Zirconium-silicon-chromium-based ladle stuffing sand and preparation method thereof

Abstract

The invention discloses zirconium-silicon-chromium-based ladle stuffing sand and a preparation method thereof. The preparation method comprises the following steps: mixing raw materials consisting of zircon sand, quartz sand, chromite sand and carbon black according to a certain weight ratio, and carrying out mechanical stirring, spray granulation, screening and cooling treatment to obtain target ladle stuffing sand powder. The obtained stuffing sand contains 24%-40% of ZrO2, 27%-37% of SiO2, 10%-20% of Cr2O3, 1%-8% of Al2O3, 4%-16% of Fe2O3 and less than 0.5% of H2O; the refractoriness of the stuffing sand is larger than 1850 DEG C; and the proportion of particles with particle sizes ranging from 0.1-1 mm is controlled to be 98% or above. According to the ladle stuffing sand prepared through the method, the raw materials can be fully and evenly mixed, and the influence of the segregation problem caused by uneven components on a self-opening rate is solved; and particularly, the self-opening rate of a high-quality special steel ladle with the refining time exceeding 3-8 hours is increased, and influence on the quality of molten steel caused by later oxygen burning and drainage is avoided.

Description

technical field [0001] The invention belongs to the field of making metallurgical refractory materials, and in particular relates to a zirconium-silicon-chromium-based ladle drainage sand and a preparation method thereof. Background technique [0002] Most of the domestic steel mills ladles mainly use high-chromium and silicon drainage sand, but both of them have certain shortcomings. For example, the automatic pouring rate of silicon drainage sand is relatively low, which affects the automatic Casting rates had a huge negative impact. The self-opening rate of high-chromium quicksand is better than that of silicon, but there are also problems of high cost and uneven composition. [0003] Drainage sand is made of raw material fine powder after stirring. Different material formulas and material particle sizes directly affect sintering performance and fluidity. According to the ladle’s receiving time of molten steel, steel type, etc., suitable drainage sand formula is require...

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Problems solved by technology

[0006] For some special steel mills, the refining time of special steel grades is long and the time for steel filling is long, and the self-opening rate of molten steel with a thickness of sintered layer of drainage sand is about 95%, which is difficult to increase, and the self-opening is unstable. Aspects of change, the invention proposes a zirconium-silicon-chromium-based ladle drainage sand and its preparation method

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