FIREPROOF STEEL PRODUCTION METHOD Russian patent published in 2023 - IPC C22C38/50 C21C7/00 C21C5/52 

FIELD: metallurgy.

SUBSTANCE: used in the production of steels for the manufacture of metal structures, which are subject to increased requirements for fire resistance. The release of steel from the steel-smelting unit into the steel ladle is carried out at a temperature of at least 1620°C for at least 3 minutes, during tapping, calcium-containing slag-forming materials are added in an amount of at least 7.0 kg/t of steel. During secondary processing, the steel is purged with a neutral gas for at least 20 minutes, ensuring a flushing period of at least 5 minutes, and the steel is continuously cast into blanks while maintaining the temperature in the tundish ladle above the liquidus temperature by 10-45°C.

EFFECT: obtaining a workpiece from fire-resistant steel, in which the content of non-metallic inclusions does not exceed 2.5 points, with improved quality of the macrostructure.

6 cl, 3 tbl