JPH082514B2 - Gas shielded arc welding wire manufacturing method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for producing a wire for gas shielded arc welding, which performs arc welding while automatically supplying the wire in a shield gas atmosphere.

2. Description of the Related Art Conventionally, it has been reported that when a trace amount of a metal having a low potential gradient such as cesium, calcium and potassium is attached to the wire surface, the arc discharge phenomenon is stabilized and the welding performance is improved. Further, as a method of adhering the metal to the wire surface, as shown in JP-A-60-231599, a powdery or solid potassium carboxylic acid salt is mixed with a dry lubricant on the wire surface and used. A method of mechanically fixing by a finish wire drawing as a finishing step after copper plating treatment is adopted. FIG. 2 shows an example of the manufacturing process of a conventional gas shielded arc welding wire. That is, in FIG. 2, 11 is a supply coil, 12 is a cleaning step, 13 is an electroplating step, 14 is a cleaning step, 15 is a drying step, 16 is a dry finish wire drawing step, 17 is a winding coil, and 18 is a wire. Indicates. As shown in FIG. 2, conventionally, it has been customary to employ a method in which copper plating is performed by an electroplating method and finish wire drawing is performed by using a dry lubricant.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention In such a conventional production method, since a dry lubricant is used, as described in JP-A-60-231599, as a component of the dry lubricant, "olein" is used. Potassium acid, potassium salts such as potassium palmitate, sodium salts such as sodium oleate, sodium palmitate, sodium stearate, graphite, sulfur,
It was necessary to properly mix the extreme pressure additives such as talc and Zn-DTP and the lubricant.

However, in order to mix the above extreme pressure additives and antifriction agents, the wire surface after dry finishing wire drawing should have the necessary carboxylic acid potassium salt (potassium tetearylate etc.) There is a drawback that additives and lubricants are also fixed at the same time. As a matter of course, substances contained in these extreme pressure additives and lubricants may adversely affect the deposited metal after welding. For example, sulfur or Zn
(Zinc) or the like may generate gas during welding, remain as bubbles in the deposited metal, and may cause defects such as blowholes. Further, in such a conventional method, it is extremely difficult to regulate the amounts of these extreme pressure additives and lubricants to such an extent that they do not affect the welding result. The reason is that if the amount of these extreme pressure additives and lubricants is reduced,
This is because the die for finish wire drawing becomes severely worn and the productivity is significantly reduced.

FIG. 3 shows a wire in which a powdery or solid potassium carboxylic acid salt (potassium stearate, etc.) in a conventional example is mechanically fixed to the wire surface by dry finish drawing.
It is the side view a and the front perspective view b which are shown typically. In FIG. 3, 21 is a wire, 22 is a copper plating film, 23 is a potassium carboxylate salt, and 24 is a free metal powder. That is, as shown in FIG. 3, the conventional manufacturing method has a drawback that a large amount of free metal powder is easily generated.

A method of removing the extreme pressure additive, the lubricant and the free metal powder by a means such as washing after finishing wire drawing is also conceivable. According to this method, the required potassium carboxylic acid salt is used. Since it also removes potassium stearate and the like, it is not practical.

As described in JP-A-60-231599, "liquid potassium stearate dissolved in a solvent, potassium oleate, potassium palmitate, and the like are advantageous for coating, but potassium stearate. Since potassium oleate and potassium palmitate have low solubility in solvents such as potassium oleate and potassium palmitate, the amount of potassium effective for arc discharge does not adhere to the metal surface. " The method of applying it to the wire surface in a liquid state by dissolving it in a solvent such as is advantageous in that there is no adhesion of metal powder, but "To apply a potassium salt effective for arc discharge to the wire surface, the liquid application amount is very This will cause another problem during welding, such as wire slip on the wire feed roller. ” Jo or a solid potassium carboxylate, a dry finishing wire drawing method on the wire surface,
I had no choice but to adopt a mechanical fixing method.

The present invention has been made in view of the above problems, and has a good productivity and a necessary amount of a carboxylic acid potassium salt (such as potassium stearate) deposited on the wire surface, which adversely affects the welding result. It is an object of the present invention to provide a gas shielded arc welding wire having good welding performance by preventing simultaneous deposition of substances and free metal powders which hinder welding performance.

Means for Solving the Problems In order to solve the above problems, the present invention, after performing a copper plating treatment on the wire surface, after washing and drying the wire surface, using a polyhydric alcohol as a solvent, potassium carboxylate salt By holding and adhering the dissolved solution on the wire surface, the potassium carboxylic acid salt is held and adhered on the wire surface by 0.2 g or more and 10 g or less per 10 kg of the wire.

Action The present invention first focuses on the pinholes existing in the copper plating film on the wire surface. That is, generally, the film thickness of copper plating of the gas shielded arc welding wire is 20 μm to 30 μm.
μm is adopted, and with this thickness, the pinhole will not disappear. Therefore, if a solution of potassium carboxylic acid salt (potassium stearate, etc.) can be press-fitted and attached to this pinhole,
It becomes easy to secure the adhesion amount to the wire surface. In other words, by cleaning and drying the plating surface after copper plating, the pinhole becomes empty, and the potassium carboxylic acid salt (potassium stearate, etc.) solution can be retained and attached inside the pinhole. Becomes As a method for holding and adhering the dissolving solution to the pinhole, a wire is dipped in the dissolving solution, or
A method of coating is conceivable, but a more effective method is a finish wire drawing method. It has been reported from the past that wet drawing is more advantageous than dry drawing when drawing thin wires such as wires at high speed. In wet wire drawing, by using a forced lubrication die that has a nozzle at the inlet of the wire drawing die, wire drawing is possible in a fluid lubricated state, die wear is significantly reduced, and productivity is improved. This is because there is an advantage. The present invention draws a lubricant into the die by finish drawing using this forced lubrication die, and the lubricant, that is, potassium carboxylate (potassium stearate) is introduced into the pinhole of the body plating film on the wire surface. It is designed to be press-fitted and attached.

Of course, during finish wire drawing with a die, a slight amount of die indentation is generated on the wire surface, and the lubricant, that is, potassium carboxylate salt (such as potassium stearate), also adheres to the concave portion of the die indentation. Also, in the case of fluid lubrication, the amount of lubricant that adheres to the wire surface and passes through the die increases, so the amount of lubricant that adheres to the wire surface, that is, the amount of potassium carboxylate (such as potassium stearate). Has the advantage of being easy to secure.

Meanwhile, potassium carboxylic acid salts (potassium stearate, etc.) have a drawback that they have low solubility in a solvent such as hot water, ether, or alcohol. In particular, as in the past, when a monohydric alcohol was used, it was difficult to dissolve it, and even if it was dissolved, the monohydric alcohol has a low boiling point and is volatile, so it is very difficult to handle on the wire surface. , Productivity is poor. In the present invention, a method of dissolving a potassium carboxylic acid salt (potassium stearate or the like) in water using a polyhydric alcohol as a solvent was used. The polyhydric alcohol is a water-soluble liquid or solid, but an aqueous solution of potassium carboxylic acid salt can be prepared by using the liquid polyhydric alcohol. For example, glycerin, which is a trihydric alcohol, has a boiling point of 29.
Since it is as high as 0 ° C, it has low volatility and is easy to handle. It should be noted that it is possible to easily adjust the amount of attachment and adhesion to the wire by adjusting the concentration of the potassium carboxylate salt (such as potassium stearate) in the solution.

In addition, since potassium carboxylic acid salts (potassium stearate, etc.) act as an organic corrosion inhibitor, they have an anticorrosion effect in an atmosphere of high temperature or strong acidity. However, since the effect is lost when it is neutral to alkaline, as a countermeasure against this, it is possible to mix an inorganic corrosion inhibitor into the solution, and it is possible to enhance the anticorrosion effect of the entire wire. As the inorganic corrosion inhibitor, nitrous acid or the like can be used, but in this way, other substances are arbitrarily dissolved or dissolved in the solution within a range that does not adversely affect the welding performance and the welding result. , Can be mixed.

Further, a solution of fatty acid has been conventionally used as a wet lubricant, and it is known that friction and wear of a wire drawing die are considerably reduced especially when a trace amount of fatty acid is added to nonpolar mineral oil or the like. . This is because there is a correlation between the chain length of the compound of the lubricant and the friction coefficient, and the longer the chain length, the smaller the friction coefficient. Stearic acid is a long-chain compound with a long chain length, and metal stearate known as metallic soap is effective as a wet lubricant, and calcium stearate and sodium stearate have been conventionally used. It was Focusing on this point, the present invention can achieve both the use of a lubricant that does not add a substance that adversely affects the welding result as much as possible and the arc stabilization. That is, carboxylic acid potassium salt which is a long-chain compound (eg potassium stearate)
By using this solution as a lubricant, the finished wire can be lubricated without adding sulfur or zinc, which adversely affects the welding result, and potassium carboxylate (such as potassium stearate) can be applied to the wire surface. By depositing the necessary amount, it is possible to obtain the effect of stabilizing the arc and improving the welding performance by the action of potassium, which is a metal having a low potential gradient.

Incidentally, as in the process of the conventional example shown in FIG. 2, the copper plating process is generally performed by an electroplating method.
However, compared with the electroplating method and the electroless displacement plating method, the electroless displacement plating method produces more pinholes in the copper plating film. The displacement plating is based on an ionic reaction between copper ions and iron which is observed when iron is immersed in an aqueous solution of copper sulfate, and copper is deposited on the iron as shown below.

In this case, copper on iron is coarse and the adhesion is not good, but in order to prevent it, a method of adding a small amount of an inhibitor that suppresses dissolution of iron to an aqueous solution of copper sulfate may be adopted. In this way, displacement plating has many pinholes,
As in the present invention, it is suitable for holding a solution of potassium carboxylic acid salt (potassium stearate or the like) in a pinhole of plating under pressure. By the finishing wire drawing,
It is generally known that the adhesion of plating is improved.

As described above, in the present invention, a potassium carboxylic acid salt (potassium stearate, etc.), which is considered to be effective for arc stability, is dissolved in a polyhydric alcohol as a solvent, and finish-drawn by copper wire plating. By holding and adhering in the pinholes existing in the film, and by holding and adhering in the recesses of the die indentation during finish wire drawing, and by making the finish wire drawing a fluid lubrication state, the die is passed and the wire surface By adhering them, the amount of potassium carboxylic acid salt (such as potassium stearate) retained and adhered can be 0.2 g or more and 10 g or less per 10 kg of plating.
For the proper value of the amount of the retained and adhered material, see the above-mentioned JP-A-60-23.
As described in Japanese Patent No. 1599.

Practical Example FIG. 1 is a block diagram showing one embodiment of the manufacturing process of the gas shielded arc welding wire of the present invention. In FIG. 1, 1 is a supply coil, 2 is a cleaning step, 3 is an electroless displacement plating step, 4 is a cleaning step, 5 is a drying step, 6 is a wet finish drawing step, 7 is a winding coil, and 8 is a wire. Show. First
As shown in the figure, by performing the copper plating step by the electroless displacement plating method, a copper plating film with many pinholes can be obtained, which is advantageous for press-fitting and adhesion of the lubricant. Further, when the finish wire drawing is performed by a wet method, almost no generation of free metal powder, which is a problem in the dry wire drawing method of mechanically fixing the powder, is hardly seen. FIG. 4 is a side view a and a front perspective view b schematically showing plating in the embodiment of the present invention. In FIG. 4, 41 is a wire, 42 is a copper plating film, 43
Is a potassium carboxylic acid salt press-fitted and attached to the pinhole of the copper plating film, and 44 is a potassium carboxylic acid salt attached to the concave portion of the die skid. As shown in FIG. 4, by performing finish wire drawing using a wet lubricant containing potassium carboxylic acid salt (potassium stearate, etc.), it is possible to stabilize arc in pinholes existing in the copper plating film on the wire surface. A required amount of potassium carboxylic acid salt (such as potassium stearate) can be attached. Further, since the finish wire drawing is carried out by a wet method, the wire drawing speed can be increased even with a thin wire, so that the productivity is good.

FIG. 5 is a view for performing fluid lubrication in wet drawing,
Indicates a forced lubrication die. In FIG. 5, 51 is a nozzle,
52 is a washer, 53 is a die, 54 is cooling water, and 55 is a lubricant. That is, when a finish wire drawing is performed by using a forced lubrication die as shown in FIG. 5, the life of the die is remarkably extended and the fluid passes through the die because fluid lubrication is achieved by increasing the wire drawing speed. As a result, it becomes easy to secure the amount of the lubricant, that is, the potassium carboxylate salt (such as potassium stearate) attached to the wire surface. Reference numeral 45 shown in FIG. 4 denotes a potassium carboxylic acid salt (such as potassium stearate) which has passed through the die and adhered to the surface of the wire.

EFFECTS OF THE INVENTION As described above, according to the present invention, potassium carboxylic acid salt (potassium stearate, etc.), which is effective in arc stabilization, is uniformly and stably applied to the wire surface in a necessary amount by an extremely simple method. It can be held and attached,
Wet-finish wire drawing produces high-performance gas-shielded wire with stable performance that can increase the wire-drawing speed and generate almost no free metal powder that adversely affects the welding result on the wire surface. It is an extremely industrially useful and valuable invention that can be provided with good performance.

[Brief description of drawings]

FIG. 1 is a block diagram showing a manufacturing process of an embodiment of the present invention,
FIG. 2 is a block diagram showing a manufacturing process of a conventional example, and FIG.
Is a side view schematically showing a conventional wire, FIG. 3b is a front perspective view thereof, FIG. 4a is a side view schematically showing a wire of the present invention, and FIG. 4b is a front perspective view thereof. FIG. 5 is a sectional view of the forced lubrication die used in the example of the present invention. 1 ... Supply coil, 2 ... Cleaning process, 3 ... Electroless displacement plating process, 4 ... Cleaning process, 5 ... Drying process, 6 ...
Wet finish wire drawing process, 7 ... Winding coil.

Claims (5)

[Claims] 1. After performing a copper plating treatment on the wire surface,
After washing and drying the wire surface, using a polyhydric alcohol as a solvent, a solution in which a potassium carboxylic acid salt is dissolved, by holding and adhering the carboxylic acid potassium salt on the wire surface, the wire surface per 10 kg of the wire,
A method for producing a wire for gas shielded arc welding, which comprises holding and adhering 0.2 g or more and 10 g or less. 2. A method for holding and adhering a solution of a potassium carboxylic acid salt on the surface of a wire, wherein wet drawing using the solution as a lubricant is used. Of manufacturing wire for gas shielded arc welding of. 3. A wire for gas shielded arc welding according to claim 1 or 2, wherein a forced lubrication die having a nozzle at the inlet of the die is used as the die for wet drawing. Manufacturing method. 4. A gas shielded arc welding wire according to claim 1, wherein electroless displacement plating is used as the copper plating treatment on the wire surface. Method. 5. The wire for gas shielded arc welding according to any one of claims 1 to 4, wherein an inorganic corrosion inhibitor is mixed in a solution of potassium carboxylic acid salt. Production method.