JPH02211979A - Device for joining band-shaped metallic sheets - Google Patents

Abstract

PURPOSE:To prevent the occurrence of defective welding, porosity and gas scum by providing a tapered electrode on the welding torch tip of welding equipment and forming the specified arc generating surface on the electrode tip. CONSTITUTION:The band-shaped metallic sheet 10 and 22 ends are subjected to TIG welding and joining by the welding equipment 24 and the welded and joined part is rolled by a rolling device to join the band-shaped metallic sheets 10 and 20 together. The tapered electrode 30A is then provided on the welding torch 30 tip of the welding equipment 24. The arc generating surface (lower end face) B formed of the circular flat surface having >=0.3mm diameter is formed on the tip of the electrode 30A. By this method, even if the arc length is changed suddenly on the welding starting end or the welding finishing end of the welding and joining part, an arc is prevented from becoming unstable.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a joining device for band-shaped metal plates, and particularly to a joining device for band-shaped metal plates for joining ends of flexible band-shaped metal plates. Regarding.

[Conventional technology]

The band-shaped gold rR temporary joining method includes a method of overlapping and joining the band-shaped metal plates or a method of butting and joining the band-shaped metal plates. FIG. 4(a) is a perspective view showing a conventional overlapping joining method. As shown in FIG. 4(a), a band-shaped metal plate 7
0 and the end of the band-shaped metal plate 72 are overlapped,
The joining surface 73 is adhered with double-sided adhesive tape or fused by ultrasonic waves (FIGS. 4 and 6 of Japanese Patent Application Laid-Open No. 59-24526).

Further, FIG. 4(b) is a perspective view showing a conventional butt joining method of band-shaped metal plates. As shown in Figure 4(b),
The ends of the band-shaped metal plates TO, 72 are butted against each other, and the butt-jointed portion 75 is joined with one-sided adhesive tape 76, 76 (FIG. 2 of JP-A-59-24526).

However, in the conventional method of joining band-shaped metal plates as shown in FIG. 4(a), there is a step at the joining part, so it is not possible to make smooth contact with a pass roller or the like. Further, in the photosensitive layer coating process in the manufacture of lithographic printing plates, the coating device must be evacuated to prevent damage when the joint portion of the band-shaped metal plate passes through. Further, even when there is no need to retreat the coating device, the bonding surface 73 adversely affects the coating state and causes quality defects.

In addition to this problem, since the joint surface 73 is often not bonded over the entire surface, the joint surface 73 may be bonded while the strip is being transported.
3 may be turned over. In addition, if there is a surface treatment process for the strip metal plate using a treatment liquid, when the strip metal plate passes through the treatment liquid, foreign matter such as the treatment liquid may enter the gap between the joint surfaces 73. This may cause quality defects in subsequent processes.

Furthermore, in the joining method by butting shown in FIG. 4(b), since the joining is performed using the one-sided adhesive tape 76, 76, a difference in thickness occurs at the joining portion due to the tape 76, 76. This level difference causes a problem similar to the problem in the overlapping joining method shown in FIG. 4(a). In particular, in the case of this method, the tape 76, 76 at the abutting section is damaged by the edge of the strip at the abutting section while being conveyed through the process by a pass roller, etc., which weakens the strength and makes it easy to cut. There is a point. Further, such a bonded band-shaped metal plate is subjected to bending stress when passing through the pass roller, and this bending stress tends to cause breakage at the bonded portion. This phenomenon is particularly noticeable when the strips are thin, such as 0.1 mm to 0.2 mm, or when there is a large difference in thickness between the two strips to be joined.

In order to solve these problems, we have developed a joining method in which metal strips are welded to each other and the welded joint is rolled to eliminate the difference in level.Also, we have developed a joining method that reduces the stress concentration in the heat-affected zone that occurs at the joint due to welding. A joining method that performs processing is disclosed.

Automatic arc welding is generally applied to this method, and fifth
As shown in the figure, the electrode 8G and the strip metal plate 10.22 are often ignited (arc is generated) in a non-contact state. That is,
He in the welding torch 84.

A mixed gas such as Ar is flowed in, and this mixed gas is blown out downward as a shielding gas from the opening 85A of the torch cup 85, and an arc is generated by the arc voltage between the electrode 86 and the back par 87. Next, welding torch 84
along the belt-shaped metal plate 10°220 to be joined (5th
(in the direction of the arrow in the figure) and move the band-shaped metal plate 10.22.
Weld and join. In this case, the electrode 86 and the strip metal plate 1O
Since the arc is generated in a non-contact state with the electrode 86, the tip of the electrode 86 is formed into a sharp edge, as shown in FIG. 5, to facilitate the generation of the arc.

[Problem that the invention aims to solve]

However, if the tip of the electrode 86 is formed into a sharp point, as shown in FIG. This causes the arc to become unstable. Therefore,
The belt-shaped metal plate is not sufficiently melted and sufficient back wave welding is not possible, resulting in poor fusion at the weld joint at the welding start end, or conversely, excessive arc heat is applied immediately after welding starts, causing the melt to fall off. There is a problem that holes may occur.

Furthermore, since the arc length rapidly increases to L' at the end of welding, there is a problem that the arc becomes unstable and welding defects and holes occur.

The present invention has been made in view of the above circumstances, and proposes a joining device for band-shaped metal plates that does not cause melting defects or holes at the welding start end and welding end of the weld joint between band-shaped metal plates. The purpose is to

[Means for solving problems]

In order to achieve the above-mentioned object, the present invention provides a welding device for joining band-shaped metal plates, in which the ends of band-shaped metal plates are TIG-welded together using a welding device, and the welded joint is rolled by a rolling device. The present invention is characterized in that a tapered electrode is provided at the tip of the torch, and an arc generating surface consisting of a circular flat surface with a diameter of 0.3 mm or more is formed at the tip of the electrode.

[Function] According to the present invention, a plane with a diameter of 0°3 or more is formed on the electrode of the welding torch, and an arc is generated from this plane, so even if the arc length suddenly changes at the welding start end or welding end end, The arc does not become unstable. Therefore, since the welded joints of the band-shaped metal plates can be sufficiently welded, it is possible to prevent poor melting, holes, etc. from occurring at the welded joints of the band-shaped metal plates.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a joining apparatus for band-shaped metal plates according to the present invention will be described in detail below with reference to the accompanying drawings.

As shown in FIG. 1, a strip-shaped metal plate 10 of A1 alloy is unwound from a roll 12, transferred to a pass roller 14, and conveyed to a joining device 16. Bricut device 18 of joining device 16
is composed of two sets of cutter blades 20.20. The leading end portion 10A of the band-shaped metal plate 10 is cut by the bricutting device 18, and the rear end portion 22 of the band-shaped metal plate 22 of A1 alloy is cut.
It is formed so that it can be accurately matched with A or overlapped by a minute amount.

A welding section [t24 is provided after the bricutting device 18, and the welding device 24 includes a clamp 26, 28 and a welding torch 30. The clamp 26 holds the tip end 10A of the band-shaped metal plate 10, and the clamp 28 holds the rear end 822A of the band-shaped metal plate 22. Therefore, the leading end 1i' 310A and the rear end 22A are butted against each other, as shown in FIG. 2, and the abutted portion is welded by high-frequency pulse arc welding. That is, the welding torch 30 is
The belt-like metal plate ends 10A and 228 are joined and welded by moving from position A to position 8 (in the direction of arrow C) of the abutting portion shown in the figure.

In the case of this embodiment, the welding torch 30 moves at a speed of 6ff+/min along the abutting portion of the band-shaped metal plates, and the welding current supplies enough heat to melt the tip N51OA and the rear end 22A. It is set up so that it can be done.

3(a) and 3(b) show a tungsten electrode 30A provided on the welding torch 30. As shown in FIG. 3(a), the tungsten electrode 3GA is formed into a substantially cylindrical shape with a diameter y as a whole, and from point A to point B on the lower end surface, the tungsten electrode 3GA is formed so as to gradually decrease from the diameter y to the diameter X. End surface B is formed into a flat surface. In addition, θ shown in East Figure 3 is 60 at the tip angle.
degree or less, preferably 45 to 20 degrees.

When joining band-shaped metal plates to each other by welding, the tungsten electrode 30A is separated from the band-shaped metal plates to generate an arc, and after the arc is generated, the tungsten electrode 30A is moved above the band-shaped metal plates to weld and join the band-shaped metal plates. In this case, as shown in FIG. 3(a), the tungsten electrode is connected to the strip metal plate 1.
When reaching above the welding start end of 0.12, the arc length rapidly decreases from the edge to L', but since the entire outer periphery of the flat surface B of the tungsten electrode 30A becomes the arc generation boundary, the arc is unlikely to become unstable. . Therefore, welding defects, holes, etc. do not occur between the ends of the band-shaped metal plates 10.22 that are welded together. Furthermore, when the tungsten electrode leaves the welding end, the arc length rapidly increases to L', but as described above, the arc is less likely to become unstable, so welding defects and holes do not occur.

A rolling device 32 is provided downstream of the welding device 24, and the rolling rollers 34 of the rolling device 32 are arranged at the end portions 10A and 2 of the strip metal plate.
2. Perform rolling of the welded joints. By such rolling treatment, the step formed in the welded joint is pressed and compressed. This rolling treatment increases the bonding strength. This is because the tensile strength reduced by welding is recovered by work hardening through rolling treatment, and at the same time, the material is processed into a shape that is less likely to cause stress concentration.

In the embodiment described above, the band-shaped metal plate 10 and the band-shaped metal plate 22 are butted against each other, but the present invention is not limited to this, and they may be slightly overlapped. Note that in the case where the strip metal plate 10 and the strip metal plate 22 are bonded together in a minute overlap, a rolling process is particularly required.

Next, welded joints joined using the belt-shaped metal plate joining apparatus according to the present invention (with a flat tungsten electrode having a diameter of 0.3 mm or more at the tip) and welded joints joined using a sharpened electrode. We will explain the results of a comparative test with

The test samples kl~N11L30 had a thickness of 0. lO crucian carp, A1 alloy strip metal plates with a width of 915 m + a 1 am
Overlap and weld together at a welding speed of 6ffl/min.
The welded part is rolled under the same conditions after welding.

For samples Nα1 to Nα10, the tip angle of the tungsten electrode was 3
It is a band-shaped metal plate that has been ground to 0° and then joined with an electrode that has a flat surface with a diameter of 0.6 ms at its lower end.

Sample kit ~ 20 was ground to a 30° tip angle and then joined with an electrode that had a flat surface with a diameter of 0.3 mti on the lower end.
It is a strip-shaped metal plate.

Samples Nα21 to Nα30 are band-shaped metal plates joined by electrodes whose tip angles are polished to 30°.

These samples Nα1 to N1130 were welded together and their appearance before rolling was comparatively evaluated. As for the evaluation items, a comparison was made between the range from the welding start end to 10 fins and the range from the welding end to 10+n in terms of occurrence of soot-like stains, occurrence of defective melting, and occurrence of holes. The comparison method was to evaluate the occurrence status using the incidence rate. The results are shown in Table 1. 271 in the table
0 indicates that 2 out of 10 samples had soot-like stains, poor melting, holes, etc.

Table 1 As is clear from Table 1, samples 1 to 101lh11 were welded and joined using the belt-shaped metal plate joining apparatus according to the present invention.
~20 is the incidence of defective melting for all samples Na21~301.4 welded and joined using conventional sharp-shaped electrodes;
It can be seen that the rate of occurrence of holes becomes smaller. In addition, although it is not a defect that affects the joint strength like poor melting or holes, in order to eliminate soot-like contamination and obtain a glossy joint, the diameter of the flat surface of the lower end of the tungsten electrode must be adjusted. φ
It can also be seen that the φ0.6-sized one is better than the 0°3-sized one.

In addition, the appearance of all the samples used in the test was observed after rolling, and it was found that the defects in melting and holes in the samples with defects in melting and holes were not improved after rolling.

Although high-frequency pulsed arc welding has been described in the above embodiment, the present invention is not limited to this, and similar effects can be obtained with other TIG welding methods.

〔Effect of the invention〕

As explained above, according to the belt-shaped metal plate joining apparatus according to the present invention, the electrode of the welding torch has a diameter of 0 for arc generation.
．． Since a plane of three dragons or more is formed, the arc will not become unstable even if the arc length suddenly changes at the welding start end or welding end end of the weld joint. Therefore, it is possible to prevent poor melting, holes, and soot stains from occurring.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of a joining device for band-shaped metal plates according to the present invention;
FIG. 2 shows a belt-shaped metal plate joining apparatus according to the present invention.
FIG. 3(a) is a plan view showing the state in which the II plate is welded, FIG. Figure 3 (a)
Figures 4(a) and (b) are perspective views of the joints of conventional strip-shaped metal plates, and Figure 5 shows the positional relationship between the electrodes of the conventional welding device and the strip-shaped metal plates. FIG. 10.22... Band-shaped metal plate, IOA, 22A...
Tip part, 16... Joining device, 18... Pre-cutting device, 24... Welding device, 30.84...
Welding torch, 30A, 86...Tungsten electrode, B...Lower end surface.

Claims (1)

[Claims] (1) In a band-shaped metal plate joining device that uses a welding device to TIG weld the ends of the band-shaped metal plates to each other and rolls the welded joint in a rolling device, a tapered electrode is attached to the tip of the welding torch of the welding device. 1. An apparatus for joining band-shaped metal plates, characterized in that an arc generating surface consisting of a circular flat surface with a diameter of 0.3 mm or more is formed at the tip of the electrode.