| 摘要 |
FIELD: processes and equipment for making steel castings with small quantity of surface blisters, internal flaws and having solidified structure with similar size of grains. SUBSTANCE: invention is designed for casting chrome-containing steel with small quantity of surface blisters and internal flaws and with fine solidified structure and for making seamless steel tubes of such steel. According to invention steel casting with improved workability has zone where at least on area equal to 60% of its cross section there are equiaxial crystals with diameters (mm) satisfying to next expression D<1,2X1/3+0,75, where D - diameter (mm) of different equiaxial crystals of internal structure having crystals of the same orientation; X -spacing (mm) from surface of steel casting until crystal. Steel casting and steel material have lowered quantity of surface and internal defects. EFFECT: improved quality and workability of steel due to intensified growth of solidified seeds, cleaned structure of solidified ingot or casting of melt steel subjected to decarburizing purification. 34 cl, 20 dwg, 12 ex, 14 tbl |
