JPH0734119A - Immersion pipe for vacuum degassing device - Google Patents

Abstract

PURPOSE:To improve the durable life of the immersion pipe for a vacuum degassing device. CONSTITUTION:This immersion pipe 1 for the vacuum degassing device has an inner regular shaped brick 5 on the inner side of an iron core 2 having a cylindrical shape and is packed with amorphous refractories 11 between the iron core 2 and the inner regular shaped brick 5. A molten metal flow passage 4 is formed within the inner regular shaped brick 5. The immersion pipe has an outer regular shaped brick 9 between a supporting part 6 for the bottom end of the outer regular shaped brick and supporting part 7 for the top end of the outer regular shaped brick disposed at the iron core 2 on the outer side of the iron core 2. The amorphous refractories 12 are packed between the iron core 2 and the outer regular shaped brick 8. The immersion pipe has the amorphous refractories 15 on the lower side of the inner regular shaped brick 5 and the outer shaped brick 8 as well.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dip tube for a vacuum degassing apparatus, which is used as a dipping tube for a vacuum degassing apparatus and is suitable for extending the service life.

[0002]

2. Description of the Related Art In recent years, the mass production of steel has been upgraded, and various special refining methods such as vacuum refining and alternative refining outside the furnace have been adopted.

Vacuum refining includes suction vacuum refining methods such as the DH method and the RH method, and such special refining methods are also widely adopted.

In the DH method and the RH method, a vacuum degassing apparatus having a dip tube at the lower end of a vacuum tank is used, and the molten steel is sucked into the vacuum tank through the dip tube and brought into contact with vacuum to degas the molten steel. I am trying.

FIG. 5 shows an example of a conventional structure of a dip tube for a vacuum degassing apparatus. The dip tube 51 has an inner fixed brick that protrudes inward in a lower portion of a cylindrical iron core 52. A lower end support portion 53 is provided, and the inner fixed brick bottom end portion 53 supports an inner fixed brick 55 that forms a molten steel flow path 54 therein, and is provided outside the cylindrical iron core 52. , A plurality of anchors 56 are provided from the upper side to the lower side of the iron core 52.
The irregular refractory 57 is filled between the inner and inner fixed bricks 55, the irregular refractory 58 is provided outside the iron core 52, and the irregular refractory 59 is provided below the iron core 52. It has a structure.

When vacuum degassing is performed, the immersion pipe 51 is immersed in the molten steel 60, and the molten steel 60 is sucked up into the vacuum chamber through the inside of the immersion pipe 51 (in this way, outside). For the structure of the dip tube using the amorphous refractory, see, for example, "3rd Edition Iron and Steel Handbook II, Ironmaking and Steelmaking", Iron and Steel Institute of Japan, 1979.
Page 676, published October 15, 2015
13) and FIGS. 13 and 18 (RH device) show a structure in which high alumina castable is used as an amorphous refractory. ).

[0007]

However, in such a conventional immersion pipe 51 for a vacuum degassing apparatus, the outer portion of the immersion pipe 51 which comes into contact with the molten steel 60, particularly the molten steel 6 is used.
Since the outer portion of the dip pipe 51 that contacts the surface of 0 was formed by the irregular refractory 58, erosion is likely to be large, the number of times of service is short, the life is short, and the number of times of repair is required. There was a problem, and it was an issue to extend the service life.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and it is possible to extend the service life and extend the life of a dipping tube for a vacuum degassing apparatus. The purpose is to

[0009]

An immersion pipe for a vacuum degassing apparatus according to the present invention has an inner fixed brick provided inside a cylindrical iron core, and a molten steel passage is formed inside the inner fixed brick. In addition, it is characterized in that the outer fixed brick is provided on the outer side of the iron core.

In an embodiment of the immersion pipe for a vacuum degassing apparatus according to the present invention, a lower end of a cylindrical iron core is provided with a lower end support portion of an inner shaped brick projecting inward and an outward direction upward. The outer fixed brick protruding in the inclined state may have a lower end support portion, and the upper portion of the iron core may have an outer fixed brick upper end support portion protruding in the downward inclined state. ,
In addition, a void may be provided between the iron core having a cylindrical shape and the outer fixed brick, and the void may be filled with an amorphous refractory.

[0011]

The immersion pipe for a vacuum degassing apparatus according to the present invention has an inner fixed brick having a molten steel flow passage formed inside a cylindrical iron core. In addition to good erosion resistance, the outer core of the iron core also has an outer fixed brick, so it has good erosion resistance to molten steel placed in a ladle, etc. and slag components on the surface of molten steel. The increase in the life reduces the number of repairs, which is advantageous in terms of material cost and operating cost.

[0012]

1 to 4 show an embodiment of a dipping tube for a vacuum degassing apparatus according to the present invention, wherein the dipping tube 1 is provided below a cylindrical iron core 2. The inner fixed brick protruding inward is provided with the lower end support portion 3,
The inner fixed brick lower end supporting portion 3 supports the inner fixed brick 5 that forms the molten steel flow path 4 inside, and is provided in a lower portion of the iron core 2 having the cylindrical shape in a state of being inclined upward in the outward direction. Outer fixed brick lower end support 6
In addition, an outer fixed brick upper end supporting portion 7 protruding downward in an outwardly inclined state is provided on an upper portion of the iron core 2 having a cylindrical shape, and a lower end of the inclined outer fixed brick provided to the iron core 2 is supported. The outer fixed brick 8 is provided between the upper fixed portion 7 and the outer fixed brick which is inclined similarly to the portion 6.
An amorphous refractory 1 is formed by pouring a fluid amorphous refractory into the gap between the iron core 2 and the inner fixed brick 5 from above.
As shown in FIG. 4, in the void portion between the iron core 2 and the outer fixed refractory 8, the outer fixed brick is flowed from the irregular shaped refractory flow inlet 7a formed in the upper end supporting portion 7 as shown in FIG. The irregular refractory is poured and filled as the irregular refractory 12, and the irregular refractory 14 is also filled between the flange 13 provided on the upper end of the iron core 2 and the outer fixed brick upper end support 7, and the inner side. An irregular refractory material 15 is provided below the fixed brick 5 and the outer fixed brick 8, and the irregular refractory material 15 is held by a plurality of irregularly shaped anchors 16 provided at the lower end portion of the iron core 2. The outer circumference of the belt 17
It has a structure wound with.

Therefore, in the immersion pipe 1 for a vacuum degassing apparatus according to this embodiment, an inner portion forming the molten steel flow path 4,
Since both of the outer parts that come into contact with the molten steel surface in the ladle and the like are formed by the fixed bricks 5 and 8, the erosion resistance is improved compared to the case of using an irregular refractory, and the irregular shape is improved. If it is made of refractory material, the service life is about 50
In contrast to the case of regular bricks, the service life was increased to about 80 times when the regular bricks were formed, and the service life could be extended and the repair man-hours could be reduced.

[0014]

As described above, according to the immersion pipe for a vacuum degassing apparatus of the present invention, the inner fixed brick is provided inside the iron core having a cylindrical shape, and the molten steel is provided inside the inner fixed brick. While forming the flow path, because it has a configuration in which the outside fixed brick is provided on the outside of the iron core,
The erosion resistance of the dipping pipe is improved, the number of times of service can be increased, and the remarkably excellent effect that the service life can be extended and the number of repair processes can be reduced is brought about.

[Brief description of drawings]

FIG. 1 is an explanatory longitudinal sectional view of a dip tube for a vacuum degassing apparatus according to an embodiment of the present invention.

FIG. 2 is an explanatory view seen from a direction II in FIG.

FIG. 3 is an explanatory view seen from a direction III in FIG. 1.

FIG. 4 is an explanatory diagram viewed from the IV direction in FIG.

FIG. 5 is a vertical cross-sectional explanatory view of a conventional dip tube for a vacuum degassing apparatus.

[Explanation of symbols]

 1 Vacuum Degassing Equipment Immersion Tube 2 Cylindrical Iron Core 3 Inner Brick Lower End Support 4 Molten Steel Flow Path 5 Inner Brick 6 Outer Brick Lower Support 7 Outer Brick Upper Support 8 Outer Brick 11 No Standard refractories 12 Irregular refractories 14 Irregular refractories 15 Irregular refractories 16 Deformed anchors 17 Band iron

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kuniyoshi Torii 2-10-106 Harayamadai, Seto City, Aichi Prefecture (72) Inventor Eiji Kawamoto 19-1 Asamerai, Seto City, Aichi Prefecture Rainbow Shin Seto 503

Claims (3)

[Claims] 1. A cylindrical iron core is provided with an inner fixed brick inside, a molten steel flow path is formed inside the inner fixed brick, and an outer fixed brick is provided outside the iron core. An immersion tube for a vacuum degassing device, which is characterized in that 2. The lower end of a cylindrical iron core is provided with a lower end support portion of an inner fixed brick that projects inward, and an outer fixed brick bottom end portion that is projected outward in an upwardly inclined state, The dip tube for a vacuum degassing device according to claim 1, wherein an outer fixed brick upper end support portion protruding outward in a downwardly inclined state is provided on an upper portion of the iron core. 3. The immersion pipe for a vacuum degassing apparatus according to claim 1, wherein there is a void between a cylindrical iron core and an outer regular brick, and the void is filled with an irregular refractory material.