Welding method

Abstract

A welding method, comprising: forming a groove (2) on a member (1) to be welded; providing a gap maintaining structure (3) on the groove (2), the gap maintaining structure (3) protruding outward relative to the groove (2) so as to maintain a joint gap between the members (1) to be welded; and welding said members (1) to thoroughly melt weld joints between said members (1).

Description

Welding methods

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application is based on the Chinese patent application with application number 202311763694.X and application date December 20, 2023, and claims its priority. The disclosed content of the Chinese patent application is hereby introduced as a whole into this application. Technical Field

[0003] The present disclosure relates to the field of welding technology, and in particular to a welding method. Background Art

[0004] Welding is a common process in the machinery manufacturing industry. Due to the complexity of the welding process, welding quality control is particularly important. Generally, full penetration welds are required for key components.

[0005] The welding joints of engineering machinery in related technologies are mostly K-type grooves. Factors such as groove form, group gap, and interlayer cleaning affect the pass rate and quality stability of welding penetration, making it difficult to meet the demand for efficient full penetration welding technology.

[0006] Summary of the Invention

[0007] In view of this, an embodiment of the present disclosure provides a welding method that can reduce the difficulty of welding.

[0008] In one aspect of the present disclosure, there is provided a welding method, comprising:

[0009] Setting a groove on the first workpiece to be welded;

[0010] A gap maintaining structure is provided on the groove;

[0011] The first workpiece to be welded is set at the welding position of the second workpiece to be welded, and the first workpiece to be welded and the second workpiece to be welded are welded. During the welding process, the gap between the first workpiece to be welded and the second workpiece to be welded is maintained by the gap maintaining structure.

[0012] In some embodiments, the operation of placing the first workpiece to be welded at the welding position of the second workpiece to be welded, welding the first workpiece to be welded and the second workpiece to be welded, and maintaining the assembly gap between the first workpiece to be welded and the second workpiece to be welded by the gap maintaining structure during the welding process specifically includes:

[0013] Welding a first weld on the side of the first workpiece where the gap maintaining structure is provided, so that the molten pool formed by the first weld at least partially penetrates through the gap to the other side of the first workpiece;

[0014] A second weld is made on the other side of the first workpiece.

[0015] In some embodiments, the welding method further comprises:

[0016] In response to welding the first weld and the second weld, penetrating at least the root gap of the groove;

[0017] Filling welding and capping welding are performed on the first weld and the second weld to fully penetrate the gap between the first workpiece to be welded and the second workpiece to be welded.

[0018] In some embodiments, the welding method further comprises:

[0019] Before welding the first weld, tack welding is performed on the first workpiece to be welded and the second workpiece to be welded.

[0020] In some embodiments, the welding method further comprises:

[0021] Before performing tack welding, clean the surface and edges of the area to be welded.

[0022] In some embodiments, the welding method further comprises:

[0023] Before welding the second weld, clean the molten pool of the first weld and penetrate into the uneven area on the other side of the first welded part.

[0024] In some embodiments, the gap maintaining structure includes a boss protruding outward relative to the groove, and the first workpiece to be welded is configured to abut against the second workpiece to be welded via the boss during the welding process.

[0025] In some embodiments, the boss is disposed at a distance of 120 mm to 150 mm from the side edge of the first workpiece to be welded along the extension direction of the groove.

[0026] In some embodiments, the boss is disposed at a distance of 135 mm from the side edge of the first workpiece to be welded along the extension direction of the groove.

[0027] In some embodiments, the gap maintaining structure includes at least two bosses, and the interval between two adjacent bosses along the extending direction of the groove is 80 mm to 140 mm.

[0028] In some embodiments, the interval between two adjacent bosses along the extending direction of the groove is 130 mm.

[0029] In some embodiments, the width of the contact plane between the boss and the second workpiece to be welded along the extension direction of the groove is 8 mm to 12 mm.

[0030] In some embodiments, the width of the contact plane between the boss and the second workpiece to be welded along the extension direction of the groove is 10 mm.

[0031] In some embodiments, a height of a contact plane between the boss and the second workpiece to be welded relative to the groove along a normal direction of the contact plane is 1 mm to 3 mm.

[0032] In some embodiments, the height of the contact plane between the boss and the second workpiece to be welded relative to the groove along the normal direction of the contact plane is 2 mm.

[0033] In some embodiments, the groove is K-shaped, and the opening angle of the groove is 45° to 60°.

[0034] In some embodiments, the opening angle of the groove is 50°.

[0035] Therefore, according to the disclosed embodiment, by providing a groove and a gap-maintaining structure at the welding point of the workpiece to be welded, the gap between the components can be made to resist the effects of tensile stress during the welding process, maintaining the size of the gap and minimizing the situation in which the gap between the components gradually decreases due to tensile stress, resulting in the molten pool being unable to penetrate the weld through the other side. Compared to the existing technology, this eliminates the technical difficulty of relying on operators to manually ensure the welding gap, not only saving gap matching time and overcoming the technical problem of incomplete weld penetration caused by the gradual reduction of the gap between the components during the welding process, but also reducing the labor intensity of workers in weld repair, thereby improving welding efficiency and quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

[0037] The present disclosure can be more clearly understood from the following detailed description with reference to the accompanying drawings, in which:

[0038] FIG1 is a flow chart of a welding method according to some embodiments of the present disclosure;

[0039] FIG2 is a schematic structural diagram of a workpiece to be welded according to some embodiments of the welding method disclosed herein;

[0040] FIG3 is a schematic diagram of a partial structure of a workpiece to be welded according to some embodiments of the welding method disclosed herein;

[0041] FIG4 is a schematic structural diagram of workpieces to be welded according to other embodiments of the welding method disclosed herein.

[0042] It should be understood that the size of each part shown in the drawings is not drawn according to the actual proportional relationship.In addition, the same or similar reference numerals represent the same or similar components. DETAILED DESCRIPTION

[0043] Various exemplary embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings. The description of the exemplary embodiments is merely illustrative and is in no way intended to limit the present disclosure, its application, or use. The present disclosure can be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are provided to make the present disclosure thorough and complete and to fully convey the scope of the present disclosure to those skilled in the art. It should be noted that unless otherwise specifically stated, the relative arrangement of parts and steps, the composition of materials, numerical expressions, and numerical values ​​set forth in these embodiments should be interpreted as being merely exemplary and not as limiting.

[0044] The terms "first", "second" and similar terms used in this disclosure do not indicate any order, quantity or importance, but are only used to distinguish different parts. The terms "include" or "comprises" and similar terms mean that the elements before the term include the elements listed after the term, and do not exclude the possibility of also including other elements. The terms "upper", "lower", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0045] In the present disclosure, when a specific device is described as being located between a first device and a second device, an intervening device may or may not be present between the specific device and the first device or the second device. When a specific device is described as being connected to another device, the specific device may be directly connected to the other device without an intervening device, or may be not directly connected to the other device but with an intervening device.

[0046] All terms (including technical or scientific terms) used in this disclosure have the same meaning as those understood by one of ordinary skill in the art to which this disclosure belongs, unless otherwise specifically defined. It should also be understood that terms defined in, for example, general dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology, and should not be interpreted in an idealized or highly formal sense, unless explicitly defined herein.

[0047] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered part of the specification.

[0048] Welding is a common process in the machinery manufacturing industry. Due to the complexity of the welding process, controlling welding quality is particularly important. Full penetration welds are generally required for key components. However, welding joints in construction machinery often use K-grooves. Factors such as groove shape, joint clearance, and interlayer cleaning affect weld penetration rate and quality stability, making it difficult to meet the demand for efficient full penetration welding technology.

[0049] Some related technologies utilize the combined heat source effect of the laser beam and GMAW (Gas Metal Arc Welding) arc of gas metal arc welding. This method has more complex requirements for equipment performance and functions, and has high requirements for the workpiece processing dimensional accuracy and pre-welding assembly accuracy, which greatly limits its application and does not solve the problem of ensuring the weld gap during the welding process. In order to improve the engineering application adaptability of the laser-GMAW welding method, other related technologies first use GMAW arc to weld and fill the gap between the marine pipe assemblies, and then use laser-GMAW composite welding to remelt the first weld to achieve full penetration of the base. This method requires two welding steps to complete the base welding, and has more complex requirements for the assembly gap, equipment performance and functions. It also does not propose how to ensure the weld gap during the welding process. In view of this, in one aspect of the embodiments of the present disclosure, a welding method is provided, including but not limited to applications in products such as rotary drilling rigs and crane booms, which can reduce the difficulty of welding.

[0050] Figure 1 is a flow chart of a welding method according to some embodiments of the present disclosure, Figure 2 is a schematic structural diagram of a workpiece to be welded according to some embodiments of the welding method of the present disclosure, Figure 3 is a schematic structural diagram of a partial workpiece to be welded according to some embodiments of the welding method of the present disclosure, and Figure 4 is a schematic structural diagram of a workpiece to be welded according to other embodiments of the welding method of the present disclosure. With reference to Figures 1 to 4, the welding method includes: steps S1 to S3.

[0051] In step S1, a groove 2 is provided on a first workpiece 11 of two workpieces to be welded 1. The workpieces 1 may include the first workpiece 11 and the second workpiece 12. During welding, the second workpiece 12 may be placed on a horizontal surface or an operating plane. The first workpiece 11 may be placed at an angle to the second workpiece 12 according to welding requirements. The groove 2 may be provided on the first workpiece 11. The groove forms of the groove 2 include, but are not limited to, a K-shaped groove, a single V-shaped groove, a trumpet-shaped groove, and the like.

[0052] In step 2, a gap-maintaining structure 3 is provided on the groove 2 to maintain the gap between the first workpiece 11 and the second workpiece 12. The gap-maintaining structure 3 includes, but is not limited to, being disposed perpendicular to the plane of the groove 2 to better maintain the gap between the first workpiece 11 and the second workpiece 12. Steps 1 and 2 may be performed sequentially or simultaneously.

[0053] In step 3, the workpiece 1 to be welded is welded, and the first workpiece 11 to be welded is set at the welding position of the second workpiece 12 to be welded. During the welding process, the gap between the first workpiece 11 and the second workpiece 12 to be welded is maintained by the gap maintaining structure 3, so that the weld between the workpieces 1 to be welded is fully melted. During the welding process, due to the presence of the gap maintaining structure 3, the gap between the first workpiece 11 and the second workpiece 1 to be welded can be kept unchanged as much as possible, so that the weld pool is fully melted to the opposite side, ensuring that the weld between the workpieces 1 to be welded is fully melted. The welding process includes but is not limited to the process of welding the first weld. The complete penetration refers to but is not limited to the fact that the penetration depth of the weld is equal to the thickness of the workpiece 1 to be welded. L4 in Figure 4 is the height of the workpiece 1 to be welded.

[0054] In this embodiment, by providing a groove 2 and a gap maintaining structure 3 at the welding point of the workpiece 1 to be welded, the gap between the groups can be made to resist the effect of tensile stress during the welding process, maintain the size of the gap, and avoid as much as possible the situation where the gap between the groups is gradually reduced due to tensile stress, resulting in the inability of the molten pool to pass through the other side and penetrate the weld. Compared with the existing technology, the technical difficulty of relying on the operator to manually ensure the welding gap is eliminated, which not only saves the time of gap grouping, overcomes the technical problem of incomplete weld penetration caused by the gradual reduction of the gap between the groups during the welding process, but also reduces the labor intensity of workers' weld repair, improves welding efficiency and welding quality, and can be welded through using traditional welding processes. It can be applied to full penetration of welds of different lengths and specific groove forms to ensure the full penetration of the gap between the groups, and has good adaptability.

[0055] 2 and 3 , in some embodiments, when welding the workpiece 1, the first workpiece 11 is set at the welding position of the second workpiece 12, and the first workpiece 11 and the second workpiece 12 are welded, and the operation of maintaining the assembly gap between the first workpiece 11 and the second workpiece 12 by the gap maintaining structure 3 during the welding process specifically includes: welding a first weld on the side of the first workpiece 11 where the gap maintaining structure 3 is set, so that the molten pool formed by the first weld at least partially penetrates through the gap to the other side of the first workpiece 11, so that the first weld is fully penetrated. After the first weld is fully penetrated, a second weld is welded on the other side of the first workpiece 11 to complete the welding of the two sides of the first workpiece 11. The width of the molten pool formed by the first weld that penetrates through the gap to the other side of the first workpiece 11 includes but is not limited to 2 mm.

[0056] In this embodiment, the group gap is kept fixed by the groove 2 and the gap maintaining structure 3, and a first weld is welded on one side of the thickness direction of the first workpiece 11 to be welded, and the first weld extends along the length direction of the groove 2 to fill the gap between the first workpiece 11 to be welded and the second workpiece 12 to be welded, and the weld molten pool is completely melted into the groove of the first workpiece 11 on the other side of the thickness direction of the first workpiece 11 to be welded. On this basis, a second weld is welded on the other side of the thickness direction of the first workpiece 11 to be welded, and the second weld extends along the length direction of the groove 2. The weld molten pool penetrates the root gap area of ​​the first weld and the groove 2, achieving complete penetration on both sides of the workpiece 1 to be welded, meeting the requirements of full penetration backing welding of the gap under complex working conditions, significantly increasing the adaptability of welding to working conditions, and solving the problem of rework in the related technology that the weld molten pool of the group with small gap cannot be completely melted, which can greatly improve production efficiency, improve welding quality, and reduce rework workload, labor costs and scrap costs of unqualified rework.

[0057] In some embodiments, the welding method further includes: in response to welding the first weld and the second weld, at least the root gap of the groove 2 is melted through. Filling welds and capping welds are performed on the first weld and the second weld on the workpiece 1 to be welded, so that the gap between the first workpiece 11 and the second workpiece 12 is fully melted through. In this embodiment, the root area of ​​the groove 2 is melted through by the implementation of the first weld and the second weld, and then several welds between the first weld and the last weld are welded and filled by filling welds, and the last weld is welded by capping welds to obtain a full penetration weld of the groove 2, thereby ensuring the welding quality of each weld and ensuring that each weld is fully melted through.

[0058] With reference to Figures 2 to 4, in some embodiments, the welding method further includes: before welding the first weld, performing tack welding on the first workpiece 11 and the second workpiece 12 to secure the workpiece 1 at multiple, spaced weld points. Direction A in Figure 2 represents the direction of extension of the groove and / or the length of the first workpiece 11, and direction B in Figure 3 represents the thickness of the first workpiece 11. The thickness L5 of the workpiece 1 includes, but is not limited to, 30 mm, and the height L4 of the workpiece 1 includes, but is not limited to, 200 mm.

[0059] In this embodiment, before performing the first weld, spot welding can be performed between the first workpiece 11 and the second workpiece 12 to facilitate subsequent welding work, including but not limited to performing spot welding every 100 to 200 mm along direction A on the workpiece 1.

[0060] In some embodiments, the welding method further includes: cleaning the surface and edges of the area to be welded before performing tack welding. In this embodiment, before welding, the surface and edges of the area to be welded, including but not limited to performing tack welding, or the areas to be welded of the first workpiece 11 and the second workpiece 12 can be cleaned to improve welding quality.

[0061] In some embodiments, the welding method further includes: before welding the second weld, cleaning the uneven area where the molten pool of the first weld penetrates to the other side of the first workpiece to be welded 11. In this embodiment, there are uneven areas in the molten pool and / or weld on the other side of the first workpiece to be welded 11. Before welding the second weld, the uneven area where the molten pool of the first weld penetrates to the other side of the first workpiece to be welded 11, where the size and height are inconsistent or there are welding defects such as oxide scale, can be cleaned, so that the weld on the other side of the first workpiece to be welded 11 is in a polished, smooth and flat state, which facilitates improving the welding quality of the second weld and makes the welding process more efficient.

[0062] 2 , in some embodiments, the gap maintaining structure 3 includes a boss protruding outward relative to the groove 2 , and the first workpiece to be welded 11 is configured to abut against the second workpiece to be welded 12 via the boss during welding.

[0063] In this embodiment, the gap maintaining structure 3 can be set in the form of a boss. During the welding process, the first workpiece to be welded 11 is abutted against the second workpiece to be welded 12 through the upper surface of the boss, so that the upper surface of the boss and the second workpiece to be welded 12 are tightly attached without leaving any gap, so as to maintain the assembly gap between the first workpiece to be welded 11 and the second workpiece to be welded 12. The gap maintaining structure 3 can also be set to other forms that are convenient for processing.

[0064] Referring to Figure 2 , in some embodiments, the boss is positioned 120 to 150 mm from the side edge of the first workpiece 11 along the extending direction of the groove 2. In this embodiment, the distance L1 from the boss to the edge of the first workpiece 11 along direction A includes, but is not limited to, 120 to 150 mm. The value of L1 can be adjusted based on the actual welding product requirements and the size of the workpiece 1 to achieve optimal welding results.

[0065] 2 , in some embodiments, the boss is positioned 135 mm from the side edge of the first workpiece 111 along the extending direction of the groove 2. In this embodiment, the distance L1 from the boss to the edge of the first workpiece 11 along the A direction is preferably 135 mm to achieve better welding effect and quality.

[0066] Referring to Figure 2 , in some embodiments, the gap maintaining structure 3 includes at least two bosses, with the spacing between adjacent bosses along the extension direction of the groove 2 ranging from 80 mm to 140 mm. In this embodiment, to maintain a constant gap, the gap maintaining structure 3 includes at least two bosses, and the spacing L2 between adjacent bosses along the A direction can be selected to be 80 mm to 140 mm. The value of L2 can be adjusted based on the actual welding product requirements and the size of the weldment 1 to achieve better welding results.

[0067] 2 , in some embodiments, the interval L2 between two adjacent bosses along the extending direction of the groove 2 is 130 mm. In this embodiment, the interval L2 between two adjacent bosses along the extending direction of the groove 2 is preferably 130 mm to achieve better welding effect and quality.

[0068] Referring to Figure 2, in some embodiments, the width L3 of the contact plane between the boss and the second workpiece to be welded 12 along the extension direction A of the groove 2 is 8 mm to 12 mm. In this embodiment, the width L3 of the contact plane between the boss and the second workpiece to be welded 12 along the extension direction A of the groove 2 can be selected to be 8 mm to 12 mm. The value of L3 can be adjusted according to the actual welding product requirements and the size of the weldment 1 to achieve a better gap maintenance effect.

[0069] 2 , in some embodiments, the width of the contact plane between the boss and the second workpiece to be welded 12 along the extension direction A of the groove 2 is 10 mm. In this embodiment, the width L3 of the contact plane between the boss and the second workpiece to be welded 12 along the extension direction A of the groove 2 is preferably 10 mm to ensure reliable spacing during welding.

[0070] In some embodiments, the height of the contact plane between the boss and the second workpiece to be welded 12 relative to the groove 2 along the normal direction of the contact plane is 1 to 3 mm. In this embodiment, the height of the contact plane between the boss and the second workpiece to be welded 12 relative to the groove 2 along the normal direction of the contact plane is 1 to 3 mm. This height can be adjusted based on the gap requirements of the actual welding product group and the size of the weldment 1 to achieve better welding effects and welding quality.

[0071] In some embodiments, the height of the contact plane between the boss and the second workpiece to be welded 12 relative to the groove 2 along the normal direction of the contact plane is 2 mm. In this embodiment, the height of the contact plane between the boss and the second workpiece to be welded 12 relative to the groove 2 along the normal direction of the contact plane is preferably 2 mm to ensure a 2 mm assembly gap and a smooth transition of the R angle of the gap-maintaining structure 3. The R angle can be selected from 12.5° to 16°.

[0072] Referring to Figures 2 to 4 , in some embodiments, the groove 2 is K-shaped, and the angle X1 of the groove 2 is 45° to 60°. In this embodiment, the angle X1 of the groove 2 can be adjusted based on the gap requirements of the actual welding product group and the size of the weldment 1 to achieve better welding effects and quality.

[0073] 2 to 4 , in some embodiments, the opening angle X1 of the groove 2 is 50° to better meet welding production requirements.

[0074] 1 to 4 , taking K-type groove welding as an example, a full penetration welding process in some embodiments is provided:

[0075] Process the groove 2 and the gap maintaining structure 3 on the first workpiece 11 to be welded, clean the surface and edge of the welding part before welding, fix the gap between the weld group by the gap maintaining structure 3, and perform tack welding;

[0076] Rotating the workpieces 1 to a convenient welding angle so that the welding groove 2 faces upward, including but not limited to using MAG (Metal Active-Gas Welding) to weld the first pass, so that the first weld fills the gap between the workpieces 1 and the weld pool melts to the other side of the groove 2;

[0077] Rotate the workpiece 1 to a convenient angle for welding, with the welding groove 2 facing upward, and clean the uneven area at the root of the opposite weld groove 2, including but not limited to welding the second weld using MAG technology to achieve complete penetration at the root of the groove 2;

[0078] The workpiece 1 to be welded is rotated to an angle convenient for welding so that the welding groove 2 faces upward, including but not limited to using MAG technology to perform filling welding and cap welding to obtain a K-type groove full penetration weld.

[0079] Thus far, various embodiments of the present disclosure have been described in detail. To avoid obscuring the concept of the present disclosure, some details known in the art have not been described. Based on the above description, those skilled in the art can fully understand how to implement the technical solutions disclosed herein.

[0080] Although some specific embodiments of the present disclosure have been described in detail through examples, those skilled in the art will understand that the above examples are for illustration only and are not intended to limit the scope of the present disclosure. Those skilled in the art will understand that the above embodiments may be modified or some technical features may be replaced with equivalents without departing from the scope and spirit of the present disclosure. The scope of the present disclosure is defined by the appended claims.

Claims

1. A welding method, comprising: Providing a groove (2) on the first workpiece to be welded (11); A gap retaining structure (3) is provided on the groove (2); The first workpiece to be welded (11) is arranged at a welding position of the second workpiece to be welded (12), and the first workpiece to be welded (11) and the second workpiece to be welded (12) are welded. During the welding process, the gap between the first workpiece to be welded (11) and the second workpiece to be welded (12) is maintained by the gap maintaining structure (3).

2. The welding method according to claim 1, wherein the first workpiece to be welded (11) is arranged at a welding position of the second workpiece to be welded (12), the first workpiece to be welded (11) and the second workpiece to be welded (12) are welded, and during the welding process, the operation of maintaining the assembly gap between the first workpiece to be welded (11) and the second workpiece to be welded (12) by the gap maintaining structure (3) specifically comprises: Welding a first weld on one side of the first workpiece (11) where the gap retaining structure (3) is arranged, so that at least a portion of the molten pool formed by the first weld penetrates through the gap to the other side of the first workpiece (11); A second weld is welded on the other side of the first workpiece (11).

3. The welding method according to claim 2, further comprising: In response to welding the first weld and the second weld, at least a root gap of the groove (2) is melted through; Filling welding and capping welding are performed on the first weld and the second weld to fully penetrate the gap between the first workpiece (11) and the second workpiece (12).

4. The welding method according to claim 2 or 3, further comprising: Before welding the first weld, positioning welding is performed on the first workpiece (11) and the second workpiece (12).

5. The welding method according to claim 4, further comprising: Before performing positioning welding, clean the surface and edges of the area to be welded.

6. The welding method according to any one of claims 2 to 5, further comprising: Before welding the second weld, the molten pool of the first weld is cleaned and melted through to the uneven area on the other side of the first workpiece (11) to be welded.

7. A welding method according to any one of claims 1 to 6, wherein the gap retaining structure (3) comprises a boss protruding outwardly relative to the groove (2), and the first workpiece to be welded (11) is configured to abut against the second workpiece to be welded (12) via the boss during welding.

8. The welding method according to claim 7, wherein the boss is arranged at a distance of 120 mm to 150 mm from the side edge of the first workpiece to be welded (11) along the extension direction of the groove (2).

9. The welding method according to claim 7 or 8, wherein the boss is arranged at a distance of 135 mm from the side edge of the first workpiece (11) along the extension direction of the groove (2).

10. The welding method according to any one of claims 7 to 9, wherein the gap retaining structure (3) comprises at least two bosses, and the interval between two adjacent bosses along the extension direction of the groove (2) is 80 mm to 140 mm.

11. The welding method according to any one of claims 7 to 10, wherein the interval between two adjacent bosses along the extending direction of the groove (2) is 130 mm.

12. The welding method according to any one of claims 7 to 11, wherein the width of the contact plane between the boss and the second workpiece to be welded (12) along the extension direction of the groove (2) is 8 mm to 12 mm.

13. The welding method according to any one of claims 7 to 12, wherein the width of the contact plane between the boss and the second workpiece to be welded (12) along the extension direction of the groove (2) is 10 mm.

14. The welding method according to any one of claims 7 to 13, wherein the height of the contact plane between the boss and the second workpiece (12) to be welded relative to the groove (2) along the normal direction of the contact plane is 1 mm to 3 mm.

15. The welding method according to any one of claims 7 to 14, wherein the height of the contact plane between the boss and the second workpiece (12) to be welded relative to the groove (2) along the normal direction of the contact plane is 2 mm.

16. The welding method according to any one of claims 1 to 15, wherein the groove (2) is K-shaped, and the opening angle of the groove (2) is 45° to 60°.

17. The welding method according to any one of claims 1 to 16, wherein the opening angle of the groove (2) is 50°.

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