Refractory castable for producing air blowing assisted slagging-off spray gun

Abstract

The invention discloses a refractory castable for producing an air blowing assisted slagging-off spray gun. The refractory castable includes, by weight, 40-60 parts of electric-smelting pure mullite, 15-30 parts of andalusite, 1-9 parts of aluminum oxide hollow spheres, 1-4 parts of silicon carbide, 5-10 parts of compact corundum fine powder, 5-10 parts of [alpha]-Al2O3 micro powder, 2-5 parts of silicon micro powder, 3-6 parts of pure calcium aluminate cement, and 1-5 parts of heat-resistant steel fibers. In the heavy castable, a proper amount of the aluminum oxide hollow spheres having proper diameters is introduced, so that the construction flowability of the castable is greatly improved, porosity ratio of the castable is reduced, volume density is increased and compactness of the castable is increased since the spherical shape of the hollow spheres has advantages on flowing of the castable slurry, thereby improving mechanical performance and anti-slagging performance of spray gun lining. The flexural strength of the castable is increased by 20% than that of a common castable while compression strength is increased by 45%.

Description

technical field [0001] The invention relates to the field of refractory materials for pretreatment of molten iron before steelmaking in a converter, in particular to a refractory castable for preparing an air-blowing auxiliary slag removal spray gun. Background technique [0002] After the molten iron is desulfurized, a large amount of desulfurization slag floats on the surface of the molten iron in the molten iron tank. In order to prevent harmful elements in the slag from returning to the molten iron and affecting the cleanliness and product quality of high value-added steel grades, effective means must be taken to remove these slags. Therefore, hot metal slag removal is one of the key technologies for controlling the cleanliness of molten steel, and it is also an essential means for efficient, stable, and low-cost mass production of clean steel. [0003] At present, the slag removal method commonly used at home and abroad is the mechanical slag removal method, that is, th...

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Problems solved by technology

[0005] From the above analysis, it can be known that the top-blowing lance is the key equipment for air-blowing assisted slag removal. At present, there are few studies on improving its service life, especially for the lance lining refractory material. Frequent maintenance and replacement reduces the production efficiency of the molten iron pretreatment process and increases the labor intensity of workers

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