the second semi-ring 1B. The connection between the first semi-ring 1A and the second semi-ring 1B is achieved by fastening the male buckle and the female buckle.

[0048] For ease of use, please refer to Figures 1-10 In a preferred embodiment, if multiple sheets 6 and one pipe fitting 5 are to be processed simultaneously, the outer wall of the magnet collector is a polygonal prism, and the number of the magnet collector's sides is multiple. For example, in one embodiment, the outer wall of the magnet collector 1 is a quadrangular prism, and the number of the sides 14 is four. In another embodiment, the outer wall of the magnet collector 1 is a hexagonal prism, and the number of the sides is six. It should be understood that in this invention, the shape of the outer wall of the magnet collector 1 (i.e., the number of sides) can be flexibly designed, and the magnet collector can also be designed as a polyhedral structure depending on the number of sheets to be formed.

[0049] For easier insertion of the round tube, please refer to... Figures 1-10 In a preferred embodiment, the cross-section of the receiving hole 11 is circular.

[0050] The present invention also provides a method for simultaneous tube sheet forming, applicable to the aforementioned tube sheet simultaneous forming apparatus, comprising the following steps:

[0051] S1. Fix the magnet collector 1 on a workbench;

[0052] S2. Fix several sheet metal pieces 6 to be formed to the outer side 14 of the magnet collector 1 by sheet metal pressing blocks 21, and install each sheet metal mold 31.

[0053] S3. Place the tube 5 to be formed into the receiving hole 11 of the magnet collector 1, and fix the two ends of the tube 5 with two tube pressing blocks.

[0054] S4. Connect each sheet 6 to the pulse power supply via a discharge switch;

[0055] S5. Close the discharge switch and pass current through the pulse power supply to at least one of the sheet metal 6 so that an induced current is formed around the receiving hole 11 on the outer surface of the magnet collector 1, thereby generating induced eddy current in the pipe 5 to be formed and the sheet metal 6 to be formed, causing the pipe 5 and the sheet metal 6 to deform.

[0056] S6. After the discharge is completed, release the pressure block and the plate mold 31, and then remove the plate 6 and the pipe 5 respectively to complete the processing.

[0057] To improve the forming effect, please refer to Figure 1 In a preferred embodiment, in step S5, currents in different directions are passed through each of the sheet metal 6 (the number of energized sheet metal 6 can be one or more; if only one sheet metal 6 is energized, the current direction should be parallel to the length direction of the sheet metal 6; if multiple sheet metal 6 are energized, the current direction should be parallel to the length direction of the sheet metal 6 and form a clockwise or counterclockwise circular current among the multiple sheet metal 6), so that an induced current is formed around the receiving hole 11 on the outer surface of the magnet collector 1, thereby generating induced eddy currents in the tube 5 to be formed and the sheet metal 6 to be formed, causing deformation of the tube 5 and the sheet metal 6.

[0058] To reduce costs, please refer to Figure 1In a preferred embodiment, the pulse power supply is connected in parallel or series with each of the sheet metal 6, so that each sheet metal 6 can be energized simultaneously by one pulse power supply. It should be understood that in this invention, multiple pulse power supplies can also be used to energize each sheet metal 6 at the same time. This invention does not limit this. Specifically, if it is parallel loading, multiple power supplies are used to power the sheet metal respectively. If it is series loading, conductive blocks are needed to connect the end faces of the sheet metal 6 to form a loop and then use one power supply.

[0059] To achieve the electromagnetic forming function, please refer to... Figures 1-10 In a preferred embodiment, the pipe 5 is an aluminum alloy pipe, and the sheet 6 is a high-strength, difficult-to-form thin sheet 6. Leveraging the high strain rate characteristic of electromagnetic forming and the self-resistance heating characteristic that reduces the deformation resistance of high-strength, difficult-to-deform workpieces, this electromagnetic forming method can significantly improve the forming limits of the sheet 6 and pipe 5 without producing machining marks, thus offering certain processing advantages compared to traditional processing methods.

[0060] To better understand the present invention, the implementation process of the present invention will be described in detail below through the following specific embodiments.

[0061] Example 1

[0062] Please refer to Figures 1-8 Example 1 provides a square magnet collector 1 with a circular hole. Four independent plates 6 are arranged around the square magnet collector 1, and a tube 5 to be necked is placed inside the receiving hole 11 of the magnet collector 1. A narrow magnetic guide slit 12 is provided in the center of the magnet collector 1 to facilitate the transmission of induced current. During processing, currents in different directions are applied to the four plates 6. The current-carrying plates 6 will induce current with the magnet collector 1, thereby generating an induced current on the outer surface of the magnet collector 1. The induced current on the outer surface of the magnet collector 1 flows into the inner surface of the magnet collector 1 through the magnetic guide slit 12, and the current on the inner surface of the magnet collector 1 induces a current in the tube 5 to be necked. A magnetic field is generated by the induced current, and the interaction of the magnetic fields generates an electromagnetic force, thus achieving the purpose of simultaneously processing four plates 6 and one tube 5.

[0063] Please refer to Figure 2 and Figure 3This invention provides a magnet collector 1. The magnet collector 1 includes two semi-ring bodies (in this embodiment, a first semi-ring body 1A and a second semi-ring body 1B) and a connecting component 13. The first semi-ring body 1A and the second semi-ring body 1B are detachably connected and fastened together via the connecting component 13. The receiving hole 11 is located between the two semi-ring bodies. The presence of the connecting component 13 allows the magnet collector 1 to have an open structure, facilitating the installation and removal of the pipe fitting 5. The outer wall of the square magnet collector 1 with a circular hole is square, allowing four plates 6 to be placed (in this embodiment, a first plate 61, a second plate 62, a third plate 63, and a fourth plate 64). The receiving hole 11 is circular. During processing, by applying currents in different directions to the first plate 61, the second plate 62, the third plate 63, and the fourth plate 64, the currents on each plate 6 generate a ring current along the outer wall of the magnet collector 1. The ring current on the outer surface of the magnet collector 1 flows into its inner wall through the magnetic guide slit 12.

[0064] Please refer to Figure 3 When processing sheet metal 6 and pipe fitting 5, sheet metal pressing blocks 21 and sheet metal molds 31 are set at both ends of sheet metal 6, so that sheet metal 6 can achieve the ideal deformation shape.

[0065] Please refer to Figure 4 , Figure 4 This is a schematic diagram of the device after being cut open from the cross-section of the magnetically conductive seam 12. The current distribution on the left plate 6 (i.e., the first plate 61) is perpendicular to the cross-section and points inwards, while the current on the right plate 6 (i.e., the third plate 63) is perpendicular to the cross-section and points outwards. The induced current formed on the left side of the pipe 5 is perpendicular to the cross-section and points outwards, while the induced current formed on the right side of the pipe 5 is perpendicular to the cross-section and points inwards.

[0066] Please refer to Figure 5 , Figure 5 This is the overall current principle diagram. A current flows upward along the Y-axis on the third plate 63, a current flows to the right along the X-axis on the fourth plate 64, a current flows downward along the Y-axis on the first plate 61, and a current flows to the left along the X-axis on the second plate 62. The four plates generate a clockwise circular current. The plates 6 and the magnet collector 1 induce each other, generating a counter-clockwise current on the outer surface of the magnet collector 1. This induced current on the outer surface of the magnet collector 1 flows into the inner surface through the magnetic guide slit 12, thus generating a clockwise induced current on the inner surface of the magnet collector 1. The inner surface of the magnet collector 1 interacts with the tube 5 to be necked, generating a counter-clockwise induced current on the tube 5.

[0067] Please refer to Figure 6 , Figure 6This is a deformation diagram of the sheet metal after processing. After electromagnetic forming, due to the action of electromagnetic force, an electromagnetic force perpendicular to the sheet metal surface is generated at the center of sheet metal 6, causing sheet metal 6 to deform under the drag of the electromagnetic force. However, due to the presence of sheet metal pressing block 21 and sheet metal mold 31, the two ends of sheet metal 6 will not displace. Therefore, under the combined action of pressing force and electromagnetic force, sheet metal 6 will undergo deformation from the center outward.

[0068] Please refer to Figure 7 , Figure 7 This is a deformation diagram of pipe fitting 5 after processing. Under the action of magnetizer 1, pipe fitting 5 generates a circular current. Due to the presence of this circular current, pipe fitting 5 is subjected to a uniform electromagnetic force. Since both ends of pipe fitting 5 are fixed, the pipe fitting 5 will experience a necking effect in the middle under the action of the electromagnetic force.

[0069] Please refer to Figure 8 , Figure 8 This refers to the forming effect achieved by the pipe fitting 5 and the sheet 6 after processing.

[0070] Example 2

[0071] Please refer to Figure 9 In Example 2, the length of the receiving hole 11 inside the magnet collector 1 was changed, thereby making the magnetic field more concentrated and the necking of the tube 5 more uniform.

[0072] Specifically, since the receiving hole 11 of the magnet collector 1 in embodiment 2 is shorter, the force on the tube 5 is mainly concentrated in the middle part, so the force on the tube 5 is more uniform and the necking effect is better.

[0073] Example 3

[0074] Please refer to Figure 10 Six plates 6 are fixed around the hexagonal magnet collector 1 with round holes. The tube 5 to be necked is placed in the receiving hole 11 of the magnet collector 1 and fixed at both ends. Currents in different directions are applied to the six plates 6. The current in the plates will induce an induced current in the magnet collector, which will then react with the tube. This creates a strong magnetic field in space, and the magnetic force in space will cause the plates 6 and the tube 5 to be processed simultaneously. After processing, the clamping blocks on the plates 6 are loosened first, the plates 6 are removed, and then the connecting part 13 on the magnet collector 1 is opened to remove the processed tube 5.

[0075] Example 4

[0076] Please refer to Figure 2 , Figure 4 Embodiment 4 of the present invention provides a method for simultaneous processing of tube sheets, the specific steps of which are as follows:

[0077] (1) Fix the first plate 61, the second plate 62, the third plate 63 and the fourth plate 64 around the square magnet 1 with round holes respectively;

[0078] (2) Place the tube 5 to be necked into the receiving hole 11 of the magnet collector 1 and fix both ends;

[0079] (3) After fixing each plate 6, four pulse power supplies or one pulse power supply (connecting the four plates into a circuit through the conductive block) can be used to supply current in different directions to the plates;

[0080] (4) A current in the Y-axis direction is passed on the third plate 63, a current in the X-axis direction is passed on the fourth plate 64, a current in the Y-axis direction is passed on the first plate 61, and a current in the X-axis direction is passed on the second plate 62.

[0081] (5) During the processing, the currents in different directions on the four plates 6 will generate a ring current around the surface of the magnet collector 1. Due to the presence of the ring current, the current on the magnet collector 1 will induce a mutual current with the tube to be necked 5, thereby generating a ring current around the surface of the tube to be necked 5. After the circuit is turned on, the plates 6 and the magnet collector 1 will generate a strong magnetic field, and the magnet collector 1 and the tube to be necked 5 will generate a strong magnetic field. Thus, the simultaneous processing of the four plates 6 and one tube 5 is completed.

[0082] (6) After processing, loosen the plate pressing block 21 and remove the plate 6. Loosen the connecting part 13 to open the magnet 1 and remove the necked tube 5.

[0083] Example 5

[0084] Embodiment 5 of the present invention provides another method for simultaneous processing of tube sheets, the specific steps of which are as follows:

[0085] (1) Fix the first plate 61, the second plate 62, the third plate 63 and the fourth plate 64 around the square magnet 1 with round holes respectively;

[0086] (2) Place the tube 5 to be necked into the receiving hole 11 of the magnet collector 1 and fix both ends;

[0087] (3) Unlike Example 4, which energizes all four plates 6, in Example 5, only the first plate 61 is energized during processing;

[0088] The subsequent steps are the same as in Example 4.

[0089] In this embodiment, by passing a downward Y-axis current through the first sheet metal 61, the current on the first sheet metal 61 will induce a ring current on the outer surface of the magnet collector 1. The current on the magnet collector 1 will not only induce an electromagnetic force with the tube 5 to be necked, but also induce an electromagnetic force with the other three unenergized sheets metal 6. This achieves the purpose of processing four sheets metal 6 and one tube 5 simultaneously.

[0090] In summary, this invention discloses a processing apparatus and method for simultaneous processing of tube sheets, and constructs a square magnet collector with a circular hole. During processing, by applying currents in different directions to the sheet metal, the current-carrying sheet metal will induce a current with the magnet collector, thereby generating an induced current on the magnet collector. The induced current on the magnet collector will then induce a current with the necked tube. The induced current generates electromagnetic force, thus achieving the purpose of simultaneously processing the tube sheet. According to the characteristics of this method, directly energizing the sheet metal to be processed avoids the use of coils, solving the problem of low mechanical strength and easy failure of coils in electromagnetic forming. In addition, multiple sheets and one tube can be processed simultaneously with a single energization, improving the production efficiency of parts processing. Furthermore, the magnet collector has a simple structure and low processing cost.

[0091] Since no coil is present during processing, and current is applied directly to the sheet metal to be processed, the processing of multiple sheets 6 and one tube 5 effectively avoids the use of coils, solving the problem of coil failure due to excessive force. Moreover, the processing of multiple sheets and a single tube not only solves the problem of easy coil failure and reduces the manufacturing cost of coils, but also effectively utilizes the electromagnetic reaction force on the coil, greatly improving the energy utilization efficiency of electromagnetic forming.

[0092] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for simultaneous forming of tube sheets, characterized in that, The following tube sheet forming device is used for simultaneous forming: The tube sheet forming device includes a magnet collector, a tube fixing mechanism, a sheet fixing mechanism, a mold assembly, and a power supply mechanism. The magnet collector has a receiving hole that penetrates the magnet collector and extends along the length of the magnet collector. A tube to be necked is inserted into the receiving hole. The magnet collector includes several outer walls, one of which has a magnetic slit that communicates with the receiving hole. The pipe fitting fixing mechanism includes two pipe fitting pressing blocks, which are respectively used to press the two ends of the pipe fitting; The sheet metal fixing mechanism includes several pairs of sheet metal pressing blocks that are close to each side of the magnet collector. Each pair of sheet metal pressing blocks is close to but does not contact the corresponding side of the magnet collector. Each pair of sheet metal pressing blocks is used to fix a sheet metal to be formed. The mold assembly includes several pairs of sheet metal molds that correspond one-to-one with the sheet metal pressing blocks. Each pair of sheet metal molds is used in conjunction with the sheet metal pressing blocks, and each pair of sheet metal molds is pressed onto the two ends of the corresponding sheet metal. The power supply mechanism includes a pulse power supply and a discharge switch. The pulse power supply is electrically connected to each of the plates via the discharge switch and is used to pass a current parallel to the length direction of the plate onto each of the plates, so that an induced current is formed around the receiving hole on the outer surface of the magnet collector. If multiple plates and one pipe are to be processed simultaneously, the outer wall of the magnet collector is a polygonal prism, and the number of the magnet collector's sides is multiple. The method for simultaneous tube sheet forming includes the following steps: S1. Fix the magnet collector on a workbench; S2. Fix several sheets to be formed to the outer side wall of the magnet using sheet pressing blocks, and install each sheet mold. S3. Place the tube to be formed into the receiving hole of the magnet collector, and fix the two ends of the tube with two tube pressing blocks; S4. Connect each sheet to the pulse power supply via a discharge switch; S5. Close the discharge switch and apply a current parallel to the length of the sheet material to at least one of the sheet materials via a pulse power supply. This causes an induced current to form around the receiving hole on the outer surface of the magnet collector, thereby generating induced eddy currents in the tube to be formed. The induced eddy currents then generate electromagnetic force to drive the tube and sheet material to deform. If multiple sheet materials are energized, the current direction is parallel to the length of the sheet materials and causes multiple sheet materials to form a clockwise or counterclockwise circular current. This causes an induced current to form around the receiving hole on the outer surface of the magnet collector, thereby generating induced eddy currents in the tube to be formed. The induced eddy currents then generate electromagnetic force to drive the tube and sheet material to deform simultaneously. S6. After the discharge is complete, release the pressure block and the sheet metal mold, and then remove the sheet metal and pipe fittings to complete the processing.

2. The method for simultaneous tube sheet forming according to claim 1, characterized in that, The magnet collector includes two semi-rings and a connecting component. The two semi-rings are detachably connected and fastened together via the connecting component, and the receiving hole is located between the two semi-rings.

3. The method for simultaneous tube sheet forming according to claim 1, characterized in that, The cross-section of the receiving hole is circular.

4. The method for simultaneous tube sheet forming according to claim 1, characterized in that, The pulse power supply is connected in parallel or in series with each of the sheet materials.

5. The method for simultaneous tube sheet forming according to claim 1, characterized in that, The pipe fitting is made of aluminum alloy.

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