JPH09314313A - Ladle for molten metal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To restrain the penetration of molten metal into a gas blowing plug at the time of moving a ladle and then, to improve the reuse and use frequencies of the gas blowing plug by executing pressure accumulation exceeding the pressure caused by the wt. of molten metal in a ladle with a gas cylinder and blowing gas in small portion even at the time of shifting. SOLUTION: In the ladle 1 for molten metal having the gas blowing plug 2 for bottom-blowing the stirring gas at the bottom part, the gas cylinder 3 for pressure accumulation and a circuit for executing the pressure accumulation therein to prevent the penetration of the metal into the gas blowing plug 2 at the time of moving the ladle are provided. The gas accumulated with pressure is supplied into the gas blowing plug with the gas cylinder even at the time of movement by using the gas cylinder and the special circuit for accumulating the pressure into this cylinder and then, the penetration of the molten metal into the gas blowing plug can be restrained. Therefore, the reuse and the improvement of use frequencies of the gas blowing plug are realized.

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, which does not blow gas when the ladle is moved. 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, in the method shown in FIG. 1, a gas blowing plug 2 which is buried in the bottom of a ladle for molten metal 1 and blows a gas onto the molten metal in the ladle is used to move the ladle after the gas blowing process. When doing so, to disconnect and move the gas pipes,
When moving, the molten metal entered the inside of the gas blow plug 2, and even when it was tried to use it again, it was often impossible to use because it was blocked inside the plug. for that reason,
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.
(Utility model application, Sho 64-15656) However, even when this technique is used, the storage pressure in the gas cylinder 3 is not exerted, the effect is not so great, and the penetration of the molten metal has not been suppressed.

In a conventional ladle for molten metal 1 equipped with a gas cylinder 3, a high-pressure gas normally passes through the cylinder during gas blowing, and the molten metal does not enter the gas blowing plug 2, but moves. At times, when the high-pressure gas is disconnected, the gas stored in the cylinder is moved to the place where the gas is stored only to the same level as the pressure at the bottom of the ladle due to the molten metal in the ladle. Since the gas in the gas blowing plug 2 flows upward due to the difference in specific gravity, the effect of suppressing the permeation of the molten metal is weakened with time, and finally the molten metal permeates into the gas blowing plug 2. It is thought to go. For this reason, there has been a need for a technique that enables the storage pressure in the gas cylinder 3 to be higher than the pressure due to the molten metal in the ladle.

[0004]

SUMMARY OF THE INVENTION In the method of FIG. 1 described above,
Since the storage pressure exceeding the pressure generated by the specific gravity of the molten metal in the ladle cannot be performed in the gas cylinder 3, the permeation of the molten metal into the gas blowing plug 2 cannot be sufficiently suppressed when the ladle is moved, and the gas blowing plug 2 It was difficult to reuse the gas blowing plug 2 because the flow rate of the gas blowing plug was reduced and finally closed.

Molten metal gas blowing plug 2 when moving the ladle
In order to suppress the infiltration into the inside, if the storage pressure exceeding the pressure generated by the specific gravity of the molten metal in the ladle can be performed in the gas cylinder 3 and the gas can be blown little by little even when moving, It is possible to suppress the permeation of the molten metal into the gas blowing plug 2 when the ladle is moved.

The present invention has been made in order to meet the above-mentioned demands, and enables a storage pressure exceeding the pressure generated by the specific gravity of the molten metal in the ladle to be generated in the gas cylinder 3, and a small amount even during movement. By allowing the gas to blow one by one, it is intended to suppress the permeation of the molten metal into the gas blowing plug 2 when the ladle is moved, and thereby to reuse the gas blowing plug 2 and improve the number of times of use.

[0007]

According to the present invention, in the initial stage of gas blowing according to the method of FIG. 2, forcibly pressure is applied to the inside of the gas cylinder 3, and after the end of the pressure, the safety valve opens and the normal gas is blown. I do. When the ladle is moved after the gas is blown, the gas stored in the tank is supplied to the gas blowing plug 2 and has a function of suppressing the permeation of the molten metal into the gas blowing plug 2.

[0008]

The gas is supplied from the gas supply source connected to the pipe connecting portion 10 in FIG. 2, and is initially stored in the gas cylinder 3 through the safety valve (gas cylinder inlet side) 7b. Next, when the pressure inside the gas cylinder 3 reaches the safety valve (gas cylinder outlet side gas blowing side) 7a valve switching pressure, gas is supplied to the pipe 6 and gas is blown in the gas cylinder 3 in a pressure-stored state. Take action. After the gas is blown, the gas supply source connected to the pipe connection portion 10 is disconnected, and when the gas supply is stopped, the pressure in the gas cylinder 3 depends on the pressure of the safety valve (gas cylinder outlet side gas blow side) 7a and the molten metal. Gas is supplied from the gas cylinder 3 until it becomes lower than the sum of the back pressures. Then, when the pressure in the gas cylinder 3 becomes equal to or lower than the set pressure of the back pressure + 7a by the molten metal, the safety valve (gas cylinder outlet side gas blowing side) 7a is closed to maintain the pressure and prevent the molten metal from permeating.

[0009]

[Examples]

The operation of the circuit described in the item [Operation] during actual use will be described. Gas is supplied by a gas supply source (source pressure 7 kg / cm ² ) connected to the pipe connection portion 10 in FIG. 2, and is first stored in the gas cylinder 3 via the safety valve (gas cylinder entry side) 7 b. Next, the pressure inside the gas cylinder 3 is set to a safety valve (gas cylinder outlet side, gas blowing side) 7a (normally 0.
When the set pressure of (5 kg / cm ² ) + the back pressure due to the molten metal is equal to or higher than the set pressure, the safety valve (gas cylinder outlet side, gas blow side) 7a opens, and gas blow operation is performed with the gas cylinder 3 being under pressure. . After the gas is blown, the gas supply source connected to the pipe connection portion 10 is disconnected, and when the gas supply is stopped, the gas stored in the gas cylinder 3 becomes the pressure of the safety valve (gas cylinder outlet side gas blow side) 7a. Gas is supplied from the gas cylinder 3 until it becomes lower than the sum of the back pressures of the molten metals. When the pressure in the gas cylinder 3 becomes equal to or lower than the set pressure of the back pressure of molten metal + 7a, the safety valve (gas cylinder outlet side gas blowing side) 7a is closed and the pressure is maintained,
Prevents penetration of molten metal.

[0010]

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 Ladle for molten metal 2 Gas blow plug 3 Gas cylinder 4 Open / close valve (also used as throttle valve) 5 Check valve 6 Piping 7a Safety valve (gas cylinder outlet side Gas blowing side) 7b Safety valve (gas cylinder inlet side) 8 Gas blowing pipe (gas cylinder) Outlet side) 9 Gas blowing pipe (gas cylinder inlet side) 10 Piping connection

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 has a circuit for performing livestock storage there.