JP2734040B2 - Rough rolling method for non-ferrous metals - Google Patents

Description

The present invention relates to a method for rough rolling of non-ferrous metals.

[Prior Art] A conventional non-ferrous metal rough rolling method will be described with reference to FIG.

Edger 1 for width reduction in order from upstream in the line direction
And a reversible rough rolling mill 2 and a shear 3 for cutting.

A slab is cast by pouring a molten metal of a non-ferrous metal such as aluminum or copper into a mold (not shown), and the slab is roughly rolled by a rough rolling device shown in FIG.

That is, the non-ferrous metal slab a is first passed through the edger 1 to reduce the width, and then the slab a is passed once by the rough rolling mill 2 to reduce the thickness, or is reciprocated a plurality of times to reduce the thickness. The so-called reverse rolling is carried out to finish it to a predetermined thickness while appropriately performing edging. Finally, a defective shape portion at the front and rear ends of the slab a, that is, a crop portion is cut by the shear 3.

[Problems to be Solved by the Invention] However, in the above-mentioned conventional method for rough rolling of non-ferrous metal, the width of the slab a is reduced by the edger 1, and thus the following problems occur.

Since the edger 1 cannot greatly reduce the width of the slab a, the width of the slab a after the rough rolling is substantially determined from the width of the slab a before the rough rolling. In order to make the width dimension, it is necessary to easily make a large number of molds having different width dimensions at a fine pitch so that the slabs a having different width dimensions can be properly used.

Therefore, in order to separately produce the slabs a having different widths, the mold must be replaced frequently, which requires much labor and time, and the overall rough rolling efficiency for the nonferrous metal slab a is low.

The extension of the slab a in the line direction by the edger 1 is larger at the width end than at the width center.
A fish tail c having a poor shape is formed at the front and rear ends of the fish roll, and the fish tail c tends to become large due to the thickness reduction in the rough rolling mill 2; It grew and the yield was bad.

The slab a receives the tensile force b in the line direction from the edger 1 as shown in FIG.
Since a tensile stress in the line direction is generated inside, and the center porosity formed inside at the time of casting by the mold, that is, the hollow portion is left without being crushed,
Internal quality was not good.

The rough rolling method for non-ferrous metals of the present invention aims to solve the above-mentioned problems.

[Means for Solving the Problems] The present invention prepares equipment capable of arbitrarily performing a width reduction step by a width reduction press and a thickness reduction step by a rough rolling mill on a non-ferrous metal slab, When passing a thin slab, and when passing a slab having a medium hardness and width, perform the width reduction process with a width reduction press first, and then perform the thickness reduction process once with a rough rolling mill once. As described above, when a hard and thick slab is to be passed, the thickness reduction step by a rough rolling mill is performed at least once, and the width reduction step by a width reduction press is performed later. The present invention relates to a method for rough rolling of non-ferrous metal, characterized in that slabs of various widths can be arbitrarily obtained by repeating the above according to the method.

[Operation] By using the width reduction press, the width reduction amount for the non-ferrous metal slab can be increased, so that the number of required molds can be reduced, and the labor and time for replacing the molds can be reduced. Since it can be reduced, the efficiency of rough rolling can be increased.

Also, since the width reduction press applies a compressive force in the line direction to the non-ferrous metal slab, the generation of fish tail is suppressed by the compressive force, and the crop amount at the rear end of the slab is reduced, so that the yield can be improved. Furthermore, the generation of tensile stress in the line direction inside the slab is prevented by the compressive force, and the center porosity is compressed to improve the internal quality of the slab.

Furthermore, the width reduction step and the thickness reduction step for the non-ferrous metal slab are alternately performed at least once, thereby reducing the width reduction force by performing the thickness reduction first and then performing the width reduction. If the width reduction is performed in a plurality of times, the width reduction force per operation can be reduced, and the pressing ability of the width reduction press can be reduced.

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings.

 FIG. 1 is an example of an apparatus for implementing the method of the present invention.

In order from the upstream in the line direction, a reversible width reduction press 8 that has dies 6 and 7 with different directions of the tapered portions 4 and 5 in two upper and lower stages to enable switching use of the dies 6 and 7, An edger 9 for cutting, a reversible rough rolling mill 10 and a shear 11 for cutting are provided.

Reference numeral 12 denotes a buckling prevention roller provided on the width reduction press 8.

When the slab a of a non-ferrous metal such as aluminum or copper to be rough-rolled is soft and thin, the slab a was first passed through a width reduction press 8 to reduce the width, as shown in FIG. Thereafter, only when necessary, the squareness of the slab a is determined by the edger 9 (the same applies hereinafter), and the slab a is rough-rolled.
After passing through once with 10, the thickness is reduced to a predetermined thickness, and finally, the defective shape portion at the rear end of the slab a, that is, the crop portion is cut by the shear 11.

When the slab a of the non-ferrous metal to be rough-rolled has a medium hardness and a medium thickness, as shown in FIG. The step of reducing the thickness by 10 is so-called reverse rolling in which the thickness is reduced while reciprocating the slab a a plurality of times.

Further, when the slab a of the non-ferrous metal to be rough-rolled is hard and thick, as shown in FIG. 2 (c), the slab a is first passed through the rough rolling mill 10 to reduce the thickness by reverse rolling. Is performed, the width is reduced by passing through the width reduction press 8, the thickness is reduced by reverse rolling through the rough rolling mill 10, and the width is reduced again by passing through the width reduction press 8, If necessary, the step of reducing the thickness by the rough rolling mill 10 and the step of reducing the width by the width reducing press 8 are alternately repeated. Finally, the defective shape portion at the front and rear ends of the slab a, that is, the crop portion is cut by the shear 11.

When the hardness or thickness of the non-ferrous metal slab a to be roughly rolled is other than the above, the width reduction process by the width reduction press 8 and the thickness reduction by the rough rolling mill 10 are appropriately performed according to the hardness and thickness. The steps under pressure are alternately combined as appropriate.

As described above, by using the width reduction press 8, a large width reduction amount can be obtained with respect to the slab a. Therefore, the width dimension required to make the slab a an arbitrary width dimension after the rough rolling is different. The number of molds can be reduced, and the cost of the mold can be reduced.

Also, since the number of molds is reduced, the time and labor required for mold replacement and the like are reduced, and the overall rough rolling efficiency for the non-ferrous metal slab a can be increased.

Further, as shown in FIG. 3, the width reduction press 8 applies a compressive force d in the line direction without applying a tensile force in the line direction to the slab a, so that a fish tail is formed at the front and rear ends of the slab a. Thus, the amount of the defective shape portion which must be cut by the shear 11, that is, the crop amount is reduced, and the yield is improved.

In addition, since the slab a receives the compressive force d in the line direction by the width reduction press 8, the inside of the slab a has no or small tensile stress in the line direction after the rough rolling, and the center formed therein during casting by the mold. The porosity or cavity is pressed by the compressive force d, resulting in improved internal quality.

In the present invention, when the nonferrous metal slab a is hard and thick, the slab a is first thinned in the thickness reduction step by the rough rolling mill 10 and then the width reduction is performed by the width reduction press 8.

By doing so, since the thickness of the slab a and the width reduction are in a substantially proportional relationship, the necessary width reduction force can be reduced.

Further, when the non-ferrous metal slab a is hard and thick, the step of reducing the width of the slab a by the width reduction press 8 is performed by the rough rolling mill 10.
The process is performed a plurality of times while alternately performing the process of reducing the thickness by the above method.

Since the non-ferrous metal has a large difference in hardness, if the width reduction step is performed once, the press capacity of the width reduction press 8 must be set large according to the hardest non-ferrous metal. The press capacity is excessive for soft non-ferrous metals, but if the width reduction process is divided into multiple steps, the width reduction force per operation can be small, so the press capacity of the width reduction press 8 is required. Can be reduced within a range in which the width reduction amount can be obtained.

FIG. 4 is an experimental result showing the relationship between the thickness of the slab a and the width reduction, and shows that the slab is a hard slab e, a slab f of a medium hardness,
When the width reduction amount is larger than the soft slab g (solid line),
The case where the width reduction amount is medium (dotted line) and the case where the width reduction amount is small (virtual line) are examined.

As a result of the above experiment, it was actually confirmed that the thickness of the slabs e, f, and g and the width reduction force were in a substantially proportional relationship in each case. It was confirmed that reducing the width in multiple times was effective in reducing the width reduction force.

Further, it was also found through experiments that the problem of buckling of the slabs e, f, and g did not occur even when the width of the slabs e, f, and g was reduced after the thickness was reduced.

FIG. 5 shows another embodiment of the present invention, in which a width reduction press 8 'is provided downstream of the rough rolling mill 10 and upstream of the shear 11 in a configuration substantially similar to that of FIG.

In this case, for example, rough rolling of the slab a corresponding to FIGS. 2 (b) and (c) can be performed by using the apparatus shown in FIGS. The effect can be obtained in the same manner as in the case of using.

FIG. 7 shows another embodiment of the present invention, in which a width reduction press 8 ″ is provided between the edger 9 and the rough rolling mill 10 in a configuration substantially similar to that of FIG. Approximately the same effect can be obtained.

In addition, the rough rolling method of the non-ferrous metal of the present invention is not limited to the above-described embodiment, and a plurality of rough rolling mills and width reduction presses may be provided if not a reversible type,
The width reduction press may be provided both upstream and downstream of the rough rolling mill, and it is needless to say that various changes can be made without departing from the gist of the present invention.

[Effects of the Invention] As described above, according to the method for rough rolling of non-ferrous metal of the present invention, the following excellent effects can be obtained because the width reduction press is used.

Since the width reduction amount can be increased, the number of molds to be prepared can be reduced, and slabs having various widths can be arbitrarily obtained.

Since the labor and time for exchanging the mold can be reduced, the efficiency of the rough rolling can be increased as a whole.

The generation of fishtail is suppressed by the compressive force, and the crop amount at the front and rear ends of the slab is reduced, so that the yield can be improved.

The compressive force prevents the generation of tensile stress in the line direction inside the slab, and the center porosity is pressed, so that the internal quality of the slab can be improved.

By performing the width reduction step and the thickness reduction step on the non-ferrous metal slab at least once alternately, the width reduction can be reduced by performing the thickness reduction first and then performing the width reduction. When the width reduction is performed in a plurality of times, the width reduction force per one time can be reduced, and the pressing ability of the width reduction press can be reduced.

[Brief description of the drawings]

FIG. 1 is a schematic plan view showing an example of an apparatus for carrying out the method of the present invention, FIG. 2 (a), (b) and (c) are the pass schedule diagrams of FIG. 1, and FIG. 3 is the width of FIG. Action diagram of the rolling press,
FIG. 4 is a diagram showing the relationship between the thickness of the slab and the width reduction force, FIG. 5 is a schematic plan view showing another example of the apparatus for carrying out the method of the present invention, and FIGS. FIG. 5 is a path schedule diagram, FIG. 7 is a schematic plan view showing another example of an apparatus for carrying out the method of the present invention, FIG. 8 is a schematic plan view of a conventional example, and FIG. FIG. In the figure, 8, 8 ', 8 "are width reduction presses, 10 is a rough rolling mill, a, e, f, g
Indicates a slab.

Claims (1)

(57) [Claims] (1) When a soft and thin slab is passed through a slab of a non-ferrous metal by providing equipment capable of optionally performing a width reduction step by a width reduction press and a thickness reduction step by a rough rolling mill; When passing a slab having a medium hardness and width, a width reduction step by a width reduction press is performed first, and a thickness reduction step by a rough rolling mill is performed one or more times later, When passing a hard and thick slab, first perform the step of reducing the thickness by a rough rolling mill at least once, and then perform the step of reducing the width by a width reduction press, and then repeat the above as necessary. A method for roughly rolling non-ferrous metals, whereby slabs of various widths can be obtained arbitrarily.