JPH08252691A - Wire for gas shielded metal arc welding - Google Patents

Abstract

PURPOSE: To provide a wire for gas shielded metal arc welding to provide excellent wire feedability even in the case where a long conduit wire is used and the welding is achieved under the bending load. CONSTITUTION: In this wire for the gas shielded metal arc welding, the surface of the wire where the mean interval H of the projections on the wire surface is <=150μm, the mean roughness Ra of the projection of the wire surface is 0.4-3.0μm, and the maximum height Ry of the projection is <=15μm is coated with the lubricating composite alloy. The liquid lubricant of 0.2-1.0g per 10kg of the wire is applied on the wire surface coated with the lubricating composite alloy.

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 wire (hereinafter, referred to as a welding wire), and particularly, in the case of welding using a bent long conduit cable, excellent feedability can be obtained. Related welding wire.

[0002]

2. Description of the Related Art Welding wires generally have a wire diameter of 0.8 to
There are solid wires with a 2.0 mm fine wire whose entire cross section is metal, and flux-cored wires in which the flux is covered with a steel sheath. During welding, these wires are inserted into a tubular body containing a flexible tube spirally formed inside the conduit cable (hereinafter referred to as conduit tube) by a supply roller of a wire supply device while being inserted into a long length. It is used in a method of arc melting in a shield gas atmosphere while continuously sending out a wire from a conduit cable (6 m or more) and a contact tip (current carrying part) of a welding torch connected to it.

In welding, a long conduit cable must be bent vertically or horizontally to adjust the distance from the welding power source to the welding site, or wound in a loop to adjust the length. Is often. Further, in a narrow welding site, a conduit cable immediately before the welding torch is often bent into an S shape or a J shape for use. In this case, when the conduit cable is bent, a wire passing through the inside of the conduit tube has an increased contact friction portion with the inner surface of the conduit tube, which increases the feeding resistance, which makes it difficult to smoothly feed the wire. Become.

Therefore, in the past, there have been proposals for improving the feedability of the wire when manufacturing the welding wire. That is, a method of making a wire surface uneven and then applying a lubricant thereto, for example, in JP-A-61-27198, a shot blasting process using a shot having an average particle diameter of 50 to 750 μm is performed on the wire surface to obtain a lubricant. Is proposed to be applied. As a lubricant for improving the wire feeding property, generally, a fixed amount of vegetable oil, animal oil and mineral oil or a mixed oil thereof is applied to the wire surface. When the operating conditions are more severe, a solid lubricant such as MoS ₂ or graphite powder is suspended in the above oily liquid lubricant and applied on the wire surface.

[0005]

When the wire surface is made uneven, slippage of the wire is reduced at the wire feeding roller portion, but the wire surface unevenness for improving the feeding property is not specified to a certain range. As a result, the wire slips at the feeding roller portion or becomes frictional resistance in the conduit tube, which adversely affects the feeding performance. Further, even if the liquid lubricant is applied to the surface of the wire, if load resistance is applied to the conduit tube, the wire slips at the feeding roller portion and a stable arc cannot be obtained. It is difficult to uniformly apply a solid lubricant such as MoS ₂ or graphite powder to the wire surface, and the wire feedability under the severe conditions as described above becomes extremely poor. Therefore, an object of the present invention is to provide a wire for gas shielded arc welding, which uses a long conduit cable and has good wire feedability even when it is welded under a bending load. And

[0006]

Means for Solving the Problems The present invention achieves the above object. The gist of the present invention is that in a wire for gas shielded arc welding, the average distance H between wire surface protrusions is 150 μm or less, The average roughness Ra is 0.4 to 3.0 μm, and the maximum height Ry of the protrusion is 15
The surface of the wire having a thickness of less than μm is coated with a lubricating complex alloy. In addition, a liquid lubricant is applied to the wire 10
It is also characterized in that 0.2 to 1.0 g is applied per g.

The wire surface protrusion average spacing H is the average spacing of the maximum diameters when the protrusions are circular, and the average spacing between adjacent protrusions when the protrusions are linear. In addition, the average roughness Ra of the wire surface protrusion and the maximum height Ry of the protrusion are JIS B060.
The value is measured by the method according to 1. In addition, the lubricous composite alloy refers to one obtained by sintering tungsten disulfide and iron powder, molybdenum disulfide and iron powder, tungsten disulfide and stainless powder, molybdenum disulfide and stainless powder, and the like.

[0008]

FIG. 1 is an explanatory view showing a wire feeding process.
The welding wire 1 is sequentially fed by the flat pressure feeding roller 2 and the V-grooved feeding roller 3 of the wire feeding portion by driving the feeding motor from a state of being set in the wire feeding device (not shown), It is supplied from the conduit cable 4 to the welding portion through the welding torch 5. At this time, the wire 1 is pressed by the flat pressure feeding roller 2 and the V-grooved feeding roller 3 of the wire feeding unit, and when the wire tries to enter the V-grooved feeding roller 3 due to its vertical load. V
A contact portion with the grooved feeding roller 3 is generated, and a frictional force due to the contact acts to serve as a feeding force. Further, for example, since it passes through the conduit cable 4 having a length of 3 to 20 m, the friction resistance changes depending on the amount of lubricant on the wire surface and the shape of the wire surface, and the feedability changes.

FIG. 2 is a schematic diagram of the entire continuous wire drawing processing line. A coil-shaped wire rod 9 is unwound from the pay-off stand 8 while being unwound, and the wire rod 9 unwound from the pay-off stand 8 is drawn at a predetermined working rate by a tandem-arranged wire drawing die equipped with a wire drawing machine 10. The wire rod 9 forms projections on the surface of the wire rod by a roller die 11 in which shot blasting or concave portions are formed on the roller, the surface of the wire rod is coated with the lubricous complex alloy coating device 12, and then by the final finishing die 13. The wire rod 9 drawn to the final diameter is wound around the take-up capstan 14 and then oil-coated by the oil coating device 15 to wind the winding machine 1.
Take up by 6.

In measuring the feedability of the welding wire manufactured in this manner, when a load is applied to the wire 1 sent from the wire feeder, the wire 1 is retracted by the reaction force of the wire feeder. However, the force generated at this time is measured as the feeding resistance R by the load cell 6. Also, the slip ratio S
Is installed at the peripheral speed (TG) of the feeding roller and the welding torch 5 and the passing speed of the wire (P
G) is measured and calculated by the following formula. Slip rate S = (TG-PG) 100 / TG

FIG. 3 is an explanatory view showing the state of the wire surface protrusions and the coating of the lubricating composite alloy according to the present invention, which are produced by the continuous wire drawing treatment line. The average distance H between the wire surface protrusions shown in FIG. 3 is set to 150 μm or less. When the average wire surface protrusion distance H exceeds 150 μm, the distance between adjacent protrusions on the wire surface is too wide, and the feeding force at the wire feeding roller decreases and the slip ratio S increases.
It cannot maintain good feedability.

Further, the average roughness Ra of the wire surface is 0.4.
˜3.0 μm, and the maximum height Ry of the protrusion is 15 μm or less. If the average surface roughness Ra of the wire surface is less than 0.4 μm, no frictional force is generated at the feeding roller, which reduces the feeding force and increases the slip ratio S, thereby maintaining good feeding performance. I can't. Average roughness of wire surface R
When a exceeds 3.0 μm, the maximum height of the protrusion Ry
Is more than 15 μm, the feeding force at the feeding roller is large, but the frictional resistance in the conduit tube is large and the feeding resistance R is large, so that the feeding property is deteriorated. In addition, if the projection scrapes the contact tip and welds for a long time, the electrical conductivity deteriorates and the arc becomes unstable. The density of wire surface protrusions is preferably 15% or less.

The lubricating composite alloy 17 coated on the surface of the wire maintains the frictional force at the feeding roller portion,
Since the frictional resistance in the conduit tube can be reduced, extremely good feedability can be obtained. If the surface of the wire is not coated with the lubricating composite alloy, it is impossible to achieve both the slip ratio S at the feeding roller portion and the reduction of the feeding resistance R in the conduit tube.

Next, the liquid lubricant applied to the surface of the wire is mainly intended to prevent rusting of the wire, but the amount applied to the surface of the wire is 0.2 to 1.0 g per 10 kg of the wire.
If the coating amount of the liquid lubricant is less than 0.2 g, the rust preventive effect of the wire will be reduced. Further, when it exceeds 1.0 g, the feeding force at the feeding roller portion becomes low, the slip ratio S becomes high, and the feeding performance becomes poor. The liquid lubricant refers to oil lubricants such as palm oil, rapeseed oil and silicone oil.

FIG. 4 is an explanatory view for forming the protrusion according to the present invention. As one example of the method for drawing a wire for welding having a projection according to the present invention by roller die rolling, as shown in FIG.
Two roller dies composed of a pair of grooved rollers 18 and 19 which face each other with the wire sandwiched therebetween are alternately arranged in a wire rolling direction of 9
They are arranged close to each other so that they change by 0 °, and this is configured as a unit of one roller die. Therefore, in one roller die, the roller shafts adjacent to each other in the wire drawing direction are 9
Vertically and horizontally arranged at 0 ° intervals. A recess is formed in the roller die, and the recess is formed by spraying a metal such as a hard tungsten carbide or ceramics on the groove of the roller die, or by using a high-density energy source such as a laser. In addition, as a method of manufacturing a welding wire having other protrusions, it is possible to use spherical steel and hard slag to perform shot blasting on the wire surface to form the wire.

FIG. 5 shows an example of coating the surface of a wire with the lubricous composite alloy according to the present invention. As shown in FIG. 5, the welding wire 1 is sandwiched between the lubricating composite alloys so that the entire circumference of the wire surface can be coated, and the welding wire 1 is uniformly coated. The coating amount of the lubricating complex alloy on the wire surface is 0.3 to 1.
It is preferably 0 g).

[0017]

EXAMPLES The present invention will be specifically described below with reference to examples. Solid wire for gas shielded arc welding with copper plating (JIS Z3312 YGW
11 C: 0.08%, Si: 0.78%, Mn: 1.
63%, P: 0.012%, S: 0.014%, Ti:
Using 0.18% balance Fe and unavoidable impurities), wire drawing was performed to obtain wires having diameters of 1.2 mm and 1.6 mm. Each of the test wires was provided with a different surface protrusion, and a 6 m long conduit cable was used in the apparatus shown in FIG.
By changing the loop diameter D and the number of loops of the conduit cable 4 shown in Table 1, welding was performed under the welding conditions shown in Table 1, and the wire feeding resistance R and the slip ratio S during wire feeding were measured. In addition, the lubricating composite alloy coated on the wire surface is
A mixture of 30% tungsten disulfide powder and 70% SUS310 stainless steel powder and sintered at high temperature was used. Palm oil was used as the lubricant applied to the wire surface. The results are shown in Table 2.

[0018]

[Table 1]

In Table 2, Nos. 1 to 6 are gas shield arc welding wire examples of the present invention, and Nos. 7 to 12 are comparative examples. In Nos. 1 to 6 of the present invention example, the average spacing H of the wire surface protrusions is 150 μm or less, and the average roughness Ra of the wire surface protrusions is Ra.
Is 0.4 to 3.0 μm, and the maximum height Ry of the protrusion is 1
The surface of the wire having a thickness of 5 μm or less is coated with a lubricous complex alloy, and the liquid lubricant is added to 0.2 to 10 kg of the wire.
Since 1.0 g was applied, the feed resistance R was low and the slip ratio S was low even under a very severe condition such as a loop diameter of 100 mm2 turns, and the arc was stable, which was a very satisfactory result.

No. 7 in the comparative example is not coated with the lubricous composite alloy, and No. 8 has a too large wire surface protrusion interval H, so that good feedability can be obtained up to 1 turn of the loop diameter of 150 mm. Obtained, loop diameter 150
The slip ratio S was large at mm2 turns, and at the loop diameter of 100 mm2 turns, both the feeding resistance R and the slip ratio S were large, resulting in poor wire feeding performance. In No. 9, since the wire surface protrusion average roughness was small, the slip ratio was large even in one turn of the loop diameter of 150 mm, and the wire feedability was poor.

No. 10 had a large average roughness on the wire surface protrusions, and No. 11 had an excessively large maximum height on the wire surface protrusions, so good feedability was obtained up to a loop diameter of 150 mm per turn. Feeding resistance R for loop diameter 150mm2 turn and loop diameter 100mm2 turn
Became large and the wire feedability became poor. Further, even when the loop diameter was 150 mm and one turn, the arc became unstable when the contact tip was scraped during welding and the welding was performed for a long time. Since No. 12 had too much lubricant applied, good feedability was obtained up to a loop diameter of 150 mm1 turn, but a loop diameter of 150 mm2 turns and a loop diameter of 100
In the mm2 turn, the slip ratio S increased and the wire feedability became poor.

[0022]

[Table 2]

[0023]

According to the wire for gas shielded arc welding of the present invention, even when a long conduit cable is used and is welded under a bending load applied thereto,
Since a good wire with low feed resistance and less wire slip in the feed roller portion can be obtained, it contributes greatly to the welding efficiency.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a wire feeding process.

FIG. 2 is a schematic view of the entire continuous wire drawing processing line.

FIG. 3 is an explanatory view showing a wire surface protrusion according to the present invention.

FIG. 4 is an explanatory view for forming a wire surface protrusion according to the present invention.

FIG. 5 is an explanatory diagram for coating the surface of the wire with a lubricous complex alloy according to the present invention.

FIG. 6 is a diagram showing a conduit cable used in an example of the present invention.

[Explanation of symbols]

 1 Wire 2 Flat Pressure Feeding Roller 3 V-Grooving Feeding Roller 4 Conduit Cable 5 Welding Torch 6 Load Cell 7 Measuring Roller 8 Payoff Stand 9 Wire Rod 10 Wire Drawing Machine 11 Roll Die 12 Lubricating Complex Alloy Coating Equipment 13 Finishing Dies 14 Take-up capstan 15 Oil coating device 16 Winder 17 Coated lubricous complex alloy 18, 19 Grooved roller 20 Lubricative complex alloy

 ─────────────────────────────────────────────────── --- Continuation of the front page (72) Inventor Ko Kato 3-5-4 Tsukiji, Chuo-ku, Tokyo Inside Nittetsu Welding Industry Co., Ltd. (72) Inventor Takuhiko Nishida 1618 Ida, Nakahara-ku, Kawasaki-shi, Kanagawa Nippon Steel Corporation Advanced Technology Research Center

Claims (2)

[Claims] 1. A wire for gas shielded arc welding, wherein an average spacing H of wire surface protrusions is 150 μm or less, an average roughness Ra of wire surface protrusions is 0.4 to 3.0 μm, and a maximum height Ry of the protrusions is 15 μm. A wire for gas shielded arc welding, characterized in that the following wire surface is coated with a lubricating composite alloy. 2. A liquid lubricant is applied to the surface of the wire coated with the lubricating composite alloy in an amount of 0.2 to 10 per 10 kg of the wire.
The wire for gas shield arc welding according to claim 1, wherein 1.0 g of the wire is applied.