JPH0852588A - Steel wire for gas shielded arc welding and its production - Google Patents

Abstract

PURPOSE:To improve feeding performance by forming a vertical groove of a specific depth in the longitudinal direction of a steel wire for gas shielded arc welding, thereby lowering the bending rigidity in the longitudinal direction of the steel wire and reducing a feeding resistance. CONSTITUTION:In the process of intermediate drawing, annealing, acid cleaning, copper plating and finish drawing on a hot-rolled steel, a vertical groove 2 in a U-shape, V-shape, etc., is imparted in the longitudinal direction to the steel wire 1 which is intermediately drawn by using a roller with a projection in the intermediate drawing process. The groove is further processed into a narrower vertical groove 2 in subsequent drawing with a die; and finally a vertical groove 2 is formed having a depth of 1/10 or more but 1/2 or less of the diameter of the steel wire in its longitudinal direction. In addition, as the shape of the roller with the projection, the A value (W/d), a ratio of the maximum width W over the height (d) of the projection of the U or V shape, is set 0.5 or more but 1.8 or less, and the vertical groove is thereby efficiently formed. Thus, the feeding performance is further improved by impregnating the vertical groove with a lubricant for example.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steel wire for gas shielded arc welding which is excellent in feedability and a method for manufacturing the same.

[0002]

2. Description of the Related Art In recent years, the automation and unmanned welding have progressed as seen in the examples of welding robots, and the steel wire used for this is often supplied from a pail pack. The steel wire wound in the pail pack weighs over 100 kg, and continuous welding for a long time is possible. However, since the steel wire is often wound around by winding it in the pail pack, and the distance from the pail pack to the welded part is often large, it is possible to reach a torch through a conduit cable having a length of 5 to 10 m on the way. Since the steel wire must pass through a curved path having different directions and radii, there is a problem that the resistance of the steel wire when passing through the conduit cable is large and the feedability of the steel wire is hindered.

In order to improve the feedability of the steel wire, studies have been made so far on the shape of the steel wire surface, coating of the steel wire surface, control of the amount of lubricating oil applied, and the like. For example, Japanese Patent Publication No. 63-21595 discloses a method of forming a plating crack as an oil pocket on the surface of a steel wire, and Japanese Patent Laid-Open No. 63-144893 discloses a method of coating a resin on the steel wire. There is. Also, various lubricants applied to the surface of the steel wire have been proposed such as Japanese Patent Publication No. 58-46398.

[0004]

The method for forming plating cracks and the method for coating with a resin both require special treatment during their production, and in any case, they are drawn out during finish drawing. There is work hardening due to the increase in the rigidity of the steel wire, making it difficult to flexibly bend the curved part of the conduit cable, which increases the feed resistance and completely solves the feed failure. It was difficult.

On the other hand, by reducing the wire diameter during annealing after intermediate wire drawing and reducing the area reduction rate during finish wire drawing, work hardening is suppressed to a certain extent and feedability is secured. It is also possible. However, this method has a problem that the productivity is poor, the cost is high, and the management in the manufacturing process is complicated.

[0006]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and provides a method for lowering the bending rigidity of a steel wire in the longitudinal direction in order to flexibly cope with the bending of a conduit cable. This is the result of various studies. That is, the present invention relates to a steel wire for gas shield arc welding, having a depth of 1/10 or more, 1/2 or less, preferably 1/4 or more, 1/2 or less of the diameter of the steel wire in the longitudinal direction of the steel wire. The present invention is a steel wire for gas shield arc welding excellent in feedability, characterized by having vertical grooves, and the present invention is an intermediate drawing of a hot rolled steel material, annealing, pickling, and copper plating. In the method for producing a steel wire for gas shield arc welding which further finish-draws, by using a roll having a convex portion at the time of intermediate drawing, 1/10 or more of the steel wire diameter in the longitudinal direction of the steel wire, 1 /
A method for producing a steel wire for gas shield arc welding, characterized in that a vertical groove having a depth of 2 or less, preferably 1/4 or more and 1/2 or less is provided, and a roll having a convex portion is
A value (W / W) represented by the ratio of the height d of the convex portion to the maximum width W of the convex portion
It is desirable that d) be 0.5 or more and 1.8 or less.

[0007]

[Function] The steel wire 1 for gas shielded arc welding is provided with 1/10 or more of the steel wire diameter in the longitudinal direction of the steel wire, 1 /
By reducing the bending rigidity of the steel wire in the longitudinal direction by providing the longitudinal groove 2 having a depth of 2 or less, the steel wire can flexibly correspond to the curved portion of the conduit cable and pass therethrough. As a result, the feed resistance is reduced and a steel wire having excellent feedability can be obtained.

The direction of the flutes must be given in the longitudinal direction of the steel wire. There is no effect even if applied in a direction perpendicular to the longitudinal direction of the steel wire, that is, in the radial direction of the steel wire, and there is a risk of disconnection. However, as shown in FIG. 1 (b), the effect of the present invention is not diminished even if the longitudinal grooves are provided in a spiral shape in a curved line in a sufficient length of the steel wire. Often becomes.

The depth of the flute is 1 with respect to the diameter of the steel wire.
If it is less than / 10, the effect of reducing feed resistance is not recognized, so
The depth of the vertical groove was set to 1/10 or more of the diameter of the steel wire. In particular, when the depth of the vertical groove is 1/4 or more, a remarkable effect is exhibited. Further, the depth of the vertical groove needs to be controlled to ½ or less in order to prevent a score line during manufacturing, particularly a score line when two or more vertical lines are formed.

The number of vertical grooves is not particularly limited, but is 1 to 3.
A book is enough. The width of the vertical groove is not particularly limited, but may be 3 to 20 μm. In the production of the steel wire of the present invention, it is necessary to mechanically make a depression in the steel wire, and as a method therefor, it is possible to process the roll into a convex shape in advance and transfer it to the steel wire. .

As a method for providing the vertical groove, a hot-rolled steel material is intermediately drawn, annealed, pickled, copper-plated, and further finish-drawn, which is a general method for producing a steel wire for gas shield arc welding. In the wire drawing step, by using rolls 3 and 4 having protrusions as shown in FIG. 2 in the intermediate wire drawing step, a U-shaped or V-shaped groove is formed in the longitudinal direction in the intermediate wire-drawn steel wire 1a. To form a narrow flute at the time of subsequent wire drawing with a die, and finally a flute having a depth of 1/10 or more and 1/2 or less of the steel wire diameter in the longitudinal direction of the steel wire 2 It is industrially effective to obtain a steel wire having

Further, as the shape of the roll having the convex portion,
By setting the A value (W / d) represented by the ratio of the height d of the U-shaped and V-shaped convex portions to the maximum width W of the convex portions to 0.5 or more and 1.8 or less, it is possible to efficiently obtain the flutes. . If the A value is less than 0.5, the width of the lower portion with respect to the height of the convex portion becomes too small and the strength is weak, so that it is likely to cause trouble during manufacturing.
Further, the groove depths of the obtained products have large variations.

On the other hand, when the A value exceeds 1.8, the groove depth decreases at a high speed equal to or higher than the decreasing speed of the steel wire diameter due to the wire drawing work, and disappears depending on the area reduction rate. Therefore, there is a limit to the area reduction rate after the grooves are formed by the rolls, and as a result, it becomes necessary to form the grooves by the rolls at a stage close to the product diameter, which lowers the productivity. The steel wire according to the present invention can be further improved in feedability or can be improved in arc stability by impregnating or including a known lubricant or arc stabilizer in the flutes.

[0014]

EXAMPLE Hot-rolled steel wire of alloy steel having composition shown in Table 1 7.0
mmφ was formed in the U-shaped and V-shaped grooves through the rolls shown in FIGS. 2 (a), (b), (c) and (d) during the wire drawing process. After that, a final product of 1.2 mmφ welding steel wire was obtained and feedability was evaluated. FIG. 3 shows the apparatus used for feeding evaluation. Feeding motor 13 when the welding steel wire wound around the bobbin 11 is fed at a feeding speed of 12.5 m / min through a conduit tube 12 having a length of 5 m and a loop 12a of 200φ is formed in the center thereof. The load current was measured with an ammeter 14 for 1 minute. 15 is a speedometer and 16 is a welding torch.

A value (W / d) of the convex portion applied to the roll,
Table 2 shows the ratio of the flute depth to the wire diameter and the load current value. The measurement results are shown in FIG.

[0016]

[Table 1]

[0017]

[Table 2]

When the depth of the flute becomes 1/10 or more of the diameter of the steel wire, the feed motor current decreases and the variation becomes small. Further, when the depth of the vertical groove is 1/4 or more, the feed motor load current further decreases. If the depth of the flute is less than 1/10 of the steel wire diameter, no improvement effect is observed. It should be noted that in the embodiment having a plurality of vertical grooves, there was a tendency that the variation in the load current was smaller than that in the embodiment in which a single vertical groove was formed.

[0019]

According to the present invention, the feedability can be improved by providing the steel wire with the vertical groove.

[Brief description of drawings]

FIG. 1 is an explanatory view of vertical grooves of a steel wire according to the present invention.

FIG. 2 is an explanatory diagram showing an example of the shape of a roll that imparts vertical grooves to a steel wire.

FIG. 3 is an explanatory diagram of a test device for a feedability of a steel wire.

FIG. 4 is a characteristic diagram showing a relationship between a vertical groove depth of a steel wire and a feed motor load current.

[Explanation of symbols]

 1 Steel Wire 2 Flute 3, 4 Roll with Convex 11 Bobbin 12 Conduit Tube 13 Feed Motor 14 Ammeter 15 Speedometer 16 Welding Torch d Flute Depth w Flute Width

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[Procedure amendment]

[Submission date] October 5, 1994

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0004

[Correction method] Change

[Correction content]

[0004]

The method for forming plating cracks and the method for coating with a resin both require special treatment in the production thereof, and in any case, work hardening by drawing work during finish wire drawing. There is
By increasing the rigidity of the steel wire, it became difficult to flexibly bend the curved portion of the conduit cable, and the feed resistance increased, making it difficult to completely resolve feed defects. .

[Procedure Amendment 2]

[Document name to be corrected] Drawing

[Name of item to be corrected] Fig. 4

[Correction method] Change

[Correction content]

[Figure 4]

Front page continuation (72) Inventor Akio Yamaura 1 Kawasaki-cho, Chuo-ku, Chiba-shi, Chiba Kawasaki Steel Co., Ltd.

Claims (3)

[Claims] 1. A steel wire for gas shield arc welding, wherein 1/10 of the diameter of the steel wire is measured in the longitudinal direction of the steel wire.
As described above, a steel wire for gas shield arc welding excellent in feedability, which has a vertical groove with a depth of 1/2 or less. 2. A method for producing a steel wire for gas shield arc welding, wherein a hot-rolled steel material is intermediately drawn, annealed, pickled, copper-plated, and finally drawn. 1/10 or more of the diameter of the steel wire in the longitudinal direction of the steel wire by drawing using a roll having
A method for producing a steel wire for gas shield arc welding, which comprises providing a vertical groove having a depth of ½ or less. 3. A roll having a convex portion is characterized in that an A value (W / d) represented by the ratio of the height d of the convex portion to the maximum width W of the convex portion is 0.5 or more and 1.8 or less. Item 2. A method for producing a steel wire for gas shield arc welding according to Item 2.