JPS61180669A - Method and device for casting - Google Patents

Abstract

PURPOSE:To prevent surely the intrusion of foreign matter such as oxide or gas into a molten metal by filtering the molten metal by a filter then casting the molten metal while the molten metal is held contactless with the outdoor air. CONSTITUTION:The molten metal 2 in a vessel 1 for the molten metal is dropped into a filter section 5 so that the inside of the filter section 5 is filled with the molten metal 2. The metal 2 is heated by a heater 7 to prevent the cooling of the molten metal. The metal 2 is then filtered by the ceramic filter 6 by which the foreign matter contained in the metal 2 is removed. The molten metal is continuously cast in this state in a casting mold section 8. The filtered metal 2 is immediately cast without being brought into contact with the foreign matter generating source according to the above-mentioned method and therefore an ingot 11 which is free from the foreign matter is obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a casting method and apparatus for the same, in which the treatment process of molten metal in the final stage before molding is improved.

[Prior Art] Conventionally, when casting various metals for processing, attempts have been made to remove foreign substances from molten metal by filtering it with a filter such as a ceramic filter. An example of this type of casting method is disclosed in, for example, Japanese Patent Laid-Open No. 142162/1983.

[Problems to be Solved by the Invention] However, even if the molten metal is filtered through a filter or the like, there is a problem in that foreign matter gets mixed into the molten metal again just before the mold. In particular, oxides and degassing residue may be mixed in from the outside air in contact with the molten metal, resulting in insufficient purity of the resulting ingot or the presence of gas defects in the ingot. There was a problem.

Furthermore, in the conventional method for preventing foreign matter contamination that involves filtration, turbulent flow occurs in the molten metal in the filtration section, and there is a problem in that the cargo is more likely to be caught in the turbulent flow.

Therefore, an object of the present invention is to provide a casting method and an apparatus therefor that can reliably prevent the contamination of oxides or gas-only tributes.

Means for Solving Problem E] In the casting method of the present invention, molten metal is first filtered using a filter. Next, a mold part is connected to the surface of the filter opposite to the side to which molten metal is supplied, and the space between the filter part and the mold part is cut off from contact with outside air, and casting is performed in this state. It is characterized by

Further, in the casting apparatus of the present invention, a space is formed between the filter for filtering the molten metal and the filter on the side opposite to the side to which the molten metal is supplied, which is shut off from the outside air. and a mold part connected to make the mold part.

[Operation 1] In this invention, the VF manufacturing is performed in a state in which the space after the filter, that is, the space between the filter and the mold part, is filled with molten metal, and the contact between the molten metal and the outside air is cut off. At a later stage, the molten metal does not come into contact with a source of foreign matter until it becomes an ingot, and no turbulence occurs in the molten metal located after the filter.

[Description of Embodiment] An embodiment of the present invention will be described below with reference to the drawings.

The accompanying drawing is a vertical sectional view schematically showing a casting apparatus according to an embodiment of the present invention. Molten metal 2 is stored in molten metal alffI. A tapered through hole 1a is formed at the bottom of the molten metal m1.
A stopper 3 is arranged in the molten metal bath 1, which can close the molten metal tank 1. The stopper 3 is provided in order to adjust the supply speed of the molten metal 2, and when the molten metal 2 is caused to flow down from the molten metal tank 1, the stopper 3 is placed one distance from the through hole 1a, and on the other hand, When stopping the supply of molten metal 2, the through hole 1a is moved to close.

Further, the conduit 4 forming the opening hole 1a is made of molten metal Pa1.
The conduit 4 is inserted into the top plate 5a of the filter section 5 disposed below. In this embodiment, the joint between the top plate 5a and the conduit 4 is sealed to prevent gas and liquid from leaking to the outside from the joint.

A ceramic filter 6 as a filter is attached to the lower end of the filtration part 5. Further, a heating bag [7 is arranged around the filtration part 5, that is, near the surface of the ceramic filter 6 on the side where the molten metal 2 is supplied, and the molten metal wh
It is configured to prevent cold H inside the filter section 5 of No. 2.

A mold section 8 is connected below the ceramic filter 6 . The mold part 8 has a cylindrical part 9 joined to the ceramic filter 6, and a cooling device f! is installed around the cylindrical part 9. f
10 is installed. That is, the cooling device 10 causes the il! The molten metal 2 that has been heated is cooled and solidified to become an ingot 11.

By the way, a sealed space is formed between the ceramic filter 6 and the mold part 8 by the ceramic filter 6, the cylindrical part 9, and the ingot 11, and the space is filled with the filtered molten metal 2. Become. Therefore, the molten metal 2 filtered by the ceramic filter 6 is prevented from coming into contact with sources of foreign matter contamination, such as the atmosphere, and is prevented from generating turbulence.

In order to cool the ingot 11, cooling showers 13.13... are arranged downstream of the mold section 8, and although not particularly shown, cooling showers 13.13... are arranged at the lower end of the cooling showers 13.13... A drive roller and the like are arranged so that the cast and polished ingot 11 is continuously sent out.

In the casting apparatus of the embodiment shown in the drawings, first, the molten metal tank 1 is
The inside is filled with molten metal 2. Thereafter, by setting the stopper 3 at a distance 111 from the through hole 1a as shown in the figure, the molten metal 2 is allowed to flow down into the filtration section 5, and the inside of the filtration section 5 is filled with the molten metal 2. In this state, the molten metal 2 is heated by the heating device 217 disposed around the filter section 5, thereby preventing the molten metal 2 from cooling. Therefore, the filtration speed of the ceramic filter 6 can be prevented from decreasing.

Next, foreign matter contained in the molten metal 2 is removed by filtering the molten metal 2 using the ceramic filter 6.

By the way, in the space formed below the ceramic filter 6, the filtered molten metal 2 is prevented from coming into contact with a source of foreign matter Ii such as air.

In this state, continuous casting is performed in the mold section 8.

Therefore, in the apparatus and method of this embodiment, since the filtered molten gold ji[12 is directly cast into a mold without contacting with a foreign matter source, an ingot 11 without any foreign matter mixed in can be produced.

Furthermore, since the closed space formed below the ceramic filter 6 is filled with the filtered molten metal 2, turbulence in the filtered molten metal 2 can be prevented as long as casting is continued in that state. , it is possible to more effectively prevent foreign matter from being entangled.

Preferably, another conduit 14 is provided on the top plate 5a of the filtration section 5.
By forming a conduit and connecting the conduit to pressure reducing means such as a vacuum pump, it is possible to effectively remove gas generated within the molten metal 2. That is, in general, gas components contained in the molten metal 2 tend to form bubbles during the process of forming the ingot 11, but the bubbles pass through the ceramic filter 6 and reach the top of the filtration section. Board 5
a can be discharged by the above-mentioned pressure reducing means.

Next, specific experimental results using the casting apparatus shown in the drawings will be explained.

A ceramic filter containing alumina as the main component and having an average pore diameter of 0.8I1m is used as the filter 6, and the cross section is 1501m.
Continuous & V-made square tough pitch copper.

At this time, a vacuum pump was connected to the upper part of the iL1 passage section 5 to exhaust air bubbles generated during molding. Further, in order to prevent a decrease in the filtration speed in the ceramic filter 6, the molten metal 2 was heated on the supply side of the ceramic filter 6 by the heating device 'a7, as in the above embodiment.

After hot rolling, the ingot thus obtained was subjected to wire drawing, peeling and intermediate annealing, and was wire drawn to a diameter of 0.03 fill.

For comparison, wire drawing was performed using the same material by the conventional continuous casting method without providing the ceramic filter 6 or the heating device 7.

As a result, according to the method of this invention, compared to the conventional method,
The average elongated IiI weight per wire breakage increased approximately three times.

[Effect of the Invention J As described above, according to the present invention, molten metal is filtered by a filter, a mold part is connected to the side of the filter opposite to the side to which the molten metal is supplied, and the filter and tk31 with the space between the mold part cut off from contact with the outside air! [
In other words, since it is filtered by a filter immediately before the mold part, it is possible to reliably prevent foreign matter from entering, which cannot be prevented by ordinary filtration with a simple filter.

In addition, since the filter and mold part are connected, turbulent flow due to pouring occurs only on the supply side of the filter, and no turbulent flow occurs between the filter and mold part, preventing foreign matter from being entrained. Therefore, foreign matter contamination can be prevented even more reliably.

It should be pointed out that the present invention can be used generally for manufacturing ingots for processing into various metal foils, thin wires, etc.

[Brief explanation of the drawing]

The drawing is a vertical sectional view schematically showing an embodiment of the present invention. In the figure, 2 is a molten metal, 6 is a ceramic filter,
7 is a heating device, and 9 is a mold section.

Claims (4)

[Claims] (1) Filter the molten metal with a filter, connect the mold part to the side of the filter opposite to the side to which the molten metal is supplied,
A casting method characterized in that casting is carried out in a state in which the space between the filter and the mold part is cut off from contact with outside air. (2) The casting method according to claim 1, wherein the molten metal is heated in the vicinity of the filter. (3) A filter for filtering molten metal, and a mold connected to the surface of the filter opposite to the side to which the molten metal is supplied so as to form a space shut off from outside air between the filter and the filter. A casting device comprising: (4) The casting apparatus according to claim 3, wherein heating means is provided near the filter.