Shielded metal arc welding arc breaking transverse wiping welding method
Through the welding method of breaking arc and horizontal smear, weld defects caused by rapid cooling of the molten pool during the vertical welding position operation of the welding rod arc welding are solved, and good forming of the weld and welding quality are achieved.
Patent Information
- Application Number
- CN202510470237.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-15
- Publication Date
- 2025-06-06
AI Technical Summary
During the vertical welding position operation of welding rod arc welding, the rapid formation and cooling of the molten pool lead to the weld area being prone to defects such as weld tumors, unfusion, and undercuts, which affects the welding quality and the reliability and aesthetics of the welding structure.
The welding method of broken arc and horizontal smear is adopted to accurately control the combustion and extinguishing timing of the welding arc, combined with specific strip movements, improve the molten pool behavior, and reduce overheating and weld unevenness.
The welded vertical welding position bottom layer is significantly reduced, the welded edges, slag inclusions and weld tumor defects on both sides of the filler bevels are not fused, the welds are beautifully formed, and the internal and external welding quality is good, which improves welding efficiency and reliability.
Smart Images
Figure CN120095269A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of welding, in particular to a method for arc welding with a welding rod and breaking arc and horizontal wiping. Background Art
[0002] As a welding technology for special welding spatial positions, the vertical operation and feeding method of arc welding has shown unique process characteristics and challenges during its implementation. In this method, since the formation and cooling speed of the molten pool during welding are extremely rapid, this not only requires the welder to have superb operating skills, but also makes the fluidity of the molten pool particularly critical. However, it is this rapid thermal cycle process that often leads to weld nodule defects in the weld area. These defects not only affect the mechanical properties of the welded joint, but also reduce the overall welding quality, and it is difficult to achieve an ideal appearance.
[0003] In the field of welding at home and abroad, researchers and practitioners have explored a variety of wire feeding methods and measures for the two typical vertical welding positions of horizontal fixed pipe (2G) and plate butt vertical welding (5G), aiming to improve the welding quality of the vertical welding position. Unfortunately, most of these attempts are plagued by common problems such as lack of fusion and undercut. Lack of fusion refers to the failure of complete fusion between the weld metal and the parent material or weld metal, resulting in a cold weld; while undercut is due to improper welding parameters or operating errors, resulting in the arc "biting" off a part of the weld edge, resulting in the weld size not meeting the standard. These problems frequently occur in actual welding operations, seriously affecting the reliability and aesthetics of the welded structure.
[0004] In view of the above technical difficulties, after long-term on-site welding practice, repeated welding tests and in-depth theoretical analysis, an innovative arc-breaking and horizontal wiping welding method was born. This method effectively improves the behavior of the molten pool during the vertical welding process by precisely controlling the burning and extinguishing timing of the welding arc and combining specific arc-moving actions, namely "arc breaking" and "horizontal wiping". The arc-breaking technology can reduce the overheating problem caused by continuous welding, while the horizontal wiping action helps to evenly distribute the molten pool metal, promote the good formation of the weld, and reduce the occurrence of defects such as weld nodules, lack of fusion and undercuts.
[0005] The introduction of this arc welding method not only provides a new idea for solving the inherent problems of vertical welding, but also opens up a new way to improve welding quality, optimize weld appearance, and enhance the overall performance of welded structures. It is expected to play an important role in future on-site installation, equipment maintenance and overhaul welding, significantly improve the efficiency and reliability of welding operations, and promote the progress and development of welding technology. Summary of the invention
[0006] The object of the present invention is to provide a method for arc welding with broken arc and horizontal wiping to solve the problems raised in the above-mentioned background technology.
[0007] To achieve the above object, the present invention provides the following technical solutions: A method for arc welding with a welding rod and arc-breaking horizontal wiping comprises the following steps: Select a welding rod with low hydrogen coating, determine a DC welding device with a no-load voltage of more than 70V, connect the first workpiece to the positive electrode of the welding device, connect the welding clamp to the negative electrode, and there is a weld to be welded between the first workpiece and the second workpiece; Bottom-layer arc-breaking welding: The welding rod is placed at the root molten hole, and the arc is pressed down to strike the arc at the first arc-starting point at the root of the groove of the second workpiece. After the root of the groove on this side is melted through, the welding rod is moved straightly to the second workpiece on the other side to weld to the bottom-layer transition point at the root of the groove of the second workpiece and stays for the first preset time. After the root of the groove of the second workpiece is melted through, the welding rod is moved straightly to the first arc-strike side to weld to the first arc-extinguishing point at the root of the first arc-strike side of the groove of the second workpiece and stays for the second preset time to extinguish the arc. Then, the root of the previous molten hole is pressed down each time, and the process of horizontal wiping from left to right is repeated in sequence until the root welding is completed; Filling layer arc breaking connection: Ignite the arc at the second arc starting point on the left side of the root of the arc pit bottom layer weld. After the welding rod is short-circuited and contacts the molten pool, move the welding rod to the right side in a straight line to the transition point of the filling layer on the right side of the groove, and swing the welding rod slightly twice. Then move the welding rod to the left side in a straight line to the second arc extinguishing point at the root of the left side of the groove, and swing the arc slightly twice to extinguish the arc. Then press the root of the previous molten hole each time, and repeat in sequence, doing a left and right horizontal wiping process until the filling layer welding is completed; Arc breaking and connection of the cover layer: ignite the arc at the third arc starting point on the left side of the groove edge, short-circuit the welding rod and contact the molten pool, then move the welding rod to the right in a straight line to the transition point of the cover layer on the right side of the groove, and swing the welding rod slightly twice to melt the edge of the groove to the first set depth, then move the welding rod to the left in a straight line to the left side of the groove edge and swing it slightly twice to extinguish the arc, so that the edge of the groove melts the second set depth; then press the root of the previous molten hole each time, and cycle in sequence, doing a left-right horizontal wiping process until the cover layer welding is completed.
[0008] This solution can greatly reduce the phenomenon of unfused bottom layer in the vertical welding position, undercut on both sides of the filler cover groove, slag inclusion and weld nodule defects. The weld is beautiful in shape, the internal and external welding quality is good, the internal and external welding quality of the vertical welding position is guaranteed, and the equipment used is simple, the operation is flexible and convenient, and it is easy to master.
[0009] As a further solution of the present invention: the arc extinguishing welding operation frequency is controlled at 40 to 50 times / min.
[0010] As a further solution of the present invention: the first preset time is about 1 to 2 seconds.
[0011] As a further solution of the present invention: the second preset time is about 1 to 2 seconds.
[0012] As a further solution of the present invention: the first set depth is 0.5-1 mm.
[0013] As a further solution of the present invention: the second set depth dimension is 0.5-1 mm.
[0014] Compared with the prior art, the beneficial effects of the present invention are: it can greatly reduce the phenomenon of unfused bottom layer in the vertical welding position, undercut on both sides of the filling cover groove, slag inclusion and weld nodule defects, the weld is beautiful in shape, the internal and external welding quality is good, the internal and external welding quality of the vertical welding position is guaranteed, and the equipment used is simple, the operation is flexible and convenient, and it is easy to master. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Figure 1 The schematic diagram of the operation of the arc-breaking horizontal wiping welding method of the welding rod arc welding according to the embodiment of the present invention is as follows: Figure 1 .
[0016] Figure 2 The schematic diagram of the operation of the arc-breaking horizontal wiping welding method of the welding rod arc welding according to the embodiment of the present invention is as follows: Figure 2 .
[0017] In the figure: 1-first arc starting point, 2-bottom layer transition point, 3-first arc extinguishing point, 4-second arc starting point, 5-filling layer transition point, 6-second arc extinguishing point, 7-third arc starting point, 8-cover layer transition point, 9-third arc extinguishing point, 10-first workpiece, 11-second workpiece, 12-weld. DETAILED DESCRIPTION
[0018] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0019] Example 1 See also Figures 1-2 , a structural diagram of a method for arc welding with a welding rod provided in Example 1 of the present invention, comprising the following steps: S1. Select a welding rod with low hydrogen coating, determine a DC welding equipment with no-load voltage of more than 70V, connect the first workpiece 10 to the positive electrode of the welding equipment, connect the welding clamp to the negative electrode, and there is a weld 12 to be welded between the first workpiece 10 and the second workpiece 11; select a larger boost current and arc starting current, and the boost current and arc starting current are half of the boost current and arc starting current adjustment range on the welding equipment to improve the arc starting performance and the stability of arc burning, so as to increase the stiffness of the welding arc, facilitate the root forming, connect the filling cover weldment to the negative electrode, and connect the welding rod to the positive electrode to reduce the generation of pores. Choose a welding rod with low hydrogen coating, the slag solidifies quickly, and the weld is easier to form.
[0020] S2. Bottom-layer arc-breaking welding: the welding rod is placed at the root molten hole, and the arc is lowered to strike an arc at the first arc-starting point 1 at the root of the groove of the second workpiece 11. After the root of the groove on this side is melted through, the welding rod is moved in a straight line to the second workpiece 11 on the other side to weld to the bottom-layer transition point 2 at the root of the groove of the second workpiece 11 and stays for a first preset time. After the root of the groove of the second workpiece 11 is melted through, the welding rod is moved in a straight line to the first arc-strike side to weld to the first arc-extinguishing point 3 at the root of the first arc-strike side of the groove of the second workpiece 11 and stays for a second preset time to extinguish the arc. Then, the root of the previous molten hole is pressed each time, and the cycle is repeated in sequence, performing a left-right horizontal wiping process until the root welding is completed.
[0021] S3, arc breaking and connection of filling layer: ignite the arc at the second arc starting point 4 on the left side of the root of the arc crater base weld, short-circuit the welding rod and contact the molten pool, then move the welding rod in a straight line to the right to weld to the transition point 5 of the filling layer on the right side of the groove, and swing the welding rod slightly twice, then move the welding rod in a straight line to the left to weld to the second arc extinguishing point 6 at the root of the left side of the groove, and swing it slightly twice to extinguish the arc, then press the root of the previous molten hole each time, and repeat the cycle in sequence, doing a left and right horizontal wiping process until the filling layer welding is completed.
[0022] S4, arc breaking and connection of the cover layer: ignite the arc at the third arc starting point 7 at the edge of the left side of the groove, short-circuit the welding rod and weld it to the right side of the groove. The welding rod is slightly swung twice to melt the groove edge to the first set depth, and then move the welding rod to the left side of the groove. The arc is extinguished twice to melt the groove edge to the second set depth; then press the root of the previous molten hole each time, cycle in sequence, and do a left and right horizontal wiping process until the cover layer welding is completed. This arc extinguishing welding operation method is not easy to have defects such as weld nodules, undercuts and pores due to the fast cooling speed of the molten pool, small heat-affected zone, simple operation, good weld formation, and is particularly suitable for welding rod arc welding in the vertical welding position. The radiographic flaw detection has reached the pressure vessel assessment standard, and no weld cracking has occurred during the teaching test and on-site use.
[0023] The present invention can greatly reduce the phenomenon of unfused bottom layer in the vertical welding position, undercut on both sides of the filling cover groove, slag inclusion and weld nodule defects. The weld is beautiful in shape, the internal and external welding quality is good, the internal and external welding quality of the vertical welding position is guaranteed, and the equipment used is simple, the operation is flexible and convenient, and it is easy to master.
[0024] In some embodiments, the arc extinguishing welding operation frequency is controlled at 40 to 50 times / min.
[0025] In some embodiments, the first preset time is about 1 to 2 seconds.
[0026] In some embodiments, the second preset time is about 1 to 2 seconds.
[0027] In some embodiments, the first set depth is 0.5-1 mm.
[0028] In some embodiments, the second set depth is 0.5-1 mm.
[0029] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.
[0030] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.
[0031] 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 one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.
[0032] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.
[0033] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.
[0034] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.
Claims
1. A method for arc welding with broken arc and horizontal wiping, characterized in that: The steps include: Selecting a welding rod with a low hydrogen coating, connecting a first workpiece (10) to a positive electrode of a welding device, and connecting a welding clamp to a negative electrode, wherein a weld (12) to be welded is provided between the first workpiece (10) and a second workpiece (11); Bottom-layer arc-breaking welding: the welding rod is placed at the root molten hole, the arc is pressed down to strike the second workpiece (11), and after the root of the groove on this side is melted through, the welding rod is moved straightly to the second workpiece (11) on the other side to weld to the bottom-layer transition point (2) at the root of the groove of the second workpiece (11) and stays for a first preset time, and after the root of the groove of the second workpiece (11) is melted through, the welding rod is moved straightly to the first arc-strike side to weld to the first arc-extinguishing point (3) at the root of the groove of the second workpiece (11) and stays for a second preset time to extinguish the arc, and then the root of the previous molten hole is pressed down each time, and the process of horizontally wiping left and right is repeated in sequence until the root welding is completed; Filling layer arc breaking and connection: Ignite the arc at the second arc starting point (4), short-circuit the welding rod and contact the molten pool, then move the welding rod to the right in a straight line to the filling layer transition point (5) on the right side of the groove, and slightly swing the welding rod twice, then move the welding rod to the left in a straight line to the second arc extinguishing point (6) at the root of the left side of the groove, and slightly swing the welding rod twice to extinguish the arc, then press the root of the previous molten hole each time, and repeat the process of wiping left and right in sequence until the filling layer welding is completed; Arc breaking and connection of the cover layer: Ignite the arc at the third arc starting point (7), short-circuit the welding rod and contact the molten pool, then move the welding rod to the right side in a straight line to the transition point (8) of the cover layer on the right side of the groove, and slightly swing the welding rod twice to melt the edge of the groove to the first set depth, then move the welding rod to the left side in a straight line to the edge of the groove on the left side of the groove, and slightly swing the arc twice to extinguish the arc, so that the edge of the groove melts the second set depth; then press the root of the previous molten hole each time, and repeat in sequence, doing a left-right horizontal wiping process until the cover layer welding is completed.
2. The arc-breaking horizontal wiping welding method of electrode arc welding according to claim 1 is characterized in that: The welding equipment is a DC welding equipment with a no-load voltage of more than 70V.
3. The arc-breaking horizontal wiping welding method of electrode arc welding according to claim 1 is characterized in that: The step of striking the depressed arc on the second workpiece (11) comprises striking the depressed arc at a first arc starting point (1) at the root of the groove of the second workpiece (11).
4. The arc-breaking horizontal wiping welding method of electrode arc welding according to claim 1, characterized in that: The second arc starting point (4) is located at the left side of the root of the arc crater base weld.
5. The arc-breaking horizontal wiping welding method of electrode arc welding according to claim 1, characterized in that: The third arc starting point (7) is located at the groove edge on the left side of the groove.
6. The arc-breaking horizontal wiping welding method of electrode arc welding according to claim 1, characterized in that: The arc extinguishing welding operation frequency is controlled at 40 to 50 times / min.
7. The arc-breaking horizontal wiping welding method of electrode arc welding according to claim 2, characterized in that: The first preset time is 1 to 2 seconds.
8. The arc-breaking horizontal wiping welding method of electrode arc welding according to claim 3 is characterized in that: The second preset time is 1 to 2 seconds.
9. The arc-breaking horizontal wiping welding method of electrode arc welding according to claim 1, characterized in that: The first set depth is 0.5-1 mm.
10. The arc-breaking horizontal wiping welding method of electrode arc welding according to claim 5, characterized in that: The second setting depth dimension is 0.5-1 mm.