连铸方坯脱方及表面缺陷的成因与对策

Cause to Breakout of Continuous Casting Billetand Surface Defects and Counter Measures

连铸方坯脱方根源在于钢水在结晶器内受到不均匀冷却、结晶器水缝、锥度影响显著，保护渣性能不匹配使铸坯表面产生凹坑，浇注控流、脱氧不良引起水口结瘤形成铸坯接痕，采取相应措施后取得了较好效果。

The root cause to the breakout of the continuous casting billets lies in the nonuniform cooling of liquid steel inside the mould, existence of water seam in the mould, heavy influence of mould taper and incompatibility of flux slag, which brought about concave pits on the surface of the billets. in the meanwhile control of strands and insufficient deoxidization in casting operation could probably lead to build-up of inclusion at the nozzle gate, thus causing surface defects of the billets. Good results have been achieved upon implementation of the appropriate counter measures.