JPS5823481Y2 - sliding nozzle device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a means for supplying gas into the injection hole of a sliding nozzle device installed in a ladle or a tundish for continuous casting.

For sliding nozzle devices of ladles or continuous casting tundishes (・In order to prevent the solidification of molten metal inside the nozzle,
Inert gas is blown into the nozzle hole in order to stir the molten metal in the container, prevent the nozzle from clogging due to deposits on the inner surface of the nozzle, and clean the molten metal. When injecting from the upper nozzle or upper fixed plate, a hole with several diameters is provided directly to the injection hole, or a gas-permeable refractory ring is installed on the inner surface of the injection hole and connected to this. Gas is blown into the injection hole by drilling introduction holes and connecting gas supply pipes to these holes.

Also, when blowing gas from the lower sliding plate,
Gas is mainly injected to prevent the molten metal from coagulating within the nozzle hole diameter or to stir the molten metal in the container, but when the injection hole of the sliding nozzle device is closed, the lower Either provide holes or grooves with several hole diameters in the sliding plate part, or install a gas-permeable refractory molded body, connect it to this, drill a gas introduction hole, and connect the gas supply pipe to these. The gas is blown into the nozzle.

On the other hand, in a sliding nozzle device, during maintenance or operation, the upper nozzle or the upper and lower plates often crack due to stress such as thermal distortion, surface pressure between the upper and lower plates, or operational impact.

Therefore, in the sliding nozzle device configured as above, the gas introduced from the gas supply pipe flows in a direction with less ventilation resistance, so that most of the gas often leaks to the outside through the cracks. Gas injection into the injection hole was unstable.

The present invention relates to an improvement of a gas blowing means to solve the above-mentioned drawbacks and to enable stable gas blowing. A hole with a diameter of 1/2-3/io of the thickness of the plate is drilled in the center toward the injection hole, a gas-permeable refractory molded body is fitted to the tip of the metal cylinder, and the rear end is This is a sliding nozzle device in which a gas supply cylinder having a connecting end and a gas supply hole with a small cross section in the middle thereof is fitted and fixed in the hole of the upper fixing plate.

That is, the present invention provides a method for supplying gas from the upper fixed plate portion of the sliding nozzle device to the injection hole.
The present invention provides a sliding nozzle device equipped with a gas supply system that prevents gas from leaking out of the system even if a crack occurs in the plate.

Hereinafter, the device of the present invention will be explained based on examples.

FIG. 1 is an explanatory longitudinal cross-sectional view of a sliding device according to the present invention.

In the figure, 1 is a refractory wall forming the bottom of a ladle or a tundish for continuous casting.

Reference numeral 2 denotes an upper nozzle mounted on the nozzle freezing tile 3, and below the upper nozzle 2, an upper fixed plate 4, a lower sliding plate 5, and a lower nozzle 6 are installed, respectively.

FIG. 1 shows a state in which the upper nozzle 2 and the lower nozzle 6 are communicated with each other, and molten steel, for example, is supplied through the injection hole I.

The gas guided by the gas supply pipe 8 connected to a gas supply source (not shown) is passed through the gas supply cylinder 10 fitted into the hole 9 formed in the upper fixed plate 4. and is blown into the injection hole 7.

FIG. 2 is an enlarged sectional view of the upper fixing plate 4, and FIG. 3 is a plan view of the upper fixing plate 4.

As shown in the figure, a hole 9 is bored in the approximate center of the upper fixing plate 4 in the thickness direction toward the injection hole 7 .

The diameter of the hole 9 is 4 to 10' of the thickness of the upper fixing plate 4.
That is.

The larger the diameter of this hole 9, the more gas can be blown into it, but it is set to be smaller than the thickness of the upper fixed plate 4 so as not to significantly impair the strength of the upper fixed plate 40.

On the other hand, if the holes 9 become too small, it becomes difficult to secure the necessary amount of gas blown.

Therefore, the lower limit is the plate 40k.

up to. No matter how small the hole 9 may be in the upper fixing plate 4, it reduces the strength of the plate, so it is desirable that the length of the hole 9 be as short as possible.

The shortest distance is in the direction perpendicular to the sliding direction (arrow 17) of the sliding plate 5 with the injection hole 7 as the starting point. Since the sliding direction (arrow 17) is the starting point and the direction perpendicular to the sliding direction, the hole 9 shown by the dotted line should be drilled in a position that avoids this part, for example, in the direction shown in Figure 3. is desired.

A gas supply cylinder 10 having the configuration described below is fitted into the hole 9 of the upper fixing plate 4.

The gas supply cylindrical body 10 shown in FIG.
The cylindrical body 11 has a connecting end 13 formed of a flange at its rear end, and a gas supply hole 14 having a small cross section in the middle of the cylindrical body 11.

As the gas permeable refractory molded body 12, a molded body in which pores are formed in a refractory composition such as alumina, zircon, silicon carbide, carbon, etc., which has high corrosion resistance and is difficult to wet with molten metal such as molten steel, is suitable.

The pores may be non-directional or may have pores aligned in one direction.

In any case, the smaller the porosity, the less likely it is that molten metal will penetrate, but the gas ventilation resistance will increase.

Therefore, the gas-permeable refractory molded body 1 has arbitrary properties based on the relationship between the required amount of blown gas 9 and the diameter of the holes 9.
2 is selected.

The molded body 12 is formed into a cylindrical shape, and a film 15 coated with glaze and fired is formed on the outer surface of the body.

When fitting the molded body 12 to the tip of the metal cylindrical body 11, a refractory material having an adhesive function such as mortar is interposed.

If the proportion of the length of the molded body 12 within the cylindrical body 11 is too large, ventilation resistance will increase.

On the other hand, if it is too small, it will be difficult to securely hold the molded body 12 at the tip of the cylindrical body 11.

When the molded body 12 is short, a tapered portion 16 is provided at the tip of the molded body 12 as shown in FIG. There are means such as making the tip of the cylindrical body 11 narrow.

Incidentally, the connection end 13 is shown as a screw type.

A gas supply hole 14 with a small cross section is provided midway between the tip of the cylinder 11 and the connecting end 13. This prevents problems in which molten metal may flow out due to druffles such as damage.

When fitting the gas supply cylinder 10 configured as described above into the hole 9 of the upper fixing plate 4, mortar is applied to the outer circumference of the cylinder 10, and the gap between the hole 9 and the cylinder 100 is closed. Fill.

Since the sliding nozzle device according to the present invention is constructed as described above, gas can be injected into the injection hole T at any time when the injection hole T is open or when it is blocked by the sliding plate 5. Can be injected.

In addition, in the present invention, the gas supply cylinder 10 is fitted into the hole 9 provided in the upper fixing plate 4, so even if cracks occur in the upper fixing plate 4 during use, the gas to be supplied will continue to flow. Since it is difficult for the gas to flow out of the system, gas can be smoothly blown into the injection hole 7 during the life of the upper fixed plate 4.

[Brief explanation of the drawing]

Fig. 1 is an explanatory longitudinal cross-sectional view of a sliding nozzle device according to the present invention, Fig. 2 is an explanatory enlarged cross-sectional view of the main part of the present invention, and Fig. 3
This figure is an explanatory plan view of the upper fixing plate, and FIG. 4 is an explanatory view of another embodiment of the main part of FIG. 2. In the figure, 1 is a fireproof wall, 2 is an upper nozzle, 3 is a nozzle receiving brick,
4 is an upper fixed plate, 5 is a lower sliding plate, 6 is a lower nozzle, 7 is an injection hole, 8 is a gas supply pipe, 9 is a hole, 10 is a gas supply cylinder, 11 is a metal cylinder, 12 is a gas A permeable fireproof molded body, 13 is a connection end, 14 is a gas supply hole, 15 is a glaze film, 16 is a tapered part, and 17 is a sliding direction.

Claims (1)

[Scope of utility model registration request] In the sliding nozzle, at approximately the center of the upper fixed plate in the thickness direction, there is a
A hole with a diameter of 2 to 'i0 is bored, a gas-permeable refractory molded body is fitted to the tip of the metal cylinder, and a connecting end is provided at the rear end, with a small cross-section gas supply in the middle. A sliding nozzle device in which a gas supply cylinder having a hole is fitted and fixed into a hole in the upper fixing plate.