KR100194332B1 - Magnesia carbonaceous lead for electric furnace exit - Google Patents

Abstract

The present invention relates to an electric furnace magnesia-carbon bearing support, and after determining the appropriate particle size of the raw material to be blended and training, select the appropriate amount of silicon carbide added during the compounding through the first pilot test, step by step The second and third tests are carried out to select the blending amount of the raw material having the most suitable physical properties, but the particle size of 5-3㎜ electrolytic magnesia clinker is 9-11wt%, the particle size of 3-1㎜ electrolytic magnesia clinker 1 class 9- 11wt%, 14-16wt% molten magnesia clinker of 1mm or less in particle size, 4-6wt% of fine molten magnesia clinker, 2-1 9-11wt% of molten magnesia clinker in particle size, 3 grain size -1㎜ 2 molten magnesia clinkers 9-11wt%, particle size 1mm or less 2 molten magnesia clinkers 2-6 4%, particle size 3-1mm purity 98% 9-11wt% sintered magnesia clinker, fine purity 98 % Sintered magnesia clinker 9-11wt%, purity up 99% 100 wt% of a raw material composed of 6-8 wt% of lead, 98% purity of 7-9 wt% of graphite, an antioxidant of 1-3 wt% of aluminum, 1-3 wt% of magnesium / aluminum alloy, and 4-6 wt% of silicon carbide, Consisting of 3-6wt% of phenolic resins, appropriate amount of silicon oxide (SiC), a complex antioxidant, can be used to improve the oxidation resistance and hot strength while maintaining the corrosion resistance as it is based on the current products used as the supporting lead. It is effective to realize variety of varieties according to the change of raw materials and additives.

Description

Magnesia carbonaceous lead for electric furnace exit

The present invention relates to a magnesia-carbon bearing bed, and more particularly, to a magnesia-carbon bearing bed for electric furnace tap with increased oxidation resistance and hot strength.

Recently, in order to improve the quality and productivity of high quality steel in electric furnace, the development of electric bottom tapping (ETB) electric furnace with large capacity eccentricity has been actively progressed, and the methane used for the exit of ETB electric furnace is magnesia. -As the carbon material, it is directly in contact with the atmosphere, and the hot strength due to the excessive attachment of carbon due to the oxidation of carbon at the extreme end of the supporting lead and the molten steel scattering due to the enlargement of the diameter of the extreme is reduced. Along with the problem of safety accidents due to molten steel splashing, spalling occurs at the extremes of the supporting lead and abnormal erosion occurs at the top of the supporting lead.

Accordingly, the present invention has been made to solve the above problems, silicon carbide which is a complex antioxidant to improve the oxidation resistance and hot strength while maintaining the corrosion resistance as it is based on the current product used as a supporting lead ( It is an object of the present invention to provide a magnesia-carbon bearing base for electric furnace tap that enables to add a proper amount of SiC and to realize variety of varieties according to changes of raw materials and subsidiary materials.

The present invention for achieving the above object is to determine the appropriate particle size of the raw material to be blended and trained, then select the appropriate amount of silicon carbide added during the compounding through the first pilot test, step by step, the second, third pilot Select the blending amount of the raw material that shows the most suitable physical properties by performing the test, but the particle size of 5-3㎜ electrolytic magnesia clinker 9 kinds 9-11wt%, particle size 3-1㎜ electrolytic magnesia clinker 1 species 9-11wt%, particle size 1 Melt magnesia clinker of 14 mm or less, 14-16 wt%, granulated magnesia clinker, 4-6 wt% of fine granulated magnesia, particle size 3-1 mm 2 9-11 wt% of molten magnesia clinker, 3-1 mm of molten magnesia Clinker 2 types 9-11wt%, particle size 1mm or less Electrolytic magnesia Clinker 2 types 4-6wt%, particle size 3-1mm Purity 98% Sintered magnesia Clinker 9-11wt%, Fine purity 98% Sintered magnesia clinker 9-11wt%, Purity 99% Graphite 6-8wt%, Purity 98w t% 100% by weight raw material consisting of 7-9% by weight graphite, an antioxidant consisting of 1-3% by weight of aluminum, 1-3% by weight of magnesium / aluminum alloy, 4-6% by weight of silicon carbide, and 3-6% by weight of phenolic resin It is characterized by consisting of a binder consisting of.

In addition, as another embodiment of the present invention, a molten magnesia clinker having a particle size of 5-3 mm, 9-11 wt%, and a molten magnesia clinker having a particle size of 3-1 mm, 9-11 wt%, a particle size of 1 mm or less 1 type 9-11wt%, fine molten magnesia clinker 1 type 4-6wt%, particle size 3-1㎜ 2 type molten magnesia clinker 9-11wt%, particle size 3-1mm 2 type magnesia clinker 9-11wt %, Particle size less than 1mm Electrolytic magnesia clinker 2 kinds 4-6wt%, particle size 3-1㎜ Purity 98% Sintered magnesia clinker 9-11wt%, Fineness of 99t% Fine sintered magnesia clinker 9-11wt%, Purity 98 % 100wt% of raw material composed of 14-16wt% graphite graphite, antioxidant 1-3wt% of aluminum, 1-3wt% of magnesium / aluminum alloy, 4-5wt% of silicon carbide, and 3-6wt% of phenolic resin It is characterized by consisting of a binder made up.

1 is a comparative diagram illustrating the effect on the oxidation resistance and corrosion resistance according to the addition of silicon carbide in the first test.

2 is a comparative diagram illustrating the effect on the hot bending strength according to the addition of silicon carbide in the first test.

3 is a comparative diagram illustrating the effect on the oxidation resistance and corrosion resistance according to the addition of silicon carbide in the second test.

4 is a comparative diagram illustrating the effect on the hot bending strength according to the addition of silicon carbide in the second test.

5 is a comparative diagram illustrating the effect on the oxidation resistance and corrosion resistance according to the change of raw materials in the third test.

6 is a comparison diagram illustrating the change in the coefficient of hot line expansion according to the change of raw materials in the third test.

Hereinafter, preferred embodiments of the present invention will be described in detail.

Table 1 below shows the composition ratios of the raw materials and subsidiary materials applied to the current product M and the compositional ratios of the raw materials and subsidiary materials applied to the first to third pilot tests, respectively.

At this time, the third pilot test is a series of kneading process, forming, drying, and the final formulation is improved and adjusted by step by step through the first and second pilot test proceeds to a predetermined process Example 1 to Example 4 Each specimen was prepared by multiplying the specimen, and the physical properties of each specimen were compared with the comparative example of the current article.

Hereinafter, specific examples and comparative examples of the present invention will be described.

Example 1

Particle size 5-3mm electrolytic magnesia clinker, 1 type 10wt%, particle size 3-1mm electrolytic magnesia clinker, 1 type 10wt%, electrolysis magnesia clinker of 1mm or less 1mm 15wt%, granule magnesia clinker 1 type 5wt%, particle size 3-1㎜ Electrolytic magnesia clinker 2 kinds 10wt%, particle size 3-1㎜ electrolysis magnesia clinker 2 species 10wt%, particle size 1mm or less 2 molten magnesia clinker 2 species 5wt%, particle size 3-1㎜ purity 98% sintered magnesia clinker 10wt%, fine purity 98% sintered magnesia clinker 10wt%, purity 99% impression graphite 7wt%, purity 98wt% purity graphite 8wt%, 2wt% aluminum, magnesium Magnesia-carbon support base for electric furnace tap, characterized in that consisting of an antioxidant consisting of 2wt% aluminum alloy, 5wt% silicon carbide, and a binder consisting of 4.5wt% phenolic resins.

Example 2

Magnesia-carbon paper base lead for electric furnace exit characterized in that 10wt% of one kind of electrolytic magnesia clinker having a particle size of 1 mm or less is added in the composition ratio of the same raw material and subsidiary material as in Example 1.

Example 3

In the composition ratio of the same raw material and secondary raw material as in Example 2, the 99% purity 99% graphite phosphate without adding 99% purity graphite phosphate 15% by weight of the magnesia-carbon support base for electric furnace tap .

Example 4

Particle size 5-3mm Electrolytic magnesia clinker 20 %% 1, Particle size 3-1mm Magnesia clinker 30 %% 1, Magnesia clinker 20% 1% or less 1mm in particle size, Fine magnesia clinker 1 type 100 wt% of raw material consisting of 10 wt%, 99% purity 99% by weight graphite, 2 wt% of aluminum, 2 wt% of magnesium / aluminum alloy, 5 wt% of silicon carbide, and binder of 4.5 wt% of phenolic resin Magnesia-carbon support base for electric furnace door characterized in that it is.

[Comparative Example]

Particle size 5-3mm electrolytic magnesia clinker, 1 type 10wt%, particle size 3-1mm electrolytic magnesia clinker, 1 type 10wt%, electrolysis magnesia clinker of 1mm or less 1mm 15wt%, granule magnesia clinker 1 type 5wt%, particle size 3-1㎜ Electrolytic magnesia clinker 2 kinds 10wt%, particle size 3-1㎜ electrolysis magnesia clinker 2 species 10wt%, particle size 1mm or less 2 molten magnesia clinker 2 species 5wt%, particle size 3-1㎜ purity 98% sintered magnesia clinker 10tw%, fine purity 98% sintered magnesia clinker 10wt%, purity 99% purity graphite 7wt% 100% purity, 98% purity graphite 8wt%, aluminum 2wt%, magnesium Magnesia-carbon support base for electric furnace tap, characterized in that consisting of an antioxidant consisting of 2wt% aluminum alloy, 5wt% silicon carbide, and a binder consisting of 4.5wt% phenolic resins.

At this time, the physical property test of the comparative example of the current product is shown in the results of the first test to the third test, respectively, M1, M2, M3.

FIG. 1 and FIG. 2 show the first tests for selecting the appropriate amount of silicon carbide, and FIG. 1 shows the same amount of each of the raw materials and subsidiary materials of A1 to A3, and silicon carbide which is one of the antioxidants added thereto. 5%, 3%, and 0% were added in different amounts. In this case, the physical properties of each of the prepared specimens, A1 with 5% silicon carbide added showed better oxidation resistance and corrosion resistance than M, A2, A3, and the second and third tests uniformly 5% silicon carbide Added.

Figure 2 shows the change in initial strength in the hot, the decarbonization effect of the silicon carbide additive and the current product in the initial 0 to 1 minutes with the reverse strength after a certain time by directly inserting the specimen at room temperature at 1400 ℃ high temperature However, in 1 ~ 2 minutes, when the decarburization of the binder was completed, the strength of the silicon carbide additive was higher and faster than that of the current product. The above effects are achieved by adding non-oxide-based silicon carbide to the existing metal additives aluminum and magnesium / aluminum alloy, thereby reducing internal porosity and enhancing connective structure by suppressing decarburization of graphite and generating new minerals such as aluminum oxide. will be. Therefore, as a result of the primary test, the thermal properties such as oxidation resistance, corrosion resistance and hot bending strength were also improved according to the addition of silicon carbide.

3 and 4 show the second reproducibility test, and the reproducibility test was performed by applying the same amount of silicon carbide selected in the first pilot test as shown in Table 1, and the result was similar to the first test result. In terms of index, thermal characteristics such as oxidation resistance, corrosion resistance, and reverse gap strength improved by 20 ~ 30% compared to the present.

FIG. 5 shows the third varieties diversification test, and as shown in Table 1, the effects of oxidation on the oxidation resistance and corrosion resistance by changing the amounts of raw materials and subsidiary materials were mutually changed. Corrosion resistance was shown to be high, and oxidation resistance was shown in order of Example 4, Example 1, Example 3, Example 2, and comparative example in order of the raw material change, and corrosion resistance was shown in order of Example 4, Example 1, Example 2, Example 3, and Comparative Examples, the hot curvature was shown in Example 1, Example 2 was the largest, followed by Example 3, Example 4, In order of comparative example.

In the above results, even though only the highest quality raw material was used in the above results, the reason why the hot bending strength was relatively lower than that of the other various products was that the low particle size of the magnesia clinker in the kneaded material was lower than that of the other products. The result is that the sintering promotion effect by the metal additive is low.

FIG. 6 shows the change of the hot line expansion rate according to the change of raw materials and subsidiary materials.The reduction of volume expansion by the reaction product suppression and the low thermal fan rate of the material itself due to the oxidation prevention effect of other metal additives in the hot state due to the addition of silicon carbide As a result, the coefficient of thermal expansion at the hot side was low.

As a result of the three-stage test on the selection of the appropriate additive, the reproducibility test of the improved product, and the variety of varieties, the use of the appropriate amount of the additive for improving the thermal characteristics has more thermal characteristics such as oxidation resistance, corrosion resistance, and hot bending strength than the current products. There was a very good effect.

Claims (2)

Particle size 5-3㎜ Electrolytic magnesia clinker, 9 species 9-11wt%, Particle size 3-1㎜ Electrodeposition magnesia clinker, 9 species 1-11wt%, Granules magnesia clinker of 1mm or less, 14-16wt%, fine granules 1 mol of magnesia clinker, 4-6wt%, particle size 3-1mm 2 mol of magnesia clinker, 9-11wt%, 3-1mm molten magnesia clinker, 9-11wt% of molten magnesia clinker, 1mm or less 2 types 4-6wt%, particle size 3-1mm purity 98% sintered magnesia clinker 9-11wt%, fineness 98% sintered magnesia clinker 9-11wt%, purity 99% graphite 6-8wt%, 100wt% of raw material consisting of 7-9wt% of 98% pure graphite, 100wt% of aluminum, 1-3wt% of magnesium / aluminum alloy, 4-6wt% of silicon carbide, and 3-6wt of phenolic resin Magnesia-carbon support base for electric furnace tap, characterized in that consisting of a binder consisting of%. Particle size 5-3㎜ Electrolytic magnesia clinker, 9 species 9-11wt%, Particle size 3-1㎜ Electrodeposition magnesia clinker, 9 species 9-11wt%, Particle size 1-11mm, Magnesia clinker 9-11wt%, Fine 1 mol of magnesia clinker, 4-6wt%, particle size 3-1mm 2 mol of magnesia clinker, 9-11wt%, 3-1mm molten magnesia clinker, 9-11wt% of molten magnesia clinker, 1mm or less 2 kinds 4-6wt%, particle size 3-1mm purity 98wt% sintered magnesia clinker 9-11wt%, fine purity 98% sintered magnesia clinker 9-11wt%, purity 98% graphite 14-14wt% 100 wt% of raw material, an antioxidant consisting of 1-3wt% of aluminum, 1-3wt% of magnesium / aluminum alloy, 4-6wt% of silicon carbide, and a binder consisting of 3-6wt% of phenolic resin. Magnesia carbonaceous lead for electric furnace exit.