Composite air brick and argon blowing refining method in continuous casting ladle pouring process

Abstract

The invention relates to a composite air brick and an argon blowing refining method in a continuous casting ladle pouring process. The air brick comprises a pouring body, a dispersion block and a safety warning device, wherein the dispersion block and the safety warning device are arranged in the pouring body from top to bottom; a plurality of slit air channels A penetrating through the dispersion block are vertically formed in the dispersion block; a lower air chamber is arranged at the bottom of the safety warning device, an upper air chamber is arranged at the top of the safety warning device, a plurality of slit air passages B which are through up and down are arranged in the safety warning device, the plurality of slit air passages B are uniformly distributed in the safety warning device along the circumference, and the lower ends of the slit air passages B are gradually inclined outwards; and the slit air passage A, the upper air chamber, the slit air passage B and the lower air chamber are communicated. The air brick has the excellent performance of large air permeability, stable air permeability, long service life and the like, after refining treatment in an LF refining furnace is completed, the air brick is hoisted to a continuous casting rotary table, argon blowing is carried out in the continuous casting steel ladle pouring process to remove inclusions, the soft blowing time in the later stage of LF refining is shortened, the removal rate of the inclusions is increased, and molten steel standing layering is restrained.

Description

technical field [0001] The invention relates to a compound air-permeable brick and argon-blowing refining method in the pouring process of continuous casting ladle, belonging to the technical field of steelmaking process in iron and steel metallurgy. Background technique [0002] Argon blowing at the bottom of the ladle is a simple and efficient refining technology outside the furnace, which is widely used at home and abroad. Ladle bottom blowing air brick mainly has two structural types: diffuse type and slit type. In actual production, there are the following problems or deficiencies: (1) The slit type air brick has a large air volume and good argon blowing and stirring effect, but the argon blowing form The argon bubbles in the argon bubbles are large, which affects the metallurgical effect of the argon bubbles to remove inclusions, while the diffused air permeable bricks breathe through the diffusely distributed air holes, and the air flow is small and unstable, which af...

AI Technical Summary

Problems solved by technology

Ladle bottom blowing air brick mainly has two structural types: diffuse type and slit type. In actual production, there are the following problems or deficiencies: (1) The slit type air brick has a large air volume and good argon blowing and stirring effect, but the argon blowing form The argon bubbles in the argon bubbles are large, which affects the metallurgical effect of the argon bubbles to remove inclusions, while the diffused air permeable bricks breathe through the diffusely distributed air holes, and the air flow is small and unstable, which affects the stirring and mixing effect of argon blowing. The argon bubbles formed by argon are small, and the metallurgical effect of argon bubbles to remove inclusions is better, because the service life of the diffused air permeable brick is low, which seriously affects the service life of the ladle lining and the cost of refractory materials, and it is difficult to popularize and apply; (2) LF refining The soft blowing time in the later period is long, and the pouring time of the large-section billet is relatively shortened. If the refining time is not shortened accordingly, the molten steel for the continuous casting machine will not be connected, and the continuous casting machine will drop. speed, that is, it will cause the mismatch problem of furnace and machine, and become the limiting link for the increase of steelmaking production capacity.

However, the invention has the following problems or deficiencies: both the diffused venting plug and the safety warning device are in the shape of a truncated cone. The line is out of service, causing steel penetration and steel leakage accidents in the ventilated bricks, and there is a greater risk of safe use; the diffusion-type ventilated bricks are prone to transverse fractures due to the poor connection effect of the diffused vent holes, and the air flow is unstable, which directly affects the argon blowing and stirring The effect of mixing molten steel causes the temperature and composition of molten steel in the ladle to be uneven, which affects the homogenization and quality stability of molten steel

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