JPS58116977A - Refractory structure of vessel for molten metal - Google Patents

Abstract

PURPOSE:To prolong the life of a vessel, by interposing an expansible shapeless refractory layer of which the coefft. of residual linear expansion or contraction at the ordinary sevice temp. and time of the vessel assumes a positive value between a permanent lining brick layer formed on the inside surface of a shell and the inside lining brick layer formed on the inner side thereof. CONSTITUTION:An expansible shapless refractory layer 8 is interposed between the permanent lining brick layer 2 provided on the inside surface side of a shell 1 of a vessel for molten metal and the inside lining brick layer 3 provided on the inner side thereof. Said layer 8 is formed of shapless refractories of which the rate of residual linear expansion or contraction shows a positive value at the ordinary service temp. of the vessel, that is, about 1,200-1,500 deg.C, and service time, for example, the refractories of the chemical compsn. of, by weight %, about 7.4 Al2O3, about 43.5 SiO2 and about 47 ZrO2.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a refractory structure in a molten metal container such as an Fi ladle or a tundice for a continuous casting machine.

Conventionally, when used as a molten metal container such as a ladle, for example, as shown in FIG. A structure is known in which the bricks are pasted together and a joint material 4 is filled between the inner bricks 3. In addition! @1 In the figure, numeral 5 indicates a permanently laid brick, and numeral 6 indicates a number of bricks. When the lining brick 3.6 of this cylindrical container is damaged due to use, it is common to repair the damaged part and use it again. 6
actually maintains the permanent lining bricks 2 and 5, and therefore, by repeatedly repairing the melted and damaged parts of the inner lining bricks 3.6, it is possible to substantially extend the life of the container as a whole. It is something.

However, in the conventional molten metal container configured as described above, while it is used repeatedly 9 times, gaps are formed at the joints due to thermal expansion and contraction, and from these gaps the bath molten metal 7 As shown in Figure 2, the permanent lining 9 brick 2 and the inner lining 9
The permanently attached bricks 2 may be melted and damaged by entering between the bricks 3, and as a result, there is a problem that the life of the permanently attached bricks 2 and the life of the container as a whole is shortened.

This invention was made with the aim of solving the above problem, and the residual linear expansion/contraction between the permanent brick layer and the inner brick layer is positive at the normal usage temperature and usage time of the container. It is characterized by interposing an expandable monolithic refractory material 1- that has a value.

An embodiment of the present invention will now be described with reference to FIGS. 3 and 4. In the following description, the same reference numerals as those shown in FIGS. 1 and 2 will be used in FIGS. 3 and 4 to refer to the same members as those shown in FIGS. 1 and 2. omitted.

FIG. 3 is a cross-sectional view showing an embodiment of the present invention, in which the molten metal container is located between a permanent lining brick 2 provided on the inner surface of the steel shell 1 and an inner lining brick 3 provided on the inner surface thereof. In this structure, an expandable monolithic refractory layer 8 is interposed. Here, the term "expandable monolithic refractory" refers to the normal operating temperature of the container (12
It refers to a monolithic refractory whose residual linear expansion/contraction coefficient exhibits a positive value over a period of 00°C to 1500°C) and usage time. For example, when a container is kept at a temperature of about 1300°C for about 3 hours, It has the chemical composition and residual linear expansion/contraction ratio shown in Table 1.

Table 1 Also, the reason why the deficient refractory interposed between the permanent brick 2 and the inner brick 3 is made of the expandable material described above is as follows. In other words, the monolithic refractory No. 8 is heated and expands when molten metal is placed in the container, and if #di is still empty, it naturally shrinks and shrinks, so the monolithic refractory No. 8 There is a risk that cracks will inevitably occur and the cracks will cause the bath molten metal to enter the permanently bonded brick 2. Therefore, during use, the cracks are sealed by thermal expansion and maintained in that state. At the same time, the monolithic refractory expands thermally and forms a dense layer on the lining brick 3, and as a result, the opening of the monolithic refractory layer 8 in the gap created at the joint is closed 1ffj by the monolithic refractory. This is to maintain that state during toilet use.

Note that the refractory forming the amorphous refractory layer 8 has a residual-expansion/contraction ratio that is a positive value as described above, and at the same time, the amount of expansion does not change even if the expansion and contraction are repeated many times. It is preferable that the material has a change in diameter.

However, if the refractory provided on the inner surface of the steel shell 1 is configured as shown in the upper d pi, and if there is a gap at the joint between the lining bricks 3, then Also, since the open end of the monolithic refractory layer 8 in the gap is sealed by the monolithic refractory layer 8 which has thermally expanded during use, molten metal flows between the lining bricks 3 and the monolithic refractory layer 8. There is little risk of the metal entering between the lining brick 3 and the monolithic refractory layer 8, as shown in FIG. Since the layer 8 is made of thermally expandable wood as described above, any cracks that occur in the layer 8 will be sealed during use, and therefore there will be no cracks between the lining brick 3 and the monolithic refractory layer 8. The molten metal 7 that has entered is prevented from further entering by the amorphous refractory layer 8, and does not reach the permanently sticky bricks 2. In this way, in the above-mentioned molten metal container, even if the molten metal J1g7 invades the refractory layer formed on the inner surface of the iron shell 1, it will not reach the maximum extent between the lining bricks 3 and the monolithic refractory layer 8. Therefore, the molten gold NI47 will not reach the permanently attached bricks 2, and therefore there is no risk of the permanently attached bricks 2 being melted and damaged, so it is possible to improve the life of the permanently attached bricks 2 and, by extension, the life of the container itself. can.

In addition, since the monolithic refractory layer 8 performs its inherent function of preventing the intrusion of molten metal by thermal expansion, before pouring #r molten metal into the container, the container, especially the monolithic refractory layer 8, is It is preferable to preheat the side Iis provided with 8 to a predetermined temperature.

Further, in the above embodiment, the composition shown in Table 1 was used as the refractory material forming the amorphous refractory layer 8, but the present invention is not limited to the above embodiment, and the composition shown in Table 1 is not limited to the above embodiment. The monolithic refractory layer 8 may be formed of a refractory other than the refractory described above, in short, the monolithic refractory layer 8 may be formed of a thermally expandable refractory.

Furthermore, in the example of Jokisou, an example was explained in which the expansible amorphous refractory layer 8 was provided only on the wall of the container. A refractory layer may also be provided.

As is clear from the above explanation, according to the refractory structure of the molten metal container of the present invention, the expandable monolithic refractory 1- interposed between the permanent brick and the inner brick is used. Since it is possible to prevent molten metal from penetrating into the permanently attached bricks and to prevent the permanently attached bricks from being melted and damaged, it is possible to improve the life of the permanent bricks and the life of the container itself.
In addition, since the permanently attached bricks will not be damaged by melting, it is possible to reduce the refractories and costs required for repairing them, and it is also effective in preventing dangers such as hot water leakage due to wear and tear of the permanently attached bricks and iron skin. .

[Brief explanation of the drawing]

Fig. 1 is a small cross-sectional view of an example of a conventional molten metal container, Fig. 2 is a partially enlarged view of the part ■ in Fig. 1, and Fig. 23 is a sectional view showing an embodiment of the present invention. FIG. 1 is a partially enlarged view of the ■ part. 1... Iron shell, 2... Permanently bonded brick, 3... Inner layer brick 1c, 8... Expandable monolithic refractory layer. Applicant Kawasaki Steel Corporation Figure 1 Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] Made by pasting refractories on the inner surface of the iron skin that makes up the exterior structure.
In the financial container, there is a layer between the permanent brick layer formed on the inner surface of the steel shell and the inner brick layer formed on the inward side of the permanent brick layer at the normal operating temperature of the container. and residual linear expansion contraction over usage time! A refractory structure for a molten metal container in which an expandable monolithic refractory layer, one of which has a positive value, is interposed.