JP2727937B2 - Cast-in method of Steve cooler for cooling blast furnace body - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for casting a Steve cooler used for cooling a furnace wall or the like of a blast furnace.

[0002]

2. Description of the Related Art When casting refractory bricks integrally into a Steve cooler used to cool the furnace walls of a blast furnace,
There is a problem that cracks occur in refractory bricks. Conventionally, as a means for preventing such cracking of the refractory brick, a heat insulating cushioning material such as rock wool is attached to both sides of the refractory brick and then cast-in. However, in the above-described method, rock wool used as a cushioning material is expensive, and there is a problem in the thermal conductivity of the refractory brick, and a gap is generated between the refractory brick and the rock wool, and the refractory There were problems such as the brick falling out.

As means for solving the above-mentioned problem, Japanese Patent Application Laid-Open No. 63-192805 discloses a method in which a refractory brick in contact with a casting to be cast is covered with metal wool and then cast. Japanese Patent Application Laid-Open No. 63-192806 discloses a method (hereinafter referred to as prior art) in which a refractory brick having a surface in contact with the casting is covered with a metal plate and then cast.

FIG. 4 is a bottom view of a Steve cooler, and FIG. 5 is a sectional view taken along line AA of FIG. 4, which shows the prior art. As shown in FIGS. 4 and 5, a plurality of refractory bricks 1 arranged in a row are arranged in parallel at predetermined intervals, and metal wool (or metal Plate material) 2 is attached. Reference numeral 3 denotes asbestos inserted between each of the plurality of refractory bricks 1 and 4
Is a cast cooler main body.

[0005]

The prior art described above has the following problems. That is, metal wool or the like affixed to the refractory brick becomes a hindrance factor for efficiently transmitting the temperature distribution, and the work efficiency is poor. Furthermore, at the time of casting, as a result of the thickness of the metal wool or the like being less than half of the initial value, the refractory brick is dropped due to the generated gap, or the heating surface is increased due to the flow of hot gas into the generated gap. This causes thermal spalling, which tends to cause cracks and cracks in the refractory brick. In order to prevent the above-mentioned gap from being generated, the heat insulating cushioning material and the metal wool are separately used, but in such a conventional method, heat insulation for the refractory brick is sufficiently performed. Hard to say.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-mentioned conventional problems, and to cast a refractory brick integrally into a Steve cooler used for cooling a furnace wall of a blast furnace. On the other hand, it is intended to provide a method for casting a steal cooler for cooling a blast furnace furnace body, in which the molten metal does not directly attack, the thermal stress inside the refractory brick is suppressed, and the refractory brick does not crack or crack. is there.

[0007]

According to the present invention, there is provided a method for integrally casting bricks in a Steve cooler for cooling a blast furnace furnace body, the method comprising: providing a siliceous material between the surface of the refractory brick and the surface of the Steve cooler body. The present invention is characterized in that a material for preventing intrusion of molten metal and a heat insulating material are interposed and then cast.

[0008]

In the method of the present invention, as described above,
Between the surface of the refractory brick and the surface of the Steve cooler body, a siliceous molten metal intrusion prevention material and a heat insulating material are interposed. Therefore, the refractory brick is excellent in heat transfer coefficient and has a good heat insulating effect, and no cracks or cracks are generated in the refractory brick, so that the refractory brick can be cast without damage.

[0009]

Next, the method of the present invention will be described with reference to the drawings. FIG. 1 is a sectional view taken along the line BB of the stee cooler in FIG. 4, showing one embodiment of the method of the present invention. As shown in the drawing, the surface of the cast steel cooler main body 4 facing the refractory brick 1 and the surface of the plurality of SiC-based refractory bricks 1 arranged in parallel at predetermined intervals facing the stee cooler main body 4. Between them, a siliceous molten metal intrusion prevention material 5 and a heat insulating material 6 are interposed.

The siliceous metal intrusion prevention material 5 is a fibrous sheet made of amorphous silica and having a diameter of 8 to 10 μm. An example of the chemical composition is shown in Table 1 below.
And its thermal conductivity is shown in FIG.

[0011]

[Table 1]
(wt.%)

Since such a material 5 for preventing intrusion of molten metal does not contain a binder, the binder is gasified by heat during the casting operation, so that a defect occurs in the cast product or a problem occurs in work safety. There is nothing.

The heat insulating material 6 is made by integrating a glass fiber and a ceramic fiber by a needle punching method. An example of the chemical component composition is shown in Table 2 below.

[0014]

[Table 2] (wt.%)

Incidentally, the thermal conductivity (λ) of the heat insulating material 6 is expressed as λ (Kcal / mh ° C.) = 0.0279 + 0.000123 θ as an average temperature θ (° K). (At 70 ° C, about 0.0033 Kcal / mh ° C)

According to the method of the present invention, a case where a siliceous molten metal intrusion preventing material and a heat insulating material are interposed between a refractory brick and a Steve cooler main body and a case where a molten metal intrusion preventing material and a heat insulating material are not interposed. With the conventional method cast in
The temperature transmission state of the SiC-based refractory brick was examined, and the results are shown in FIG.

In FIG. 3, the solid line A indicates the temperature of 20 mm from the brick surface according to the method of the present invention, the dotted line A 'indicates the temperature of 20 mm from the brick surface according to the conventional method, and the solid line B indicates the temperature of 50 mm from the brick surface according to the method of the present invention. The dotted line B 'indicates a temperature of 50 mm from the brick surface according to the conventional method, the solid line C indicates a temperature of 150 mm from the brick surface according to the present invention, and the dotted line C' indicates a temperature of 150 mm from the brick surface according to the conventional method. And
Solid line D indicates the temperature of 300 mm from the brick surface according to the method of the present invention, and dotted line D 'indicates the temperature of 300 mm from the brick surface according to the conventional method.

It is apparent from FIG. 3 that the method of the present invention provides an excellent heat insulating effect. In addition, when the temperature difference inside the refractory brick is large, the thermal stress is also large, and the occurrence of cracks and cracks is induced.However, when the heat insulation measures such as the present invention are taken, the absolute temperature is also low. Therefore, the temperature difference can be suppressed, and the refractory brick can be cast-in without being damaged.

[0019]

As described above, according to the present invention,
When casting refractory bricks integrally into a Steve cooler used to cool the furnace walls of the blast furnace, the molten metal does not attack the refractory bricks directly, suppressing the thermal stress inside the refractory bricks Thus, cracks and cracks do not occur in the refractory brick, and an industrially useful effect is brought about.

[Brief description of the drawings]

FIG. 1 is a sectional view of a steve cooler illustrating the method of the present invention.

FIG. 2 is a graph showing the thermal conductivity of the molten metal intrusion prevention material used in the present invention.

FIG. 3 is a graph showing a comparison of a state of temperature transmission of a refractory brick between a case where the brick is cast by the method of the present invention and a case where it is cast by a conventional method.

FIG. 4 is a bottom view of a Steve cooler.

FIG. 5 is a sectional view taken along line AA of FIG. 4 and shows the prior art.

[Explanation of symbols]

 1 Refractory brick, 2 Metal wool, 3 Asbestos, 4 Cast cooler body, 5 Infiltration prevention material, 6 Insulation material.

Claims (1)

(57) [Claims] 1. A method for integrally casting a refractory brick into a Steve cooler for cooling a blast furnace furnace body, the method comprising: A cast-in method for a Steve cooler for cooling a blast furnace body, comprising interposing a material and casting.