JPS6055222B2 - Butt welding method - Google Patents

Description

[Detailed description of the invention] This invention relates to a butt welding method.

Conventionally, in a butt welding method using a backing material, a steel end tab is used to prevent welding defects from occurring at both the start and end ends of the heat, or recently, a flux tab is used.

Such tabs are attached with bolts and nuts, or by welding, and have the disadvantage of being cumbersome to work with. Also, for aesthetic reasons, it was necessary to cut these tabs after welding was completed. This invention was made to improve the above-mentioned drawbacks, and it is possible to reduce the number of parts used. To provide a butt welding method which is easy to perform and can be performed at low cost. Next, a detailed explanation will be given based on the embodiment shown in the drawings.

The butt welding method according to the present invention is characterized in that a backing metal having bent portions at both ends is used, and welding is started and ended between the bent portions and the welded material.

<1> Back cover The back cover 1 is a plate-shaped member made of steel, and both ends thereof are bent in the same direction to form bent portions 12, 12, with a main portion 11 in the middle.

The length of the main portion 11 is made somewhat longer than the width of the material to be welded, which will be described later.

The bent portions 12, 12 at both ends of the backing metal 1 are bent so that the distance between the opposing bent portions 12, 12 becomes wider as they go toward their tips.

In the embodiment, the angle between the bent portions 12, 12 and the main portion 11 is approximately 6.
It was set at 50. The height of the bent portions 12, 12 is formed to be substantially the same as or slightly smaller than the height of the welded material, which will be described later.

<2> Installation of the material to be welded and the backing metal Fig. 1, Fig. 2, and Fig. 3 show an example of downward welding.

In FIG. 1, 2 is a column flange, and a flange 3 is welded to this column flange 2. A scallop web 4 is fixed to the scallop flange 3 at right angles. The entire length of the end to be welded of the cylindrical flange 3 is grooved and butted against the column flange 2 to form a V-shaped group 5.

The main part 11 of the backing metal 1 is brought into contact with the root surface of the flange 3.

If there is a threaded web 4, the threaded web 4 is cut out and the backing metal 1 is positioned below the group 5 so as to cover the root of the group 5 from below. Bent portion 12 of backing metal 1
, 12 are arranged at both ends in the width direction of the beam flange 3, which is the material to be welded, and project upwardly at some distance from both ends of the beam flange 3.

3) When starting welding, welding defects are likely to occur, so welding is started from the gap formed between the beam flange 3 and the bent portion 12 to form a bead.

Welding starts approximately perpendicular to the welding direction as shown in FIG. 2, gradually bends in the group 5 direction, and then continues welding along the welding direction. Since the bead is formed between the bent portion 12 and the welded material, it prevents the molten metal in the group 5 from flowing out.

4) Welding end Since welding defects are likely to occur at the welding end, welding is performed not only within the group 5 but also extending into the gap between the beam flange 3 and the bent portion 12.

Like the starting end, the welding end is formed into a bead so as to be gradually bent in the welding direction. If multi-layer welding is required, repeat the above steps to complete the welding work.

As described above, since the bent parts 12, 12 are formed at both ends of the backing metal 1, welding defects at the start and end ends can be removed from group 5 without using an end tab.
2 and 12 enable the formation of a bead and prevent the molten metal in group 5 from flowing out.

In addition, compared to a flat plate-shaped backing metal, it has a good appearance because both ends are bent, and there is no need to remove the backing metal after welding is completed.

5〉Other Examples. The above explanation was based on the case of downward welding, but Figures 4 and 5
As shown in the figure, the butt welding method according to the present invention can be carried out even in the case of horizontal welding. In other words, one end to the horizontal column flange 2! The beveled beam flange 3 is vertically erected and abutted against the side surface of the column flange 2, and the main part 11 of the backing metal 1 is brought into contact with the root surface of the beam flange 3.

The bent parts 12, 12 of the back metal plate 1 are bent toward the beam flange 3 side. In such horizontal welding, the bent portion 12 is attached to the upper surface of the column flange 2 along the bent portion 12 as shown by the arrow in FIG.
Welding starts from the gap between group 5 and beam flange 3.
to weld. At the welding end, welding continues along the bent portion 12 and then ends. Furthermore, the butt welding method according to the present invention can also be carried out in V-type group 5 as shown in FIGS. 6 and 7.

That is, in the same way as above, the backing metal 1 is brought into contact with the root surface,
In the gap between the bent portion 12 and the welded material, welding is performed left and right at right angles to the welding direction as shown by the arrows, and then group 5 is welded, and welding is similarly performed left and right at the terminal end. Since the butt welding method according to the present invention has the above configuration, the following effects can be obtained.

Since no 7-end tabs or flux tabs are used, the work can be done quickly and at low cost.

@ Since no welding is required to attach the end tab, there is no negative impact on the base metal.

(c) Even if an end tab or the like is used, welding defects at the welding start and end can escape to the bent part of the backing metal.

4. Since the back cover is bent, the appearance is good and there is no need to remove or cut the back cover after welding is completed.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of an embodiment of the butt welding method according to the present invention applied to downward welding, Fig. 2 is a plan view of a joint in downward welding, and Fig. 3 is a vertical cross-section of downward welding. Fig. 4 is a perspective view of one embodiment in which horizontal welding is performed, Fig. 5 is a plan view in the case of transverse welding, Fig. 6 is a plan view of another embodiment, and Fig. 7 is a 2 is a side view of the illustrated embodiment; FIG. 1...Backing metal, 2...Column flange,
3... Beam flange, 4... Beam web, 11... Main part, 12... Bent part.

Claims (1)

[Claims] 1. Contact the backing metal with bent parts at both ends to the root surface of the welded material, start welding in the gap between the bent part and the welded material, and start welding in the gap between the bent part at the other end and the welded material. A butt welding method characterized by finishing.