JPH04371392A - Production of wire including flux for welding - Google Patents

Abstract

PURPOSE:To omit baking of a wire including flux for welding by specifying forming, wire drawing and finish wire drawing in a steel hoop. CONSTITUTION:After sealing the flux by bend-forming the steel hoop as an outer shell, the wire drawing at intermediate step is executed with a roller dies and after that, the finish wire drawing is executed with a hole die. By this method, at the time of manufacturing the wire including the flux for welding, invasion of lubricator into inner part of the wire from gap of seam part can be prevented and also, the baking and brushing can be omitted.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a method for manufacturing flux-cored wire for welding, and in particular, a tightening method in which flux is encapsulated in the process of bending and forming a steel hoop, and then the wire is drawn. The present invention relates to a method of manufacturing a flux-cored wire for welding.

0002

[Prior Art] A method for manufacturing flux-cored wire using the seaming method includes the following steps as shown in Figure 2: (1)
A steel band hoop (hereinafter simply referred to as hoop) with a thickness of 0.8 to 1.0 mm and a width of 10 to 15 mm is formed into a U by a forming roller.
Bend and form into a letter shape.

(2) 10 to 20% (weight %) of flux is added to the U-shaped hoop. (3) The U-shaped hoop to which flux has been added is further bent into an O-shape using a forming roller. The process up to this point has been a bending process, and since the forming process in this process uses rollers, no lubricant is used.

(4) A material filled with flux and bent into an O shape (hereinafter referred to as wire) is cut into a predetermined intermediate diameter, for example 3.0 to 2.0 mm, using a hole die.
Apply lubricant to 0 mmφ and draw the wire. After that, as shown in FIG. 2, there are cases where the process is performed in the A process and cases where the process is performed in the B process.

First, in step A, (5) the wire is baked at a furnace temperature of 300 to 400° C. in order to incinerate and remove the lubricant used in wire drawing up to the intermediate stage. However, if an inorganic lubricant is used, brushing is performed instead of baking, but the following explanation will focus on baking.

(6) The desired final diameter of the wire after baking, for example 1.6 mm, 1.4 mm,
Finish wire drawing is carried out to 1.2 mm while applying lubricant using a hole die. (7) After finishing wire drawing, rewinding is performed to spool winding, bail winding, etc. When rewinding, apply lubricating oil if necessary so as not to interfere with wire feeding during welding work.

On the other hand, in step B, (8) the wire drawn to the intermediate stage is further subjected to finishing wire drawing using a hole die in the same manner as in the above (6). (9) After finishing wire drawing, the wire that has reached the diameter of the product is baked and the lubricant is removed by incineration.

(10) Next, lubricating oil is applied for welding work and the like. The application of lubricating oil in this case is essential to maintain lubricity during wire feeding, since the wire has been baked to the diameter of the product. After that, the winding is changed to spool winding, pale winding, etc. as in step A. In addition, Figure 2
The selection of the A process and the B process shown in the figure is made depending on the purpose of use of the wire, the material of the hoop, the drawing speed for finishing wire drawing, etc.

[0009] In the above-mentioned baking, the joint (seam) of the wire after O-shaped bending shown in item (3) opens due to springback and a gap is created, so the lubricant used during wire drawing with the hole die is The lubricant penetrates into the inside of the wire and causes a lot of spatter during welding. Therefore, not only the lubricant adhering to the surface of the wire but also the lubricant that has penetrated into the wire should be incinerated and removed in advance.

0010

The cross-sectional shape of the wire after the above-mentioned O-shaped bending is shown in FIG. The one shown in (A) of this figure is an abutting type wire, and (B)
The wires shown in FIG. 1 are overlapping type wires, and each wire 1 has an O-shaped outer sheath (hoop) 2 filled and sealed with flux 3.

In this state, a gap 4 due to springback remains at the seam after the hoop serving as the outer skin 2 is bent into an O shape due to its rigidity. Baking is required because the lubricant used in the intermediate stage of wire drawing enters through this gap 4. Therefore, not only is baking equipment required, but also time and energy losses are unavoidable.

[0012] In addition, as in the technique disclosed in Japanese Patent Application Laid-open No. 63-299886, in order to prevent flux from spilling from the seam and the above-mentioned lubricant from entering,
Although there are some methods that limit the overlap dimension of this seam part, there is inevitably a gap due to springback immediately after O-bending, and the lubricant infiltrates through this gap during the initial pass of wire drawing, so This cannot be said to be a sufficient measure to eliminate baking.

[0013] The present invention provides a manufacturing method for welding flux-cored wire using a crimp method, which eliminates baking and brushing of the wire, reduces equipment costs, shortens processing time, and prevents energy loss. The purpose is to

[0014]

[Means for Solving the Problems] The method of manufacturing a flux-cored wire for welding according to the present invention involves bending and forming a steel strip hoop serving as an outer skin to encapsulate flux, and then drawing the wire in an intermediate stage using a roller die. The above-mentioned problems of the conventional technology are solved by performing finishing wire drawing using a hole die after that.

[0015]

[Function] In manufacturing flux-cored wire for welding, the process from bending the hoop into an O-shape to encapsulating flux is no different from the conventional method. After that, in the manufacturing method of the present invention, an intermediate step of wire drawing is performed using a roller die instead of the conventional wire drawing using a hole die.

When using a roller die, unlike when using a hole die, no lubricant is required. Therefore, even if there is a gap in the wire after O-shaped bending, there is no possibility that the lubricant will infiltrate through this gap. Even if a lubricant is then applied and finishing wire drawing is performed, the lubricant will not enter the inside because the gap is completely closed by the wire drawing by the roller die in the intermediate stage.

As described above, in the method for manufacturing a welding flux-cored wire according to the present invention, it is possible to completely prevent lubricant from entering the inside during the manufacturing process, so baking and brushing can be omitted.

[0018]

[Example] Fig. 1 is a drawing for explaining the process of manufacturing a flux-cored wire for welding according to the present invention. As mentioned above, there is no such thing. Following this bending process, in the present invention, (20) 1 to 4 passes of wire drawing are performed using a roller die;
Perform a reduction of the wire to an intermediate stage diameter. Of course, no lubricant is used in this case.

(21) The wire drawn up to the intermediate stage with a roller die is coated with a lubricant and then finished drawn with a hole die. The lubricant in this case is preferably inorganic, such as molybdenum disulfide or graphite. (22) After finishing the wire drawing, the wire is re-wound to spool winding, pale winding, etc. in the same manner as before. At this time, apply lubricating oil if necessary.

[0020] The thickness is 0.8 by the above-mentioned manufacturing method of the present invention.
A welding flux-cored wire with a diameter of 1.2 mm was manufactured from a hoop with a width of 15 mm. First, 15% (weight%) is applied to the hoop, which is bent into a U-shape using a forming roller.
After adding the flux, O
It was bent into a mold to obtain a wire with a diameter of 4 mm.

[0021] After that, the wire encapsulated with flux was reduced in area in three passes using a cassette roller die (CRD) to a diameter of 3.0 mm (4.0 mmφ → 3.6 mm).
An intermediate stage of wire drawing was performed to φ→3.3 mmφ→3.0 mmφ). Then, using 8 hole dies from an intermediate stage wire with a diameter of 3.0 mm, the target product diameter was 1.2.
Wire drawing was performed up to mm. In this case, the lubricant used was mainly inorganic.

Subsequently, this wire was wound into a 20 kg spool winding and a 300 kg pale winding without applying lubricating oil. The welding flux-cored wire manufactured in this way was used for carbon dioxide shielded arc welding, but the generation of spatter was no different from that of the conventional method, and it is clear that when the present invention is implemented, the same quality as that of the conventional method can be obtained. Understood.

The present invention can be applied to either the abutting type or overlapping type welding flux-cored wire shown in FIG. Further, the diameter of the wire after wire drawing with the roller die shown in item (20) of FIG. 1 is determined by taking into consideration the conditions of the final wire drawing on the condition that at least the gap in the seam portion is closed.

[0024]

Effects of the Invention According to the method of manufacturing a flux-cored wire for welding of the present invention, a wire bent into an O-shape is drawn with a roller die to close the gap at the seam, and then finished wire is drawn with a hole die. Therefore, it is possible to completely prevent lubricant from entering through the seam, making it possible to omit baking and brushing. Therefore, these facilities become unnecessary, processing time and energy loss due to them are suppressed, and a tremendous economical effect can be obtained.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of processing steps of a method for manufacturing a flux-cored wire for welding according to the present invention.

FIG. 2 is an explanatory diagram of processing steps in a conventional manufacturing method.

FIG. 3 is an explanatory view of a cross section of a wire after a steel band hoop is bent into an O shape.

[Explanation of symbols]

1 Flux-cored wire 2. Outer skin 3 Flux 4 Gap

Claims (1)

[Claims] 1. A method for producing a flux-cored wire for welding, comprising: bending and forming a steel strip hoop serving as an outer skin to encapsulate flux; then drawing the wire in an intermediate stage using a roller die; 1. A method for producing a flux-cored wire for welding, the method comprising finishing wire drawing.