JPH06299208A - Method and device for dripping molten metal from tundish - Google Patents

Abstract

PURPOSE:To prevent the mixture of slag in molten metal dripped from a tundish into a product, to enable the reuse of the tundish and to provide the high purity product in a low cost, in gas atomizing equipment. CONSTITUTION:In the tundish 1, a molten metal sucking pipe 5 inserted into near a pouring nozzle 3, a blower 7 for sucking the molten metal through the molten metal sucking pipe 5 and a molten metal solidifying box 9 arranged at the front of the blower 7 are arranged. The blower 7 is started to drive in a little before dripping the molten metal to suck out the molten metal remaining in the tundish 1. The sucked-out molten metal is stuck to a baffle plate 9b in the solidifying box 9 and solidified. In this result, the molten metal containing the slag content is not dripped and impurity is not mixed into the product and therefore, the molten metal is not solidified at the part of the pouring nozzle 3, the tundish 1 can be reused.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for dropping a molten metal from a tundish and a device therefor for carrying out a treatment such as atomizing.

[0002]

2. Description of the Related Art Conventionally, gas atomization or water atomization has been carried out when producing metal or alloy powder. In this gas atomization or the like, as shown in FIG. 3 (A), the molten metal is gradually supplied from the melting furnace 100 to the tundish 103 arranged above the gas atomizer 101, and the molten metal is dripped from the bottom of the tundish 103. The powder is pulverized with high pressure gas and solidified. At this time, impurities such as slag may float in the molten metal in the tundish 103, particularly near the molten metal surface. Therefore, if the molten metal is completely dropped from the tundish 103 after pouring from the melting furnace 100,
A powder containing this slag is produced.

Since it is extremely difficult to remove such mixed powders from other powders, conventionally, as shown in FIG. 2B, before the molten metal has been dripped from the tundish 103, the molten metal nozzle can be used. The molten metal nozzle 10 is formed by using the protruding burl 107 which is made to fit exactly into the nozzle 105.
No. 5 was closed so that molten metal containing slag was not dropped.

[0004]

Therefore, according to the conventional method, when the tundish 101 is used once, the vicinity of the molten metal nozzle 105 is solidified by the molten metal containing the slag, and the tundish 101 is reused as it is. There was a problem that I could not do it.

Therefore, the present invention makes it possible to prevent impurities from being mixed into the product and to reuse the tundish when performing a predetermined treatment while dropping the molten metal from the tundish, such as atomization. The purpose is to do.

[0006]

Means and Actions for Solving the Problems A method of dropping molten metal from a tundish according to the present invention, which has been made to achieve the above object, is a method of dropping a molten metal or an alloy from a tundish into a predetermined molten metal. When the process of (1) is performed, the upper part of the molten metal is sucked and discharged when the dropping of the molten metal is almost completed.

According to the molten metal dropping method from the tundish of the present invention, when the molten metal is almost completely dropped, the slag on the upper portion of the molten metal is sucked and discharged, so that the slag floating near the molten metal surface is not dropped. Only the molten metal without slag can be dropped. The molten metal dropping apparatus of the present invention suitable for carrying out this molten metal dropping method is a molten metal dropping apparatus that performs processing on the molten metal while dropping the molten metal or alloy from the tundish, and a suction port near the bottom of the tundish. Is provided with a molten metal suction means.

According to the molten metal dropping apparatus of the present invention, since the suction port of the molten metal suction means is arranged near the bottom of the tundish, when the molten metal dropping is almost completed, the molten metal suction means is driven to near the molten metal surface. It is possible to remove slag and the like floating in the room and discharge it. In this molten metal dropping device, it is preferable that the molten metal suction means includes a solidifying means for adhering and solidifying the molten metal before the suction means. Since the molten metal does not reach the suction means due to the presence of the solidifying means, it is possible to prevent the suction means from being damaged by the molten metal.

[0009]

EXAMPLES Next, examples will be described below in order to further clarify the present invention. The embodiment relates to the tundish 1 installed on the upper part of the gas atomizing apparatus 10 as shown in FIG.

The gas atomizing apparatus 10 includes a chamber 11
The metal or alloy molten metal dropped from the upper tundish 1 is atomized by the gas atomizer 15 and solidified while falling in the chamber 11 to produce powder. This powder is collected in the recovery container 20. It is collected and then sent to the subsequent process such as classification.

Above the tundish 1, a tiltable induction heating type melting furnace 2 is provided. At the time of atomizing, the molten metal is poured into the tundish 1 from the melting furnace 2 by a predetermined amount in several times. The second and subsequent pourings from the melting furnace 2 to the tundish 1 are performed before the molten metal that has been poured before is completely dropped. Therefore,
The amount of slag floating on the surface of the tundish 1 rises again and is not dropped during the process. However, when the last pouring from the melting furnace 2 into the tundish 1 is completed and the molten metal in the tundish 1 is reduced, the slag portion floating near the surface of the molten metal becomes a problem.

In order to deal with this problem, in this embodiment, the tundish 1 has a molten metal suction pipe 5 inserted up to the vicinity of the pouring nozzle 3 and the molten metal suction pipe 5.
A blower 7 for sucking the molten metal through the blower and a molten metal solidifying box 9 provided in front of the blower 7 are arranged. The molten metal solidification box 9 has a punching metal 9a on the blower 7 side.
And a baffle plate 9b on the tundish 1 side.

The system of this embodiment is operated in the procedure as shown in FIG. First, the slide nozzle 3a provided at the pouring nozzle 3 portion of the tundish 1 is closed (S10). Then, the tundish 1 is filled with molten metal from the melting furnace 2 (S20). Next, the gas atomizer 15 is activated to start gas atomization (S3).
0). Then, the slide nozzle 3a is "opened" to start dropping molten metal (S40).

In this state, when the molten metal in the tundish 1 is reduced to some extent, a predetermined amount of molten metal is added from the melting furnace 2 again (S50). After the last addition, when the remaining amount of the molten metal in the tundish 1 becomes less than a predetermined amount (S60), the blower 7 is activated and the tundish 1
The molten metal inside (mainly slag) is sucked (S70).
Then, the blower 7 is stopped after the molten metal is completely discharged to the outside of the tundish 1 (S80, S90).

As a result of the above configuration, in the system of the embodiment, the molten metal is effectively dropped, while the slag component of the last remaining molten metal, especially the supernatant, is sucked out through the molten metal suction pipe 5. Therefore, lightweight impurities such as slag are not mixed in the powder continuously produced by the system of this embodiment. As a result, highly pure metal powder can be provided at low cost.

Further, the molten metal does not excessively solidify at the pouring nozzle 3 portion of the tundish 1. As a result, the tundish 1 can be reused without replacing the pouring nozzle 3. Therefore, if the tundish 1 is left as it is and filled with the molten metal again, it becomes possible to continuously manufacture metal powders in many lots.

Further, in the molten metal solidification box 9, most of the sucked molten metal adheres to the baffle plate 9b and solidifies, and the splash of molten metal is also blocked by the punching metal 9a, so that the blower 7 is damaged by the molten metal. I will not receive it. Although the embodiments of the present invention have been described above, it is needless to say that the present invention is not limited to the above-mentioned embodiments and can be implemented in various modes without departing from the scope of the invention.

Needless to say, the method and apparatus of the present invention can be applied not only to a gas atomizing apparatus but also to a water atomizing apparatus and a process other than atomizing. Further, the pipe for sucking the molten metal may not be installed at the bottom of the tundish from the beginning, but may be inserted from the upper part of the tundish at a necessary timing.

[0019]

As described above, according to the method of dropping molten metal from a tundish of the present invention, when a predetermined treatment is performed while dropping the molten metal from a tundish such as atomization, impurities are added to the product. It can prevent the tundish from being mixed, and can reuse the tundish,
High-purity products can be provided at low cost.

Further, according to the molten metal dropping apparatus of the present invention, such a molten metal dropping method can be surely carried out, and in particular, according to the apparatus of claim 3, damage to the molten metal suction means in the molten metal dropping apparatus can be prevented. Can also be prevented.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a schematic configuration of a continuous production facility for metal powder as an example.

FIG. 2 is a flowchart of work steps in the metal powder continuous production facility of the example.

FIG. 3 is an explanatory diagram of a method of dropping molten metal from a tundish in a conventional metal powder manufacturing facility.

[Explanation of symbols]

1 ... Tundish, 2 ... Melting furnace, 3 ... Melting nozzle, 3a ... Slide nozzle, 5 ... Molten suction pipe, 7 ... Blower, 9 ... Molten solidification box , 9a ... punching metal, 9b ... baffle plate,
10 ... Gas atomizing device, 20 ... Recovery container.

Claims (3)

[Claims] 1. When the molten metal or alloy is dropped from a tundish and a predetermined treatment is performed on the molten metal, when the dropping of the molten metal is near, the upper part of the molten metal is sucked and discharged. How to add molten metal from a tundish. 2. A molten metal dropping device for performing a treatment on a molten metal or an alloy while dropping the molten metal from a tundish, comprising a molten metal suction means having a suction port near the bottom of the tundish. A molten metal dropping device. 3. The molten metal dropping apparatus according to claim 2,
A molten metal dropping device, wherein the molten metal suction means comprises a solidifying means for adhering and solidifying the molten metal before the sucking means.