Abstract: With controlling sulphur content in steel≤0.020%,temperature fluctuation range of molten steel of df- ferent heat in tundish decreasing to 10 ℃ from original 25 ℃,adjusting mold water rate to 190～200 m³/h,controling casting rate0.55~0.75 m/min,the intemal crack reject rate for 260 mm×300 mm cast billet of steel 20CrMnTiH, 40Cr, CCr15 etc decreased to 0.01% from original 0.30%,in order to basically eliminate the intemal crack in cast billet.

Key words: 260 mm×300 mm Concasting Billet, Intemal Crack, Casting Rate, Molten Steel Temperature in Tundish

摘要： 通过控制钢中硫含量≤0.020%,不同炉次中间包钢水温度波动范围由25 ℃降至10 ℃,调整结晶器 水量为190~200m³/h,控制拉速0.55~0.75 m/min, 使20CrMnTiH 、40Cr、GCr15等钢种260 mm×300 mm连俦坯的内裂废品率由0.30%降低到0.01%,基本消除了铸坯内裂纹。

关键词: 260 mm×300 mm连铸坯, , 内裂纹, 铸速, , 中间包钢水温度