中板峰裂的研究与控制

Research and control of mountain cracks on medium plate

中板表面峰裂是造成非计划改判的主要原因,通过系统的调查分析,认为该缺陷来源于铸坯内弧的横裂纹。造成横裂的原因除与钢种的化学成分有关外,还与保护浇注,设备保证性能有关。通过优化成分设计,提高保护浇注效果,保证连铸关键设备如结晶器、振动台、扇形段的控制精度能有效减少横裂纹的产生。

The peak shaped cracks on the surface of the medium plate is the primary cause to the substandard rate of the steel products. On the basis of systematic investigation and analysis it＇s proved that the defect originates primarily from the transversal crack of the inner bow of the slab and the causes to the crack are closely related not only to the chemical compositions of the steel grade, but also to the conditions of the protec- tive casting and performance of the equipments. The transversal cracks of the slab can be reduced effectively by optimization of the composition design, improvement in the effect of the protective casting and guarantee of the control accuracy of the key equip- ments of the continuous caster such as mould, vibration table and segments.