薄板坯连铸高强钢700L工艺优化

Continuous Casting Process Optimization of High-strength Steel 700L Thin Slab

为了解决唐钢FTSC薄板坯连铸在浇铸700L钢种过程出现的质量问题,首先通过对薄板坯连铸坯壳在漏斗型结晶器内受力情况和FTSC(Flexible Thin Slab Casting)二冷喷水布置的分析,同时结合钢种特性分析了700L钢种出现表面裂纹和铸坯内裂的原因。根据上述分析结果对连铸结晶器锥度、结晶器水量、中包过热度、保护渣、二冷水等工艺进行了优化,试验结果表明:通过增加开浇锥度,降低结晶器水量,降低中包过热度,调整保护渣粘度和碱度参数,降低连铸二冷水中喷水量等措施有效解决了薄板坯连铸高强钢的表面裂纹和铸坯内裂缺陷,优化后试制过程热相图稳定,铸坯表面质量、内部质量良好,本研究为薄板坯连铸产线浇铸高强钢提供了理论基础和实践经验。

In order to solve the quality problems of 700 L thin slab during Tangshan iron and steel company FTSC continuous casting,force situation of solidification shell in funnel-typed mold and FTSC( Flexible Thin Slab Casting) spray of secondary cooling was analyzed for thin slab continuous casting,at the same time,according to the characteristics of steel,the causes of surface cracks and internal cracks of 700 L steel was analyzed in this paper.The mould taper,mould water,tundish superheat,mould powder,secondary cooling water etc processes were optimized based on the above analysis results.The results showed that surface cracks and billet internal crack of continuous casting high strength steel thin slab were effectively solved by increasing the opening taper,reducing mould water quantity,reducing tundish superheat,adjusting the viscosity and basicity of mould powder,reducing fountain volume of secondary cooling water. Through the process optimization,heat phase diagram is stabilized,surface and internal quality of thin slab are improved.