JPH09323157A - Ladle for molten metal - Google Patents

Abstract

(57) [Summary] [Purpose] The purpose is to prevent molten metal from penetrating into the gas blowing plug when moving the ladle, thereby reusing the gas blowing plug and improving the number of times of use. [Structure] In order to prevent the penetration of the metal into the gas blowing plug 2 when the ladle is moved, it is composed of a gas cylinder 3 for livestock pressure, a circuit for performing livestock pressure there, and a normal gas blowing circuit, and a pipe 6 It is characterized by switching by replacing. [Effect] By using a gas cylinder and a special circuit for compressing the gas, the gas pressurized by the gas cylinder is supplied to the gas blowing plug even during movement, and the permeation of the molten metal into the gas blowing plug is suppressed. Became possible.
Therefore, the gas blowing plug can be reused and the number of times of use can be improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas blowing plug which is buried in the bottom of a ladle for molten metal and used for blowing gas into the molten metal in the ladle, and does not blow gas when moving the ladle. At times, the present invention relates to a storage gas cylinder for preventing penetration of molten metal into a gas blowing plug and a ladle for molten metal formed by separately providing a special circuit for performing storage pressure.

[0002]

2. Description of the Related Art Conventionally, a gas blowing plug that is buried in the bottom of a ladle for molten metal and blows gas to the molten metal in the ladle,
When moving the ladle after the gas blowing process, the molten metal enters the inside of the gas blowing plug during movement because it moves after disconnecting the gas piping, and if you try to use it again, it will be blocked in the plug. Because of this, it was often impossible to use. Therefore, a technique has been devised in which, as shown in FIG. 1, the pressure is stored in the gas cylinder 3 when the gas is blown, and the molten metal is suppressed from entering the plug by the gas stored in the gas cylinder 3 when the gas is moved. (Actual application Sho 64-1565
6) However, even if this technique was used, the storage pressure in the gas cylinder was not exerted, it was not very effective, and the penetration of molten metal was not suppressed.

In a conventional ladle for molten metal having a gas cylinder, a high-pressure gas normally passes through the cylinder when the gas is blown, and the molten metal does not enter the gas-blowing plug, but a high-pressure gas when moving. When the connection of the gas is disconnected, the gas stored in the cylinder is stored only to the same level as the pressure at the bottom of the ladle due to the molten metal in the ladle. It is considered that the gas in the blown plug flows upward due to the difference in specific gravity, so that the effect of suppressing the permeation of the molten metal is weakened with time, and finally the molten metal permeates into the gas blown plug. For this reason, there is a need for a technique that allows the storage pressure in the gas cylinder to be higher than the pressure of the molten metal in the ladle.

[0004]

SUMMARY OF THE INVENTION In the method of FIG. 1 described above,
Since the storage pressure that exceeds the pressure generated by the specific gravity of the molten metal in the ladle cannot be performed in the gas cylinder, the permeation of the molten metal into the gas blowing plug cannot be sufficiently suppressed when moving the ladle, and the flow rate of the gas blowing plug decreases. At last, it became clogged, and it was difficult to reuse the gas blowing plug.

In order to prevent the molten metal from penetrating into the gas blowing plug when the ladle is moved, a storage pressure exceeding the pressure generated by the specific gravity of the molten metal in the ladle can be performed in the gas cylinder, and at the time of movement. Also in the case of (1), if the gas can be blown little by little, it is possible to suppress the permeation of the molten metal into the gas blowing plug when the ladle is moved.

The present invention has been made in order to meet the above-mentioned demands, and enables a storage pressure in the gas cylinder to exceed the pressure generated by the specific gravity of the molten metal in the ladle.
In addition, by allowing gas to be blown in small amounts even when moving, it is intended to suppress the permeation of molten metal into the gas blowing plug when moving the ladle, thereby reusing the gas blowing plug and improving the number of uses. .

[0007]

According to the present invention, in the initial stage of gas blowing according to the method of FIG. 2, first, the livestock pressure is applied to the inside of the gas cylinder, and after the end of the livestock pressure, the piping is switched and the normal gas is blown. . When the ladle is moved after the gas is blown, the gas stored in the tank has a function of being supplied to the gas blowing plug and suppressing the permeation of the molten metal into the gas blowing plug. (Operation) Gas is supplied by the gas supply source connected to the pipe connection portion (gas cylinder side) 8b in FIG. 2, and the check valve (gas cylinder entry side) 5b is passed through and the pressure is stored in the gas cylinder 3. At this time, in the shuttle valve 7, the supply pressure from the gas cylinder 3 is higher than the pressure in the gas blowing pipe 9,
The circuit is such that the gas from the gas cylinder 3 is supplied to the gas blowing plug 2. Next, the pipe is reconnected to the pipe connecting portion (gas blowing side) 8a so that the gas is supplied to the gas blowing pipe 9. The shuttle valve 7 is switched because the pressure of the gas blowing pipe 9 is higher than the pressure of the gas cylinder 3 side, the circuit on the gas cylinder 3 side is closed, the circuit between the gas blowing pipe 9 and the pipe 6 is opened, and the gas cylinder 3 is closed. The gas blowing operation is performed under the pressure of storage. After the gas is blown, the gas supply source connected to the pipe connecting portion (gas blowing side) 8a is disconnected, and when the gas supply is stopped, the pressure in the gas cylinder 3 becomes higher than the pressure in the gas blowing pipe 9. Therefore, the shuttle valve 7 is switched, the circuit from the gas cylinder 3 to the pipe 6 is opened, and the circuit from the gas blowing pipe 9 to the pipe 6 is closed. As a result, the gas stored in the gas cylinder 3 is throttled to a specified flow rate by the on-off valve (also serving as a throttle valve) 4 through the check valve (gas cylinder outlet side) 5a and supplied to the gas blowing plug 2.

[0008]

[Embodiment] The operation of the circuit described in the above section (action) in actual use will be described. The gas supply source (source pressure 7) connected to the pipe connection portion (gas cylinder side) 8a in FIG.
Gas is supplied by ₂ ), and the gas is first stored in the gas cylinder 3. Next, the pipe is reconnected to the pipe connecting portion (gas blowing side) 8a, the circuit of the gas blowing pipe 9 and the pipe 6 is opened,
The gas blowing operation is performed in a state where the pressure is stored in the gas cylinder 3. And after the gas is blown, the pipe connection (gas blow side)
When the gas supply source connected to 8a is disconnected and the gas supply is stopped, the gas stored in the gas cylinder 3 flows through the check valve (gas cylinder outlet side) 5a at the on-off valve (also used as the throttle valve) 4 at the specified flow rate. And is supplied to the gas blowing plug 2, and gas is blown even during movement.

[0009]

As described above, according to the present invention, in the ladle for molten metal, by using the gas cylinder and the special circuit for accumulating the gas, the gas compressed by the gas cylinder is blown even when the gas is moving. It has become possible to suppress the penetration of molten metal into the gas-blowing plug by supplying it to the plug. Therefore, the gas blowing plug can be reused and the number of times of use can be improved.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view of a conventional ladle for molten metal.

FIG. 2 is a vertical sectional side view showing an embodiment of the present invention.

[Explanation of symbols]

 1 Molten metal ladle 2 Gas blow plug 3 Gas cylinder 4 Open / close valve (also used as throttle valve) 5a Check valve (gas cylinder outlet side) 5b Check valve (gas cylinder inlet side) 6 Piping 7 Shuttle valve 8a Piping connection (gas blowing) Side) 8b Piping connection (gas cylinder side) 9 Gas blowing piping

Claims (1)

[Claims] 1. A ladle for molten metal having a gas blowing plug for blowing a stirring gas at the bottom, in order to prevent penetration of metal into the gas blowing plug when the ladle is moved, a gas cylinder for livestock pressure. And a ladle for molten metal, which is composed of two circuits, a circuit for performing storage pressure and a circuit for normal gas blowing, and which is switched by replacing the piping.