JPS6032924Y2 - Sealing device for immersion nozzle connection - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a sealing device for a connection part of a submerged nozzle used in continuous casting equipment and the like.

In order to produce high-quality products in continuous casting equipment, it is necessary to prevent the molten steel from coming into contact with air as much as possible and to prevent oxidation of the molten steel, which causes inclusions and pinholes. It has become common practice to use submerged nozzles.

However, if the connection part of the immersion nozzle is incompletely sealed, air will enter the molten steel flow and cause the product to be defective, so complete sealing of the connection part is required.

In order to satisfy these requirements, the present invention fills the area around the submerged nozzle connection with inert gas at a pressure slightly higher than atmospheric pressure, and even if the connection is not completely sealed, the inert gas This seals the flow of molten steel to prevent it from oxidizing.

Of course, in the past, various methods of sealing the submerged nozzle connection portion with inert gas have been considered, but each method has various disadvantages and shortcomings.

The conventional sealing method will be explained below for reference.

Figure 1 shows an overview of continuous casting equipment, where 1 is a ladle, 2 is a sliding nozzle for the ladle, 2' is its hydraulic cylinder, 3 is a tundish, 4 is a sliding nozzle for the tundish, and 4' is a hydraulic pressure cylinder. The cylinder, 5 is an immersion nozzle, 6 is a mold, 7 is a mold cover, and 8 is a slab.

Fig. 2 shows an example of a sealing method for the immersion nozzle connection in such continuous casting equipment. It supplies 17.

In this method, if the gas pressure and supply amount are sufficient, the purpose can be achieved remotely, but most of the supplied inert gas escapes into the atmosphere as shown by arrow 22, resulting in wasted gas. It has the disadvantage of being harsh.

Further, as illustrated in FIGS. 3 and 4, a cylindrical sealing mechanism is provided between the mold cover 7 and the spring 20.
A method is also known in which the height is adjusted and the contact surface is crimped, but since the surrounding area is covered with this method, it is necessary to make a viewing window 21 of heat-resistant glass, etc.
Similar to the method shown in the figure, this method has the disadvantage that inert gas is wasted.

In addition, in Figures 2 to 4, 5', 9.10 are refractories, 11 is a slider, 12 is an attachment, 1
3 is a holding metal fitting, 14 is a holder for the immersion nozzle, 18 is a cylindrical enclosure, 19 is an asbestos sheet, 23 and 24 are cylindrical enclosures, and 25° and 26 are packings.

Now, the present invention was devised to completely prevent the inflow of air with the minimum necessary gas supply amount without wasting inert gas as in the past. 7 to 7 will be explained.

The sliding nozzle 4 provided at the bottom of the tundish 3 is usually composed of two refractories 9 and 10, and the refractories 10 are slid by a hydraulic cylinder (not shown) to open and close the nozzle.

Therefore, a corrosion-resistant refractory 5' is crimped to the lower part of the refractory 10 by a presser fitting 13 via a screw of an attachment 12.

Refractory mortar is used for joints.

The slider 11 holds the refractory 10, and has screw holes etc. formed therein so that an attachment 12 can be attached thereto.

The immersion nozzle 5 has a recess that can be fitted into a lower protrusion of the refractory 5', and is held by a holder 14.

Although the holder 14 is not shown, the submerged nozzle 5 is crimped to the bottom of the refractory 5' by a suitable crimping device.

A heat-resistant gasket 27 made of asbestos or the like is provided between the upper part of the holder 14 and the presser metal fitting 13 to completely seal the gap between the holder 14 and the bottom of the presser metal fitting 13.

Further, a gasket 28 having a similar role is inserted into the lower part of the holder 14 to support the immersion nozzle.

On the other hand, a pipe 16 for introducing an inert gas 17 is also attached to the holder 14 itself, so that the inert gas 17 can be supplied to the inside of the holder 14.

The holder 14 also has a ring-shaped groove 31 and a groove 31 so that the inert gas can be supplied above the groove 31, as shown in FIG. Slit-shaped grooves 30 are provided at several locations.

Furthermore, as shown in FIG. 6, the presser fitting 13 is provided with several slit-like grooves 29 (small holes may also be used), so that inert gas can also be supplied to the joint between the refractories 10 and 5'. That's how it is.

With the above structure, the inert gas 17 is refractory 10.5'
and the joint of the immersion nozzle 5 is evenly and airtightly filled,
There is almost no leakage to the outside air, and the pressure is maintained slightly higher than atmospheric pressure.

Therefore, even if the seal at the joint is incomplete,
Contact between the molten steel flow and air can be completely prevented.

Furthermore, since there is almost no leakage of inert gas, waste of gas can be avoided, and an effective complete seal can be achieved with the minimum necessary gas supply, making it possible to produce high-quality products.

In addition, the ring-shaped grooves and slit-shaped grooves machined into the holder and presser metal fittings allow gas to be supplied evenly, and since the entire periphery is not covered, there is no need to provide a viewing window like in the past. It is relatively simple structurally.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing an outline of continuous casting equipment, and FIGS. 2 to 4 are cross-sectional views illustrating a conventional sealing mechanism of a submerged nozzle connection part. FIG. 5 is a cross-sectional view showing an embodiment of the present invention, FIG. 6 is a diagram taken along the I-■ arrow in FIG. 5, and FIG. 7 is a diagram taken along the same <n--n arrow in FIG. In the diagram; 3... Tanditshu, 5...
...Immersion nozzle, 5'...Erosion-resistant refractory, 9,1°...Refractory, 11...Slider 12...Curved attachment, 13...・・・・・・
Holder metal fitting, 14...Immersion nozzle holder, 1
6... Pipe for introducing inert gas, 17...
... Inert gas, 27 ... Patsukin, 28
...Packing, 29...Slit-shaped groove, 30...Slit-shaped groove, 31.Curve.
Ring-shaped groove.

Claims (1)

[Scope of utility model registration request] The holder itself that holds the immersion nozzle is equipped with a pipe for introducing inert gas, and the inner surface of the holder has grooves for distributing the inert gas over the entire outer circumference of the immersion nozzle,
A sealing gasket is provided between the holder and the holding metal fitting that supports the erosion-resistant refractory to which the upper part of the immersion nozzle is crimped, and between the lower part of the holder and the immersion nozzle. Sealing device for immersion nozzle connections.