JP2000140975A - Manufacture of deformed bar - Google Patents

Abstract

PROBLEM TO BE SOLVED: To continuously manufacture a deformed bar large in lift thickness ratio, and to improve the productivity, the quality and the energy saving by effecting a series of processes in line in which a metallic bar-like body is continuously cast from a molten metal, the hot multiple-rolling is effected to obtain a roughly deformed bar, the bar is trimmed to a specified width, and cold rolled to obtain the specified deformed bar, and the bar is wound. SOLUTION: A roughly deformed bar is preferably rolled by a pair of rolls one side of which is a roll provided with a groove or a ridge, and the other side of which is a flat roll. A copper alloy rod-like body 4 which is cast by feeding a molten metal 2 from an induction heating type melting furnace 1 to a continuous casting machine 3, is hot rolled by a hot multiple rolling mill 5 for roughly forming a deformed bar. The roughly deformed bar 6 cooled in a water tank 7 is pickled to remove a surface oxide layer, and after cleaning with water, the bar is passed through a trimming device 9 to be trimmed to a specified width. The roughly deformed bar 6 is wound as a deformed bar 11 of the specified dimension by a finish cold groove rolling machine 10. The roughly deformed bar large in thickness ratio is formed by the hot multiple rolling mill to realize the in-line operation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a profiled strip, and more particularly to a method for manufacturing a profiled strip suitable for a lead frame material for a power transistor.

[0002]

2. Description of the Related Art Generally, a power transistor is required to have good heat radiation. Therefore, as a lead frame material for a power transistor, an odd-shaped section having a thick portion having good heat dissipation and a thin portion serving as a lead portion is used.

Heretofore, this irregular cross section has been manufactured mainly by the following two methods.

(1) Roll rolling method This roll rolling method is manufactured through the following steps.

[0005] First, a metal component such as a copper alloy as a raw material is heated and melted, and then an ingot is manufactured through a casting process. The shape of the ingot is generally a rod-like body or a square body.

[0006] The ingot is hot-rolled by hot rolling to be flat-rolled.

The oxide scale generated on the surface of the flat strip is removed by chamfering.

[0008] The flat strip from which the oxide scale has been removed is subjected to preliminary cold rolling.

[0009] The pre-cold-rolled flat strip is cold-rolled into a profiled strip by a roll provided with grooves or peaks.

[0010] The cold-rolled deformed strip is annealed.

[0011] The oxide scale generated on the surface of the annealed strip is removed by grinding.

By repeating the above steps (1) to (4), a desired irregularly shaped cross section is manufactured.

(2) Press working method In this working method, a metal strip having a predetermined thickness is pressed to produce a deformed cross section.

Among these, the roll rolling method (1) has high productivity, whereas the press working method (2) has low productivity. For this reason, the deformed cross section is mainly manufactured by a roll rolling method.

[0015]

However, in the roll rolling method of the above (1), a heating step is performed when hot rolling an ingot obtained by melting and casting, and further, “cold rolling →
It is necessary to repeat the process of “annealing → oxide scale facing” a plurality of times, and as a result, their productivity is low.

On the other hand, in recent irregular-shaped cross-sections, it is required that the thickness ratio between the thick portion and the thin portion is large. However, in the roll rolling method of the above (1), since the deformed cross section is formed by cold rolling, when rolling a deformed cross section having a large thickness ratio between the thick portion and the thin portion, the rolling conditions become severe, and the rolling condition becomes severe. As a result, it was difficult to manufacture a deformed cross-section having a large thickness ratio between the thick portion and the thin portion.

The present invention has been made in view of such a point, and an object of the present invention is to solve the above-mentioned drawbacks of the prior art and to provide a modified cross-section having a large thickness ratio between a thick portion and a thin portion. An object of the present invention is to provide a method for producing a deformed cross-section strip which can be continuously manufactured in-line even if it is a strip, and as a result, productivity, quality and energy saving of the deformed cross-section strip can be remarkably improved.

[0018]

The gist of the present invention is that a molten metal is continuously fed into a continuous casting machine to continuously cast a metal rod, and then the metal rod is hot-pressed. Hot-rolled by a multi-high rolling mill so as to obtain a rough formed irregular cross section,
Next, cooling, pickling, and washing the rough-formed irregular cross-section strip, then trimming the washed rough-formed irregular cross-section strip to a predetermined width, and then finishing the cross-section with a predetermined shape and dimensions by a finishing cold groove rolling mill. A method for producing a deformed cross-sectional strip characterized by continuously performing in-line a series of working steps of cold rolling into a strip and then winding the deformed cross-section strip by a winder.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of a method for manufacturing a profiled strip according to the present invention will be described with reference to the drawings.

(First Embodiment) FIG. 1 is a front explanatory view showing a first embodiment of a method for manufacturing a profiled strip according to the present invention.

In FIG. 1, 1 is a high frequency induction type melting furnace,
2 is a molten metal obtained by melting a copper alloy in the melting furnace 1; 3 is a continuous caster; 4 is a cast copper alloy rod;
This is a hot multi-high rolling mill having a pair of rolls for rough forming of irregular cross-section, where 51 is a first-stage roll, 52 is a second-stage roll,
3 is a third-stage roll, 6 is a roughly-formed irregularly shaped cross section, 7 is a water tank,
8 is a pickling / water washing tank, 9 is a trimming device, 10 is a finish cold groove rolling mill, 11 is a profiled strip, and 12 is a winding machine.

As can be seen from FIG. 1, in the first embodiment of the method for manufacturing a profiled strip according to the present invention, first, a molten metal 2 is continuously supplied from a high-frequency induction type melting furnace 1 to a continuous caster 3. A copper alloy rod 4 having an outer diameter of 50 mm is continuously cast.

Next, the surface temperature of the continuous casting is 790 ° C.
Is sent to a hot multi-stage rolling mill 5 for rough forming of a deformed cross-section and hot-rolled to have a rough-formed deformed cross section.

Next, the roughly formed irregularly shaped cross section strip 6 obtained by the hot rolling is cooled by passing through a water tank 7.

Next, the cooled roughly formed irregularly shaped section 6
Is passed through a pickling / water washing tank 8 to remove the surface oxide layer by pickling, and then washed with water. Here, the pickling / water washing tank 8 is divided into a pickling tank and a water washing tank, and dilute sulfuric acid is used as the acid in the pickling tank.

Next, the water-washed rough-shaped irregularly shaped section 6 is trimmed to a specified width, for example, 65 mm by passing through a trimming device 9.

Next, the rough-formed irregular-shaped section 6 trimmed to the specified width is passed through a finishing cold groove rolling mill 10 to be cold-rolled into an irregular-shaped section 11 having a predetermined shape and a predetermined dimension.

Next, the cold-rolled deformed section strip 11 is wound up by a winder 12.

In the method of manufacturing a deformed cross section according to the first embodiment, since a series of steps are continuously performed in-line, productivity, quality and energy saving of the deformed cross section can be remarkably improved.

(Second Embodiment) FIG. 2 is an explanatory front view showing a second embodiment of the method for manufacturing a modified cross-section strip according to the present invention.

In FIG. 2, 1 is a high-frequency induction melting furnace,
2 is a molten metal obtained by melting a copper alloy in the melting furnace 1; 3 is a continuous caster; 4 is a cast copper alloy rod;
This is a hot multi-high rolling mill having a pair of rolls for rough forming of irregular cross-section, where 51 is a first-stage roll, 52 is a second-stage roll, 5
3 is a third-stage roll, 54 is a fourth-stage roll, 55 is a fifth-stage roll, 6 is a roughly-formed irregularly shaped cross-section, 7 is a water tank, and 8 is pickling / washing.
A washing tank, 9 is a trimming device, 10 is a finishing cold groove rolling mill, 11 is a profiled strip, 12 is a winding machine, and 13 is a gutter.

That is, as can be seen from FIG. 2, in the second embodiment of the method for manufacturing a profiled cross section of the present invention, first, the molten metal 2 is continuously fed from the high frequency induction type melting furnace 1 to the continuous casting machine 3 via the gutter 13. By continuously supplying, a copper alloy rod 4 having an outer diameter of 50 mm (the rod has an elliptical cross section) is continuously cast.

Next, the surface temperature of the continuous casting is 790 ° C.
The copper alloy rod-shaped body 4 is hot-rolled by a hot multi-stage rolling mill 5 for rough forming of a deformed cross section so as to have a rough-formed deformed cross section.

FIG. 3 is an explanatory sectional view showing the shape of rolls in each stage of the hot multi-high rolling mill 5 and the shape change of a copper alloy rod which is hot-rolled by these rolls.

In FIG. 3, reference numeral 51 denotes a first-stage roll;
Is a second-stage roll, 53 is a third-stage roll, 54 is a fourth-stage roll, 55 is a fifth-stage roll, and 6 is a roughly-formed irregularly shaped cross section.

As can be seen from FIG. 3, in the hot multi-high rolling mill 5 composed of five pairs of rolls, the rolls from the first stage to the third stage are grooved rolls, The fifth stage roll has a grooved roll on one side and a flat roll on the other side. Then, the copper alloy rods 4 are successively rolled into the roughly-formed irregularly shaped cross-section strips 6 by sequentially passing through these five-stage rolls.

Next, the coarsely shaped irregularly shaped section 6 hot-rolled to the roughly shaped irregularly shaped section is cooled by passing through a water tank 7, and the cooled roughly shaped irregularly shaped section 6 is pickled and washed with water. 8 and pickling to remove the surface oxide layer. Here, dilute sulfuric acid was used as the acid in the pickling tank. The pickling / water washing tank 8 is divided into an acid washing tank and a water washing tank.

Next, the pickled and roughly formed irregularly shaped cross section 6 is washed with water on the subsequent side of the pickling / washing tank 8.

Next, the water-washed rough-formed irregularly shaped section 6 is trimmed to a specified width, for example, 65 mm by passing through a trimming device 9.

Next, the rough-shaped irregularly shaped section 6 trimmed to the specified width is passed through a finishing cold groove rolling mill 10 to be cold-rolled into an irregularly shaped section strip 11 having a predetermined shape and a predetermined dimension.

Next, the irregularly shaped cross-section strip 11 thus cold-rolled into a predetermined shape and a predetermined size is wound around a winder 12.

FIG. 4 is an enlarged perspective view of the deformed cross-section strip 11 thus obtained, which has been cold-rolled into a predetermined shape and a predetermined size.

In the method of manufacturing a deformed cross-section strip according to the second embodiment, a series of steps are continuously performed in-line and the first step is performed.
Since the casting and hot rolling steps are made more efficient than in the embodiment, the productivity, quality and energy saving of the deformed strip can be further improved.

In the present invention, the casting method of the continuous casting machine 3 is not particularly limited, and may be any of a vertical type, a horizontal type, and another type.

In the present invention, the copper alloy rod 4 preferably has an outer diameter of 100 mm or less. Further, it is desirable that the copper alloy prismatic body has a sectional area of 10,000 mm ² or less. This is because, in the case of the copper alloy rod 4 having an outer diameter of 100 mm or more or the copper alloy square having a cross-sectional area of 10,000 mm ² or more, the number of hot rolling rolls for roughly forming into a predetermined size and shape must be increased. This is because, as a result, the temperature of the material during hot rolling decreases, making hot rolling difficult.

In the present invention, it is necessary that the hot multi-high rolling mill 5 includes at least two pairs of rolls.
This is because rolling with only a pair of rolls results in a small amount of processing, and as a result, it is impossible to completely roll a specially shaped cross section, particularly a thick portion at the center in the width direction and a thin portion at both ends in the width direction.

Here, the rolls used in the hot multi-high rolling mill 5 are as follows: the rolls in the initial stage of rolling are rolls of a combination of rolls provided with grooves or ridges on one side, and the rolls in the middle stage to late stage of rolling are grooves on one side. Alternatively, it is desirable that the pair of rolls include a roll provided with peaks and a flat roll on the other side. This is to enable the copper alloy rod 4 to be hot-rolled stepwise into a roughly formed irregular cross-sectional shape.

In the present invention, the finishing cold groove rolling mill 10
The number of roll stages is not particularly limited.

In the present invention, there is no limitation on the number of peaks or grooves, the width of the metal strip, the thickness ratio of the thick part and the thin part, and the like.

[0050]

According to the method for producing a deformed cross section of the present invention, the deformed cross section can be continuously produced in-line, and as a result, productivity, quality and energy saving of the deformed cross section can be remarkably improved. Yes, industrially useful.

[Brief description of the drawings]

FIG. 1 is an explanatory front view showing a first embodiment of a method for manufacturing a modified cross-section strip according to the present invention.

FIG. 2 is an explanatory front view showing a second embodiment of the method for manufacturing a modified cross-section strip according to the present invention.

FIG. 3 shows the roll shape of each stage of a rough-formed deformed section hot multi-high rolling mill used in a second embodiment of the method for producing a deformed section strip according to the present invention and a copper alloy rod hot-rolled by these rolls. FIG. 3 is an explanatory cross-sectional view showing a shape change.

FIG. 4 is an enlarged perspective view of a deformed cross-section strip cold-rolled to a predetermined shape and a predetermined size according to a second embodiment of the method for manufacturing a deformed cross-section strip of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 high frequency induction type melting furnace 2 molten metal 3 continuous caster 4 copper alloy rod 5 hot multi-stage rolling mill 51 first stage roll 52 second stage roll 53 third stage roll 54 fourth stage roll 55 fifth stage roll 6 coarse Formed profiled cross section 7 Water tank 8 Pickling / washing tank 9 Trimming device 10 Finish cold groove rolling mill 11 Deformed cross section 12 Winding machine 13 Gutter

Claims (5)

[Claims] 1. A metal rod is continuously fed into a continuous casting machine to continuously cast a metal rod, and then the metal rod is formed into a roughly formed irregular cross section by a hot multi-stage rolling mill. Hot rolling, then cooling, pickling and washing the rough formed irregular cross-section strip, then trimming the washed rough formed cross-section strip to a predetermined width, and then finishing to a predetermined shape with a cold groove mill. A method for producing a profiled section, comprising: performing a series of working steps in a continuous manner in-line by cold rolling to a profiled section having the same shape and dimensions, and then winding the profiled section by a winder. 2. The method according to claim 1, wherein the molten metal is fed into the continuous casting machine through an inclined gutter. 3. The hot rolling of a metal rod is carried out by first roughly rolling the metal rod into a primary compact with a pair of rolls comprising grooved rolls, and then rolling the roll on one side with grooves or peaks. ,
2. The method according to claim 1, wherein the other side is rolled by a pair of rolls comprising a flat roll into a roughly formed cross section. 4. The method according to claim 1, wherein the metal rod has an outer diameter of 100 mm or less. 5. The method according to claim 1, wherein the metal rod is a square body having a sectional area of 10,000 mm ² or less.