JPH11217578A - Steel wire for gas shielded arc welding - Google Patents

Abstract

(57) [Summary] [PROBLEMS] Even when a flexible and long conduit cable is bent and used and welded under high current welding conditions, there is no slip at the wire feeding roller portion and the inside of the conduit tube is reduced. The present invention provides a steel wire for gas shielded arc welding, which has a low frictional resistance at a low temperature, has a good wire feedability, and does not easily remove lubricant on the wire surface and does not cause chip clogging. SOLUTION: At least one of molybdenum disulfide and tungsten disulfide is added to the surface of a steel wire for gas shielded arc welding at 10 to 40 wt%, fatty acid having a melting point of 50 ° C. or more, ester of fatty acid monohydric or dihydric alcohol or petroleum wax. 5 to 30% by weight of at least one kind of metal soap, 10 to 40% by weight of one or more kinds of metal soap, 2 to 15% by weight of one or more kinds of lubricant, and the rest mainly contains a lubricant mainly composed of a liquid at room temperature.
It is characterized by having 0.2-1.8 g per kg.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas shielded arc welding steel wire, and more particularly to a gas shielded arc welding having excellent wire feedability even when welding using a soft and long conduit cable. Related to steel wire.

[0002]

2. Description of the Related Art Steel wires for gas shielded arc welding (hereinafter referred to as wires) have a wire diameter of 0.8 to 2.0 m.
There are two types of wires, solid wire and flux-cored wire, with a small diameter of m. Among them, the flux-cored wire is a seamless flux-cored wire and strip steel that can be manufactured by plating or wet drawing without a seam. There is a flux-cored wire with seams that is filled with flux, wrapped and manufactured by dry drawing. Of these wires, solid wire and seamless flux cored wire do not have a seam, so copper plating can be applied to the tip attached to the tip of the welding torch during welding, which is advantageous for electrical conductivity and rust resistance of the wire. Since there is no part, it is difficult to give directionality to the wire, there is little wire runout at the tip of the welding torch, and there is little meandering of the weld bead, so it is suitable for welding by robots and is used favorably.

[0003] These wires tend to be used more and more as the automation and efficiency of welding progress. However, recently, in order to further increase the efficiency, regardless of automatic or semi-automatic welding, a higher current density is required. Welding conditions are in the direction of adoption, which inevitably increases the wire feed speed. In addition, depending on the structure to be welded, welding is often performed in narrow parts, and the conduit cable from the wire feeder of the welding machine to the welding torch is bent in terms of ease of use in those places. It tends to be soft and long for ease of use. Generally, a conduit tube in a conduit cable is formed by winding a metal wire having a diameter of 0.8 to 3 mm in a helical manner without any gap and having an inner diameter that is about 0.5 mm larger than the diameter of a wire to be fed. Therefore, the difference between the diameter of the wire to be fed and the inner diameter of the conduit tube is very small, and the length and bend of the conduit cable greatly changes the feed resistance of the wire, and the influence of the wire surface is extremely large.

[0004] As described above, when the wire feeding speed is increased and a long and easily bendable conduit cable is used, frictional resistance is increased when the wire passes through the conduit tube of the conduit cable during wire feeding. In addition, there is a problem in that wire feeding during welding is hindered, and the arc becomes unstable, making welding impossible. To solve the problem of feedability of these wires, for example,
No. 0-3256, a method of applying an oil-based lubricant to a wire surface, and Japanese Patent Publication No. 63-15073, a mixture of a solid lubricant such as graphite, molybdenum disulfide, and glass powder is applied to the wire surface. And various wires such as a wire drawn with a lubricant composed of polytetrafluoroethylene, molybdenum disulfide, graphite and the like and a flux-cored wire coated with the lubricant have been proposed in Japanese Patent Application Laid-Open No. 5-23731. I have.

[0005] However, these wires are also used under the severe conditions in which the above-mentioned soft and long conduit cable is bent and used and high-current welding wires are welded by high-speed feeding. The wire slips at the feeding roller portion of the feeding device, or the frictional resistance in the conduit tube increases, thereby hindering the feeding of the wire during welding and causing unstable arcing. Further, as shown in FIG. 1, the lubricant on the surface of the wire 3 comes into contact with the helical metal wire 1 in the conduit tube 2 in which the metal wire 1 is helically wound, and is separated for a long time as shown in FIG. When welding, the lubricant 4 is accumulated in the valley of the spiral metal wire 1,
The contact area between the wire and the inner surface of the conduit tube 2 increases, the frictional resistance increases, the wire feed resistance increases, and the lubricant accumulated on the inner wall of the chip is brought in. In some cases, welding cannot be performed.

[0006]

SUMMARY OF THE INVENTION Accordingly, the present invention is directed to a method for bending a flexible and long conduit cable, and in a case where welding is performed under a high current welding condition, a slip is generated at a wire feeding roller portion. It is an object of the present invention to provide a gas shielded arc welding steel wire that has no wire friction, a low frictional resistance in a conduit tube, a good wire feedability, and a lubricant on the wire surface that is hard to be separated and that does not cause chip clogging. I do.

[0007]

The gist of the present invention is that at least one of molybdenum disulfide and tungsten disulfide is coated on the surface of a steel wire for gas shielded arc welding by 10 to 40 wt.
%, At least one of fatty acids, esters of fatty acid monohydric or dihydric alcohol or petroleum wax,
30 wt%, at least one kind of metal soap is 10 to 40 wt%,
One or more kinds of lubricants are contained in an amount of 2 to 15% by weight, and the rest is mainly composed of a liquid lubricant of 0.2 to 10 kg per wire at room temperature.
It is a steel wire for gas shielded arc welding characterized by having 1.8 g.

[0008]

DETAILED DESCRIPTION OF THE INVENTION At least one of molybdenum disulfide and tungsten disulfide, at least one fatty acid having a melting point of 50 ° C. or more, at least one ester of a monohydric or dihydric alcohol of fatty acid or petroleum wax, and at least one of a metallic soap At least one kind of lubricating material is contained, and the remainder contains an appropriate amount of a lubricant mainly composed of a liquid at normal temperature, so that even when a flexible and long conduit cable is bent and used, wire feeding can be performed. Since there is no slippage at the rollers and there is little frictional resistance in the conduit tube, the wire feedability is good, and the lubricant on the wire surface is hard to separate, causing no chip clogging and welding with stable arc for a long time. It becomes possible.

These effects can be achieved by the coexistence effects and synergistic effects of the respective compositions, and the reasons for limiting the compositions and the contents thereof will be described below. First, molybdenum disulfide and tungsten disulfide have an effect of reducing frictional resistance in a conduit tube, and one or more of them is set to 10 to 40 wt%. At least one of molybdenum disulfide and tungsten disulfide is 10w
If it is less than t%, the frictional resistance between the wire surface and the spirally wound metal wire in the conduit tube becomes large, and the wire feedability becomes poor. Conversely, if it exceeds 40 wt%, the lubricating property is excessive at the wire feeding roller portion, the wire slips, and the feeding becomes uneven, and the arc becomes unstable. Preferably, at least one of molybdenum disulfide and tungsten disulfide has 0.05 g or more per 10 kg of wire.

It is necessary that the content of at least one of fatty acids having a melting point of 50 ° C. or more, esters of fatty acid monohydric or dihydric alcohol, and petroleum wax is 5 to 30% by weight. These are water repellent and have a rust prevention effect. Further, molybdenum disulfide and tungsten disulfide can be uniformly maintained.
If the melting point of fatty acids, etc. is less than 50 ° C, the conduit becomes hot due to frictional heat between the wire and the spirally wound metal wire in the conduit tube and heat generated by the welding cable surrounding the conduit cable during long-time welding. In the tube, the fatty acid, ester of fatty acid monohydric or dihydric alcohol, petroleum wax, or the like is melted on the wire surface and partially detached, and the amount of molybdenum disulfide and the like is reduced to cause friction in the conduit tube. The resistance increases and the wire feedability becomes poor. Further, when the separated lubricant is accumulated in the conduit tube and welded for a long time, the feeding resistance increases and the arc becomes unstable.

If the content of at least one of fatty acids having a melting point of 50 ° C. or more, esters of fatty acid monohydric or dihydric alcohol, and petroleum wax is less than 5 wt%, adhesion of molybdenum disulfide and tungsten disulfide will be poor. Therefore, the frictional resistance in the conduit tube increases, and the wire feeding property becomes poor. Conversely, if it exceeds 30 wt%, it will separate in the conduit tube, accumulate, and if welding for a long time, the frictional resistance with the wire surface will be large, and the wire will slip at the wire feeding roller section, resulting in uneven wire feeding and arcing. Becomes unstable.

The fatty acid in the present invention refers to those having a melting point of 50 ° C. or more, such as myristic acid, palmitic acid, stearic acid, and melicic acid. It refers to those having a melting point of 50 ° C. or more, such as wax, cotton wax, and synthetic waxes of higher fatty acids. In addition, petroleum wax refers to those having a melting point of 50 ° C. or more obtained by petroleum refining, such as solid paraffin and petrolatum.

One or more of the metal soaps is 10 to 40% by weight. Metal soap is made of fatty acid, fatty acid monohydric or dihydric alcohol ester and petroleum braze firmly attached to the wire surface to reduce the wire slip at the wire feed roller, and stable with long conduit cables even under severe bending conditions In addition, the lubricant can be removed in the feed roller groove and the conduit tube, so that the friction resistance in the conduit tube is reduced, and the clogging of the chip hardly occurs.

If the metal soap is less than 10% by weight, fatty acids, esters of monohydric or dihydric alcohols of fatty acids and petroleum wax cannot be firmly adhered to the wire surface, so that the inside of the feed roller and the conduit tube may not be adhered. Accumulated, the wire slips at the feeding roller portion, and the frictional resistance increases in the conduit tube, so that the arc becomes unstable. If the metal soap exceeds 40 wt%, the amount of Na and K components on the surface of the wire will increase, causing arc breakage and increasing the amount of spatter generated. The metal soap refers to sodium stearate, K stearate, Li stearate, Ba stearate and the like.

[0015] At least one kind of the lubricating material needs to be 2 to 15 wt%. These further reduce the wire feed resistance in the conduit tube without promoting wire slipping at the wire feed roller during welding. Lubricant 1
No effect is obtained when the content of the seeds is less than 2 wt%, and 15 wt%
If it exceeds, it is separated and accumulated in the conduit tube, the frictional resistance increases, and the arc becomes unstable. In addition, the lubricating material referred to in the present application refers to talc, mica, sericite, and the like, and is preferably a fine powder of 74 μm or less.

One or more of molybdenum disulfide and tungsten disulfide on the surface of the wire, one or more of fatty acids having a melting point of 50 ° C. or more, esters of monohydric or dihydric alcohols of fatty acids and petroleum wax, and one of lubricating materials Above and the rest, the amount of lubricant mainly consisting of liquid at normal temperature, diameter 0.8 ~
0.2-1.8 g is required per 10 kg of 2.0 mm wire. If it is less than 0.2 g, the frictional resistance is large in the conduit tube, and the wire feeding property becomes poor.
If it exceeds 8 g, the wire will slip at the wire feeding roller portion, causing uneven feeding and making the arc unstable. Also,
Friction resistance increases when welding is performed for a long time by detaching and accumulating in the conduit tube.

In addition to the above molybdenum disulfide and tungsten disulfide, fatty acids having a melting point of 50 ° C. or higher, esters of fatty acid monohydric or dihydric alcohol or petroleum wax, lubricants and lubricants which are liquid at room temperature, In order to adjust the amount of the lubricant, an inorganic carrier material such as a carbonate, a metal oxide, a silicate and a fluoride can be contained in an amount of 10 wt% or less. The steel wire for gas shielded arc welding of the present invention refers to a solid wire such as a Si-Mn-based or Si-Mn-Ti-based wire specified in JIS Z3312, or a flux-cored wire specified in JIS Z3313, and has a diameter of 0.8. It is a small-diameter wire of about 2.0 mm.

[0018]

The present invention will be described in more detail with reference to the following examples. First, the amounts of molybdenum disulfide and tungsten disulfide on the surface of the wire, fatty acids having a melting point of 50 ° C. or higher, esters of monohydric or dihydric alcohol of fatty acids or petroleum wax, lubricant and liquid lubricant shown in Table 1 were varied. Solid wire of YGW11 specified in JIS Z3312 having a wire diameter of 1.2 to 1.6 mm and JISZ3
A prototype of a YFW-C50DR seamless flux-cored wire (with a flux filling rate of 15%) specified in 313 was used as a spool-wound wire.

[0019]

[Table 1]

The apparatus shown in FIG. 3 was used for investigating the wire feedability. That is, a 6 m loop provided with two rotations of 150 mm in diameter for the purpose of increasing the frictional force in the conduit tube and increasing the frictional resistance between the wire and the conduit tube.
The wire 3 pulled out of the spool 6 is fed to the conduit cable 5 by a feed motor 7 so that the welding torch 8
And welded 15 kg of wire in each test. Table 2 shows the welding conditions at that time. The conduit tube used had a metal wire diameter of 1.6 mm and an inner diameter of 2.0 mm.

[0021]

[Table 2]

The wire feedability was examined by measuring the armature current of the feed motor 7. When the armature current exceeds 3.5 A in the wire feedability, the protruding length of the wire changes and the arc becomes unstable. The slip of the wire at the wire feed roller portion was determined by measuring the peripheral speed (T) of the feed roller and the wire speed (W) at the outlet of the feed roller, and calculating the slip ratio by the following equation. If the slip ratio of the wire exceeds 5%, the speed of the wire feed will fluctuate and the arc will become unstable due to uneven wire feed. Slip ratio = (T−W) / T × 100 Further, a conduit tube that is not used for each prototype wire is used, and after welding is completed, a loop portion of the conduit tube is cut to lubricate the spiral metal wire. The accumulation status of the agent was examined. Table 3 shows the results.

[0023]

[Table 3]

In Table 3, Test No. Nos. 1 to 8 are steel wires for gas shielded arc welding according to the present invention. 9
To 19 are comparative examples. Test No. of the present invention example. 1-8
The amounts of molybdenum disulfide and tungsten disulfide on the surface of the wire, fatty acids having a melting point of 50 ° C. or more, esters of fatty acid monohydric or dihydric alcohol, petroleum brazing wax and lubricant are appropriate. Since the amount is appropriate, the slip ratio of the wire at the time of welding and the armature current of the feed motor are low, the arc is stable, and the lubricant is less likely to be released into the conduit tube, which is a very satisfactory result.

Test No. in the comparative examples. In No. 9, the total amount of molybdenum disulfide and tungsten disulfide was large, slipping occurred at the wire feeding roller portion, the slip ratio was increased, and the arc was unstable. Test No. In Test No. 10, the total amount of molybdenum disulfide and tungsten disulfide was small. In Test No. 13, the total amount of fatty acids having a melting point of 50 ° C. or higher, esters of monohydric or dihydric alcohols of fatty acids, and petroleum wax was small. In No. 19, since the lubricant content per 10 kg of the wire was small, the friction resistance of the wire in the conduit tube was increased, the armature current of the feed motor was increased, and the arc was unstable.

Test No. Test No. 11 has a low melting point of fatty acids, esters of fatty acid monohydric or dihydric alcohols, and lanolin, which is a kind of petroleum wax. 16 is
Since the total amount of the lubricating material was large, the frictional resistance of the wire in the conduit tube was increased, the armature current of the feed motor was increased, and the arc was unstable. In addition, a large amount of lubricant separated in the conduit tube was observed.

Test No. Test No. 12 has a large total amount of fatty acids having a melting point of 50 ° C. or higher, esters of fatty acid monohydric or dihydric alcohol, and petroleum wax. Test No. 15 has a small amount of metal soap. No. 18 has a large lubricant content per 10 kg of wire, so that the wire feed roller slips to increase the slip ratio, and the frictional resistance of the wire in the conduit tube increases, so that the armature current of the feed motor increases. And the arc was unstable. Further, a large amount of the lubricant separated in the conduit tube was observed.

Test No. In No. 14, since the total amount of the metal soap was large, the arc was cut off and the amount of spatter generated was large.
Test No. In No. 16, the total amount of the lubricant was large, the frictional resistance of the wire in the conduit tube was increased, the armature current of the feed motor was increased, and the arc was unstable. In addition, a large amount of lubricant separated in the conduit tube was observed. Test No. In No. 17, since the amount of the lubricating material was small, the armature current of the feed motor was slightly increased, and the arc became slightly unstable.

[0029]

As described in detail above, according to the steel wire for gas shielded arc welding of the present invention, when a soft and long conduit cable is used by bending and is welded under high current welding conditions. Also, there is no slip in the wire feeding roller part, the friction resistance in the conduit tube is small, the wire feeding property is good, the lubricant on the wire surface is hard to separate and the tip does not clog, even for a long time It has excellent effects such as stable welding of the arc.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a state where a wire is fed through an inner surface of a conduit tube.

FIG. 2 is a cross-sectional view showing a state in which lubricant has been separated and accumulated in a conduit tube.

FIG. 3 is a view showing a welding device used in an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Spiral metal wire 2 Conduit tube 3 Wire 4 Accumulated lubricant 5 Conduit cable 6 Spool 7 Feed motor 8 Welding torch

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C10M 105/32 C10M 105/32 // C10N 10:02 10:12 20:00 40:32

Claims (1)

[Claims] 1. A steel wire for gas shielded arc welding, on the surface of which at least one of molybdenum disulfide and tungsten disulfide is present in an amount of 10 to 40% by weight, a fatty acid having a melting point of 50 ° C. or more, an ester of a fatty acid monohydric or dihydric alcohol or petroleum. 5 to 30 wt% of at least one kind of wax, 10 to 40 wt% of at least one kind of metal soap, 2 to 15 wt% of at least one kind of lubricating material, and a balance of a lubricant mainly composed of a liquid at room temperature.
A steel wire for gas shielded arc welding characterized by having 0.2 to 1.8 g per kg.