JPH08157938A - Device for preventing closing of gas piping for molten metal stirring device - Google Patents

Abstract

PURPOSE: To provide a mechanism for a gas blowing porous plug which does not degrade durability, is safe and prevents closing with low viscosity metals. CONSTITUTION: This mechanism is disposed between a gas introducing pipe 5 of the gas blowing porous plug 3 and a gas supply pipe, is connected to these pipes, respectively, and assures the supply of the gas by communicating a gas piping 7, the gas introducing pipe 5 and the porous plug 3 without closing the gas piping from a gas supply source with the low viscosity metals, such as aluminum and lead, included in molten metal, even if the low viscosity metals penetrate these pipes through the gas vent holes of the porous plug 3 and the gas introducing pipe 5. The closing of the gas piping by the stagnating and solidifying of the low viscosity metals is prevented, by which the safe and stable operation is assured at a low cost.

Description

Detailed Description of the Invention

[0001]

The present invention relates to a steelmaking process,
The present invention relates to a gas pipe blockage prevention device for a molten metal stirring device in which a gas injection porous plug is attached to a molten metal container to stir molten metal.

[0002]

2. Description of the Related Art In refining molten metal, it is common practice to blow an inert gas such as argon or nitrogen into the molten metal. As this method, a gas injection porous plug is used at the bottom of a metal ladle, and a pipe from a gas supply source is connected to a gas introduction pipe of the porous plug.

[0003]

In refining molten metal, particularly in refining molten steel, an inert gas such as argon or nitrogen is blown from a gas injection porous plug to adjust the composition, and the composition is adjusted together with degassing. Various metals are added. Metals with low viscosity during refining, such as aluminum,
Lead, etc., passes through the pores of the gas injection porous plug or the gas passage hole and solidifies or stays in the gas introduction pipe and the pipe from the gas supply source to determine the amount of supply gas necessary for stirring for refining the molten metal. It was sometimes impossible to flush. Further, after the molten metal was discharged, the gas was not communicated with the porous plug for blowing gas, and the gas could not be reused when the ventilation was confirmed.

As a countermeasure against this problem, the use of a lance pipe which is inserted from the top of the ladle and blows gas. Φ2 in the gas inlet pipe of the porous plug for gas injection
Put ~ 5 mm steel bar to promote solidification of low viscosity metal in the inlet tube. The gas blowing plug used in the refining with the addition of low-viscosity metal is always replaced with a new porous plug after one use. In this method, the cost is high, but it is possible to prevent the pipe from the gas supply source from being blocked, but since it is blocked by the gas introduction pipe, the porous plug should be replaced every time. is necessary. In the other method, there is a risk of blockage during refining, and since it is replaced with a new one every time, the cost is high. Therefore, there has been a strong demand for a mechanism of a gas-blowing porous plug that does not deteriorate the service life, is safe, and does not cause blockage due to a low-viscosity metal.

[0005]

DISCLOSURE OF THE INVENTION The present invention is arranged between a gas introduction pipe and a gas supply pipe of a gas-blowing porous plug, connected to each of them, and made of aluminum, lead, etc. contained in molten metal. Even if the low-viscosity metal penetrates through the gas passage hole and the gas introduction pipe of the gas injection porous plug,
A gas pipe for a molten metal stirring device, characterized in that the gas pipe from the gas supply source is not blocked by the low-viscosity metal, and the gas pipe and the gas introduction pipe and the porous plug can communicate with each other to supply gas. It is a blockage prevention device.

[0006]

The gas pipe blockage prevention device 6 of the molten metal agitator according to the present invention is connected to the gas introduction pipe 5 of the porous plug on the upper surface and is connected to the pipe 7 from the gas supplier on the upper side surface.
The gas pipe blockage prevention device 6 has a hollow inside, and the low-viscosity metal that has permeated through the porous plug and the gas introduction pipe stays below the connection portion 7a of the upper side surface with the pipe 7 from the gas supply source. The inert gas for blowing is communicated with the gas introduction pipe through the upper cavity in which the low-viscosity metal stays in the gas pipe blockage prevention device of the present invention. In this way, the gas pipe from the gas supply source can be continuously used and reused without being blocked. A discharge port 9 for low-viscosity metal is provided at the bottom of the gas pipe blockage prevention device 6, and the discharge port 9 is used during refining.
After the cap is closed and gas is blown into it, the cap of the discharge port 9 is opened and the low viscosity metal accumulated in the gas pipe blockage prevention device is discharged, so that this device can be used repeatedly. Can be used semi-permanently.

[0007]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a vertical cross-sectional view of a method of mounting a gas pipe blockage prevention device 6 according to the present invention. The gas pipe prevention device 6 has a cylindrical box shape with a hollow inside and is for blowing gas into the top. A connecting portion 5a for connecting to the gas introducing pipe 5 of the porous plug 3 is provided and connected to the gas introducing pipe. In addition, a connecting portion 7a for connecting to the gas pipe 7 from the gas supply source is provided on the upper side surface and is connected to the gas pipe 7. As the connection method, a quick joint method, a flange method, or the like is used. Further, a discharge port 9 for discharging the retained low-viscosity metal after use is provided at the bottom of the apparatus, and is closed by a screw type cap.

During the gas blowing for stirring the molten metal during the refining of the molten metal, the low-viscosity metal that has permeated through the gas passage hole of the gas-blowing porous plug 3 and the gas introduction pipe 5 is the low-viscosity metal retention part 8 of this apparatus. The low viscosity metal does not enter the gas pipe 7 from the gas supply source connected to the gas pipe connecting portion 7a on the upper side surface of the device,
The low-viscosity metal is prevented from staying, solidifying, and blocking in the gas pipe 7 and stopping the gas supply.

Therefore, the gas pipe blockage prevention device of the present invention is provided with a gas introduction pipe of the gas injection porous plug 3,
By arranging between the gas pipes from the gas supply source and connecting them, the supply gas for melting and stirring passes through the gas pipes 7 and the hollow portion in the upper part of the gas pipe blockage prevention device 6, It is sent to the gas blowing porous plug 3 via the introduction pipe 5.

FIG. 2 is a vertical cross-sectional view of a conventional method for connecting a gas injection porous plug 3 for melt agitation and a gas pipe 7 from a gas supply source. The gas introduction pipe 5 and the gas pipe 7 are joints 10. The low-viscosity metal stays and solidifies in the gas pipe 7 and is clogged to prevent the supply gas for stirring the molten metal from passing through the porous plug 3 into the molten metal.

[0011]

The gas pipe blockage preventive device 6 of the molten metal stirring device according to the present invention serves as a gas passage hole of the gas blowing porous plug 3 and a gas introduction pipe 5 during stirring of molten metal by gas blowing in the steelmaking process. By connecting the gas pipe 7 from the gas supply source through this device 6, the low viscosity metal in the gas pipe is prevented from being accumulated and blocked by solidification, so that safe and stable operation can be performed at low cost. This is a device that can be secured.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a method for mounting a gas pipe blockage prevention device according to the present invention.

FIG. 2 is a vertical cross-sectional view of a conventional connection method.

[Explanation of symbols]

 1 Molten metal container 2 Porous tuyere brick 3 Porous plug 4 Bottom iron skin 5 Gas inlet pipe 5a Connection part 6 Gas pipe blockage prevention device 7 Gas pipe 7a Connection part 8 Low viscous metal retention part 9 Discharge port 10 Joint

Claims (1)

[Claims] In a molten metal agitator that attaches a porous plug to a molten metal container and agitates molten metal, it is possible to connect a gas introduction pipe and a gas supply pipe of a gas injection porous plug,
Even if a low-viscosity metal such as aluminum or lead contained in the molten metal permeates through the gas passage hole and the gas introduction pipe of the gas injection porous plug, the low-viscosity metal does not block the gas pipe, A gas pipe blockage prevention device for a molten metal agitator, which is capable of supplying gas by communicating with a gas introduction pipe and a porous plug.