JPS6156791A - Feeding method filler wire in laser welder of metallic strip - Google Patents

Abstract

PURPOSE:To feed filler wires safely and continuously by controlling the clearance of butting parts of a metallic strip at less than the diameter of a filler wire and feeding the filler wire and the controlled crearance as a guide. CONSTITUTION:After a strip 1 is cramped by the upper and lower cramps, the strip is cut by the upper and lower shear and butted at less clearance than the diameter of a filler wire 9. After that, a lazer torch is run along the weld line and the beam is emitted to the butted part. The filler wire 9 is fed from the opposite direction of welding by following the weld line from a filler wire supply motor 10. In this case, a tip of the wire 9 from a guide tube 14 is fed to the weld line at the specified angle by taking the clearance of butted parts as a wire guide. Therefore, filler wires are welded continuously without wire bending and well penetrated wires and the high quality of weld can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION <Object of the invention> Industrial field of application The present invention relates to a method for supplying filler wire in laser welding of metal strips, and in particular, to a method for supplying filler wire in laser welding of metal strips, and in particular, to a method for supplying filler wire in laser welding of metal strips. The present invention relates to a method for stably supplying filler wire when connecting by laser welding.

2. Description of the Related Art Recently, in various manufacturing and processing lines for metal strips, butt welding of the metal strips using a laser has been carried out at the input side of the line in order to continuously supply the metal strips to the line.

In this laser welding, especially high silicon steel (31≧0
．． 8%), and high carbon steel (G≧0.3%), it is known that welding while supplying filler wire to the butt part of fully bent strips increases the welding strength by 1f (Patent ya57-1057@ ).

However, it has been extremely difficult to blend this filler wire into the slip (melt uniformly and appropriately with the base material over the entire width of the slip) due to the following reasons (1), (2), and (3).

(1) The butt gap between slip 1 and slip is 0.05 to 2.
Very narrow at 0111m, filler Y A7 100r
JU is difficult; (2) the focal diameter of the laser beam is 0.1 to 0.8n+mφ;
(3) The filler wire is wound on a reel. Because the filler wire is unwound and fed to the butt part, the winding curl is perfect. It is difficult to remove the filler wire, and position control is difficult.Furthermore, the curl at the opening changes as it is unwound.For these reasons, it is not possible to stably supply the filler wire, and the Fc Or, even if it melts, it does not enter the gap between the butt parts, resulting in a welding failure.

For example, as shown in FIG. 3(a), in the gap a between the leading strip 1 and the trailing strip 1', the laser beam focused by the condenser lens 13 and the strip surface intersect. In comparison, if the filler wire 9 is supplied at a high position, or even if the filler wire is supplied to the above-mentioned intersection position as shown in FIG. The welding line 1a is as shown in FIG. 4, for example.

As mentioned above, conventionally, in laser welding using filler wire, the filler wire was stably attached to the metal
It was difficult to supply it to the butt part of the lips, and it was not possible to obtain the desired welding quality.

Problems to be Solved by the Invention The present invention was developed in view of the above-mentioned problems.
Specifically, the purpose is to solve the problem that filler wire cannot be stably supplied to the abutting portions of strips during laser welding of gold-skinned slips.

<Structure of the Invention> Means for Solving the Problems and Their Effects First, the present invention requires a guide at the tip of the filler wire to stably supply the filler wire, and a metal guide is used as the mouth guide. Each end face of the abutted portion of the strips itself is suitable, and the main idea is to take advantage of this fact to supply the filler wire from the direction opposite to the welding direction for laser welding.

At this time, the gap between the abutting portions of the metal strips is important, and this gap is adjusted to be less than the diameter of the filler wire, and the filler wire is supplied using the thus adjusted gap as a guide.

That is, when supplying the filler wire as described above,
The quality of wire melt forming is determined by the relationship between the gap (a) at the abutting part and the diameter (b) of the wire, that is, the relationship between l]/a, and the relationship between l]/a and melt forming. When the relationship between the quality and the quality of the intrusion was determined, the hitting relationship shown in FIG. 10 was found to be 13. In Fig. 10, the weld bead can be tested over the entire length, and the part (a) where the filler wire has penetrated sufficiently and the weld quality is good (b) is the part J5, which can be improved by grinding or other maintenance, and the part J5 (c). The welding quality was divided into areas that could not be salvaged by maintenance due to poor welding quality, and the quality of penetration was shown by the percentage of each of these areas. From FIG. 10, when b/a is 1 or more, that is, when the wire diameter (b) is larger than the gap (a), the weld build has sufficient penetration over the entire length,
It was found that the welding quality was good.

Furthermore, when supplying the filler wire as described above, it is desirable that the filler wire be supplied at an appropriate angle and at an appropriate supply position.

The present inventors investigated the conditions for further stabilizing laser welding when supplying the filler wire as described above, and found the following.

(1) The feed angle of the filler wire is within the optimum range. If the feed angle θ is too large, the tip of the filler wire 9 will bend as shown in FIG. 5 (4) when the filler wire 9 hits the metal strip 1. , cannot be supplied to the butt part.

(2) The length of the guide by the fully bent strip abutting part is within the optimum range. When this guide becomes too long, the effect of curling of the filler wire begins to appear as shown in FIG.

(3) If the position of the tip of the guide tube 14 of the filler wire supply device is within the proper range (IIl), the filler wire 9 will be unwound as shown in FIG. 7 as in (2). will be affected.

In addition, in FIG. 5 and FIG. 6, numeral 1 is a gold mud strip, 9 is a filler wire, 14 is a guide tube,
θ is the feeding angle, C is the distance from the point where the filler wire touches the strip surface to the intersection of the laser beam optical axis and the strip surface, and d is the distance from the tip of the guide to the intersection between the laser beam optical axis and the strip surface. distance to the intersection of , the arrow indicates the welding direction.

In short, the above conditions indicate that when supplying filler wire from the direction opposite to the welding direction during laser welding, the factors that affect the quality of wire penetration are mainly the butt I.
! ! The relationship between the diameter of the filler wire and the gap is
In addition, the supply angle of the filler wire and the position at which the filler wire is supplied are also shown.

Therefore, after thinking about the influence of these factors on the quality of wire penetration, we found that Figures 11, 12, and 13.
The relationship shown in the figure is 1q. In these, the quality of wire penetration is shown in the same way as in FIG. 10, and θ, C, and d are shown in the same way as above.

In other words, when considered in conjunction with what is shown in FIG. 10, the ratio b/
When a is 1 or more, filler wire supply angle θ
is within 35°, filler wire supply position ff0.5
Range of mm to 5 mm, guide tube tip position d is 20
It is preferable to set it within n+n+, and under this condition,
A bead with good weld quality can be obtained over the entire length in the weld line width direction.

Example Next, an example will be described.

First, FIGS. 1 and 2 are side views of an example of an apparatus for carrying out the method of the present invention, in which FIG. 1 shows the state in which the ends of both leading and trailing strips are cut, and FIG. 2 shows the state in which butt welding is performed. shows. Therefore, the laser beam
When welding the ends of the strip 1.1-, as shown in Fig. 1, the strip 1.1- is clamped with the upper and lower clamps 4.5, then sheared with the upper and lower shears 17-2.3, and the cut surface is separated by a certain gap (filler). smaller than the diameter of wire 9).

After that, as shown in Figure 2, the laser torch is run along the welding line and the beam is irradiated to the abutting part to weld the seal (6 is the laser torch running frame, 7 is the laser condensing lens header, and 8 is the laser beam) 11 is a shark lamp cylinder, 12 is a back bar, and 14 is a laser condensing lens). The filler wire 9 is connected to a filler wire supply motor 10 as shown in the figure.
The filler wire 9 is supplied from the opposite direction to the welding direction in conjunction with the welding line, but at this time, the tip 9 d of the filler wire 9 coming out of the guide tube 14 uses the gap at the abutment part as a wire A7 guide, and ( Therefore, the wire center is located within the gap) and is fed to the welding line within a feed angle θ of 356°.

That is, as shown in FIG. 8, an angle θ of 35° or less, not shown in FIG.
Feed within 2 On++n of ff0.5mm to 5+nm%d. Therefore, welding is performed continuously without being affected by the winding curl of the wire A7, and the wire melts into the gap at the butt part well, and the base metal melt penetrates well to obtain a good welding quality. Secured.

<Effects of the Invention> As explained in detail above, the method of the present invention adjusts the abutment gap between the metal strips to be smaller than the diameter of the filler wire, and guides the end of the filler wire by the end face of the abutment portion to weld in the opposite direction to the welding direction. This is a method of supplying from

Since the end of the filler wire is properly guided and fed in this way, the filler wire can be fed stably and continuously even if the curling @ lf remains, and in addition, the gap and n of the filler wire 1 diameter is maintained in an appropriate relationship, sufficient weld penetration into the base metal is obtained, and a good welded joint 1f (q) is obtained.

[Brief explanation of drawings]

1 and 2 are side views of an example of an apparatus for carrying out the method of the present invention, FIGS. 3(a) and 3(b) are explanatory views of a conventional filler wire supply mode, and FIG. FIGS. 5, 6, and 7 are explanatory diagrams of the welding line in the conventional example. FIGS. 5, 6, and 7 are explanatory diagrams in the case of filler wire supply failure in the conventional example. FIGS. 8 and 9 are the filler wire in the method of the present invention. 10 and 11 are explanatory diagrams showing the relationship between the supply positions of
12 and 13 are graphs showing the relationship between the supply conditions of filler 1 tin and welding quality in the method of the present invention. Code 1... Leading strip 1 -... Trailing strip 2... Upper shear blade 3... Lower shear blade 4.5... Shark lamp 6... Laser torch running frame 7...
・Laser Toko lens header) 18... Laser Toko lens header lifting motor 9... Filler wire 10... Filler wire supply motor 11...
... Shark lamp cylinder 12 ... Back bar 13 ... Laser condensing lens 14 ... Filler wire guide tube Patent applicant Kawasaki Tetsu Co., Ltd. person
Patent Attorney: Yoshikatsu Matsushita, Attorney-at-Law
01 Fumi Shima 1st Fg! J

Claims (1)

[Claims] When butt welding metal strips using a filler wire with a laser beam, adjust the butt gap between these metal strips to be less than or equal to the diameter of the filler wire, and use the end face of this butt portion as a guide to weld the filler wire in the welding direction. A method for feeding filler wire in laser welding of metal strips, characterized in that filler wire is fed from opposite directions.