JPH032355Y2 - - Google Patents

Description

[Detailed description of the invention] <Industrial application> This invention prevents cooling air and water from coming into direct contact with the lower part of the mold, prevents breakout due to boiling of the hot water surface, and reduces mold erosion. This invention relates to continuous casting molds.

<Prior art and its problems> In continuous casting operations, slabs pulled from a mold are held by a number of rolls arranged at appropriate intervals and transferred to the next process, but there is no chance that the slabs will pass through the mold. The area is cooled by cooling air and water mixed with gas such as air that is ejected from the nozzle. Part of the cooling air and water injected from this cooling air and water nozzle instantly vaporizes and becomes water vapor, and part of it becomes water droplets wrapped in the water vapor and scatters at high speed. Erodes the lower part.

As a technique for preventing erosion of the lower part of the mold, there is a continuous casting mold in which a protective metal coating layer is provided on the lower end surface of the mold base and the lower surface of the cooling box, as shown in Japanese Patent Application Laid-Open No. 57-19130. . According to this type of mold, the lower end surface of the mold base has corrosion resistance, and as a result, the life of the mold can be extended, but it has been found that other problems as described below remain unsolved.

In other words, since the above-mentioned cooling air/water nozzle is usually installed so that the cooling air/water is applied to the slab with a certain spread, some of the cooling air/water may flow upwards into the mold. be.

Furthermore, the cooling air/water nozzle may become eccentric or deformed during roll disassembly or assembly, or may be deformed due to radiant heat from the hot slab, resulting in a change in the initial installation condition and the tip opening of the cooling air/water nozzle. Occasionally, a situation may occur where the part is directed upwards more than necessary.

Cooling air and water flowing upward into the mold due to such causes enters the air gap between the mold inner wall surface and the slab, and in some cases rises to the surface of the molten metal, causing boiling and the risk of breakout. Another problem is that the lower part of the mold is eroded excessively due to the water vapor jetting to the upper part.

By the way, there is a technique disclosed in Japanese Unexamined Patent Application Publication No. 60-6258 to prevent the boiling phenomenon caused by water vapor. This is on the bottom of the mold.
The purpose is to straighten the upper surface of the air water injected from the air water nozzle horizontally or downwardly, and for this purpose, a configuration is shown in which an upper surface correction plate for the air and water flow is connected to the mold with bolts. In such a configuration, the bolts were easily damaged by high heat, sometimes leading to the bolts falling off, and the straightening plate between the bolts was significantly deformed and no longer functioned as a straightening plate, which caused further problems in terms of practicality. .

The present invention aims to solve the above-mentioned problems and provide a mold for continuous casting that is highly practical.

<Means for solving the problem> In order to achieve the above purpose, the inventors of the present invention have developed a system in which cooling air and water are placed in the lower end surface of the mold body, integrally with the mold body, in the upward direction. This continuous casting mold is characterized in that it has a protruding blocking plate that blocks the jet stream, and the blocking plate has an inner surface of the mold located outward from the inner surface of the mold body.

In addition, in the continuous casting mold of the present invention, the mold body is made of copper or copper alloy, as is commonly used, and the inner surface is coated with various conventionally known materials such as nickel or its alloy as a wear-resistant protective layer. Of course, a protective layer and a chromium layer may be provided on the upper surface of the protective layer as necessary, and such a protective layer may also be provided on the lower end surface of the mold body.

In addition, the shielding plate in the present invention is molded as an integral part with the mold body, and is made of copper or copper alloy like the mold body described above, and has various corrosion-resistant coating layers such as nickel on its surface. Sometimes it is worn.

<Embodiments and operations> The present invention will be described in detail below with reference to drawings showing embodiments.

What is shown in FIG. 1 is the continuous casting mold of the present invention, in which a blocking plate 2 is provided on the lower end surface of the mold body 1.
is integrally formed with. In the figure, numeral 3 indicates a back frame, 4 a cooling water slit formed on the back surface of the mold body, 5 a cooling air/water nozzle, and 6 a slab support roll. Also, in FIG. 2, the blocking plate 2 and the mold body 1 are the same in that they are integral, but the blocking plate 2 is constructed by sequentially protruding the lower part of the mold body in a curved manner outward.
An example is shown below.

As shown in FIGS. 1 and 2, in the continuous casting mold of the present invention, a blocking plate 2 is formed in a protruding manner on the lower end surface of the mold body 1.
The cooling air and water injected from the cooling air and water nozzle 5 is naturally affected by various factors such as those mentioned above, as well as when the cooling air and water nozzle 5 is installed at a normal angle. Therefore, even if the nozzle opening faces upward due to deformation or angle deviation, the cooling air and water sprayed upward from the cooling air and water nozzle 5 will not directly hit the slab. , hits the slab once in the form of hitting the shielding plate 2 and being reflected from there. Therefore, the back side of the shielding plate 2, that is, the surface facing the cooling air/water nozzle 5, has an inclined surface as shown in FIGS. 1 and 2, so that the cooling air/water injected from the cooling air/water nozzle 5 It is desirable to have a configuration in which when reflected, the light is directed diagonally inward and downward.

In addition, in the continuous casting mold of the present invention, the inner surface of the mold is not flush with the inner surface of the mold body 1, but is retracted outward, so that during operation. A space is formed between the mold inner surface of the shielding plate 2 and the slab, and the rising air in the cooling air water that hits the slab escapes into this space, and the mold body 1 The amount of air and water that rises through the air gap between the cast slab and the cast slab becomes almost nothing.

<Effects of the invention> As described above, according to the continuous casting mold of the present invention, the continuous casting mold of the present invention has the following effects:
Since the shielding plate is integrated with the mold body, cooling air and water will not directly hit the lower surface of the mold body, and the space formed between the mold inner surface of the shielding plate and the slab will be reduced. Since it acts as an escape for rising air water, it is possible to prevent breakout due to boiling of the hot water surface due to the upper jet of steam, and it is also possible to reduce erosion caused by steam near the bottom surface of the mold. Since this blocking plate is integrated with the mold body, there are no defects such as wear and falling of mounting bolts or deformation of only the blocking plate, as in the device shown in the above-mentioned Japanese Patent Application Laid-Open No. 60-6258. Since the shielding plate is positioned further outward than the inner wall surface of the mold, that is, the inner surface of the shielding plate is positioned toward the outside of the mold, the shielding plate does not come into direct contact with the slab, so there is no chance of the shielding plate being worn out. It has various effects such as:

[Brief explanation of drawings]

FIG. 1 is an explanatory view showing one embodiment of the continuous casting mold of the present invention, and FIG. 2 is an enlarged explanatory view of essential parts showing another embodiment. In the figure, 1: mold body, 2: blocking plate, 3: back frame, 4: cooling water slit, 5: cooling air/water nozzle, 6: slab support roll.

Claims (1)

[Scope of utility model registration request] On the lower end surface of the mold body, integrally with the mold body,
For continuous casting, characterized in that a blocking plate is protruded to block an upward jet of cooling air water, and the blocking plate has an inner surface of the mold located outward from the inner surface of the mold body. template.