JPH09277030A - Device for removing clogging of nozzle for discharging molten steel in ladle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To open the hole in a nozzle by removing plugging material without oxidizing molten steel, at the time of developing the clogging of the nozzle fitted to the bottom part of a ladle. SOLUTION: A nozzle clogging removal device is provided with an air sealing pipe 11 fitted to a collector nozzle 3d in the nozzle 3 fitted to the bottom part of the ladle 1, a nozzle closing plug device 12 fitted to the air sealing pipe and a gas supplying device 13 for supplying inert gas in the nozzle closing plug device. The nozzle closing plug device is provided with a fixed pipe 21 fitted to the air sealing pipe, a slide pipe 22 slidingly elevated in the fixed pipe by receiving gas supplied pressure, a bag closing plug 24 fitted to the tip end side of the slide pipe and communicated with the inner part of the slide pipe and a heat resistant breaking plate for breaking a part thereof at the time of receiving a prescribed pressure. The gas supplying device is the one for supplying the inert gas having two kind of the gas supplying pressures of a prescribed gas supplying pressure for elevating the slide pipe without breaking the breaking plate and a prescribed gas supplying pressure for breaking the breaking plate into the fixed pipe in the nozzle closing plug device.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nozzle opening / closing device mounted at the bottom of a ladle used for steelmaking in a steel mill to stop the discharge of molten steel. The present invention relates to a nozzle clogging removal device for removing ladle molten steel to be removed.

[0002]

2. Description of the Related Art FIG. 8 is a longitudinal sectional view showing a state in which a nozzle of a conventional nozzle opening / closing device attached to the bottom of a ladle is filled with sand, and FIG. 9 is a cleaning for removing the nozzle blockage in the nozzle opening / closing device. It is a longitudinal cross-sectional view showing a state in which an oxygen pipe for use is attached. In FIG. 8, a nozzle opening / closing device for stopping the discharge of the molten steel 2, that is, a rotary nozzle 3 is attached to the bottom of the ladle 1. This rotary nozzle 3 is the upper nozzle 3
a, a bottom plate 3b (fixed plate), a slide plate 3c (sliding plate), and a collector nozzle 3d. When the ladle 1 receives the molten steel 2, the slide plate 3c of the rotary nozzle 3 is closed as shown in FIG. 8, sand 4 is charged from the inner upper part of the ladle 1, and the upper nozzle is moved from the slide plate 3c. The nozzle holes 3e up to 3a are filled with sand 4, and in this state, the molten steel 2 is received from the converter. When the molten steel 2 in the ladle 1 is discharged to the casting tundish 6, an air seal pipe (not shown) is attached to the collector nozzle 3d of the rotary nozzle 3 and the slide plate 3c is opened to cast the molten steel 2 Discharge to tundish 6.

However, even if the slide plate 3c is opened, the molten steel 2 may not be discharged due to the clogging of the clogging material 5 due to the previously introduced sand 4 or the solidified material of the molten steel 2. In such a case, conventionally, as shown in FIG. 9, the air seal pipe is removed from the rotary nozzle 3, and the end of the cleaning oxygen pipe 8 bent in an L shape is inserted from the lower end of the collector nozzle 3d of the rotary nozzle 3. The nozzle hole 3e is inserted upward, and oxygen is supplied from the operating side to ignite the oxygen to clean the nozzle holes 3e. A technique similar to the oxygen cleaning method using such a cleaning oxygen pipe 8 is disclosed in Japanese Utility Model Publication No. 59-135859, JP-A-6-328.
No. 231 publication. In addition, Japanese Examined Japanese Patent Sho 60-1
In the method for opening the molten metal container disclosed in Japanese Patent No. 59590, a gas generating substance is enclosed in the cylinder, and when the molten metal in the hot water discharge passage is caused to flow out, the gas is generated in the cylinder. The piston of the cylinder is raised by the pressure to open the sealing plug that closes the hot water discharge passage.

[0004]

A conventional oxygen cleaning method using the cleaning oxygen pipe 8 shown in FIG. 9 is used, JP-B-59-135859 and JP-A-6-32823.
In any case, the one disclosed in Japanese Patent No. 1 has a problem that the molten steel at the initial stage of tapping is oxidized because the tapping is performed in an oxygen atmosphere, resulting in deterioration in quality. In addition, Tokiko Sho 6
The method for opening the molten metal storage container disclosed in Japanese Patent Laid-Open No. 0-159590 requires a treatment of setting a tight-fitting plug and a cylinder in which a gas generating substance is sealed, and since they are disposable, compared with the conventional oxygen cleaning method. There was also a problem that the cost would increase. Further, even if such a method is implemented, there is a problem that it is practically difficult to set a blockage inside the pot and to support the thrust of the cylinder. The present invention has been made to solve such a problem, and is a method similar to a conventional method used only when a nozzle attached to the bottom of a ladle is clogged, in order to remove a clogging material without oxidizing molten steel. It is an object of the present invention to provide a nozzle clogging removal device for discharging ladle molten steel that removes and opens a nozzle.

[0005]

A nozzle clogging removal device for discharging ladle molten steel according to the present invention is provided with an air seal pipe attached to a collector nozzle of a nozzle attached to the bottom of a ladle, and an air seal pipe. The nozzle sealing plug device is provided with a gas supply device for supplying an inert gas to the nozzle sealing plug device, and the nozzle sealing plug device has a fixed pipe mounted in the air seal pipe and a gas supply pressure in the fixed pipe. It has a slide pipe that receives and slides up, a sealing plug attached to the tip end side of the slide pipe, and a heat-resistant pressure adjusting means that is attached to the lower end of the slide pipe and opens when a predetermined pressure is applied. , The gas supply device raises the slide pipe without opening the pressure adjusting means to the fixed pipe of the nozzle sealing stopper device, and opens the predetermined gas supply pressure and pressure adjusting means. It is configured to supply two gas inert gas supply pressure to a predetermined gas supply pressure.

Further, the above-mentioned sealing plug is a bag sealing plug which communicates with the inside of the slide pipe and expands by a predetermined gas supply pressure for opening the pressure adjusting means. Further, both ends of the bag sealing plug are covered with a cover formed of a heat-resistant cloth for both heat insulation and reinforcement.

A pressure receiving packing is provided between the lower end of the slide tube and the pressure adjusting means and has a hole in the center thereof, the outer peripheral surface of which slides in close contact with the inner peripheral surface of the fixed tube. ing.

In the nozzle clogging removal device for discharging ladle molten steel according to the present invention, an air seal pipe equipped with a nozzle sealing plug device is attached to the lower end of the nozzle attached to the bottom of the ladle, and the gas supply device seals the nozzle. When an inert gas having a predetermined gas supply pressure that raises the slide pipe without supplying the pressure adjusting means to the fixed pipe of the stopper device is supplied, the slide pipe integrated with the pressure adjusting means that receives the gas supply pressure moves inside the fixed pipe. The slide tube rises and stops when the sealing plug attached to the tip side of the slide tube hits the blockage in the nozzle, and the gas supply device opens the pressure adjusting means to the fixed pipe of the nozzle sealing plug device. When an inert gas having a predetermined gas supply pressure is supplied, the pressure adjusting means receiving the gas supply pressure is opened, and the inert gas passes through the inside of the slide pipe, Inert gas is injected from the tip of the ride pipe into the closed portion between the sealing plug and the blockage in the nozzle to damage the blockage in the nozzle by the gas supply pressure, and the nozzle is opened in the atmosphere of the inert gas. Therefore, the nozzle can be opened in an atmosphere of an inert gas, and a slab of quality with no quality problem can be produced immediately after the opening, and the casting yield is improved. In addition, the gas leaking during the opening operation can be effectively used as a replacement gas for keeping the inside of the tundish in an unoxidized state. Further, the nozzle sealing plug device is attached to the air seal pipe, and the nozzle is opened with the air seal pipe attached to the nozzle, so that the molten steel discharge can be continuously performed without stopping after completion of the opening. The operation can be continued for a long time, and it is possible to prevent a decrease in production capacity and a change in the production process.

Further, since the sealing plug is a bag sealing plug which communicates with the inside of the slide pipe and expands by a predetermined gas supply pressure for opening the pressure adjusting means, the entire nozzle sealing plug device is lighter than the case of the sealing plug. It is easy to attach the nozzle sealing plug device to the air seal pipe. Further, since both ends of the bag sealing stopper are covered with a cover formed of a heat resistant cloth that also serves as heat insulation and reinforcement,
Even if it takes some time to break the blockage in the nozzle due to the gas supply pressure, the bag sealing plug itself is not damaged, and the nozzle can be reliably opened.

A pressure receiving packing is provided between the lower end of the slide tube and the pressure adjusting means and has a hole in the center thereof, the outer peripheral surface of which slides in close contact with the inner peripheral surface of the fixed tube. Therefore, when the gas supply device supplies an inert gas with a predetermined gas supply pressure that raises the slide pipe to the fixed pipe of the nozzle sealing plug device, the pressure supply packing reliably receives the gas supply pressure and the slide pipe Will efficiently rise in the fixed tube.

[0011]

1 is a longitudinal sectional view showing a ladle equipped with a ladle molten steel discharging nozzle clogging removal device according to the present invention, and FIG. 2 is a partially omitted perspective view showing a nozzle sealing device.
FIG. 3 is a sectional view showing the nozzle sealing plug device, and FIG. 4 is a sectional view showing the operating condition of the sealing plug of the nozzle sealing plug device in order from the left.
5 is a cross-sectional view showing a part of the operating state of the sealing cap of the nozzle sealing plug device, FIG. 6 is a gas supply piping system diagram for supplying gas to the nozzle sealing plug device, and FIG. 7 is gas supplying to the nozzle sealing plug device. It is a diagram showing a pressurization pattern of. In the figure, the same configurations as those of the conventional example are denoted by the same reference numerals, and the description of the duplicate configurations is omitted. The nozzle clogging removal device for discharging ladle molten steel according to the present invention is an air seal pipe 11, a nozzle sealing plug device 12 mounted on the air seal pipe 11, and a gas supply device for supplying an inert gas to the nozzle sealing plug device 12. Thirteen
It is composed of The air seal pipe 11 is attached to the collector nozzle 3d of the rotary nozzle 3,
This is for guiding the molten steel 2 to the casting tundish 6.

The nozzle sealing plug device 12 is for removing the clogging material 5 such as the solidified material in the nozzle hole 3e of the rotary nozzle 3. The nozzle sealing plug device 12 has a telescopic double tube structure including an outer tube and an inner tube, and has a fixed tube 21 which is an outer tube mounted in the air seal pipe 11 and a gas pressure in the fixed tube 21. It covers the slide tube 22 that is an inner tube that receives and slides up, and the bag stopper attachment rod 23 connected to the tip end of the slide tube 22, and both ends of the band 2
A bag sealing plug 2 made of heat-resistant silicon rubber, for example, which is tightened by 4a and attached to the bag stopper mounting rod 23.
4, a heat-resistant pressure-receiving packing 25 that is concentrically attached to the lower end of the slide tube 22 and has a hole at the center position that seals the gap with the fixed tube 21, and between the pressure-receiving packing 25 and the lower end surface of the slide tube 22. The rupture plate 26 is a heat-resistant pressure adjusting means that is mounted and opens when a constant pressure is applied.

The bag plug mounting rod 23 has a first communicating hole 23a at the lower end thereof for communicating the slide tube 22 and the bag sealing plug 24, and an upper end for communicating the bag sealing plug 24 with the outside. It has the 2nd communicating hole 23b which makes it. In order to ensure that the bag sealing plug 24 has a bag-like shape, the second communication hole 23b is provided with the first communication hole 23b so that the pressure inside the bag sealing plug is slightly higher than the pressure on the bag cap outlet side. The hole is slightly smaller than the communication hole 23a. 27 is a cover made of a heat-resistant cloth that covers both end sides of the bag sealing plug 24 and also serves as heat insulation and reinforcement of the bag sealing plug 24, and 28 is a radial support rod that is attached to the end of the fixed tube 21 and gradually expands. Thus, the expanding end portion has an outward engaging flange 28a. 29 is a fixed tube 21
It is an iron plug storage cylinder that is attached to the end of the support and is located inside the support 28 to store the bag sealing plug 24.

The gas supply device 13 is a nozzle sealing plug device 12
To supply an inert gas such as argon gas (hereinafter referred to as Ar gas). Reference numeral 14 is a gas supply source valve provided between the gas supply device 13 and the inert gas supply source 15. This gas supply device 13
Is a pressure reducing valve 31 connected to the gas source valve 14,
A first check valve 32 connected to the pressure reducing valve 31, a second check valve 33 connected to the first check valve 32, and an electromagnetic switching valve connected to the second check valve 33. 34 and electromagnetic switching valve 34
A gas supply hose 35 that connects the fixed pipe 21 of the nozzle sealing plug device 12 to each other, a compressor 36 that is connected to the input side and the output side of the first check valve 32, and a motor 37 that drives the compressor 36. A pressure detection controller 38 is provided which detects the pressure of the gas flowing through the gas supply hose 35 and outputs a drive control signal to the electromagnetic switching valve 34 and the motor 37 in accordance with the detected gas pressure.

Next, the operation of the ladle molten steel discharging nozzle clogging removing device of the present invention will be described with reference to FIGS. As shown in FIG. 4 (a), the ladle 1 is used to start casting.
A casting tundish (not shown) is set underneath, and as shown in FIG.
If the molten steel 2 does not come out due to nozzle clogging even if the rotary nozzle 3 to which is attached is opened, the air seal pipe 11 is removed, and the air seal pipe 11 with the nozzle sealing device 8 of the present invention set is attached to the rotary nozzle 3 Attach to. The nozzle sealing plug device 8 is set to the air seal pipe 11 by hooking the hooking flange 28a of the support 28 attached to the fixed pipe 21 to the inner edge of the air seal pipe 11 to fix the hooking flange 28a. When the hooked air seal pipe 11 is mounted on the collector nozzle 3d, the hooking flange 28a is fixed by being attached to the air seal pipe 11 and the collector nozzle 3d. When the nozzle sealing plug device 8 is set on the air seal pipe 11 in this manner, the gas supply hose 35 of the gas supply device 13 connected to the gas supply source 15 via the gas supply source valve 14 is connected to the nozzle sealing plug device 12.
It is used by the following operation by connecting to the fixed tube 21 of.

First, as shown in FIG. 4 (c), when the rotary nozzle 3 is opened and the gas supply valve 14 is gradually opened, the Ar gas from the gas supply source 15 is reduced by the pressure reducing valve of the gas supply device 13. The first check valve 32, the second check valve 33, the electromagnetic switching valve 34, and the gas supply hose 35 reach the fixed pipe 21 of the nozzle sealing plug device 12. When the gas supply pressure of the Ar gas received by the rupture plate 26 in the fixed tube 21 increases, as shown in FIG. 4D, the rupture plate 26, the slide tube 22 and the bag stopper mounting rod 23 are integrally sealed in a bag. Stopper 24
Moves up in the nozzle hole 3e, and the upper end of the bag stopper attachment rod 23 hits the blockage 5 in the nozzle hole 3e, or stops rising at the slide rising limit. At this time, the bag stopper mounting rod 23
The second communication hole 23b at the upper end of is closed. Furthermore, A
When the pressure of the gas supply pressure of the r gas continues to increase, the gas supply pressure in the fixed pipe 21 below the slide pipe 22 rises, and eventually the rupturable plate 26 bursts at its central portion. Then, Ar gas enters the slide tube 22 and reaches the sealing plug 24 through the first communication hole 23a of the bag plug mounting rod 23. Then, as shown in (e) of FIG.
4 expands and closes the nozzle hole 3e. At this time, a sealed portion is formed between the obstruction 5 and the bag sealing plug 24.

When the Ar gas is further supplied in this state, the Ar gas is jetted from the second communication hole 23b at the upper end of the bag stopper mounting rod 23 as shown in FIG. The space between the bag sealing plug 24 and the obstruction 5 in 3e is pressurized, so that the obstruction 5 is destroyed. Then, the molten steel 2 in the ladle 1 pushes back Ar gas, and the molten steel 2 flows out into the air seal pipe 11. In this state, the main valve 14 of the gas supply device 13 is closed, and the opening work is completed. The nozzle hole 3e of the rotary nozzle 3 is opened in the non-oxidized state by the above method. It should be noted that due to the pressurization, a force is generated in the bag sealing plug 24 in the direction of withdrawal. The gas supply pressure is proportional to the escape force. On the other hand, if the gas supply pressure increases, the pressure with which the bag sealing plug 24 pushes against the wall also increases, making it difficult to escape. That is, since the frictional force for suppressing the escape also increases / decreases in proportion to the increase / decrease in the gas supply pressure, the bag sealing plug 24 is fixed at the stop position regardless of the gas supply pressure.

As shown in FIG. 7A, the gas supply pressurization pattern described above gradually increases the pressure from zero pressure to a predetermined gas supply pressure P2 and holds the pressure for an arbitrary time. It is a pattern. In the second pattern, as shown in FIG. 7B, the pressure is increased from zero pressure, first to the predetermined first gas supply pressure P1, and then to the predetermined pressure with a pressure increase time earlier than the pressure increase time to P1. The pressure of P1 and P2 is increased by increasing the second gas supply pressure P2, then reducing the pressure to zero, then increasing again to P1, then increasing to P2, and then reducing to zero. This is a pattern in which depressurization is repeated. In this first gas supply pressurization pattern, the pressure reducing valve 31 is set to the first gas supply pressure P1, and the pressure detection controller 38 outputs an ON signal to the motor 37 when detecting the first gas supply pressure P1. When the second gas supply pressure P2 is detected, an OFF signal is output to the motor 37, and an ON signal is output to the electromagnetic switching valve 34 after a predetermined time. Therefore, when the gas source valve 14 is opened, the gas supply pressure gradually rises, and the inert gas source 1
Even if the gas supply pressure of 5 is P1 or more, the pressure reducing valve 31 reduces the pressure and maintains the gas supply pressure of P1.

When the pressure detection controller 38 detects that the gas supply pressure of the Ar gas flowing through the gas supply hose 35 is P1, it outputs an ON signal to the motor 37, and the compressor 37 is driven by driving the motor 37. Then, the pressure of the gas supplied to the electromagnetic switching valve 34 is increased. And
When the pressure detection controller 28 detects that the gas supply pressure of the gas supply hose 35 is P2, it outputs an off signal to the motor 37 to stop the motor 37 and stop the operation of the compressor 36. Since the second check valve 33 is provided even when the compressor 36 stops operating, the gas supply hose 3
The gas supply pressure of 5 is maintained at P2. When the pressure detection controller 38 detects the second gas supply pressure P2, it outputs an ON signal to the electromagnetic switching valve 34 after a predetermined time, so that the electromagnetic switching valve 34 performs a switching operation to open to the atmosphere and supplies the gas. The gas supply pressure of the hose 35 becomes zero pressure. This first gas supply pressurization pattern is applied when the blockage 5 is soft, the blockage 5 is destroyed, and the clogging of the nozzle hole is eliminated.

In the second gas supply pressurization pattern, the pressure reducing valve 31 is set to the first gas supply pressure P1, and the pressure detection controller 38 detects the first gas supply pressure P1 and outputs an ON signal to the motor 37. When the second gas supply pressure P2 is detected, an OFF signal is output to the motor 37, an ON signal is output to the electromagnetic switching valve 34, and an OFF signal is output to the electromagnetic switching valve 34 when zero pressure is detected. It is set. Therefore, when the gas supply source valve 14 is opened, the gas supply pressure gradually rises, and even if the gas supply pressure of the inert gas supply source 15 is P1 or more, the pressure reducing valve 21 reduces the pressure to maintain the gas supply pressure of P1. To do.

When the pressure detection controller 38 detects that the gas supply pressure of the gas supply hose 35 is P1, it outputs an ON signal to the motor 37, and the compressor 37 is driven by the drive of the motor 37 to electromagnetically switch. The gas supply pressure of Ar gas flowing through the valve 34 is increased. When the pressure detection controller 38 detects that the gas supply pressure of the gas supply hose 35 is P2, it outputs an off signal to the motor 37 to stop the motor 37 and stop the operation of the compressor 36. At the same time, when the pressure detection controller 38 detects the second gas supply pressure P2, it outputs an ON signal to the electromagnetic switching valve 34, so that the electromagnetic switching valve 34 performs a switching operation to open to the atmosphere and the gas supply hose 35. The gas supply pressure of is zero pressure.

When the pressure detection controller 38 detects zero pressure, it outputs an off signal to the electromagnetic switching valve 34.
The electromagnetic switching valve 34 performs a switching operation to stop opening to the atmosphere, the gas supply pressure of the gas supply hose 35 gradually increases, and the above-described operation is repeated. This second gas supply pressurization pattern is applied when the blockage 5 is less likely to be damaged, and the blockage 5 is destroyed by repeatedly pressurizing and depressurizing the gas, and the clogging of the nozzle hole is eliminated.

In all of the above-mentioned patterns, the static pressure of molten steel applied to the obstruction 5 is about ² to 3 kgf / cm ² ,
The pressure in the direction opposite to the molten steel static pressure applied to the block 5 by the device of the present invention is about ² to 6 kgf / cm ² , and the block 5 is sufficient.
Is destructible. Further, in this embodiment, the bag sealing plug 24 is used as the nozzle sealing means of the nozzle sealing device 12, but it is needless to say that it may be a solid sealing plug.

[0024]

As described above, according to the present invention, an air seal pipe equipped with a nozzle sealing plug device is attached to the lower end of a nozzle mounted on the bottom of a ladle, and a gas supply device serves as a fixed pipe of the nozzle sealing plug device. When an inert gas having a predetermined gas supply pressure that raises the slide tube without opening the pressure adjusting means is supplied, the slide tube integrated with the pressure adjusting means that receives the gas supply pressure rises in the fixed tube, The rise is stopped when the sealing plug attached to the tip side of the slide tube hits the blockage in the nozzle or at the slide rising limit, and the gas supply device further attaches a pressure adjusting means to the fixed pipe of the nozzle sealing plug device. When an inert gas having a predetermined gas supply pressure to be released is supplied, the pressure adjusting means that receives the gas supply pressure is opened, and the inert gas passes through the inside of the slide pipe and moves into the space. Inert gas is injected from the tip of the id tube into the sealing part between the sealing plug and the blockage inside the nozzle, the blockage inside the nozzle is damaged by the gas supply pressure, and the nozzle is opened in the atmosphere of the inert gas. As a result, the nozzle can be opened in an atmosphere of an inert gas, slabs of quality that can be produced without quality problems can be manufactured immediately after the opening, and the casting yield is improved. It has an effect that it can be effectively used also as a replacement gas for making the non-oxidized state.

Further, the nozzle sealing plug device is attached to the air seal pipe, and the nozzle is opened with the air seal pipe attached to the nozzle.
After the completion of the opening, the operation can be continued without stopping the molten steel discharge, and it is possible to prevent the production capacity from decreasing and the production process from changing. Further, since the sealing plug is a bag sealing plug that communicates with the inside of the slide pipe and expands by a predetermined gas supply pressure for opening the pressure adjusting means, the entire nozzle sealing plug device can be lighter than the case of the sealing plug, This has the effect of making it easier to attach the nozzle sealing plug device to the air seal pipe. Furthermore, since both ends of the bag sealing plug are covered with a cover formed of a heat-resistant cloth that also serves as both heat insulation and reinforcement, it takes some time for the blockage in the nozzle to be damaged by the gas supply pressure. However, there is no fear that the bag sealing plug itself will be damaged, and the nozzle can be surely opened.

A pressure receiving packing is provided between the lower end of the slide tube and the pressure adjusting means, having a hole in the center thereof, and the outer peripheral surface of which slides in close contact with the inner peripheral surface of the fixed tube. Therefore, when the gas supply device supplies an inert gas with a predetermined gas supply pressure that raises the slide pipe to the fixed pipe of the nozzle sealing plug device, the pressure supply packing reliably receives the gas supply pressure and the slide pipe Has the effect of efficiently rising in the fixed tube.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing a ladle to which a nozzle clogging removal device for discharging molten steel according to the present invention is attached.

FIG. 2 is a partially omitted perspective view showing a nozzle sealing plug device.

FIG. 3 is a cross-sectional view showing a nozzle sealing plug device.

FIG. 4 is a cross-sectional view showing an operating state of the sealing plug of the nozzle sealing plug device in order from the left.

FIG. 5 is a cross-sectional view showing a part of the operating state of the sealing plug of the nozzle sealing plug device.

FIG. 6 is a gas supply piping system diagram for supplying gas to the nozzle sealing plug device.

FIG. 7 is a diagram showing a pressurization pattern of gas supplied to the nozzle sealing device.

FIG. 8 is a vertical cross-sectional view showing a state in which the nozzle holes of a conventional nozzle opening / closing device attached to the bottom of a ladle are filled with sand.

FIG. 9 is a vertical cross-sectional view showing a state in which a cleaning oxygen pipe for removing nozzle clogging is attached to the nozzle opening / closing device.

[Explanation of symbols]

 1 Ladle 2 Molten Steel 3 Rotary Nozzle 3a Upper Nozzle 3b Bottom Plate 3c Slide Plate 3d Collector Nozzle 3e Nozzle Hole 5 Obstruction 6 Casting Tundish 11 Air Seal Pipe 12 Nozzle Sealing Plug Device 13 Gas Supply Device 14 Gas Supply Valve 15 Inert gas supply source 15 21 Fixed tube 22 Slide tube 24 Bag sealing plug (sealing plug) 26 Bursting plate (pressure adjusting means)

Claims (4)

[Claims] 1. An air seal pipe attached to a collector nozzle of a nozzle attached to the bottom of a ladle, a nozzle sealing plug device attached to the air seal pipe, and a gas supply for supplying an inert gas to the nozzle sealing plug device. The nozzle sealing plug device is equipped with a fixed tube mounted in the air seal pipe, a slide tube that slides up by receiving gas supply pressure in the fixed tube, and a tip end side of the slide tube. It has a sealing stopper and a heat-resistant pressure adjusting means that is attached to the lower end of the slide tube and opens when a predetermined pressure is applied. The gas supply device opens the pressure adjusting means to the fixed tube of the nozzle sealing stopper device. Inert gas having two kinds of gas supply pressures, that is, a predetermined gas supply pressure for raising the slide pipe and a predetermined gas supply pressure for opening the pressure adjusting means is supplied. Ladle molten steel discharge nozzle clog remover, characterized in that. 2. The nozzle for discharging ladle molten steel according to claim 1, wherein the sealing plug is a bag sealing plug that communicates with the inside of the slide pipe and expands by a predetermined gas supply pressure for opening the pressure adjusting means. Clog removal device. 3. The nozzle clogging removal device for discharging molten steel from a ladle according to claim 2, wherein both ends of the bag sealing plug are covered with a cover formed of a heat-resistant cloth for both heat insulation and reinforcement. . 4. A pressure-receiving packing having a hole in the central portion between the lower end of the slide tube and the pressure adjusting means, the outer peripheral surface of which slides in close contact with the inner peripheral surface of the fixed tube. The nozzle clogging removal device for discharging ladle molten steel according to claim 1, 2 or 3, characterized in that.