JP2856982B2 - Winding type flux cored wire with good arc stability - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wire feeding property of a flux-cored wire for semi-automatic welding which uses carbon dioxide gas as a shielding gas.

[0002]

2. Description of the Related Art Winding type flux cored wires are manufactured by JI.
Cold rolled steel sheet such as S standard SPCC is 11-13mm wide
A flux is filled in the middle of forming it into a pipe shape using a hoop that has been slit, and after molding, the wire is finished to a wire diameter of 1.2 mm by drawing to obtain a product.

[0003] Products are provided for welding by supplying current to the wires passing through the inside of the cylinder by contact current through a cylindrical copper feed tip. In order for welding to be performed smoothly, it is necessary that the power supply to the wire surface be performed stably and the wire be also fed smoothly. In terms of this surface, a seamless type flux-cored wire which has no opening and whose surface is plated satisfies this condition, but a wound-type flux-cored wire has many problems with this surface.

[0004]

As a lubricant used in drawing, a solid lubricant is often used to enable high-speed drawing. However, if the solid lubricant remains excessively during welding, it increases the electrical resistance of the wire surface and impairs the current flow from the nozzle tip to the wire surface, and is rather harmful to relatively low-speed wire feeding during welding. There are many. Therefore, they are usually removed at the end of drawing. The solid lubricant bites into the wire surface firmly when reducing the surface area by dies or other methods during wire drawing.
Complete removal is quite difficult and irregular residues are unavoidable. As a method of removal, a baking treatment of decomposing and removing by heating to about 350 ° C. in an oxidizing atmosphere;
Alternatively, a method of removing by a degreasing treatment such as washing with an organic solvent such as Freon gas is generally adopted. In any case, in the case of the wound flux cored wire, there is a problem that the lubricant tends to remain in the vicinity of the opening due to the behavior of the material at the time of molding.

[0005] Therefore, for example, Japanese Patent Application Laid-Open No. 50-19629.
No. 5 discloses a method in which lubricating oil is applied only to the central portion of the steel strip surface before forming. In this method, lubrication near the opening is not performed during forming and drawing, and there is a problem that troubles such as seizure are likely to occur during drawing in actual operation. In the baking method, residues that cannot be decomposed and removed after heating usually remain irregularly, and the steel on the surface of the wire is oxidized to form an oxide scale layer, thereby increasing the electric resistance of the wire surface and increasing the wire feeding. There is a problem that the performance is deteriorated.

[0006] In the degreasing method, in addition to the problem that the lubricant cannot be completely removed, the use of a liquid cleaning agent causes the liquid cleaning agent to enter the inside from the seam opening of the wire and remain in the wire. However, there is a problem that during the welding, it is vaporized and defects such as blowholes are generated, and the quality of a welded portion is largely deteriorated. There is also a method of physically removing the solid lubricant by brushing without using a liquid detergent.However, in particular, completely remove the lubricant remaining in the recess near the opening on the wire surface. It is difficult.

SUMMARY OF THE INVENTION The present invention solves the problem of a wire drawing lubricant remaining after drawing in a wire-wound flux-cored wire, and has excellent electric conductivity and feedability, and has a good arc stability. The purpose is to provide.

[0008]

Therefore, according to the present invention, in the lubricant removal by the brushing method which is a physical method, only the lubricant remaining in the vicinity of the seam of the wire is regulated as follows. It has become possible to obtain a wound-type flux cored wire having good arc stability.

[0009] The present invention, arc stability better winding that by physical removal of the area ratio of residual Travel Keru wire drawing lubricant from Sea <br/> arm opening within 0.1mm was 20% or less This is a flux-cored wire. Here, the area ratio of the remaining lubricant is based on the following equation.

[0010]

(Equation 1)

[0011]

As a method of achieving the present invention, the amount of lubricant near the seam in the product diameter can be reduced by polishing the wire surface after forming, for example, as follows. As a polishing method, a forming diameter (4.
2mm), both ends of the opening are 0.35 mm
This is a method of grinding with a width.

According to this method, the product diameter after drawing (1.2 m
In m), the area ratio of the lubricant remaining within 0.1 mm from the seam opening can be reduced to 20% or less. The reason for restricting the seam opening to within 0.1 mm is as follows. As shown in FIG. 1, the ablating flux-cored wire has a shape that is almost a perfect circle before entering the feeding roll (FIG. 1A), but the wire is deformed by the pressing of the roll at the feeding roll portion. (Figure 1
This is because (b)) makes it easier to come into contact with the nozzle tip, and the range is 0.1 mm from the seam opening. Therefore, by regulating the residual area ratio of the lubricant within 0.1 mm from the seam opening, the electric resistance on the wire surface is not increased, the electric conductivity is improved, and the residual lubricant acts appropriately to feed the wire. The feedability is improved, and the stability of the arc during welding is greatly improved as compared with a conventional baking-type wound flux cored wire.

[0013]

FIG. 2 shows the relationship between the residual area fraction of lubricant within 0.1 mm from the seam opening and the welding arc instability as a combined result of wire feed and energizing performance. It is the result which illustrated the experimental result obtained. Table 1 shows the adopted welding machines and welding conditions.

[0014]

[Table 1]

If the area ratio of the lubricant remaining exceeds 20%, the electric conductivity from the power supply tip to the wire is deteriorated during welding, the wire feedability is extremely deteriorated, and the arc is extinguished instantaneously. Unstable phenomena occur frequently, making good welding impossible.

[0016]

As described above, according to the present invention, the area ratio of the lubricant remaining within 0.1 mm from the seam opening of the flux-wound flux-cored wire is restricted to 20% or less, so that the winding having good wire feeding property can be obtained. It was possible to obtain a flux cored wire with a clamp.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a wound-type flux-cored wire.

FIG. 2 is a characteristic diagram showing an influence of a residual area ratio of a lubricant on arc stability.

Claims (1)

(57) [Claims] 1. The method of claim 1, wherein the physical removal removes 0.1 mm from the seam opening.
The remaining area ratio of your Keru wire drawing lubricant within 1mm 20
% Or less , and a flux-cored wire with excellent arc stability.