JPH09314374A - Joint welding method, and material to be welded - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a joint welding method of excellent strength and dimensional precision by which a groove part can be easily formed, members can be easily assembled, and excellent penetration can be obtained, and to provide a member to be welded. SOLUTION: A rugged surface 6c consisting of a plurality of projecting part 6b and a plurality of recessed parts 6a which are formed with equal intervals so as to be extended from a face of a plate-shaped member to its back surface is formed on one groove surface of a plate-shaped member 6, and the depth of the recessed part is smaller as approaching to the back surface side from the welding face side on the rugged surface. A corrugated side is formed in the plan view from the welding side of the plate-shaped member, and the side is rectangular in the plan view from the back surface side. A rugged surface 6c of the plate-shaped member 6 is abutted horizontally on the surface of a vertically arranged plate-shaped member, and the plate-shaped members are assembled in an orthogonal manner to each other. After assembly, welding is performed from the welding surface side of the plate-shaped member 6 along the welding seam.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a welding method applied to welding butt joints, corner joints, T joints, cruciform joints, and fitting joints of steel structures. The present invention relates to a welding method for a joint and a material to be welded, which can be carried out in accordance with the present invention and can improve the joint strength.

[0002]

2. Description of the Related Art FIG. 12 is a front view showing a groove portion of a conventional T-joint. As shown in FIG. 12, the vertical steel plate 1 and the horizontal steel plate 2 are assembled in a T-shape in a front view so as to vertically intersect with each other, and the front end surface 2 b of the steel plate 2 contacts the surface of the steel plate 1. Touching.

In the T-joint assembled as shown in FIG. 12, partial penetration welding is carried out by so-called fillet welding. As described above, in the case where the required joint strength is relatively low in the T joint, the tip surface 2b of one member (steel plate 2) is cut flat along the surface of the other member (steel plate 1). A groove can be machined only by using this.

However, in a T-joint having such a groove portion, although the member (steel plate 2) can be easily processed, it is difficult to secure a desired penetration depth during welding. , High joint strength cannot be obtained. Therefore, generally, in a steel structure or the like, at the time of welding a butt joint, a corner joint, a T joint, etc., in order to secure a good penetration depth and obtain a desired joint strength, at least one of After forming the slanted notch in the member, the joint is assembled and welded.

FIG. 13 is a front view showing the shape of another groove portion of the conventional T-joint. In the T-joint shown in FIG. 13,
On one end surface of the steel plate 4, an inclined notch 4a is formed so as to extend from the upper surface to the end surface. Then, similarly to the joint shown in FIG. 12, the vertical steel plate 3 and the horizontal steel plate 4
Are assembled in a T-shape in a front view so that and intersect vertically, and a groove-shaped groove portion 5 is formed at the open end thereof, and the tip surface 4b of the steel plate 4 is formed on the surface of the steel plate 3. Abutting.

As described above, when the inclined notch 4a is formed at the open end of the joint, deep penetration can be obtained at the time of welding, whereby high joint strength can be obtained.

[0007]

However, as shown in FIG.
In the case of processing the groove portion 5 as shown in, a step of flatly cutting the end surface 4b of one member (steel plate 4) along the other member (steel plate 3) and a step of forming the notch 4a There is a problem in that two steps are required. Therefore, in order to form the groove-shaped groove 5, as shown in FIG. 12, the tip surface 2b of the member (steel plate 2) is simply cut flat along the other member (steel plate 1). In comparison with the above case, the processing cost is double or more.

Furthermore, when welding a member having an inclined groove portion (inclined groove portion), it is relatively difficult to set welding conditions for obtaining a sufficient amount of a sufficient amount of extra layer in a single layer. .
That is, if welding is performed at the root portion (the contact portion between the end surface 4b of the steel plate 4 and the steel plate 3) under the condition that the molten metal does not burn through, the excess amount may be insufficient, so that a sufficient excess amount may be obtained. When the welding conditions are set, melt-through of molten metal easily occurs.

Further, as shown in FIG. 12, in the case where an inclined groove portion (inclined groove portion) is not formed, a root gap is generally provided between members in order to deepen the penetration. Has been applied. Therefore, in order to maintain the root gap with a uniform and appropriate width, it is necessary to perform tack welding while measuring and adjusting the gap or to dispose a spacer between the members in the process of assembling both members of the joint.

However, when such a method is used, it is difficult to form a uniform gap in a joint where the welding line is not straight. Further, when the partial penetration state is reached, there is no contact portion between the unwelded tip surface 2b of the steel sheet 2 and the steel sheet 1 or the contact portion is small, so shrinkage deformation occurs due to welding, and the dimensions The accuracy will be reduced. Further, the process of assembling the joint member becomes complicated, and when a spacer or the like is used, a member other than such a joint member is required, resulting in an increase in cost. Further, depending on the joint shape, it is extremely difficult to maintain an appropriate root gap.

The present invention has been made in view of the above problems, and does not require complicated assembling work of the welding base material, and increases the cost required for forming the groove portion or assembling the members. The welding method of a joint that can easily process the welding groove portion and can obtain a good penetration depth, thereby increasing the joint strength and performing welding with excellent dimensional accuracy. And an object to be welded.

[0012]

A welding method for a joint according to the present invention is one in which at least one groove surface of a material to be welded has an uneven shape along the welding line direction, the welding surface side is deep and the back surface side is shallow. Characterized by processing.

The material to be welded is a plate-shaped member, and it is preferable that the end face of the plate-shaped member is processed to have the uneven shape.

The material to be welded according to the present invention is characterized in that the groove surface is processed to have an uneven shape along the welding line direction, the welding surface side being deep and the back surface side being shallow.

It is preferable that a flat root surface is formed on the welding back surface side of the groove surface, and it is desirable that the space volume of the concave portion is larger than the volume of the convex portion. In addition, the groove and groove surface of the uneven shape includes a plurality of convex portions and a groove-shaped concave portion formed between the convex portions, and the convex portions may be formed so as to extend in a direction orthogonal to the welding line direction. it can. When the concave portions and the convex portions are alternately formed at regular intervals in a plan view, the distance P between the adjacent convex portions is 2 to 20 mm, and the angle α formed by the ridge line of the convex portion and the surface connecting the bottom surface of the concave portion. Is preferably 5 to 40 °. In addition, the convex portions are locally formed on the groove surface at a predetermined interval, and when the width W of the convex portions is 5 mm or less, the interval P between the adjacent convex portions is 50 mm or less, The angle α formed by the ridgeline of the convex portion and the surface connecting the bottom surface of the concave portion is preferably 5 to 20 °. Here, the ridgeline of the convex portion is a line connecting the vertices of one convex portion, that is, a tangent line between the convex portion formed on the material to be welded and a member abutting on the convex portion.

Further, it is preferable that the ridge line of the convex portion is formed so as to be inclined in the welding line direction on the groove surface, and the inclination angle θ thereof is −60 to 60 with respect to the direction orthogonal to the welding line.
It is desirable that the angle is °.

In the method of the present invention, since at least one groove surface of the material to be welded is processed by the processing of the uneven shape along the welding line direction and the welding is performed, the convex portion having a small heat capacity is melted relatively easily. Since the convex portion comes into contact with or comes close to the surface of another member, the concave portion locally acts as a root gap between the members, so that deep penetration can be obtained. Therefore, it is not necessary to maintain the root gap by temporary welding or spacers, and the assembly of members for welding becomes easy.

Further, since the welding surface side is deep and the back surface side is shallow in this uneven shape, it is possible to prevent the molten metal from melting through on the back surface side of the groove surface. That is, due to the mutual effect of the concave portion and the convex portion, it is possible to obtain a desired penetration depth and extra depth, and it is possible to obtain a welded portion that is close to full penetration without causing burn-through. Joint strength is improved. Further, when performing partial penetration welding, since the unwelded portion is in contact with the other member, it is possible to reduce welding shrinkage, and thereby to improve dimensional accuracy after welding.

Further, if the end face of the plate-shaped member is processed to have an uneven shape and the end face is brought into contact with another member to assemble and weld the joint, the assembly of the joint becomes easy.

According to the present invention, the groove surface of the material to be welded is processed to have an uneven shape along the welding line direction, the welding surface side being deep and the back surface side being shallow, so that this groove surface is When the members are brought into contact with each other and welded, the molten metal can be prevented from being burnt down, and a desired penetration depth and a desired depth can be obtained. Further, since the formation of the uneven surface and the cutting of the material to be welded can be performed at the same time, the groove surface can be processed at low cost.

In the present invention, on the welding back surface side of the groove surface,
When the flat root surface is formed, this root surface is brought into complete contact with the other member, so that the effect of preventing the molten metal from burning through is further improved. In addition, when the uneven surface is formed so that the space volume of the concave portion is larger than the volume of the convex portion, it is possible to secure an increase in the penetration depth, and the penetration depth varies depending on the position. Can be suppressed, and it becomes easy to prevent the overlap caused by the excess amount.

Furthermore, the groove and groove surface of the uneven shape is composed of a plurality of convex portions and groove-shaped concave portions formed between the convex portions, and the convex portions are formed so as to extend in a direction orthogonal to the welding line direction. By doing so, the uneven shape can be processed more easily. When the concave portions and the convex portions on the groove surface are alternately formed at a constant interval in a plan view, the interval α between the adjacent convex portions and the angle α formed by the ridge line of the convex portion and the surface connecting the bottom surface of the concave portion. Can be properly selected, but if the interval P is less than 2 mm, it is not practical because a sufficient penetration depth cannot be obtained or the processing becomes complicated. On the other hand, if the interval P exceeds 20 mm, the penetration depth will be insufficient, or the molten metal will burn through. Further, if the angle α is less than 5 °, the penetration depth becomes insufficient, and if the angle α exceeds 40 °, melt-through of molten metal occurs. Therefore, when the concave portions and the convex portions are alternately formed at regular intervals in a plan view, the distance P between the adjacent convex portions is 2 to 20 mm, and the surface connecting the ridge line of the convex portion and the bottom surface of the concave portion is formed. The angle α is preferably 5 to 40 °.

Although the convex portions may be locally formed at a predetermined interval on the groove surface, the width W of the convex portion is 5 m.
When it is less than or equal to m, the interval P between the adjacent protrusions is 50 mm.
If it exceeds, the penetration depth will be insufficient or the molten metal will burn through. In addition, if the angle α formed by the ridgeline of the convex portion and the surface connecting the bottom surface of the concave portion is less than 5 °, the penetration depth becomes insufficient, and if the angle α exceeds 20 °, the molten metal melts down. Occurs. Therefore, when the convex portions are locally formed at predetermined intervals on the groove surface and the width W of the convex portions is 5 mm or less, the interval P between the adjacent convex portions is 50 mm or less and the ridge line of the convex portions is It is preferable that the angle α formed by the surface connecting the bottom surfaces of the recesses is 5 to 20 °.

Further, when the ridgeline of the convex portion is formed to be inclined at the inclination angle θ with respect to the direction orthogonal to the welding line direction, the penetration depth can be increased and the welding current can be increased. However, the molten metal is less likely to burn through. At this time, if the inclination angle θ of the ridgeline of the convex portion exceeds 60 °, it is difficult to process the uneven surface, and the effect of preventing the molten metal from melting through is not improved, which is not preferable. Therefore, when the ridgeline of the convex portion is formed so as to be inclined with respect to the direction orthogonal to the welding line direction, the inclination angle θ is −6.
It is preferably 0 to 60 °.

[0025]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be specifically described below with reference to the accompanying drawings.

FIG. 1 is a perspective view showing a material to be welded for explaining a welding method for a joint according to a first embodiment of the present invention. 2A is a plan view showing a T-joint for explaining the welding method of the joint according to the first embodiment of the present invention, and FIG. 2B is a front view thereof.

As shown in FIG. 1, a plate member (material to be welded)
On one end face of the plate-shaped member 6, a plurality of convex portions 6b formed at equal intervals so as to extend from the front surface to the back surface of the plate-shaped member 6, and the convex portions 6
An uneven surface 6c composed of a plurality of recesses 6a formed between b
Are formed. Further, this uneven shape has a plate-like member 6
Is welded so that the front surface side is deep and the closer it is to the back surface, the shallower it is. In this embodiment, the uneven surface 6
The concavo-convex shape is processed so that the depth of the concave portion 6a becomes 0 mm when reaching the side 6d on the welding back surface side of c.

Then, as shown in FIG. 2, the uneven surface 6c of the plate member 6 is horizontally arranged on the surface of the plate member 7 arranged vertically.
And the plate-shaped member 7 and the plate-shaped member 6 are assembled in a T-shape in a front view so that the plate-shaped members 7 and 6 intersect vertically. Therefore, when viewed from above the plate-shaped member 6 in plan view, corrugated sides along the welding line direction are formed, and in plan view from the back surface side, it is rectangular.

After the joint 8 is assembled in this manner, the plate member 6 is welded from the welding surface side along the welding line of the uneven surface 6c. Then, the convex portion 6b on the welding surface side of the plate member 6 is formed.
Has a small heat capacity, it is relatively easily melted by welding heat, and the convex portions 6b come into contact with or come close to the surface of the plate-shaped member 7 so that the concave portions 6a are locally and plate-shaped. Since it acts as a root gap with the member 7, a deep penetration can be obtained. Further, the depth of the recess 6a becomes shallower as it approaches the back surface side, and the side 6d on the back surface side is completely in contact with the plate-shaped member 7, so that the molten metal can be prevented from being burned down. That is, the recess 6
Due to the mutual effect of a and the convex portion 6b, it is possible to obtain a desired penetration depth and extra depth, and it is possible to obtain a weld portion that is close to full penetration without causing burn-through. Therefore, the joint strength is improved.

Further, in this embodiment, since the groove surface of the plate member 6 can be cut and the uneven surface 6c can be formed at the same time, a desired groove can be obtained by only one step. Therefore, the processing cost of the groove can be reduced.
Further, since the members can be easily assembled and the spacer or the like is not necessary, it is possible to prevent the cost increase for that purpose.

Furthermore, the unwelded portion is made extremely small,
When trying to obtain a welded portion that is close to full penetration welding, the side 6d and the protrusion 6b that are in contact with the plate-shaped member 7 can prevent the molten metal from burning through. On the other hand, in the case of partial penetration welding, since the unwelded portion of the convex portion 6b is in contact with the plate member 7, shrinkage deformation due to welding is reduced.

FIG. 3 is a perspective view showing a material to be welded for explaining a welding method for a joint according to a second embodiment of the present invention. As shown in FIG. 3, on one end surface of the plate-shaped member (material to be welded) 9, a plurality of convex portions 9b formed at equal intervals so as to extend from the front surface of the plate-shaped member 9 to the vicinity of the back surface, Part 9b
An uneven surface 9c including a plurality of recesses 9a formed therebetween is formed. In the second embodiment, the plate member 9
The depth of the recess 9a becomes shallower from the upper surface toward the back surface, and the recesses and projections are processed so that the depth of the recess 9a becomes 0 mm near the welding back surface. The plate-shaped member 9 has a flat root surface 9d formed on the welding back surface side of the uneven surface 9c, and a corrugated side along the welding line direction is formed in a plan view from above the plate-shaped member 9. The shape is rectangular when viewed from the back side.

Also in the second embodiment having such a structure, as in the first embodiment shown in FIGS. 1 and 2, the plate-like member (not shown) arranged vertically is horizontally arranged on the surface thereof. When the uneven surface 9c of the plate-shaped member 9 is applied, assembled in a T shape in a front view so that these intersect perpendicularly, and welded along the uneven surface 9c, the same effect as the first embodiment can be obtained. You can Furthermore, in the second embodiment, since the root surface 9d is formed on the welding back surface side of the uneven surface 9c of the plate-shaped member 9, the effect of preventing the molten metal from burning through is further improved.

FIG. 4 is a perspective view showing a material to be welded for explaining a welding method for a joint according to a third embodiment of the present invention. On one end surface of the plate-shaped member 10, a plurality of convex portions 10 are formed so as to extend from the front surface to the back surface of the plate-shaped member (material to be welded) 10.
b are formed at equal intervals. As a result, the recesses 10a are formed between the plurality of protrusions 10b, but the interval P between the protrusions 10b is widened as compared with the first and second embodiments, so that the recesses 10a are formed. The plate-shaped member 10 is wide in the welding line direction. The recess 10a has a depth that becomes shallower from the welding front surface side of the plate member 10 toward the back surface side. In the present embodiment, the depth of the recess 10a is adjusted so that the depth of the recess 10a becomes 0 mm when reaching the side 10d on the welding back surface side of the uneven surface 10c.

As described above, also in the plate-shaped member 10 in which the convex portion 10b is locally formed, a joint is assembled in the same manner as in the first and second embodiments, and welding is performed along the welding line of the uneven surface 10c. By doing so, it is possible to obtain a desired penetration depth and extra depth, and it is possible to obtain a welded portion that is close to full penetration without causing burn-through.

FIG. 5A is a perspective view showing a material to be welded for explaining a welding method for a joint according to a fourth embodiment of the present invention, and FIG. 5B is a front view thereof. Similar to the first embodiment, on one end surface of the plate-shaped member (material to be welded) 11, a plurality of recesses 11a formed at equal intervals so as to extend from the front surface to the back surface of the plate-shaped member 11, A corrugated uneven surface 11c formed of a plurality of convex portions 11b formed between 11a is formed, and the depth of the concave portion 11a becomes shallower from the welding surface side of the plate-shaped member 11 toward the rear surface side. . In addition, when reaching the side 11d on the welding back surface side of the uneven surface 11c, the uneven surface 1 has a depth of 0 mm.
1c is formed. The fourth embodiment has an uneven surface 1
When 1c is brought into contact with another member, the ridgeline (tangent line with another member) 11e of the convex portion 11b which is in contact with the member 1c has an uneven surface 1
1c is different from the first embodiment in that it is inclined in the welding line direction.

As described above, in the uneven surface 11c, the ridgeline 11e of the convex portion 11b is inclined in the welding line direction to process the uneven shape, and when the joint is assembled and welded by the plate-like member 11, the concave portion of the uneven surface 11c is formed. Compared with the case where the lines of 11a and the convex portion 11b are orthogonal to the welding line, the effect of preventing the molten metal from burning through is improved even under high welding current conditions. Therefore, the fourth embodiment is effective for a joint that requires penetration close to complete penetration.

In the first to third embodiments of the present invention, the example of the T-joint is shown. However, similar effects can be obtained also in a butt joint, a corner joint, a cross joint and a fitting joint.

[0039]

EXAMPLES Examples of welded joints obtained from the material to be welded according to the present invention will be specifically described below in comparison with comparative examples.

First, a T-joint was welded by a welding method using the material to be welded according to the first embodiment of the present invention and a conventional welding method, and a penetration depth comparison test was carried out.

FIG. 6 is a front view showing the size of the T-joint used in the penetration depth comparison test. Further, FIG. 7A is a plan view showing the size of the plate member used as an example, and FIG. 7B is a front view thereof.

As a comparative example, as shown in FIG. 6, a plate-shaped member 13 having a plate thickness of 14 mm and a plate-shaped member 14 having a plate thickness of 12 mm were prepared, and the plate-shaped member 13 arranged vertically was prepared. The flat end surface 1 of the plate-shaped member 14 is formed on the surface of the plate-shaped member 13 so that the plate-shaped member 14 arranged horizontally intersects vertically.
The T-joint assembled by applying 4a was used. The plate-shaped member 14 was arranged so that its upper surface was located 12 mm from the upper end surface 13 a of the plate-shaped member 13.

Further, as an example, the plate member 6 as the material to be welded according to the first embodiment was used in place of the plate member 14 shown in FIG. That is, as shown in FIG. 7, on one end surface of the plate-shaped member 6, a wavy uneven surface 6 including a convex portion 6 b extending from the front surface to the back surface of the plate-shaped member 6 and a concave portion 6 a.
c is formed, and the depth of the concave portion 6a becomes shallower from the welding front side to the back side of the plate-shaped member 6, and the side 6
At d, the depth of the recess 6a is 0 mm.

Then, the plate-like member 6 is formed on the surface of the plate-like member 13.
The joint was assembled by bringing the convex portions 6b of the above into contact. In the present embodiment, the plate member 6 has a plate thickness of 12 mm, the interval P between the adjacent convex portions 6b is 8 mm, the surface 6f connecting the bottom surfaces of all the concave portions 6a, and the ridge line 6e of the convex portion 6b. The angle α formed by and is set to 20 °.

Welding is performed by welding three kinds of welding conditions to such two kinds of T joints, and after welding, a cross-section macro is taken from the welded portion and the root thickness of the unwelded portion is measured. The depth was evaluated. However, for the welding, a wire with a diameter of 1.4 mm is used, and (Ar + 20% CO ₂ )
Automatic MAG welding using gas as a shielding gas was used. The welding conditions at this time are shown in Table 1 below, and the evaluation results are shown in Table 2 below.

[0046]

[Table 1]

[0047]

[Table 2]

As shown in Tables 1 and 2 above, when welding is performed by the method of this embodiment, under any welding condition,
Compared with the comparative example, the root length of the unwelded part was reduced. That is, the penetration depth was increased and a good welded joint could be obtained.

Then, in Example No. 3 and Comparative Example No.
A bending fatigue test was performed using the T joint of No. 6 as a bending fatigue test piece.

FIG. 8 (a) is a side view showing the shape and size of a test piece for a bending fatigue test, and FIG. 8 (b) is a front view thereof. In FIG. 8, the plate member 13 is a member D,
The plate-shaped members 6 and 14 of FIGS. 6 and 7 will be described as a member E.

As described above, the member D and the member E are assembled in a T shape so as to vertically intersect with each other and welded,
Weld metal 20 is formed in the groove. Members D and E have a longitudinal length of 120 mm and a width of 50 mm.
And Further, the member D is provided with fixing holes 19 penetrating therethrough at four places, and fixing jigs (not shown) are inserted into these fixing holes 19, and the fixing jigs are fixed by a fixing device (not shown). The member D is fixed by tightening it. Further, the member E has a strain gauge 23 attached to the front surface and the back surface at the center of the plate width at a position 20 mm away from the end surface on the member D side.

In the thus-prepared test piece, after fixing the member D, the unwelded end 25 of the member E
On the other hand, a repetitive stress was applied to the member D in the parallel direction, a repetitive bending stress was set based on the strain applied to the strain gauge 23, and the number of repetitive fractures at a stress amplitude of 16 kgf / mm ² was compared. The evaluation results of this bending fatigue test are shown in Table 3 below.

[0053]

[Table 3]

As shown in Table 3 above, Example No. No. 3 is Comparative Example No. Compared with 6, the number of repeated fractures increased. That is, according to the present invention, the bending fatigue strength of the welded joint can be increased.

Next, a plate-shaped member 9 having the shape shown in the second embodiment shown in FIG. 3 is prepared, and the uneven surface 9c of the plate-shaped member 9 is attached to the end surface of the plate-shaped member on which the uneven surface is not processed. The butt joint was assembled by hitting, and the butt joint was welded under the conditions shown in Table 4 below to evaluate the appearance and penetration of the beads.

FIG. 9A is a plan view showing the size of the plate member 9 shown in the second embodiment, and FIG. 9B is a side view thereof. In this embodiment, the plate thickness is 12 mm,
The root width of the root surface 9d is 1 mm, and the angle α formed by the ridgeline 9e of the convex portion 9b and the surface 9f connecting the bottom surface of the concave portion 9a.
And the interval P between the adjacent convex portions 9b was changed, and various intervals P and angles α were evaluated. However, the interval P between the protrusions 9b and the width of the protrusions 9b were set so that the spatial volume of the recesses 9a was larger than the volume of the protrusions 9b.

The evaluation results are shown in Table 5 below. In Table 5 below, ◯ (pass) indicates that the penetration depth is increased by 20% or more of the plate thickness and the surface is under-exposed as compared with the penetration depth of the conventional butt welding in which the groove surface is flat. Filling did not occur and the molten metal did not burn through. Further, △ indicates that there was a rejected part depending on the welding position, × indicates that the penetration depth did not satisfy the acceptance criteria, and XX indicates that burn-through of the molten metal occurred, − Indicates that the process for processing the uneven surface was complicated, and therefore was not performed.

[0058]

[Table 4]

[0059]

[Table 5]

As shown in Table 5 above, the surface 9f and the ridgeline 9e
The penetration depth increased when the angle α formed by and was 5 ° or more and the pitch was 2 mm or more. On the other hand, under the conditions of this embodiment, the angle α formed by the surface 9f and the ridgeline 9e exceeds 40 °, and the interval P between the convex portions is 20.
If it exceeds mm, the penetration is insufficient or the molten metal is liable to burn through.

Furthermore, the plate-like member (material to be welded) shown in the third and fourth embodiment methods shown in FIGS. 4 and 5 is prepared, and the uneven surface of this plate-like member is processed into an uneven surface. The appearance and penetration of the bead were evaluated by assembling the joint by applying it to the end face of the plate-shaped member that was not present and welding the butt joint.

FIG. 10A is a front view showing the size of the plate member 10 shown in the third embodiment, and FIG. 10B is a side view thereof. As described above, the plate-shaped member 1 shown in FIG.
0 indicates that the interval P between the convex portions 10b is wide, and the concave portion 10a is formed wide in the welding line direction of the plate member 10. In the present embodiment, the width W of the convex portions 10b, the interval P between the convex portions 10b, and the surface 1 that connects the bottom surface of the concave portion 10a.
The angle α formed by 0f and the ridgeline 10e of the convex portion 10b was changed, and various widths W, intervals P and angles α were evaluated.

As a result, when the width W of the convex portion 10b is set to 5 mm or less, the angle α formed by the surface 10f connecting the bottom surface of the concave portion 10a and the ridge line 10e of the convex portion 10b is 5 to 20 °.
When the distance P between the protrusions 10b was 50 mm or less, the evaluation results of the bead appearance and the penetration state were acceptable.

FIG. 11 is a front view showing the size of the plate member 11 shown in the method of the fourth embodiment. As described above, in the plate-shaped member 11, when the uneven surface 11c is brought into contact with another plate-shaped member, the ridgeline 11e of the convex portion 11b in contact with this is inclined at the inclination angle θ in the welding line direction. There is. In this embodiment, the interval P between the convex portions 11b is 8 mm, the angle α formed by the surface 11f connecting the bottom surfaces of the concave portions 11a and the ridgeline 11e of the convex portion 11b is 20 °, and the inclination angle θ and the current of the ridgeline 11e are set. The conditions were changed and various tilt angles θ and current conditions were evaluated.

As a result, when the ridgeline 11e is formed in the direction orthogonal to the welding line of the plate-like member 11 (inclination angle α
= 0 °), the molten metal was less likely to burn through even if the welding current was increased. Therefore, the plate-shaped member 11 having the uneven surface 11c having such a shape is effective for a joint that requires a near-perfect penetration. However, if the inclination angle θ of the ridgeline 11e of the convex portion 11b exceeds 60 °, it is not preferable because it is difficult to process the uneven surface and the effect of preventing the molten metal from melting through is not improved.

[0066]

As described above in detail, according to the method of the present invention, at least one groove surface of the material to be welded is processed into an uneven shape along the welding line direction, and this uneven shape is deep on the welding surface side. Since the back side is formed to be shallow and welded, a welded joint with high joint strength can be obtained by deep penetration without forming an inclined notch, and melt-through of molten metal can be prevented. This makes it possible to easily perform processing and assembly for welding at low cost.
Further, since the convex portion is brought into contact with another member and welded, welding shrinkage can be prevented even in the case of partial penetration welding,
The dimensional accuracy after welding can be improved. Further, if a flat root surface is formed on the welded back surface side of the groove surface, it is possible to further prevent the molten metal from burning through.

Furthermore, the grooved surface processed into the concavo-convex shape comprises a plurality of convex portions and groove-shaped concave portions formed between the convex portions, and the surface connecting the bottom surfaces of the concave portions and the convex portion. If the angle formed by the ridgeline and the interval between the convex portions is properly regulated, or if the ridgeline of the convex portion is formed to be inclined on the uneven surface, the inclination angle thereof is appropriately regulated to further improve the welded joint. And the joint strength can be improved.

[Brief description of drawings]

FIG. 1 is a perspective view showing a material to be welded for explaining a welding method for a joint according to a first embodiment of the present invention.

FIG. 2A is a plan view showing a T-joint for explaining the welding method for the joint according to the first embodiment of the present invention,
(B) is the front view.

FIG. 3 is a perspective view showing a material to be welded for explaining a welding method for a joint according to a second embodiment of the present invention.

FIG. 4 is a perspective view showing a material to be welded for explaining a welding method for a joint according to a third embodiment of the present invention.

5A is a perspective view showing a material to be welded for explaining a welding method for a joint according to a fourth embodiment of the present invention, FIG.
(B) is the front view.

FIG. 6 is a front view showing the size of a T-joint used in a penetration depth comparison test.

7A is a plan view showing the size of a plate-shaped member used as an example, and FIG. 7B is a front view thereof.

FIG. 8A is a side view showing the shape and size of a bending fatigue test piece, and FIG. 8B is a front view thereof.

FIG. 9A is a plate-shaped member 9 used in this example.
2B is a plan view showing the size of FIG. 3B, and FIG.

10A is a front view showing the size of the plate member 10 shown in the third embodiment, and FIG. 10B is a side view thereof.

FIG. 11 is a front view showing the size of the plate-shaped member 11 shown in the fourth embodiment.

FIG. 12 is a front view showing a groove shape of a conventional T-joint.

FIG. 13 is a front view showing another groove shape of the conventional T joint.

[Explanation of symbols]

 1, 2, 3, 4; Steel plate 4a; Notch 5; Groove portion 6, 7, 9, 10, 11, 13, 14; Plate-shaped member 6a, 9a, 10a, 11a; Recessed portion 6b, 9b, 10b, 11b; convex portions 6c, 9c, 10c, 11c; concave and convex surfaces 6d, 10d, 11d; sides 6e, 9e, 10e, 11e; ridge line 8; joint 9d; root face 19; fixing hole 20; weld metal 23; strain gauge

Claims (10)

[Claims] 1. A groove surface of at least one of the materials to be welded,
A welding method for a joint, characterized in that an uneven shape along the welding line direction, which has a deep front surface side and a shallow rear surface side, is processed. 2. The method for welding a joint according to claim 1, wherein the material to be welded is a plate-shaped member, and the end surface of the plate-shaped member is processed to have the uneven shape. 3. A material to be welded, characterized in that the groove surface is processed to have an uneven shape along the direction of the welding line and having a deep welding front surface side and a shallow back surface side. 4. The welded material according to claim 3, wherein a flat root surface is formed on the welding back surface side of the groove surface. 5. The material to be welded according to claim 3, wherein the space volume of the concave portion of the grooved surface of the uneven shape is larger than the volume of the convex portion. 6. The concave-convex groove surface comprises a plurality of convex portions and groove-shaped concave portions formed between the convex portions, and the convex portions extend in a direction orthogonal to the welding line direction. It is formed, The to-be-welded material of any one of Claim 3 thru | or 5 characterized by the above-mentioned. 7. When the concave portions and the convex portions are alternately formed at a constant interval in plan view, the interval P between the adjacent convex portions is 2 to 20 mm, and the ridgeline of the convex portion and the bottom surface of the concave portion are connected. The material to be welded according to claim 6, wherein an angle α formed by the surface is 5 to 40 °. 8. The convex portion is locally formed on the groove surface at a predetermined interval, and the width W of the convex portion is 5 m.
When it is m or less, the interval P between the adjacent protrusions is 50 mm.
The material to be welded according to claim 6, wherein an angle α formed by a ridgeline of the convex portion and a surface connecting the bottom surface of the concave portion is 5 to 20 °. 9. The uneven groove surface is composed of a plurality of convex portions and groove-shaped concave portions formed between the convex portions, and ridge lines of the convex portions are formed to be inclined in a welding line direction. The material to be welded according to any one of claims 3 to 5, characterized in that 10. The material to be welded according to claim 9, wherein the inclination angle θ of the ridgeline of the convex portion is −60 to 60 ° with respect to the direction orthogonal to the welding line.