JPH0211298A - Forming of duplex flux-cored wire - Google Patents

Abstract

PURPOSE:To obtain a duplex type flux-cored wire whose cross sectional shape is symmetrical by deforming a U-shape gutter-like bottom plate to a mountain shape and forming it to roughly a W-shape gutter shape at the time of forming a flux filling body having a circular cross section after having formed a flux filling body having a rectangular cross section by bending band steel like a U-shape gutter. CONSTITUTION:An outer flux filling body having a rectangular cross section is formed by bending band steel like a U-shape gutter and supplying an outer flux to the inside of its U-shape, and thereafter, the filling body is formed to a U-shaped body and an inner flux is supplied to the inside of its U-shape, and thereafter, the filling body is formed to a circular cross section, and at the time of forming a duplex type flux- cored wire, band steel is formed like a U-shape gutter, and thereafter, the center of the bottom plate is deformed and worked to a mountain shape, an outer flux is supplied, and when the upper face of its flux s flattened, a charging distribution of the flux is abundant on the right and the left of a hoop, and also, the flux can be charged uniformly on the right and the left of the hoop. In such a way, when the wire is manufactured after the outer flux is charged, the cross section of the wire is symmetrical and becomes a concentric circle, the welding workability is satisfactory, and the wire scarcely having a welding defect can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a method for manufacturing a double flux-cored welding wire.

<Prior Art> As shown in Japanese Patent Publication No. 44-2336, a double-flanked wire has been well known, and a method of forming this wire according to the prior art is shown in the fourth column.

That is, hoop l is a−+ b −+ (→d −+
The molding is performed in the order of 6...j, and the outer flux 2 is charged between steps C and d, and the inner flux 3 is charged between steps 1 and 2. The process of forming a flux-cored wire with a layered cross-sectional structure is completed. Thereafter, the wire is cold drawn to a predetermined wire diameter using a wire drawing machine to become a product.

Figure 5 shows an enlarged view of the charging section for the outer flux 2.
Normally, flux is charged into the hoop using a quantitative feeder so that the inclusion ratio is constant, but the flux distribution inside the hoop varies depending on the physical properties such as the bulk density, particle size, composition, and wetness of the flux. It changes and is not uniform. For this reason, as shown in Fig. 5, chopper 4 is used to make the distribution uniform, but as the line speed increases, the flux may fly off, the hoop may vibrate, tears may occur, and the distribution may be uneven. It becomes a flux distribution. If roll forming is performed in this state, the cross section of the wire at the completed forming stage corresponding to j in Fig. 4 will have uneven flux in the vicinity of the hoop seam, so the cross section of the wire will be as shown in Fig. 6. This results in a loss of compatibility with the welding process, and the arc is unevenly generated due to uneven flux, and unmelted flux protrudes, which impairs welding workability and causes vertical welding defects. As shown in FIG. 6a, a normal cross-section of the wire is symmetrical and concentric circles, with the surrounding flux being sufficiently filled in the vicinity of the hoop seam.

<Problems to be Solved by the Invention> As mentioned above, according to the conventional method for forming a double type flux-cored wire, the cross section of the wire becomes asymmetrical and non-concentric due to the non-uniform flux distribution within the hoop.
This impairs welding workability and causes welding IB defects. The present invention has been made in order to provide a method for forming a double-flanked wire in which the flux in the vicinity of the hoop seam is forcibly secured, and the cross-section of the wire is symmetrical and concentric.

<Means for Solving the Problems> The present invention involves continuously bending a steel strip into a gutter-like shape, supplying outer flux to the U-shaped inside of the gutter-shaped steel strip, and bending the steel strip into a gutter-shaped steel strip. The first step is to bend both edge portions inward and stack them to form an external flux filling body with a rectangular cross section.Bend the nuclear external flux filling body into a mouth-shaped gutter shape and encapsulate it inside the U-shape of the ■-shaped gutter-like filling body. In a continuous forming method for a double-flanked welding wire, the method comprises: a second step of supplying flux, then a third step of tightening and forming a J-shaped trough-like filling body into a circular cross section and incorporating the embedded flux in the center. , after forming the steel strip into a gutter shape in the first step,
This is a method for forming a double flux-cored wire in which the central part of the bottom plate is deformed into a chevron shape and formed into the same shape as a gutter.

<Operation> Continuously bending the steel strip into a gutter shape, supplying the outer flux to the inner side of the gutter-shaped steel strip to form an outer flux-filled body with a rectangular cross section, and making the filling body into a U-shape. In order to supply the internal flux to the inside, the filling body is formed into a circular cross section and a wire is injected with double flux.The steel strip is bent into a gutter shape and the cross section is formed into a gutter shape, and then the center of the bottom plate is formed into a chevron shape. When deforming and processing the outer envelope flux and making the upper surface of the flux flat, the flux distribution is large on the left and right sides of the hoop, and the flux can be charged evenly on the left and right sides of the hoop.

After charging the outer flux in this way, if a wire is manufactured using the same continuous forming method as in the past, the cross section of the wire will be symmetrical and concentric, and a wire with good welding workability (and fewer welding defects) will be manufactured.

<Example> Fig. 1 shows a wire manufacturing process diagram according to the present invention, but after Fig. 4C of the conventional wire manufacturing process (see Fig. 4),
A step of deforming and processing the center portion of the bottom plate of the gutter-like hoop into a chevron shape is included, and a step of making the distribution of flux uniform using the chipper shown in FIG. 4d is omitted. Here, the hoop is formed into a gutter shape by roll forming as shown in FIG. In other words, the hoop consists of an upper roll 5 and a lower roll 6.
It is roll formed into a mouth-shaped trough-like cross section as shown in FIG. 1C and FIG. 4C. Next, modifications according to the present invention.

As shown in Fig. 2, when roll forming is performed using upper and lower rolls in which the center part of the upper roll 7 has a reverse circular shape and the center part of the normal roll 8 has a convex shape, the hoop l is 1
It has a circular cross-sectional shape as shown in Figure d. When the outer envelope flux is supplied to the inside of this hoop with a circular cross section, the flux can be distributed in a large amount on the left and right sides of the hoop, and can be charged evenly on the left and right sides.

As a hoop, J￥mi 0.18mm, Ill 2
Using 5pcc material with a size of 0mm, the inclusion ratio is 15fflfff% for the outer flux, and 13% for the inner flux.
In the manufacturing process of a two-layer cross-section flanked rewire having a wire diameter of 3.2 mmφ after completion of fffffi%5 molding, the hoop shape, especially only the hoop bottom plate, was molded as shown in FIG. 3 to manufacture the product. As a result, concentricity was significantly improved and welding workability became stable.

<Effects of the Invention> According to the method of the present invention, it is possible to stably produce a bi-electromagnetic flux-cored wire having a symmetrical and concentric cross-sectional shape, which stabilizes welding workability and prevents the occurrence of welding defects. I can do it.

[Brief explanation of the drawing]

FIG. 1 is a wire manufacturing process diagram according to the present invention, and FIG. 2 is a diagram of the wire manufacturing process according to the present invention.
3 is a cross-sectional view of the hoop in FIG. 1d, FIG. 4 is a conventional wire manufacturing process diagram, and FIG. 5 is an enlarged view of FIG. 4d, FIG. 6 is a cross-sectional view of a double flux cored wire. 2...Outer packaging flux, 4...Chinba 6...lower roll, 8...lower roll. 3... Inclusion fluff, 5... Top roll, 7... Top roll, ■... Hoop (or steel band),

Claims (1)

[Claims] A steel strip is continuously bent into a ■-shaped trough-like shape, an outer flux is supplied to the inside of the ■-shaped trough-like steel strip, and both edge portions of the ■-shaped trough-like steel strip are bent inside. A first step of bending the outer flux filling body into a U-shaped gutter shape and supplying the inner flux to the U-shaped inside of the U-shaped gutter-shaped filling body. 2nd step: Next, the U-shaped gutter-like filling body is tightened and formed into a circular cross section,
A method for continuously forming a double flux-cored welding wire, which comprises: a third step of incorporating embedded flux in the center; after forming the steel strip into a U-shaped gutter shape in the first step;
A method for forming a double type flux-cored wire, which is characterized by deforming the center part of the bottom plate into a chevron shape and forming it into a ■-shaped gutter shape.