JPS61199584A - High frequency butt welding method - Google Patents

Abstract

PURPOSE:To reduce remarkably welding defects and to increase product yield by rolling with the specified rolling reduction quantity by rolling roll with forming a forming part on the center part of flange material and by welding a web material with forming a bulging part. CONSTITUTION:A flat projecting part 11 is formed on the center part of a flange material 1 by rolling with the rolling reduction of 3-20% of the plate thickness of the flange 1 by rolls 13, 32. A high frequency welding is performed by butting to the flat projecting part 11 of the flange 1 the end part of the web material 2 without performing any working thereon. By forming a bulging part on the weld zone of the flange like this a high frequency current is concentrated on the forming part 11 and the part thereof is heated at higher temp. compared with others.

Description

Detailed Description of the Invention (a) Industrial Application Field The present invention relates to a high-frequency butt welding method using flange upsetting. Here, flange upsetting is a process in which a protrusion is formed by rolling a flange material. It means to form.

(B) Prior Art A conventional method for manufacturing high-frequency butt welded H-beam steel is shown in FIG. 2. (A) shows a method of welding by simply butting the flange material and the web material together. In this method, the entire flange material must be heated to the welding temperature, so a large amount of scale is generated on the flange material, and the peas at the welded portion flow out laterally as shown in FIG. 4(A). However, this is still considered to have a good peed appearance. In this case, the penetration of the flange material is small (there is a problem in terms of strength).

Therefore, in order to increase the strength of the welded part, a method has been proposed in which the ends of the web material are formed into a shape that widens toward the end ((B)
figure). However, even with this method, if the absorbing force is increased and overheating occurs, irregular peads as shown in FIG. 4(B) will occur. When such a speed occurs, welding power efficiency decreases and power consumption becomes significantly worse.

Furthermore, if there are many protrusions on the bead, unpainted areas will be created when the bead is unpainted, and corrosion will occur from these areas.

To ensure the strength of the weld and improve the bead shape,
The applicant proposed that the end of the web material be formed into a special shape (Fig. 2 (C)) (Japanese Patent Application No. 74029/1983).
. However, even with this shape, it is necessary to heat the entire flange material to the welding temperature, and problems such as scale generation and insufficient penetration of the flange portion are not solved.

(c) Problem to be solved by the invention The problem to be solved by the invention is to intensively heat only the welded part of the flange material, improve the bead shape, and improve the strength of the welded part. The objective is to obtain a high-frequency butt welding method that can be used.

B) Means for Solving Problems The high-frequency butt welding method of the present invention involves forming a processing-forming part in the center of the flange material, and applying the processing-forming part to the flange material with a thickness of 3 to 20 mm using a rolling roll. By rolling with a reduction amount of 1, forming the bulging part, and performing high frequency welding by butting the end of the web material against the processed and formed part,
The above problems have been resolved.

By forming a bulge in the welded portion of the flange material, the high-frequency welding current is concentrated on the bulge due to the proximity effect just before welding when the web material approaches, resulting in a high temperature. Furthermore, heat is transferred to the base material (the entire flange material) from the heated bulge.
Since the surface where the material is diffused is also smaller than when it is flat, local heating occurs and unnecessary portions do not melt or protrude.

(e) Examples The method of the present invention will be explained with reference to FIG.

In the method of the present invention, a flat convex portion 11 (Figures (A) and (B)) and a curved concave portion 12 are provided at the center of the flange material 1.
(Figure (C)) and curved convex portion 13 (Figure (D)) are formed.

The ends of the web material 2 are brought into contact with these processed and formed parts 11, 12, and 13.

In the figure (A), the end of the web material 2 is simply butted against the flat convex portion 11 of the flange material 1 without any processing.

In the figure (B), the end of the web material 2 is formed into a flared portion 211, which is butted against the flat convex portion 11 of the flange material 1.

(C) In the figure, the fullerage material 1 is attached to the end of the web material 2.
The curved end widening portion 22 of the curved concave portion 12 is formed.
match against. The recess 12 and the portion 22 have shapes that allow them to fit into each other.

In the figure (D), a curved end widening portion 22 is formed at the end of the web material 2, and it is connected to the curved convex portion 1 of the flange material 1.
Match it to 3. In this embodiment, the flange material 1
is curved upward into a V-shape, and a recess 14 is provided on the opposite side of the curved convex portion 13.

These working and forming parts 11, 12, 13 are formed by press rolls shown in FIGS. 5 to 7.

The rolls 31, 32 shown in FIG. 5 are shown in FIG. 1(A).

It is suitable for forming the flat convex portion 11 shown in (B).

The rolls 33, 34 shown in FIG. 6 are suitable for forming the curved recess 12 shown in FIG. 1(C). The rolls 35, 36 shown in FIG. 7 are suitable for forming the curved projections 13 and depressions 14 shown in FIG. 1 CD).

In the case shown in FIG. 1(D), after welding and joining, the flange material 1 is flattened by horizontal rolls. In this example, the convex portion 13 and the concave portion 14 are easily formed, the welding strain and the correction direction are the same, so correction is easy, and the welded portion after correction is well bonded. It is preferable that the reduction amount by the rolling roll is set to 3 to 20 inches of the thickness of the flange material. Although it is possible to perform cold processing, hot or warm processing allows a good bulge shape to be obtained with a smaller rolling force.

(F) Specific Example I Height: 2001111% Width: 100m+, Web Thickness: 3.21
When manufacturing an H-section steel with a 1111 flange thickness of 4.5+m+, a 0.3 mm bulge was formed in the center of the flange by the processing method of the present invention shown in FIG. 1(A), and welding was performed. As a result, peeling tests to check the adhesion of welded areas showed that the defect rate was reduced from 0.3% of conventional flat flange welding to 0.03%, and the welding power was also reduced to 15 inches less than conventional flat flange welding. did it.

(G) Specific Example ■ In a test for manufacturing H-beam steel of the same size as above, the flange was bent at 170° at the center by the processing method of the present invention shown in FIG. 1(D), and the maximum bulge height was 0. 8■ Molding process, and furthermore,
The web end was widened to 3.4 m in accordance with the flange molding shape and welded.

As a result of 7, the peeling test defect rate was reduced by 0.01%, the welding power was further reduced by 12 cm compared to the specific example (I), and welding was possible with approximately % less power than the conventional method. Ta.

(a) Effect According to the method of the present invention, the processed and formed portion 11 of the flange material l
, 12.13, the high frequency current is concentrated on the area, so that area can be heated to a higher temperature than other areas.

The shape of the welded part is shown in Figure 3. Convex portion 1 of flange material 1
1 and the end-widening portion 21 of the web material 2 are smoothly joined, and the bead shape is also good.

(B) Effects According to the method of the present invention, welding defects can be significantly reduced, product yield can be significantly improved, welding power can be reduced, and manufacturing costs can be lowered. Furthermore, the rate of scale generation on the flange material was also significantly reduced. The shape of the bead was also very good, and no problems occurred during subsequent painting.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing the method of the present invention. FIG. 2 is an explanatory diagram showing a conventional method. FIG. 3 is a partial cross-sectional view of a weld formed bead according to the method of the present invention. FIG. 4 is a partial sectional view of a bead formed at a welded portion by a conventional method. 5 to 7 are front views of a flange processing roll for carrying out the method of the present invention. 1: Flange material 2: Wap material 11: Flat convex portion 12: Curved concave portion 13: Curved convex portion 14; Concave portions 21, 22: Widening portions 31, 32, 33, 34, 35, 36: Rolling roll patent applicant Sumitomo Metal Industry Co., Ltd. (5 people)

Claims (1)

[Claims] Forming a processing and forming part in the center part of the flange material, and forming the processing and forming part with a rolling roll to a thickness of 3 to 3 times the thickness of the flange material.
A high-frequency butt welding method comprising rolling with a reduction of 20% to form a bulging portion, and performing high-frequency welding by butting an end of the web material against the processed and formed portion.