JP2003112220A - Extrusion method and device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an extrusion method that can eliminate generation of defects such as blistering by reducing formation of an air layer between a billet remaining to be extruded and a billet to be consecutively extruded. SOLUTION: In a metallic material extruding method by loading a billet in a billet hole of a container, extruding the billet through an extruding die, cutting the remainder of the extrusion, and consecutively extruding billets; the extruding machine is characterized by the shearing device for cutting the remainder of the extrusion in that the cutting part is formed in a circular arc shape and that the recessed area of the circular arc strikes the remainder as the shearing blade.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for extruding metal, especially aluminum (including aluminum alloy, the same applies hereinafter).

[0002]

2. Description of the Related Art In aluminum extrusion, a heated billet is charged into a billet hole of a container, the stem is advanced to fill the billet hole of the container (upset step), and then the stem is further advanced. The billet is extruded through an extrusion die to obtain an extruded material having a predetermined cross-sectional shape.

Usually, in factory production, in order to prevent the outflow of the skin layer of the billet to the extruded material, a predetermined imprint is left, after cutting this imprint, the next billet is charged and continuously extruded. To continue.

In this case, if the residual cutting is not properly performed, an air layer is formed between the end face of the port after the residual cutting and the billet for joint pressing. The flow entrains air, which may cause defects such as blister in the extruded material.

[0005]

SUMMARY OF THE INVENTION The present invention has been made to solve this problem, and its purpose is to provide an air gap between the end face of the port portion after cutting the residual residue and the billet for joint pressing. It is an object of the present invention to provide an extrusion processing method using an imprint cutting shear which can reduce the formation of layers and eliminate the occurrence of defects such as blisters, and an extrusion apparatus for carrying out the extrusion method.

[0006]

In order to achieve the above-mentioned object, an extrusion processing method according to a first aspect of the present invention is such that a billet is inserted into a billet hole of a container, and extrusion is performed through an extrusion die, followed by extrusion. In the metal extrusion method of cutting the rest and continuously pushing the billet to continue extrusion, as a shear for cutting the press residue, the shape of the cutting portion is formed in an arc shape,
It is characterized in that a shearing type shearing machine having a cutting blade adapted to cut an uncut residue on the arcuate concave surface side is used.

An extrusion apparatus according to a second aspect of the present invention is an apparatus for carrying out the extrusion processing method according to the first aspect, wherein a cutting blade for cutting the residue is detachably attached. It is characterized by

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION According to the present invention, in the method of extruding metal, particularly aluminum, the shape of the cutting portion is arcuate, and the concave side of the arcuate is applied to the imprint to cut the imprint. It is characterized by using a shear type shear with a cutting blade, and a good cutting surface can be obtained by cutting the uncut residue with a shear type shear with a cutting blade with an arc-shaped cutting part. The formation of an air layer between the unpressed portion and the billet for continuous pressing is reduced.

FIGS. 1 and 2 show the relationship among the billet holes, the dies, the residuals, and the shears of the container according to the present invention. The radius r of the arcuate portion 2 of the cutting blade 1 is the billet of the container 3. It is preferable to set it to 50 to 60% of the diameter R of the hole 4, and if it is less than 50% or more than 60%, it is difficult to obtain a good cut surface, and the extruded material E is likely to have defects.

In FIGS. 1 and 2, both ends 5 of the arc-shaped portion 2 of the cutting blade 1 and the billet of the container 3 when the cutting blade 1 of the shear descends in the direction of the arrow and comes into contact with the remnant D. It is preferable that the fan-shaped central angle α formed by the center of the hole 4 be 90 to 180 °, and this central angle α is the cutting edge 1.
It is determined by the radius r of the arc-shaped portion 2.

The thickness t (FIG. 2) of the cutting blade 1 is equal to that of the container 3
It is preferable that the size is 10 to 40% of the diameter R of the billet hole 4, and if it is less than 10%, the cutting blade is too thin and the rigidity of the shear is insufficient. It is difficult to obtain a surface, and defects are likely to occur in the extruded material E.

The thickness T (FIG. 2) of the uncut portion D is 150% or less of the thickness of the cutting blade 1, preferably 80% of the thickness of the cutting blade.
~ 105%, more preferably 80 ~ of the thickness of the cutting blade
100%, most preferably 95-100%,
It is preferable for obtaining a defect-free extruded material.

The cutting blade 1 of the present invention is detachable so that it can be used in place of the existing cutting blade of a shear that is conventionally provided in an extruder for cutting an uncut residue. Extrusion using the cutting blade 1 according to (1) is carried out by mounting it on an existing shear.

[0014]

EXAMPLES Examples of the present invention will be described below in comparison with comparative examples. This example shows one embodiment of the present invention, and the present invention is not limited to this.

Example 1 An aluminum alloy billet having the composition shown in Table 1 was passed through a porthole die by means of an extruder equipped with a shearing shear equipped with a cutting blade having an arc-shaped cutting portion to form a cylindrical product. Was extruded.

The radius r of the arcuate portion is 120 mm (57% of the diameter (210 mm) of the billet hole of the container), and α
Was 120 °, the thickness t of the cutting blade was 40 mm (19% of the diameter of the billet hole of the corner insert), and the thickness T of the unpressed portion was 40 mm.

As a result of investigating the occurrence of defects in the extruded material obtained, no defects were observed.

[0018]

[Table 1]

Example 2 As in Example 1, a cylindrical product was extruded through a porthole die by an extruder equipped with a shearing shear equipped with a cutting blade having an arc-shaped cutting portion.

However, the radius r of the arcuate portion is 100 mm (48% of the diameter (210 mm) of the billet hole of the container), α is 30 °, and the thickness t of the cutting blade is 40 mm (of the diameter of the billet hole of the container). 19%), the remaining thickness T is 40 m
m.

As a result of investigating the occurrence of defects in the obtained extruded material, it was observed that some blistering occurred due to the small radius of the arcuate portion of the cutting blade.

Comparative Example 1 In the same manner as in Example 1, a cylindrical product was extruded through a port hole die by an extruder equipped with a shearing shear having a cutting blade whose cutting portion had an arc shape.

However, the radius r of the arcuate portion is 120 mm (57% of the diameter (210 mm) of the billet hole of the container), α is 120 °, and the thickness t of the cutting blade is 40 mm (of the diameter of the billet hole of the container). 19%), and the thickness T of the remaining press is 20
mm.

As a result of investigating the occurrence of defects in the obtained extruded material, defects were found due to the small thickness of the imprint.

Comparative Example 2 In the same manner as in Example 1, a cylindrical product was extruded through a porthole die by an extruder equipped with a shearing shear equipped with a cutting blade having an arc-shaped cutting portion.

However, the radius r of the arc-shaped portion is 120 mm (57% of the diameter (210 mm) of the billet hole of the container), α is 120 °, and the thickness t of the cutting blade is 40 mm (of the diameter of the billet hole of the container). 19%), the remaining thickness T is 10
It was set to 0 mm.

As a result of investigating the state of generation of defects in the obtained extruded material, defects were caused due to the thickness of the unpressed portion being too thick.

Comparative Example 2 In the same manner as in Example 1, a cylindrical product was extruded through a port hole die by an extruder equipped with a shearing shear equipped with a cutting blade having an arc-shaped cutting portion.

However, the radius r of the arcuate portion is 120 mm (57% of the diameter (210 mm) of the billet hole of the container), α is 120 °, and the thickness t of the cutting blade is 10 mm (of the diameter of the billet hole of the container). 5%), the remaining thickness T is 40 m
m.

As a result of investigating the state of occurrence of defects in the obtained extruded material, defects were caused due to the cutting blade being too thin.

[0031]

According to the present invention, the formation of an air layer between the unpressed portion and the billet for continuous pressing is reduced, and the occurrence of defects such as blisters can be eliminated.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view showing a relationship between a cutting blade and an unpressed portion in the present invention.

FIG. 2 is a partial cross-sectional side view showing a cutting mode of the unpressed portion in the present invention.

[Explanation of symbols]

1 cutting blade 2 arc-shaped part 3 containers 4 billet holes 5 Both ends of arcuate part 2 6 dice Diameter of R billet hole r Radius of arcuate part D leftover E Extruded material t Thickness of cutting blade 1 Thickness of T

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Hideya Hayakawa             Sumitomo Light Gold 5-11-3 Shimbashi, Minato-ku, Tokyo             Inside the industry F-term (reference) 3C039 AA02 AA25                 4E029 XA04

Claims (2)

[Claims] 1. A metal extrusion method in which a billet is charged in a billet hole of a container, extruded through an extrusion die, and then the unpressed residue is cut, and the billet is continuously pushed to continue extrusion. A shearing type shearing method is used, wherein a shearing shear is used as a shear, in which a cutting portion is formed in an arc shape, and a cutting blade that cuts an uncut residue on the concave side of the arc shape is used. 2. The extrusion apparatus for carrying out the extrusion processing method according to claim 1, wherein a cutting blade for cutting the unpressed portion is detachably attached.