JPH0517191B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention is a filling material for the lining joints of molten metal containers including molten steel refining ladles, and more specifically, a method for filling the lining joints of molten metal containers including molten steel refining ladles, and more specifically, for filling materials for the permanent bricks on the back surface that occur when carbon-containing bricks are used for the side walls of molten metal containers. This invention relates to a joint filler that solves the problem of fusion. [Technical background] Magnesia carbon and other carbon-containing bricks were initially used for slag lines in refining ladles due to their excellent corrosion resistance and spalling resistance, but in recent years, they have also been used for laying and walls. It expanded to the hot water area, and then came to be applied to the entire wall area. Carbon-containing bricks have high thermal conductivity, which increases the heat load exerted on the back surface and causes fusion with permanent bricks. For this reason, when carbon-containing bricks are used as linings, this fusion phenomenon makes it difficult to dismantle them after use, and the permanent bricks must be repaired even after disassembly. Therefore, even if the service life is increased by using carbon-containing bricks,
There is a problem in that it is disadvantageous in terms of container usage turnover rate, dismantling, and repair costs. This fusion phenomenon occurs when permanent bricks with relatively low fire resistance become semi-molten due to a large heat load, and slag that enters through the gaps in the joints of wear bricks enters the boundary of the permanent bricks in a molten state due to a high heat load. This is due to the two factors of fusing the two. In addition, loosening of horizontal joints is caused by the high expansibility of carbon-containing bricks, especially mag carbon bricks. [Object of the Invention] The present invention takes into consideration the above-mentioned factors regarding the fusion phenomenon of wear bricks and permanent bricks, and
The purpose of the present invention is to provide a spherical dry filler containing graphite and having good fluidity. [Structure of the Invention] The lining joint filler for a molten metal container of the present invention includes:
A granulated product consisting of a compound containing 3 to 50% by weight of natural phosphorous graphite or other carbon source and 50% by weight or less of an alumina raw material, with the remainder being a magnesia raw material, and the blend is granulated with the addition of a granulating agent. Consisting of grains,
And 80% by weight of granules with a particle size distribution of 3 to 0.2 mm.
It is characterized by occupying more than The first feature of the filler according to the present invention is its form, which is that it is a dry type of spherical particles with a relatively narrow particle size distribution of 80% by weight or more of particles of 3 to 0.2 mm. If the number of particles larger than 3 mm is larger than this, the filling properties during construction will be lacking, and if the number of particles smaller than 0.2 mm is large, the fluidity will be poor. This gives it superior fluidity compared to conventionally used mortar. Therefore, it is possible to perform construction using a push rod, and it is possible to obtain a joint construction body that is easy to construct and has excellent filling properties. The second feature is its composition, in which the main aggregate is magnesia containing 3 to 50% by weight of natural scaly graphite and other carbon. For this reason, it is possible to obtain a filler with excellent slag resistance and slag permeability, but if the amount of carbon exceeds 50% by weight, the granulation efficiency is poor and the construction body becomes highly thermally conductive, so the permanent bricks behind the If the amount is less than 3% by weight, the slag resistance and slag penetration suppressing effect will be poor. With the same composition, natural and artificial alumina raw materials are added. This provides expandability during spinel formation, extrudes wear bricks toward the molten steel, and as a result, it is possible to tighten the joints and prevent joint opening. However, if the amount added is excessive, there will be a problem of decreased slag resistance, so the amount added should not exceed 50% by weight. In preparing the filler of the present invention, an appropriate amount of a phenolic resin or other granulating agent is added to the composition having the above composition, and the mixture is granulated using a high-speed Eirich mixer. It is possible to obtain granules that are spherical in shape and contain less fine powder. [Example] Examples of the filler of the present invention and their characteristics are shown in the attached table. The filler shown in Example 2 in the attached table was used to fill the joints of a special steel refining ladle shown in the attached figure. The filler is filled with a push rod into the joint (3) between the permanent brick (1) made of syamoto and the MgO-C wear brick (2) made of 13% by weight of carbon and 74% by weight of MgO. When used under operating conditions of 1650°C, there was no fusion phenomenon even after 110 charges, and joint opening and joint wear during use were significantly reduced.

【table】

〔Effect of the invention〕

Since the filler of the present invention is a spherical dry granule, it has superior fluidity compared to mortar having a fine powder composition, is easy to apply, and has excellent filling properties. Furthermore, the construction body itself has excellent slag properties and slag permeability, and has the effect of tightening the joints and preventing them from opening. In addition, since it contains carbon and is spherical in shape and contains little fine powder and is difficult to sinter, it has the effect of improving releasability from permanent bricks when dismantling used wear bricks.

[Brief explanation of drawings]

The attached figure shows a metal container provided with a filler according to the invention. 1... Permanent brick, 2... Wear brick,
3... Joint area.

Claims (1)

[Claims] 1 Natural phosphorous graphite or other carbon source 3-50
A lining joint filler for a molten metal container made of a compound containing 50% by weight or less of an alumina raw material and the remainder being a magnesia raw material, the compound being granulated with the addition of a granulating agent. A lining joint filler for a molten metal container, comprising granules and having a particle size distribution in which granules of 3 to 0.2 mm account for 80% by weight or more.