JPS6240989A - Energy beam welding method - Google Patents

Abstract

PURPOSE:To reduce the meltdown and burn through at both end parts and to form a good joint by abutting the end face of a metallic plate each other, by placing a metallic material on both ends of the above of the butt line thereof and by applying energy beam on the metallic material and butt line part. CONSTITUTION:The end part of steel plate 1, 1' is sheared and subjected to butt clamp. The metallic materials of a metal foil, metal wire, metal powder paste, etc. are then placed on the abutted both ends and by using a metallic powder paste F a metallic layer can easily be formed in a gap (g) with its flowing approach in the abutted gap (g) from a nozzle. The butt part is subjected to a seam welding in succession by irradiating the energy beam on the metallic powder paste F and butt part. A laser beam, electron beam, TIG arc, gas arc, plasma arc, etc. may be used as for the energy beam.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to butt seam welding, and in particular to butt seam welding of ultra-thin steel plates.

[Conventional technology]

In a continuous processing line for thin steel plates, various welding methods are used to connect the ends of the preceding strip and the following strip for continuous threading. Currently, there is no satisfactory welding method due to problems and welding speed. However, regarding welding of thick plates, for example, welding journal 1959
As shown in the December issue, pages 1182-1191, the TJG arc welding method is mainly used.

If the plate thickness is about 0.35+am, it is possible to weld using the TTG arc welding method, but since the welding current is IOA and minimal current welding, the arc becomes unstable and the power supply characteristics greatly affect the welding process. As a result, bead formation becomes unstable, leading to welding defects.

These problems are exacerbated by the condition of the end faces of butted steel plates, so there is a method to improve the precision of end face processing and reduce the gap between both end faces, but especially for wide steel plates,
The equipment cost for this becomes extremely large.

In addition, this conventional method is applicable to 0.35+nm or less plate thickness.
When the thickness becomes 2 mm, defects described in -]2 are likely to be promoted.

Further, it is required to further reduce the welding current and stabilize the arc. Furthermore, it is necessary to further improve the processing accuracy of the butt ends and the accuracy of the steel plate clamping device.

[Problem that the invention seeks to solve]

As explained above, in the conventional TTG arc welding method,
When welding ultra-thin plates, there are problems in that the welding phenomenon is unstable, making it easy for weld to drip or hump, and extremely high precision is required for coil butt control and TTG torch seam tracing control.

In particular, it is a serious problem that welding at both ends of the weld line may drop or welding may occur due to insufficient molten metal.

Further, it is better to have as high a precision as possible in matching the coils, but in any case, mechanical operations such as shearing and clamping are involved, so it is unavoidable that a gap of I/100 mm will remain inside and outside. Molten steel melted by an arc heat source fills the gap between the end faces of the coil during welding, but as the thickness of the plate decreases, the gap to be filled becomes larger relative to the welding part. , there is insufficient melting, and there is a lack of molten metal at both ends of the weld line, resulting in unwelded areas or dropped weld spots a as shown in FIG.

It is an object of the present invention to solve these problems and to form a sound joint by minimizing weld drop or weld failure at both ends.

[Means for solving problems]

In the present invention, the end surfaces of the steel plates to be welded are butted against lf, metal materials such as metal foil, metal wire, metal powder paste, etc. are placed on both ends of the butt, and an energy beam is irradiated to the metal materials and the butt portion. At both ends, the abutting portions containing the metal material are melted, and the abutting gap is filled with the molten metal material.

When the metal material is metal foil or metal wire, it should be thick enough to sufficiently fill the butt gap by melting and not excessively increase the excess welding, and be butted at both ends of the butt wire. position exactly on the line. When making a metal powder paste, apply it to both ends of the butt line.

Since the metal powder paste has fluidity, it enters the butt gap and fills the gap by applying it. Therefore, it is effective to use metal powder paste for welding that sufficiently fills the gap and does not make the surplus of welding excessively large.In particular, it is effective to apply metal powder paste 1- and then apply the blade to the surface of the steel plate. to scrape off the metal powder paste on the surface, etc.
A suitable metal layer can be formed in the butt gap by a simple process.

The present invention will be described in detail below with reference to the drawings.

Figure 2a shows the steel plate to be welded 1. Indicates the comparison status of B.

A gap g is created between the steel plates 1 and 1'.

FIG. 2b shows the state in which the metal powder paste F is applied in the gap between the ends of the butt lines of the steel sheets 1 and 1' and in the vicinity of the ends 11.degree. 11' of the steel sheets according to the present invention.

The metal powder paste 1-F is supplied and applied so as to fill as much of the space g as possible. Further, the metal powder paste 1- overflowing on the surface of the steel plate is reduced as much as possible by scraping it off with a blade, and the excess buildup of the weld bead caused by welding is reduced.

FIG. 3 shows an example of energy beam welding according to one embodiment of the present invention. 1. IL indicates a steel plate. E I +
F2 + F3 indicates the steel plate butt part, E indicates the gap in the middle, F2 indicates the metal powder paste buried in one end,
F3 indicates a welded cross section.

N2 is a paste supply nozzle that supplies metal powder paste;
Denoted at 1 is a paste inlet, and at F2 is a paste outlet. These serve as a mechanism for applying the metal powder paste F into the gaps at both ends of the abutting portion of the steel plates.

N1 is a laser welding nozzle, r and B are laser beams from a laser oscillator, and [7B2 is a laser beam that irradiates the steel plate butt portion and the metal powder paste at both ends.

To carry out the present invention, first, the ends of the steel plates I, 1' to be butt welded are sheared using a shear.

Butt and clamp the ends. Next, as shown in Figure 3,
The metal powder paste F is supplied between the steel plates at both ends of the butt line by the paste supply nozzle N2, and the metal powder paste is press-fitted into the butt gap g as shown in FIG. 2b. Next, the metal powder paste on the surface of the steel plate is scraped off with a blade. At this time, the metal powder paste further enters the inside of the gap. Following this operation, laser beam 1. Irradiate B2 along the butt line. The beam diameter of the laser beam L B 2 is made large enough to melt the metal powder paste including the abutting ends of the steel plates.

In addition, the laser output is controlled by taking into account the steel plate thickness, welding speed, and beam diameter, and setting it within a range where melt drop does not occur.

As shown in FIG. 2b, the metal powder paste does not need to completely fill the gap between the butt steel plates, but only needs to be filled in an amount that allows both steel plates to be welded by melting the butt ends of the steel plates and melting the metal powder.

In addition, in the above explanation, the case where a laser beam is used as the energy beam was described, but the energy beam used in the present invention may be a laser,
Electron beam, TI'G arc.

Any type of arc, such as gas arc or plasma arc, can be used.

〔Example〕

Next, an example of the present invention is shown in which the metal powder is 20 to 40 μm.
The binder is a vinyl resin and a solvent (alane/xylene 1:1), and the metal powder, vinyl resin, and solvent are each 75% by weight by weight.
8% and 13% were made into a paste, the laser output was 0.5 kW, the beam diameter was 1 mm, and a thin steel plate with a thickness of 0.2 mm was welded. The butt gap between both ends was O.Imm, and the metal powder paste was applied to a range of 10 mm from the edge at each end.

In the conventional case, when the plate thickness is as described above and there is a gap of 0.1 mm, the molten material cannot completely fill the gap at both ends, and melting at the ends of about 2 to 5 mm causes droplets. According to this example, the drop in edge melting was less than 0.15 mm.

Furthermore, as a result of cutting out the joint obtained in the example described in - and repeatedly bending tests, it was found that the joint had better joint performance than conventional TTG welding or gas welding. .

〔Effect of the invention〕

As explained above, according to the present invention, the drop of edge melting becomes extremely small. In addition, even if the end butt gap is relatively large, the molten part can be completely buried, making it possible to reduce the machining accuracy of the end butt surfaces of the steel plates, and reduce the cost of incidental equipment such as steel plate cutting equipment and presser mechanisms. It is possible to reduce
Furthermore, the effects are great, such as the ability to automate welding.

[Brief explanation of drawings]

FIG. 1 is a plan view showing a welded part of an ultra-thin steel plate that has an unwelded part due to conventional welding. FIG. 2a is a cross-sectional view showing the butt gap between steel plates, and FIG. 2b is a cross-sectional view showing the butt gap between the ends of the weld line filled with metal powder paste according to the present invention. FIG. 3 is a sectional view showing one embodiment of the present invention. ], I': Steel plate t: Thickness F: Metal powder paste N1: Laser welding nozzle LB1. LR2: Laser beam N2: Paste supply mechanism El: Butt gap E2: Metal powder paste E3:
Weld cross section

Claims (2)

[Claims] (1) The end surfaces of the metal plates to be welded are butted against each other, metal materials are placed on the butt line and at both ends, and an energy beam is applied to these metal materials and the butt line between these metal materials. An energy beam welding method characterized by welding the butt parts using (2) The energy beam welding method according to claim (1), wherein the metal material is a metal powder paste in which a binder is mixed with metal powder.