JPH06285678A - Gas shielded arc welding wire - Google Patents

Abstract

(57) [Summary] [Purpose] In the case of high-speed wire drawing during wire production, no wire breakage or surface damage occurs, and when using a soft long conduit cable and welding under high current conditions. Another object is to provide a welding wire having good feedability. [Structure] A lubricant comprising 1 to 2 kinds of vegetable oil and animal oil as a base oil and 3 to 10% of graphite having a particle diameter of 10 μm or less and 10 to 30% of molybdenum disulfide having a particle diameter of 3 μm or less on a wire surface. 0.3 ~ 10kg
It is characterized in that 1.8 g was applied.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wire for gas shielded arc welding (hereinafter referred to as "welding wire") which has good wire drawability during welding and good feedability during welding.

[0002]

2. Description of the Related Art Welding wires include solid wires and flux-cored wires, of which flux-cored wires can be manufactured by plating or wet drawing without a seam (seam). There are a wire and a flux-cored wire having a seam portion, which is manufactured by bending a strip steel, filling and wrapping the flux in the inside, and dry-drawing.

These welding wires are used for welding automation,
With the progress of high efficiency, it tends to be used more often, but recently, from the viewpoint of efficiency, regardless of automatic or semi-automatic welding,
High current density welding conditions are being adopted, which inevitably results in higher wire feed rates. In addition, depending on the target structure, welding is often performed in the squeezed part, and from the viewpoint of ease of use at those locations, the conduit cable from the feed roller of the wire feeder of the welding machine to the welding torch is used. Bends to make it easier to use, so it tends to be soft and long. When the welding wire is supplied at such a high speed and the conduit cable is long and easy to bend, the friction resistance when the wire passes through the conduit tube inside the conduit cable increases. However, there is a problem that the wire feeding is hindered during welding, the arc becomes unstable, and welding cannot be performed.

For this reason, welding wires have hitherto been
Various measures have been taken to improve the wire feedability, but none are sufficient, and welding workers are often forced to interrupt welding under severe conditions, such as replacing a rubbed conduit tube. , I'm having a hard time responding.
Further, when the wire for welding is manufactured, if the wire is drawn at a high speed in order to improve the efficiency, the slipperiness is deteriorated and the wire is broken, or the surface of the wire is scratched, which causes a problem in the wire drawability. To solve these problems of the feeding and drawing properties of the welding wire, a method of applying a lubricant to the surface of the wire as disclosed in Japanese Patent Publication No. 50-3256 has been disclosed in Japanese Patent Laid-Open No. 58-58.
-46398, higher fatty acids and alkali metal salts of higher fatty acids are drawn with a lubricant diluted with a volatile solvent,
A method for adhering an appropriate amount on the wire surface, or JP-A-58.
Various methods have been proposed, such as a method of applying a mixture of solid lubricants such as graphite, molybdenum disulfide and glass powder to the wire surface, which is described in Japanese Patent No. 184095.

[0005]

However, even in these methods, the above-mentioned flexible and long conduit cable is used, and it is used under a high current condition, or is drawn at a high speed during manufacturing. Under the conditions, it is still insufficient at present. Therefore, the present invention is free from disconnection and surface scratches even during high-speed wire drawing, and uses a soft and long conduit cable, and has good feedability even when welded under high current conditions. It is intended to provide a welding wire.

[0006]

DISCLOSURE OF THE INVENTION As a result of various studies on the lubricant used for wet drawing and the lubricant applied to the wire surface, the inventors have found that animal and vegetable oils as base oils and fine graphite and Wire drawing with a lubricant in which an appropriate amount of molybdenum disulfide is mixed and suspended, and by applying an appropriate amount of the lubricant on the wire surface, there is no trouble during high speed wire drawing,
It was found that even during welding, wire feedability under harsh conduit cables and high current conditions was extremely good. That is, the gist of the present invention is to use one or two kinds of vegetable oil and animal oil as a base oil,
Graphite with a particle size of 10 μm or less 3-10%, particle size 3 μ
A lubricant consisting of 10 to 30% of molybdenum disulfide having a size of m or less is applied to the wire surface in an amount of 0.3 to 1.8 per 10 kg of the wire.
The wire for gas shield arc welding is characterized by being applied with g.

[0007]

The welding wire of the present invention is characterized in that it is drawn with a lubricant prepared by mixing and suspending fine-grained graphite and molybdenum disulfide using vegetable oil and animal oil as a base oil, and applied in an appropriate amount. Palm oil, rapeseed oil, coconut oil, olive oil, etc. are used as the vegetable oil of the base oil, and lard, sheep oil, liver oil, etc. are used as the animal oil. These can be used alone or as a mixture, and basically, the sliding resistance at the time of wire drawing and the frictional resistance in the conduit tube of the wire at the time of welding are reduced to reduce the feeding resistance. By mixing and suspending graphite and molybdenum disulfide in the base oil, the high-speed drawability during wire production is improved, and a soft and long conduit cable is used during welding, and it is welded under high current conditions. In this case, the wire feedability in the case of

These effects can be achieved by the coexistence effect and the synergistic effect of the base oil, graphite and molybdenum disulfide. The reasons for limiting each of them will be described below. First, the particle size of graphite mixed and suspended in the base oil needs to be 10 μm or less. If the particle size exceeds 10 μm, it becomes difficult to mix and suspend in the base oil, and graphite is not uniformly brought to the wire surface at the time of wire drawing, and as a result, it is not evenly applied to the wire surface at the end of wire drawing. Sometimes wire breaks and surface scratches occur. In addition, the feedability during welding is also poor. The amount of graphite added to the base oil is 3
Must be -10%. If the amount of graphite is less than 3%, the amount brought in from the lubricant during wire drawing is small and the amount applied to the wire surface is small, so that wire breakage and surface scratches occur during wire drawing. In addition, the feedability during welding is also poor. If it exceeds 10%, both wire drawability and feedability are improved, but the amount of spatter generated during welding increases.

The particle size of molybdenum disulfide mixed and suspended in the base oil must be 3 μm or less. When the particle size exceeds 3 μm, molybdenum disulfide is not uniformly brought to the wire surface at the time of wire drawing and is not evenly applied to the wire surface at the end of wire drawing, resulting in surface scratches during wire drawing. In addition, the feedability during welding is also poor. The addition amount to molybdenum disulfide base oil needs to be 10 to 30%. If it is less than 10%, it will not be uniformly brought onto the wire surface at the time of wire drawing, and it will not be evenly applied to the wire surface at the end of wire drawing, causing wire breakage and surface scratches during wire drawing. Also, the feedability during welding becomes poor. If it exceeds 30%, it cannot be mixed and suspended in the base oil.

Next, the amount of lubricant applied to the welding wire of the present invention must be 0.3 to 1.8 g per 10 kg of the wire. If it is 0.3 g or less, the wire feedability during welding becomes poor. If the amount exceeds 1.8 g, good wire feedability can be obtained, but due to the hydrogen source contained in the base oil,
Since the hydrogen content in the weld metal increases, harmful defects such as broholes and hydrogen cracks easily occur, which is not preferable. The wire drawing with the lubricant used in the present invention is
At least the final skin pass wire drawing may be performed, but for example, it is preferable to use all of them for wire drawing from the wire diameter after plating to the skin path of the product diameter because high speed wire drawing is possible. The amount of lubricant applied to the surface of the welding wire is
It is controlled by the diameter reduction ratio at the final skin pass wire drawing.
That is, when the diameter reduction ratio in the final skin pass is large, the application amount is small, and conversely, when the diameter reduction ratio is small, the application amount is large.

[0011]

The present invention will be described in more detail with reference to the following examples. First, as shown in Table 1, various mixing amounts of base oil, graphite and molybdenum disulfide were mixed and suspended to prepare trial lubricants. Solid wire of YGW11 and JIS Z3 specified in JIS Z3312
A YFW24 seamless flux-cored wire (flux filling rate 14%) specified in 313 is 2.6 mm.
The lubricant drawn in Table 1 was placed in a die box, and wet drawn using a die of 8 to 12 to a product diameter of 1.2 mm. The drawing speed was 1000 m / min at the final skin pass exit. Table 1
The amount of lubricant applied to the surface of the wire shown in (4) was controlled by changing the diameter reduction ratio in the final skin pass.

[0012]

[Table 1]

The wire feedability was examined using the apparatus shown in FIG. That is, the diameter of 200
The test wire pulled out from the spool 2 was fed to a 6 m conduit cable 1 provided with a loop 2 rotation of mm by a feed motor 3 and fed to a torch 4. At that time,
The welding conditions are as follows. Welding current: 340A Arc Voltage: 33～36V welding speed: 35 cm / min shield gas: CO ₂ 20 liters / min Welding method: steels SM490B, thickness 20 mm,
With a gap of 16 mm, a groove angle of 20 °, and a groove with a backing, a welding length of 750 mm was used for multi-layer welding. The wire feedability was examined by measuring the armature current of the feed motor 3 and observing the arc state. The feedability becomes defective when the armature current exceeds 3.5A. After the completion of welding, an X-ray transmission test was carried out on a test example in which there were no problems in drawability and feedability. The results are shown in Table 2.

[0014]

[Table 2]

In Tables 1 and 2, Test Examples 1 to 8 are welding wire examples of the present invention, and Test Examples 9 to 16 are comparative examples. Test Examples 1 to 8 satisfying all the constituent requirements of the present invention,
In all cases, there was no disconnection or surface damage during wire drawing, the armature current of the feed motor was low even during welding, the arc state was good, and the weld metal was defect-free, which was a very satisfactory result. In Comparative Example 9, in Test Example 9, the particle size of graphite in the lubricant was large, and therefore wire drawing was interrupted, and the armature current of the feed motor during welding was high, and the arc was also unstable. Test example 1
In No. 0, the amount of graphite in the lubricant was large, so the wire drawability and feedability were good, but the amount of spatter generated was large. In Test Example 11, since the amount of graphite in the lubricant was small, some surface scratches occurred during wire drawing, the armature current during welding was high, and the arc was unstable.

In Test Example 12, since the molybdenum disulfide particle size in the lubricant was large, some surface scratches occurred during wire drawing. Also,
The armature current of the feed motor during welding was high and the arc was unstable. In Test Example 13, since the amount of molybdenum disulfide in the lubricant was large, it could not be mixed and suspended in the base oil of the lubricant. Therefore, wire drawing and welding were both stopped. Test example 1
In No. 4, since the amount of molybdenum disulfide in the lubricant was small, wire drawing was interrupted, and the armature current of the feed motor during welding was high and the arc was unstable. In Test Example 15, both the wire drawability and the feedability were good, but since the amount of lubricant applied to the wire surface was large, brohol occurred. In Test Example 16, the wire drawability was good, but since the amount of lubricant applied to the wire surface was small, the armature current of the feed motor during welding was high and the arc was unstable.

[0017]

As described above in detail, according to the gas shielded arc welding wire of the present invention, no wire breakage or surface damage is caused even under the high speed wire drawing condition during manufacturing, and the wire is soft and long. Good feedability can be obtained even when the conduit cable is used and welded at a high current, which greatly contributes to the productivity of the gas shielded arc welding wire and the improvement of welding efficiency.

[Brief description of drawings]

FIG. 1 is a view showing a welding device used in an embodiment of the present invention.

[Explanation of symbols]

 1 Conduit cable 2 Spool 3 Feed motor 4 Torch

Claims (1)

[Claims] 1. Graphite 3 to 10 having a particle size of 10 μm or less using one or two kinds of vegetable oil and animal oil as a base oil.
%, 10 to 30% of molybdenum disulfide having a particle size of 3 μm or less
A wire for gas shielded arc welding, wherein a lubricant consisting of 0.3 to 1.8 g per 10 kg of wire is applied to the surface of the wire.