JPH06285677A - Steel wire for arc welding - Google Patents

Abstract

PURPOSE:To provide a steel wire for arc welding with excellent feedability even in the case where a soft and long conduit cable is used, and the welding is executed under the condition of high current. CONSTITUTION:The ester film consisting of the fatty acid and alcohol is provided on the surface of the steel wire for the arc welding, and 0.2-1.8g per 10kg of the wire including the ester the lubricant containing 20-50% tetrafluoride ethylene, 5-30% molybdenum disulfide, and 20-50% of one or more kinds of Ca compounds, Na compounds, and glass powder is coated.

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 arc welding, and more particularly to a steel wire for arc welding which is excellent in feedability during welding.

[0002]

2. Description of the Related Art Steel wires for arc welding tend to be used more and more with the progress of automation and high efficiency of welding, but recently, due to efficiency, high current welding is possible regardless of automatic or semi-automatic welding. Conditions are being adopted. As a result, the wire feeding speed is inevitably high. 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.

As described above, when the welding steel wire is supplied at a high speed and is used in a long and easily bendable conduit cable, friction resistance occurs when the wire passes through a conduit tube in the conduit cable during wire feeding. Becomes large, which hinders the wire feeding during welding, and the arc becomes unstable so that welding cannot be performed. For this reason, various measures have been taken so far for welding steel wire in order to improve the wire feedability, but it is not sufficient yet, and welding workers often weld under severe conditions. We are forced to suspend the operation, and we have a hard time responding to such problems, such as replacing the rubbed conduit tube.

With respect to these problems of the feedability of the steel wire for welding, conventionally, for example, in JP-A-58-46398, lubrication in which higher fatty acids and alkali metal salts of higher fatty acids are diluted with a volatile solvent is used. Steel wire for welding, which has been drawn with an agent and adhered to the wire surface in an appropriate amount, or JP-A-58-18
Japanese Patent No. 4095 proposes a steel wire for arc welding in which a mixture of solid lubricants such as graphite, molybdenum disulfide and glass powder is applied to the surface of the steel wire.

[0005]

However, even in these steel wires for arc welding, the above-mentioned soft and long conduit cable is used, and under severe conditions such as welding under high current conditions, it still remains. The current situation is insufficient. Therefore, it is an object of the present invention to provide a steel wire for arc welding, which uses a soft and long conduit cable and has good feedability even when it is welded under high current conditions.

[0006]

As a result of various studies on lubricants applied to the surface of steel wire for arc welding, the inventors of the present invention have an ester film on the surface of steel wire for arc welding and It has been found that by applying an appropriate amount of one or more of ethylene, molybdenum disulfide, Ca compound and Na compound, and glass powder, the wire feedability under severe current conditions and high current conditions is extremely good. It is a thing.

That is, the gist of the present invention is
The steel wire for arc welding has a film of ester consisting of fatty acid and alcohol, and has 20 to 50 parts of tetrafluoroethylene.
%, 5 to 30% molybdenum disulfide, 20 to 50% of one or more of Ca compound, Na compound and glass powder, and 0.2 to 1.8 g per 10 kg of wire including the ester. Is characterized by.

[0008]

[Function] Since the steel wire for arc welding has a film of ester composed of fatty acid and alcohol, the lubricant can be evenly distributed on the surface of the steel wire for arc welding, and the feedability during welding is improved. . The fatty acid referred to in the present invention refers to animal and plant fatty acids. Further, the ester film is formed by passing the arc welding steel wire into the ester bath or by using a roll or felt before at least the final skin pass of the arc welding steel wire manufacturing process.

A lubricant is applied after the ester film, and the lubricant is applied at least in the die box of the final skin pass. The evenly distributed lubricant makes the feedability of the steel wire for arc welding extremely good when a soft and long conduit cable is used during welding and is welded under high current conditions. These effects can be achieved by the coexistence effect and synergistic effect of each lubricant as well as the film ester. The reasons for limiting each lubricant will be described below.

First, the content of ethylene tetrafluoride in the lubricant is 20 to
Must be 50%. If the content of ethylene tetrafluoride is less than 20%, the feedability of the steel wire for arc welding becomes poor. On the other hand, when it exceeds 50%, the feedability is good but the amount of spatter is increased. 5-30% molybdenum disulfide
Must be If it is less than 5%, feedability is poor,
If it exceeds 30%, welding fumes and spatters increase. 1 of Ca compound, Na compound and glass powder
It is necessary to be 20 to 50% of seeds or more. If it is less than 20%, wire surface scratches occur when the lubricant is applied by a die, and the wire feedability becomes poor due to these scratches. If it exceeds 50%, it will remain in the welding tip as a solid and clogging of the tip will occur. Note that the Ca compound and Na compound refer to these carbonates, fluorides, silicates, and the like. Further, the glass powder, silicate glass, soda glass, potash glass,
A powder such as soda-lime glass.

Next, the coating amount of the lubricant including the ester on the steel wire for arc welding of the present invention must be 0.2 to 1.8 g per 10 kg of the wire. If it is less than 0.2%, the feedability will be poor, and if it exceeds 1.8 g, the lubricant will remain in the chip, causing chip clogging. The amount of lubricant applied to the surface of the steel wire for arc welding is controlled by the diameter reduction ratio in the final skin pass. 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.

[0012]

The present invention will be described in more detail with reference to the following examples. First of all, the wire diameter was varied by varying the presence or absence of an ester film on the surface of the steel wire for arc welding, the lubricant composition, and the amount.
YGW specified in JIS 3312 of 2 to 1.6 mm
11 solid wires and a YFW24 seamless flux-cored wire (flux filling rate 14%) specified in JIS Z3313 were prototyped. The apparatus shown in FIG. 1 was used to investigate the wire feedability. That is, for the purpose of increasing the feeding resistance, the wire pulled out from the spool 2 is fed by the feeding motor 3 to the 6 m conduit cable 1 provided with two loops of 200 mm in diameter and fed to the torch 4, 10 kg of wire each. Welded. The welding conditions at that time are as shown in Table 1.

[0013]

[Table 1]

The wire feedability was examined by measuring the armature current of the feed motor 3. The wire feedability becomes defective when the armature current exceeds 3.5 A, and the arc becomes unstable. The results are summarized in Table 2.

[0015]

[Table 2]

In Table 2, Test Examples 1 to 5 are steel wires for arc welding according to the present invention, and Test Examples 6 to 14 are comparative examples.
In Test Examples 1 to 5 of the present invention, the armature current of the feed motor during welding was low and the arc was stable, which was a very satisfactory result. In Comparative Example 6, in Test Example 6, the ester coating was not present, so the lubricant was not uniformly distributed, the armature current of the feed motor during welding was high, and the arc was unstable. In Test Example 7, since the amount of ethylene tetrafluoride in the lubricant was large, the armature current was low but the amount of spatter generated was large.

In Test Example 8, the amount of ethylene tetrafluoride in the lubricant was small, and in Test Example 10, since the amount of molybdenum disulfide was small, the armature current was high and the arc was unstable. In Test Example 9, since a large amount of molybdenum disulfide was contained in the lubricant, a large amount of fumes and spatters were generated. In Test Example 11, since the total amount of Ca compound, Na compound and glass powder in the lubricant was large, chip clogging occurred.

Test Example 12 is the Ca compound in the lubricant, N
Since the total amount of the a compound and the glass powder was small, surface scratches were generated during wire drawing, and the armature current increased due to the scratches during welding, and the arc became unstable. Test Example 13
Has a large amount of ester and lubricant per 10 kg of wire, so that chip clogging occurred. In Test Example 14, since the amount of ester and lubricant per 10 kg of wire was small, the armature current was high and the arc was unstable.

[0019]

As described in detail above, according to the steel wire for arc welding of the present invention, good feedability is obtained even when a soft and long conduit cable is used and welding is performed at high current. Is obtained, which greatly contributes to the improvement of welding efficiency.

[Brief description of drawings]

FIG. 1 is a diagram 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. A steel wire for arc welding having a film of an ester consisting of fatty acids and alcohols, which comprises 20 to 50% of tetrafluoroethylene, 5 to 30% of molybdenum disulfide, Ca compound, Na compound and glass powder. 20 to 1 or more
A wire containing 50% of a lubricant including the ester.
A steel wire for arc welding, characterized in that 0.2 to 1.8 g per kg is applied.