宝钢湛江连铸板坯角裂的控制研究及设计实践

板坯连铸机生产包晶钢、中碳钢、含硼或铌微合金钢容易产生角裂，将导致对应的轧材出现边部翘皮和边部裂纹，为了不影响轧材质量，连铸工序必须对角裂进行火焰清理，加大了生产成本。2013年宝钢决定将罗泾两台单流2 300 mm板坯连铸机搬迁到宝钢湛江钢铁基地。原罗泾连铸机所生产板坯的角裂问题严重，针对该问题，中冶赛迪和宝钢从弯曲段辊列、扇形段辊缝精度控制、二冷分区、二冷宽度控制、动态二冷模型、动态轻压下模型等方面做了全面的优化和改进，解决了原罗泾连铸机生产板坯易产生角裂的难题，包晶钢、中碳钢、含硼或铌微合金钢板坯角裂发生率从90%以上降低到1%以下。着重阐述在设计阶段针对角裂问题所做的工作。

Study on control of corner cracks in cast slabs and its application to designing of continuous slab casters of baosteel Zhanjiang

Corner cracks are very likely to occur in the slabs when peritectic steels， medium carbon steels， boron or niobium micro-alloyed steels are being produced by continuous slab caster， which will lead to edge upwarping and edge cracking of the finished products in the rolling process. To stop the slabs with corner cracks from going down to the rolling mills and affecting the finished rolled product quality， the slabs must be flame scarfed in the continuous casting process， thus causing increases in the operational cost. In 2013， Baosteel decided to relocate the two single-stream 2 300 mm slab casters from Luojing of Shanghai to Zhanjiang of Guangdong. The slabs produced by the slab casters at Baosteel Luojing were observed with serious corner crack problem. To tackle corner cracks， CISDI worked hard together with Baosteel to extensively optimize and improve the bender roller arrangement， segment roller gap accuracy control， secondary cooling zoning， secondary cooling width control， dynamic cooling control model， dynamic soft reduction model， etc.， and eventually the conundrum of corner cracks which were frequent in the slab casters when at Luojing was solved and the occurrence of corner cracks in slabs of peritectic steels， medium carbon steels， boron or niobium micro-alloyed steels was decreased from over 90% to less than 1%. Article focuses on the work done specifically on tackling of corner cracks in the designing stage.