Laser welding method for hydrogen production pole frame and pole plate

Abstract

The invention relates to a laser welding method for a hydrogen production pole frame and a pole plate. The method comprises: dividing a welding track into a plurality of sections according to a welding order along the entire inner contour of a second plate body or a third plate body of a pole plate to be welded, the welding order of the section of the welding track corresponding to the ear opening is the latter, the welding tracks of adjacent sections meet and overlap, and double-sided laser welding of connecting the two sides of a first plate body to the second plate body and the third plate body respectively is completed along the plurality of welding tracks according to the welding order. With an annular clamp, suitable laser welding parameters, strong gas protection and dust extraction, spatter and post-weld deformation of the pole plate can be significantly reduced, welding efficiency and weld quality can be improved, and qualified weld width, excess height, weld depth and weld with smooth and flat appearance and no pore defects can be obtained under relatively small heat input. The single-side warping of the pole plate after welding is ≤12 mm, and the single weld pressure value is much greater than 50 MPa, which is conducive to reducing the risk of subsequent film damage, simplifying pole frame processing, improving production efficiency and reducing production costs.

Description

Technical Field

[0001] The invention belongs to the field of hydrogen energy pole frame and pole plate welding, and in particular relates to a laser welding method for hydrogen production pole frame and pole plate. Background Art

[0002] With the vigorous development of my country's new energy industry and increasingly stringent requirements for environmental protection, the development of the hydrogen energy industry is imperative. As the hydrogen production reaction site of hydrogen energy batteries, the importance of hydrogen production pole frame is self-evident. The current development of hydrogen energy technology has put forward higher requirements for the welding of hydrogen production pole frame plates. Different from the existing metal bipolar plates directly welded by anode thin plates and cathode thin plates, the raw materials of hydrogen energy pole frame plate products are made of the following materials: Figure 1 The three plates shown are spliced ​​together, and several pole frames and plates are spliced ​​together to form a pole frame. Because a film needs to be covered on the pole frame and the pole plate to form a hydrogen production environment, high requirements are placed on the amount of spatter during welding, the flatness of the weld, and the amount of deformation after welding. The existing welding method has the following problems:

[0003] (1) When using arc welding, due to the large arc heat input and unstable droplet transition, the weld width is wide, the excess height is large, the spatter is large, and the weld surface is uneven. The large amount of spatter in the welding will increase the risk of damaging the film, and adding a grinding process will increase costs and reduce efficiency. Large excess height, poor flatness, and large deformation after welding will increase the difficulty of the post-welding pole frame leveling process, affect the plate stacking, and reduce production efficiency. The maximum arc welding speed can reach 500mm / min to 900mm / min, resulting in low welding efficiency.

[0004] (2) Compared with arc welding, laser welding has the advantages of fast welding speed, concentrated heat and less thermal deformation of materials. However, for welding pole frame and pole plate with a thickness of 1-4mm and steel plates with ears, there is a lack of appropriate welding sequence and the welding trajectory is formed in a whole circle, which will increase the heat input and welding deformation of the parent material and lead to poor air tightness of the weld. The deformation of the pole plate after welding: the single-sided warping is ≥23mm. Its welding parameters: welding power, welding speed, and defocus distance synergistically affect the welding effect. Poor welding parameters can easily lead to uneven surface affecting the flatness of the assembly, large spatter damaging the subsequent surface film, or poor penetration and failure to form an effective connection. Its pressure value fails to reach the required value of 50MPa.

[0005] (3) The lack of fixtures and jigs for laser welding makes it impossible to meet the requirements of the precision laser welding process and causes uncontrollable deformation. Weak gas protection leads to porosity defects or improper control leads to poor welds and decreased mechanical properties. The lack of a dust extraction system leads to large amounts of smoke and affects the cleanliness of the weld surface.

[0006] Therefore, the welding quality requirements cannot be met, which limits the application and development of hydrogen production pole frame and pole plate. Summary of the invention

[0007] The present invention aims to solve at least one of the above technical problems to a certain extent. The present invention provides a laser welding method for hydrogen production pole frame and pole plate, which reduces spatter and post-weld deformation of the pole plate, improves welding efficiency and weld quality, and facilitates the application of hydrogen production pole frame and pole plate.

[0008] The technical solution adopted by the present invention to solve its technical problem is:

[0009] A laser welding method for hydrogen production pole frame and pole plate, the method comprising:

[0010] The electrode plates to be welded include a first plate body, a second plate body and a third plate body, and the inner contours of the second plate body and the third plate body include ears; the welding track is divided into several sections according to the welding order along the inner contour of the entire circumference of the second plate body or the third plate body, and the welding order of the section of the welding track corresponding to the ears is the last, and the adjacent sections of the welding track are overlapped head to tail, which can reduce welding deformation and ensure the air tightness of the weld compared with the existing welding method of forming the whole circle in one go, and ensure that the weld of each section of the welding track can be well connected;

[0011] The laser welding equipment completes double-sided laser welding of the first plate body to the second plate body and the third plate body along several welding tracks in a welding sequence to obtain a pole plate, which can reduce the deformation after welding and reduce the difficulty of assembling the pole frame.

[0012] Furthermore, the materials of the first plate body, the second plate body and the third plate body include hot-formed steel and carbon steel, which affect the absorption rate of laser and have good welding performance and material strength.

[0013] Furthermore, the thickness of the first plate body is 3-4 mm, the thickness of the second plate body is 1-2 mm, and the thickness of the third plate body is 1-2 mm, which further meets the requirements of the hydrogen production pole frame and pole plate.

[0014] Furthermore, corresponding positioning holes are provided on the first plate body, the second plate body and the third plate body, and an annular clamp is provided on the workbench of the laser welding equipment. The annular clamp includes a base arranged on the workbench, a bottom plate capable of rotating around the center relative to the base, and a plurality of quick clamps and a pressure plate arranged at intervals around the top of the bottom plate. The bottom plate and the base are provided with a plurality of rotating pin holes corresponding to the positioning holes, and the pressure plate is provided with a recess corresponding to the shape of the ear mouth. The use of the annular clamp can effectively fix the electrode plate and reduce the post-welding deformation of the electrode plate.

[0015] Furthermore, during laser welding along the first section of the welding trajectory, the electrode plate to be welded is clamped on the bottom plate and the relative rotation between the bottom plate and the base is restricted by inserting pins into the positioning holes and rotating pin holes, and clamping with the quick clamp and the pressure plate. The concave opening of the pressure plate corresponds to the ear opening and is pressed on top of the second plate body or the third plate body. Several quick clamps can be pressed in a ring shape on top of the pressure plate, the second plate body or the third plate body, so as to realize the rapid positioning, installation and reliable clamping of the first plate body, the second plate body or the third plate body, thereby improving the laser welding accuracy and reducing the post-welding deformation of the electrode plate.

[0016] Furthermore, the pressing plate and the bottom plate are provided with a plurality of position pin holes for making way for the hydrogen-producing pole frame plates, and the pins are inserted into the position pin holes to realize the positioning of the pressing plate and the bottom plate, so as to facilitate the rapid disassembly and assembly of the pressing plate and improve the welding efficiency.

[0017] Furthermore, before or after laser welding, the base plate is rotated to move the electrode plate to be welded until the laser head of the laser welding equipment is located at the corresponding welding track, which can simplify the assembly steps and improve the welding efficiency of large-format electrode plates.

[0018] Furthermore, before laser welding along the first welding trajectory, the gap between the first plate and the second plate or between the first plate and the third plate is less than 0.2 mm, so as to avoid excessive gap affecting the penetration depth and weld width, causing weld penetration, fusion difficulties and weld defects.

[0019] Furthermore, the welding heat source of laser welding is a laser with a maximum output power of 6kw. High-energy laser pulses can be used to locally heat the material in a small area. With a small heat input, the required melting depth can be achieved, thereby reducing the post-welding thermal deformation of the plate and helping to reduce the difficulty of assembling the pole frame.

[0020] Furthermore, the laser welding parameters include: welding power of 3600W to 5400W, to avoid excessive welding power causing uneven plate surface and increased spatter, to avoid poor penetration caused by too small welding power; welding speed of 20 to 50mm / s, preferably 20 to 30mm / s, that is, it can reach 1800mm / min, which is significantly higher than arc welding speed, and the welding speed is controlled to cooperate with the welding power to ensure that the heat input meets the maximum penetration requirement, to avoid excessive welding speed causing too small penetration and inability to effectively connect, to avoid excessive welding speed causing excessive melting of the plate or even welding through; defocus of +25 to -25mm, to avoid too small defocus causing narrowing of the weld, increased excess height and spatter, to avoid too large defocus causing poor penetration of the weld and inability to form an effective connection, so as to reduce spatter during welding and improve welding efficiency and obtain a weld with a smooth surface by optimizing the laser welding parameters.

[0021] Furthermore, a shielding gas blowing device is coaxially provided on the laser head of the laser welding equipment. The parameters of the shielding gas blowing device during laser welding include: argon gas, gas flow rate: 15-25L / min, distance between the gas shielding nozzle and the welding surface: 8-10mm. By enhancing the shielding gas to exclude air from the local welding area, protect the working surface from oxidation, inhibit the generation of plasma cloud during laser welding, avoid porosity defects, and control the shielding gas parameters, the weld formation becomes smooth and the spatter amount is greatly reduced, thereby reducing the risk of film damage in subsequent processes.

[0022] Furthermore, a dust extraction mechanism is provided on the side axis of the laser head of the laser welding equipment. The dust extraction mechanism is used to remove welding fumes through negative pressure adsorption during laser welding, which can reduce spatter during welding and obtain a weld with a smooth surface, thereby simplifying the process of grinding spatter and improving production efficiency.

[0023] Furthermore, after the laser head of the laser welding equipment completes the laser welding of the second plate body and one side of the first plate body above the second plate body, the second plate body and the first plate body are flipped over, so that the laser head completes the laser welding of the third plate body and the other side of the first plate body above the third plate body, thereby realizing double-sided welding under improved process sequence, reducing the deformation after welding, and reducing the difficulty of assembling the pole frame.

[0024] Furthermore, the surface of the electrode plate weld is flat and smooth, which reduces the risk of film damage in subsequent processes of the electrode frame and electrode plate. The single weld pressure bearing value of the electrode plate is far greater than 50MPa and can reach 393MPa, which can meet the application requirements of the electrode frame and electrode plate.

[0025] Furthermore, the plate weld width is 2 to 4 mm, and the excess height is less than 0.25 mm, ensuring that the excess height coefficient = weld width / excess height meets the requirements, thereby avoiding stress concentration causing a decrease in the dynamic load bearing capacity of the weld.

[0026] Furthermore, the deformation of the electrode plate after welding: the single-side warping is ≤12mm, which reduces the difficulty of the electrode frame leveling process after welding, and also greatly reduces the difficulty of assembling the electrode frame with several electrode plates, thereby improving product production efficiency.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] (1) The present invention adopts a double-sided laser welding process under a segmented, head-to-tail overlapping, and ear-mouth welding sequence, and obtains a weld with qualified weld width, excess height, weld depth, smooth and flat appearance, and no porosity defects under a relatively small heat input. Compared with arc welding, the welding efficiency can be significantly improved and arc welding problems can be avoided. Compared with the existing welding method of forming the entire circle in one go, the welding deformation can be significantly reduced.

[0029] (2) The present invention adopts appropriate laser welding parameters, and through the optimization of welding power, welding speed and defocusing amount, spatter during welding is reduced, a clean and tidy weld surface is obtained, and an effective connection is formed, thereby avoiding large excess height and uneven surface that affect the flatness of the assembly when assembling the pole frame.

[0030] (3) The present invention adopts an annular clamp, which is easy to operate and can effectively fix the electrode plate, thereby improving the laser welding accuracy and reducing the post-welding deformation of the electrode plate.

[0031] (4) The present invention adopts strong gas protection and dust extraction to remove smoke, so that the weld formation becomes smooth and the amount of spatter is significantly reduced.

[0032] In summary, the present invention can significantly reduce spatter and post-weld deformation of the electrode plate, improve welding efficiency and weld quality, and the post-weld deformation of the electrode plate is reduced from a single-sided warping of 23 mm to a single-sided warping of ≤12 mm, the electrode plate weld width is 2 to 4 mm, the excess height is <0.25 mm, and the single weld pressure value is much greater than 50 MPa, which is beneficial to reducing the risk of subsequent film damage, simplifying electrode frame processing, improving production efficiency, and reducing production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0034] Figure 1 It is an assembly diagram of the electrode plates to be welded according to the present invention;

[0035] Figure 2 This is a top view of the electrode plate assembly of the present invention;

[0036] Figure 3 is a three-dimensional diagram of the annular clamp of the present invention;

[0037] Figure 4 is a front view of the annular fixture of the present invention;

[0038] Figure 5 is a schematic diagram of a welding track segment according to an embodiment of the present invention;

[0039] Figure 6 It is a schematic diagram of the intersection of adjacent welding trajectories in one embodiment of the present invention;

[0040] Figure 7 1 is a comparison diagram of weld surface formation and spatter between Example 1 of the present invention and Comparative Example 1;

[0041] Figure 8 is a comparison diagram of the post-weld deformation measurement of Example 1 of the present invention and Comparative Example 1;

[0042] Fig. 9 is a cross-sectional view of a weld according to Embodiment 1 of the present invention;

[0043] Fig.10 is a cross-sectional view of a weld according to Embodiment 2 of the present invention;

[0044] Fig.11 is a cross-sectional view of a weld according to Embodiment 3 of the present invention;

[0045] Fig.12 It is a cross-sectional view of the weld of Comparative Example 1 of the present invention.

[0046] Markings in the figure: first plate body 1, second plate body 2, third plate body 3, ear opening 4, positioning hole 5, annular clamp 6, base 601, bottom plate 602, quick clamp 603, pressing plate 604, rotation pin hole 605, notch 606, position pin hole 607, center axis 608;

[0047] The first welding track is 1#, the second welding track is 2#, the third welding track is 3#, the fourth welding track is 4#, and the welding tracks intersect and overlap at position A;

[0048] Figure 7 a represents the weld surface formation and spatter diagram of Example 1, Figure 7 b shows the weld surface formation and splash diagram of comparative example 1;

[0049] Figure 8 a represents the deformation measurement diagram after welding of Example 1, Figure 8 b shows the deformation measurement diagram after welding of comparative example 1. DETAILED DESCRIPTION

[0050] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0051] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "axial", "radial", "vertical", "horizontal", "inner", "outer" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "multiple" and "several" mean two or more, unless otherwise clearly and specifically defined.

[0052] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0053] like Figure 1-6 As shown, a preferred embodiment of a laser welding method for a hydrogen-producing pole frame plate of the present invention, the hydrogen-producing pole frame plate comprises a first plate body 1, a second plate body 2 and a third plate body 3, the first plate body 1, the second plate body 2 and the third plate body 3 are all provided with corresponding positioning holes 5, the second plate body 2 and the third plate body 3 are ring plates with an outer diameter of φ840mm and an inner diameter of 684mm, and the inner contours of the second plate body 2 and the third plate body 3 are provided with arc segments and ears 4; the method comprises the following steps:

[0054] S1: Place the annular fixture 6 on the workbench of the laser welding equipment, the annular fixture 6 includes a base 601 arranged on the workbench, a bottom plate 602 that can rotate relative to the base 601 around the central axis 608 of the base 601, a plurality of quick clamps 603 and two pressing plates 604 arranged at intervals around the top of the bottom plate 602, the bottom plate 602 and the base 601 are provided with a plurality of rotating pin holes 605 corresponding to the positioning holes 5, the pressing plate 604 and the bottom plate 602 are provided with a plurality of position pin holes 607 that give way to the hydrogen-producing pole frame plates, the pressing plate 604 is provided with a notch 606 corresponding to the shape of the ear 4, the laser welding equipment is provided with a driving motor for driving the bottom plate 602 to rotate, the driving motor is connected to the base 601, and the motor shaft of the driving motor is connected to the central axis 608;

[0055] S2: Open the quick clamp 603, place the first plate body 1 on the bottom plate 602, place the second plate body 2 on the first plate body 1, and align the positioning hole 5 with the rotating pin hole 605, insert the pin into the positioning hole 5 and the rotating pin hole 605 to quickly position the first plate body 1 and the second plate body 2, and limit the relative rotation of the bottom plate 602 and the base 601, place the notch 606 of the pressing plate 604 corresponding to the ear 4 on the second plate body 2, and then insert the pin into the positioning pin hole 607 to achieve the positioning of the pressing plate 604 and the bottom plate 602;

[0056] S3: After confirming that the first plate and the second plate are placed correctly, the force arm of the quick clamp 603 is lowered to press the first plate body 1 and the second plate body 2 onto the annular clamp 6, and ensure that the gap between the first plate body 1 and the second plate body 2 is less than 0.2 mm;

[0057] S4: Input laser welding parameters on the control interface of the laser welding equipment;

[0058] S5: Write the laser welding trajectory: divide the welding trajectory into four sections along the entire inner contour of the second plate body 2 in welding order: the first welding trajectory 1#, the third welding trajectory 3#, the second welding trajectory 2# and the fourth welding trajectory 4#, the first welding trajectory 1# and the fourth welding trajectory 4# are located opposite to each other and are arc-shaped, the third welding trajectory 3# and the fourth welding trajectory 4# are located opposite to each other and include the corresponding ear 4, the adjacent welding trajectories cross, intersect and overlap, and control the laser head of the laser welding equipment to move to the starting point of the first welding trajectory 1#;

[0059] S6: Turn on the protective gas blowing device coaxial with the laser head, and the protective gas is argon;

[0060] S7: Turn on the dust extraction mechanism located on the side axis of the laser head to remove welding fumes;

[0061] S8: The laser welding device controls the laser head to be located above the second plate body 2, and welds the second plate body 2 and one side of the first plate body 1 along the first welding track 1# according to the welding parameters;

[0062] S9: After the first welding track 1# is completed, the pin in the rotating pin hole 605 is removed, and the laser welding equipment controls the bottom plate 602 to rotate, driving the first plate 1 and the second plate 2 to move to the starting point of the second welding track 2# corresponding to the laser head, and the laser head welds the first plate 1 and the second plate 2 along the second welding track 2# according to the welding parameters;

[0063] S10: After the second welding track 2# is completed, the operation is the same as step S9, and welding is performed along the third welding track 3# and the fourth welding track 4# respectively, until the second plate body 2 and the first plate body 1 are fully welded;

[0064] S11: Loosen the force arm of the quick clamp 603, release the clamping of the first plate body 1 and the second plate body 2, remove the pin in the position pin hole 607, remove the pressing plate 604, and flip the welded first plate body 1 and the second plate body 2 as a whole, so that the second plate body 2 is located above the bottom plate 602 and the first plate body 1 is located above the second plate body 2;

[0065] S12: The operations are consistent with those in steps S2-S10. The third plate body 3 is positioned and clamped above the first plate body 1. The welding trajectory is divided into four sections in sequence along the entire circumference of the third plate body 3 according to the welding order. The laser head performs laser welding along the four welding trajectories in sequence above the third plate body 3 according to the welding parameters. When the third plate body 3 is welded to the other side of the first plate body 1 around the entire circumference, the electrode plate is obtained. The force arm of the quick clamp 603 is loosened to release the clamping of the electrode plate. The pin in the position pin hole 607 is removed, the pressure plate 604 is removed, and the electrode plate is removed.

[0066] Examples 1-3 and Comparative Example 1 were laser welded according to the above method and steps. The materials and thicknesses of the first plate body 1, the second plate body 2 and the third plate body 3 of Examples 1-3 and Comparative Example 1, the laser welding parameters, the parameters of the protective gas blowing device, and the electrode plate weld conditions are shown in Table 1 below:

[0067] Table 1

[0068]

[0069] As can be seen from Table 1 above, the double-sided laser welding used in the present invention can avoid the problems of wide weld width, large excess height, uneven surface, large welding deformation and large spatter caused by large arc heat input and unstable droplet transition in existing arc welding. The present invention can achieve a satisfactory melting depth under the condition of small heat input, thereby reducing the post-welding thermal deformation of the plate, which is conducive to reducing the difficulty of assembling the pole frame, and the welding speed can be increased from the arc welding speed of 900 mm / min to 50 mm / s.

[0070] From the above table 1 and attached Figure 7 It can be seen that by enhancing the shielding gas to avoid oxidation and porosity defects, controlling the shielding gas parameters to make the weld formation smooth and the spatter greatly reduced, cooperating with the dust extraction mechanism to remove the welding fume, and optimizing the laser welding parameters including welding power, welding speed and defocus, the synergistic effect of the laser welding parameters can not only reduce the spatter in the welding process, but also improve the welding efficiency, obtain a clean and tidy weld surface, and reduce the risk of film damage in subsequent processes.

[0071] From the above table 1 and attached Figure 8It can be seen that the present invention divides the welding trajectory into several sections according to the welding order along the entire inner contour of the second plate body 2 or the third plate body 3. The welding order of the section of the welding trajectory corresponding to the ear mouth 4 is later, and the adjacent sections of the welding trajectory intersect and overlap head to tail to ensure the airtightness of the weld and ensure that the welds of each section of the welding trajectory can be well connected. This improved welding process sequence can reduce welding deformation compared to the existing welding method of forming a whole circle in one go. The annular clamp 6 can effectively fix the pole plate and further reduce the post-welding deformation of the pole plate. The post-welding deformation of the pole plate is reduced from a single-sided warping of 23mm to a single-sided warping of ≤12mm, which can reduce the difficulty of the pole frame leveling process and the assembly of the pole frame after welding.

[0072] Since the weld surface appearance of Comparative Example 1 is unqualified, Fig.12 It can be seen that the height of the weld is relatively high when the weld is cut and measured. Figure 9-11 It can be seen that the present invention can obtain a weld with qualified weld width, excess height, and depth of penetration and a smooth appearance. The electrode plate weld width is 2 to 4 mm, and the excess height is less than 0.25 mm. This can avoid stress concentration causing a decrease in the dynamic load bearing capacity of the weld, and avoid large excess height and uneven surface that affect the flatness of the assembly when assembling the electrode frame.

[0073] The electrode plate of Example 1 was welded once according to the laser welding parameters to obtain a single weld, and the mechanical properties of two points on the single weld were measured. The first welding pass was performed on the single weld according to the laser welding parameters to obtain a double weld, and the mechanical properties of two points on the double weld were measured. The results are shown in Table 2 below:

[0074] Table 2

[0075]

[0076] From Table 2 above and attached Figure 9-11 It can be seen that the pressure bearing value of a single weld is much greater than 50MPa, and the pressure bearing value of a double weld is much greater than 100MPa, which indicates that laser welding is stable and much greater than the product requirement.

[0077] In summary, the present invention adopts a double-sided laser welding process under a segmented, head-to-tail overlapping, ear-mouth 4 welding sequence in a welding trajectory by replacing the welding heat source, the clamp supporting method and changing the welding process sequence, and cooperates with an annular clamp 6, appropriate laser welding parameters, strong gas protection and dust extraction, which can significantly improve the welding efficiency, and obtain qualified weld width, excess height, depth of penetration and a smooth and flat appearance without pore defects under low heat input, significantly reduce spatter and post-weld deformation of the electrode plate, improve weld quality, and help reduce the risk of subsequent film damage, simplify electrode frame processing, improve production efficiency, and reduce production costs.

[0078] The series of detailed descriptions listed above are only specific descriptions of feasible embodiments of the present invention. They are not intended to limit the scope of protection of the present invention. All equivalent embodiments or changes that do not deviate from the technical spirit of the present invention should be included in the scope of protection of the present invention.

Claims

1. A laser welding method for hydrogen production pole frame and pole plate, characterized in that: The methods include: The electrode plate to be welded comprises a first plate body, a second plate body and a third plate body, and the inner contours of the second plate body and the third plate body comprise ears; The welding track is divided into several sections according to the welding order along the inner contour of the entire circumference of the second plate body or the third plate body, and the welding order of the section of the welding track corresponding to the ear opening is the latter, and the adjacent sections of the welding track meet and overlap, specifically including: the welding track is divided into four sections along the inner contour of the entire circumference of the second plate body: the first section of the welding track and the second section of the welding track are located in opposite directions and are arc-shaped tracks, the third section of the welding track and the fourth section of the welding track are located in opposite directions and include tracks corresponding to the ear opening, and the welding order is: the first section of the welding track, the second section of the welding track, the third section of the welding track, and the fourth section of the welding track; the welding track is divided into four sections along the inner contour of the entire circumference of the third plate body, and the welding track and the welding order are consistent with those of the second plate body; The laser welding equipment completes the double-sided laser welding of the first plate body and the second plate body and the third plate body respectively along a plurality of welding tracks in a welding order, specifically comprising: after the laser head of the laser welding equipment completes the laser welding of the second plate body and one side of the first plate body above the second plate body, the second plate body and the first plate body are flipped over, so that the laser head completes the laser welding of the third plate body and the other side of the first plate body above the third plate body; The welding parameters include: welding power of 3600w~5400w, welding speed of 20~50mm / s, defocus of +25~-25mm, and obtaining the electrode plate.

2. A laser welding method for hydrogen production pole frame and pole plate according to claim 1, characterized in that: The materials of the first plate body, the second plate body and the third plate body include hot-formed steel and carbon steel. The thickness of the first plate body is 3-4 mm, the thickness of the second plate body is 1-2 mm, and the thickness of the third plate body is 1-2 mm.

3. The laser welding method for hydrogen production pole frame and pole plate according to claim 1, characterized in that: The first plate body, the second plate body and the third plate body are all provided with corresponding positioning holes (5); a ring clamp (6) is provided on the workbench of the laser welding equipment; the ring clamp (6) comprises a base (601) arranged on the workbench, a bottom plate (602) capable of rotating around a center relative to the base (601), a plurality of quick clamps (603) and a pressing plate (604) arranged at intervals around the top of the bottom plate (602); the bottom plate (602) and the base (601) are provided with a plurality of rotating pin holes (605) corresponding to the positioning holes (5); and the pressing plate (604) is provided with a notch (606) corresponding to the shape of the ear opening (4); When laser welding is performed along the first welding track, the electrode plate to be welded is clamped on the bottom plate (602) by inserting a pin into the positioning hole (5) and the rotating pin hole (605), and the quick clamp (603) and the pressure plate (604) are clamped, and relative rotation between the bottom plate (602) and the base (601) is restricted; before or after laser welding, the bottom plate (602) is rotated to drive the electrode plate to be welded to move to a position where the laser head of the laser welding equipment is located at the corresponding welding track.

4. The laser welding method for hydrogen production pole frame and pole plate according to claim 1, characterized in that: Before laser welding along the first welding track, the gap between the first plate body and the second plate body or between the first plate body and the third plate body is less than 0.2 mm.

5. The laser welding method for hydrogen production pole frame and pole plate according to claim 1, characterized in that: The laser head of the laser welding equipment is coaxially provided with a shielding gas blowing device. The parameters of the shielding gas blowing device during laser welding include: argon gas, gas flow rate: 15~25L / min, and the distance between the gas shielding nozzle and the welding surface: 8~10mm.

6. The laser welding method for hydrogen production pole frame and pole plate according to claim 1, characterized in that: A dust extraction mechanism is provided on the side axis of the laser head of the laser welding equipment, and the dust extraction mechanism is used to extract welding fumes during laser welding.

7. A laser welding method for hydrogen production pole frame and pole plate according to any one of claim 1, characterized in that: The surface of the electrode plate weld is flat and smooth, and the single weld pressure bearing value is >50MPa.

8. A laser welding method for hydrogen production pole frame and pole plate according to any one of claims 1 to 7, characterized in that: The width of the plate weld is 2~4mm, the excess height is <0.25mm, and the deformation after welding: single-side warping ≤12mm.

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