JPS6145964Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a tuyere brick structure provided surrounding a gas permeable brick or pouring sprue brick in a molten metal container.

The conventional tuyere shape as shown in Figures 1 and 2 experiences thermal history such as heating up and cooling during use of the molten metal container, resulting in cracks in areas with small wall thickness, as shown in Figure 3. It is generally known that this occurs. It is well known that the service life of tuyere bricks is significantly reduced due to cracks caused by uneven wall thickness, and phenomena such as melting loss or metal spotting caused by the occurrence of cracks. This is where I am.

The present invention was developed in view of the above situation, and its feature is that in the tuyere brick structure of a molten metal container surrounded by permeable bricks or bricks for pouring molten metal, the upper tuyere brick is formed into an appropriate cross-sectional shape and a cross-sectional area smaller than the cross-section of the lower tuyere brick, and the upper and lower tuyere bricks are formed without overlapping the outer shell surface of the upper tuyere brick with the outer shell surface of the lower tuyere brick. and the outer periphery of the upper tuyere brick is filled with an expandable monolithic refractory, thereby preventing leakage of molten metal and extending the life of the tuyere brick. The mouth is located in providing a brick structure.

First, as a result of various studies conducted by the present inventors prior to the completion of the present invention, the upper tuyere bricks should be provided with an appropriate cross section, preferably a circle or a regular polygon approximating a circle, or even a short ellipse shape extremely close to a circle. , by making the wall thickness uniform or almost uniform, the cracking stress generated inside the tuyere brick is made uniform, and the crack generation factors are dispersed, and furthermore, the outer peripheral part of the upper tuyere brick is It was discovered that cracking of the tuyere bricks can be suppressed by filling the tuyere bricks with a monolithic refractory and surrounding the tuyere bricks.

Now, Fig. 1a shows a partial refractory structure at the bottom of a conventional molten metal container, such as a ladle.
indicates the upper tuyere brick formed in a square shape.

FIG. 1b is a partial cross-sectional view of the vicinity of the tuyere brick when a permeable brick is provided and FIG. 1c is a pouring sprue brick. 3 is a permeable brick, 4 is a lower tuyere brick, and 5 is a joint. 6 is a ventilation branch pipe. Furthermore, 7 is a sprue brick for pouring.

FIG. 2a is a schematic plan view showing a combination of conventional upper and lower tuyere bricks, and 8 indicates a through joint portion. In addition, Fig. 2b shows A- in Fig. 2a.
A cut plane is shown in Figure 2c, and B-B in Figure 2a is shown in Figure 2c.
Shows the cut surface.

In the conventional tuyere brick structure, as shown in Fig. 2c, a through joint 8 is formed at the overlapped part of the outer shell surface (8 in Fig. 2a) of the combination of the upper tuyere brick 2 and the lower tuyere brick 4.
I can do it. Therefore, for example, when the paving bricks 1 become worn out at the end of the operation of the ladle, the paving bricks tend to float up, causing the joints to open and molten metal to be inserted into the gaps, or to cause leakage. This in turn carries the risk of causing a major accident.

As mentioned above, the present invention is capable of sealing the joints by surrounding the outer periphery of the upper tuyere brick with an expandable amorphous refractory material such as zircon-silica, zircon-lorite, high alumina, or basic material. By preventing molten metal from being inserted between the tuyeres due to opening, and by changing the outer shell dimensions (cross-sectional area) of the upper tuyere bricks 2 and lower tuyere bricks 4, the through joints 8 are eliminated and leakage is prevented. Its feature is to prevent accidents.

FIG. 4a is a partial plan view of the bottom of the molten metal container showing the tuyere structure of the present invention, 10 shows one embodiment of the upper tuyere brick of the present invention, and 11 the upper tuyere brick surrounding the upper tuyere brick. It is a monolithic refractory that is filled and formed.

Fig. 4b is a vertical cross-sectional view of the vicinity of the tuyere showing an embodiment of the present invention in a molten metal container in which a permeable brick is provided, and Fig. 4c is a pouring sprue brick.
As shown in Figure 2, there is no joint formation.

FIG. 5a shows an example in which the outer shell dimensions of the upper tuyere brick and the lower tuyere brick are different. In particular, the upper tuyere brick 10 has a smaller cross-sectional area than the lower tuyere brick 4 and has a circular cross-section ( FIG. 4 also shows a case in which the structures are configured as shown in FIG.

Figure 5b shows the cross-section C-C in Figure 5a.
Figure c shows the DD section of Figure 5a, and it is clear that no through joint 8 has been formed.

Furthermore, by forming the cross section of the upper tuyere brick to have a circular cross section, for example, the occurrence of cracks due to thermal history such as heating and cooling can be suppressed to a small size by dispersing the cracking stress as shown in Fig. 6. I was able to do it.

By constructing and using the present invention as described above, it is possible to prevent leakage of molten metal and extend the life of tuyere bricks, and it contributes to equipment and production aspects such as maintenance management of molten metal containers and improvement of productivity. Extremely large.

[Brief explanation of the drawing]

FIG. 1a is a partial plan view showing a refractory structure at the inner bottom of a conventional molten metal container. FIGS. 1b and 1c are partial vertical cross-sectional views of the vicinity of the tuyere in a molten metal container provided with an air-permeable refractory or an injection sprue brick, respectively. FIG. 2a is a schematic plan view showing a combination of conventional upper and lower tuyere bricks. FIGS. 2b and 2c show the AA section and BB section in FIG. 2a, respectively. FIG. 3 is a diagram showing how cracks occur in conventional tuyere bricks. FIG. 4a is a partial plan view of the bottom of the molten metal showing the tuyere brick of the present invention. FIGS. 4b and 4c are longitudinal cross-sectional views of the vicinity of the tuyere, respectively, showing an embodiment of the present invention in a molten metal container provided with an air-permeable brick or an injection sprue brick. FIG. 5a shows an embodiment of the combination of the upper tuyere brick and the lower tuyere brick according to the present invention. FIGS. 5b and 5c show the AA section and the BB section in FIG. 5a. FIG. 6 is a schematic diagram of the state of crack reduction in the tuyere brick according to the present invention. 1... Paving brick, 2... Upper tuyere brick, 3... Breathable brick, 4... Lower tuyere brick, 5... Joint, 6
... Ventilation branch pipe, 7 ... Injection sprue brick, 8 ... Joint, 10 ... Upper tuyere brick, 11 ... Monolithic refractory, 12 ... Joint part, 13 ... Cracks.

Claims (1)

[Scope of utility model registration request] In a tuyere brick structure of a molten metal container that is provided surrounding a permeable brick or a brick for pouring molten metal, the upper tuyere brick is formed to have an appropriate cross-sectional shape and a smaller cross-sectional area than the cross-sectional area of the lower tuyere brick. In addition, the upper and lower tuyere bricks are formed by combining the upper and lower tuyere bricks without overlapping the outer surface of the upper tuyere brick with the outer shell surface of the lower tuyere brick, and the outer periphery of the upper tuyere brick is made of an expandable monolithic refractory. A tuyere brick structure for a molten metal container formed by filling.