JPH04228222A - Extrusion machining device - Google Patents

Abstract

PURPOSE:To offer an extrusion machining equipment provided with a layer of heat insulating materials in the bolster of an extrusion tool. CONSTITUTION:By shutting off heat transmission by the layer of the insulating material 30, heat which is transmitted from a die 3 via a backer 4 or a die ring 6 is prevented from radiating externally through the bolster 7. Consequently, the development of a faulty extrusion, defective shape, insufficient accuracy, etc., of the extruding materials is prevented, and the well-proportioned and highly accurate extrusion materials are manufactured.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an extrusion processing apparatus, and particularly to an extrusion processing apparatus for metals such as aluminum materials.

0002

2. Description of the Related Art In an extrusion processing apparatus for aluminum materials, etc., as shown in FIG. ) is held by a die slide (5) fixed to the end platen (8) side. The extrusion tool (1) generally includes a die (3) having a die hole (3a), a backer (4) disposed adjacent to the front side of the die, a die ring (6) housing them, and a backer (4). It includes a bolster (7) placed on the front side, and is configured by a combination thereof. and,
By pressurizing the billet (B) that has been preheated and loaded into the container (2), the extruded material is extruded from the die hole (3a) of the die (3), thereby producing a product shape (S) with a predetermined cross-sectional shape in the front. is assumed to be obtained.

By the way, in the above-mentioned extrusion processing of aluminum materials, etc., the most important thing is to obtain the best possible dimensional and shape accuracy of the extruded material. For this purpose, the die (3) has conventionally been preheated to around 400° C. in a die oven to bring each part to a uniform temperature before use for extrusion. This preheating usually involves placing the dice (3) on the backer (4).
) etc., and heats the whole body in a die ring (6) as a holding tool. After preheating, it is assembled into a die slide (5) and supported, and moved to the extrusion position to extrude. Processing is about to start.

0004

[Problems to be Solved by the Invention] However, no matter how thoroughly the extrusion tool (1) including the die (3) is preheated, especially when attempting to manufacture a precision extruded material with a complicated shape, In particular, as the number of extrusions increases, irregularities in the metal flow from the die can lead to poor shape, irregular wall thickness, and twisted products, which are factors that reduce yield.

[0005] The inventors of the present invention have conducted various experiments and researches in order to elucidate the cause, and have found that the following causes the problem.

That is, the die (3) is used by preheating the entire die together with the backer (4) and die ring (6) adjacent to it, but the bolster (7) adjacent to the front side of the backer (4) and die slide for supporting extrusion tools (5
) is normally used at room temperature without being preheated, so during extrusion the heat from the die (3) is transferred to the bolster (7) and end platen (8) through the backer (4) and die ring (6). , heat is absorbed by the extruder main body side. For this reason, the die (3) is gradually cooled from the front side and the outer circumferential side, and over time the temperature inside the die becomes uneven, causing harmful shrinkage in the lower temperature area, which causes the extruded material to It has been found that this is one of the causes of defective shapes and poor appearance.

[0007]

[Means for Solving the Problems] Based on the above-mentioned findings, the present invention provides a heat insulating layer on the bolster to reduce the heat generated by the die, in order to enable precision extrusion with even higher precision. This system is designed to prevent heat from escaping and to maintain a uniform temperature state.

[0008] The gist of the present invention is an extrusion processing apparatus characterized in that a heat insulating material layer is provided on the bolster of the extrusion tool.

[0009]

[Operation] In the extrusion processing apparatus according to the present invention, the heat insulating layer is provided to suppress heat from the die from being transmitted to the outside through the surrounding members. Therefore, the die is prevented from dissipating heat, preventing its temperature from decreasing locally, and maintaining its temperature uniformly throughout the extrusion process.

0010

[Example] In the example shown in FIGS. 1 and 4, (
1) is an extrusion tool, (2) is a container, (3) is a die,
(4) is a backer, (5) is a die slide, (6) is a die ring, (7) is a bolster, and (8) is an end platen.

As shown in each figure, the bolster (7)
There are various types of
), and a heat insulating material layer (30) is provided in the middle of the thickness of the semi-bolster ring (7a).

Further, FIG. 2 shows a case of an integral type bolster (7), in which a heat insulating material layer (30) is provided in the middle part of its wall thickness.

FIG. 3 also shows a two-part bolster (7) having first and second bolsters (7a) and (7b).
In this case, a heat insulating material layer (30) is provided within the first bolster (7a).

Furthermore, FIG. 4 also shows the case of a two-part bolster (7), in which the first and second bolsters (
7a and 7b are each provided with a heat insulating material layer (30).

Bolster (7) as in these examples
By providing a heat insulating layer (30) on the bolster (7), it is possible to increase the heat retention ability of the bolster (7) itself and prevent a drop in its temperature. From backer (4) or die ring (6
) can be suppressed from being radiated to the outside through the bolster (7). Therefore, it is possible to prevent the temperature from decreasing, especially from the front side of the die (3).

Moreover, by providing the heat insulating layer within the thick portion of the bolster (7) as in the above embodiment, the life of the heat insulating layer (30) can be extended.

It goes without saying that the heat insulating material layer (30) should be made of a heat resistant heat insulating material such as glass wool or asbestos.

[0018]

[Effects of the Invention] As mentioned above, since the extrusion tool is provided with a heat insulating material layer on its bolster, the present invention reduces the temperature caused by heat radiation from the front side or the outer circumference side, which is the main heat radiation path of the die. It is possible to prevent or suppress a local temperature drop in the die throughout the extrusion process. Therefore, even when extrusion processing is continued for a long time, it is possible to avoid various problems caused by temperature changes in the die, and prevent the occurrence of problems such as poor ejection, poor shape, and poor precision of the extruded material. This makes it possible to produce a well-balanced and highly accurate extruded material.

Furthermore, since the bolster is provided with a heat insulating layer, there is an advantage that even if the die is changed, the same bolster having a heat insulating layer can be used in common.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view showing an embodiment of an extrusion processing apparatus of the present invention.

FIG. 2 is a longitudinal sectional view showing another embodiment.

FIG. 3 is a longitudinal sectional view showing still another embodiment.

FIG. 4 is a longitudinal sectional view showing still another embodiment.

[Explanation of symbols]

1...Extrusion tool 2...Container 3...Dice 7...Bolster 30...Insulating material layer

Claims (1)

[Claims] 1. An extrusion processing apparatus characterized in that a bolster of an extrusion tool is provided with a heat insulating material layer.