共查询到15条相似文献,搜索用时 109 毫秒
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结合连铸坯凝固理论和异型坯在结晶器内以及二冷段所受的应力,分析了异型坯这种独特断面铸坯表面裂纹和内部裂纹的形成机理。根据机理分析对异型坯的冷却制度和保护渣理化性能进行适当优化。通过降低结晶器和二冷段的冷却水量,增大结晶器保护渣粘度等措施,减少了异型坯裂纹的产生。 相似文献
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针对H型钢“V”形开裂问题,研究了连铸异形坯存在的质量缺陷,对同类连铸生产具有参考与借鉴意义。H型钢由异型坯轧制生产而成,其比表面积较大,通过连铸生产时铸坯表面冷却强度极不均匀,各面受力情况较为复杂,而对其整个生产工艺流程及质量控制方面均有较高要求。以新泰钢铁公司实际生产中发生轧制开裂的Y Q235B连铸坯为研究对象,通过对缺陷铸坯进行重熔检测,采用ANSYS软件与现场检测相结合的方法,分析了铸坯表面纵裂纹的形成原因及控制方法。结果表明,H型钢V形开裂的主要原因是由腹板和R角处的纵向裂纹造成的,而形成纵向裂纹的主要原因是冶炼过程中控制不合理,精炼脱不够;连铸过程中不能有效地控制和去除夹杂物;铸坯环向温度梯度过大,造成腹板和R角处冷却极不均匀,应力应变过大。通过采取优化改进工艺后,异型坯轧制出现V形开裂比例由原先的80%降低至5%以下,产品质量大幅提升。 相似文献
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介绍了连铸坯表面纵裂纹的成因及特征,从钢水成分、连铸机拉速、保护渣液渣层厚度和结晶器液面波动、结晶器冷却效果和二次冷却方面,提出了防止连铸坯表面纵裂纹的具体措施。 相似文献
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《钢铁冶炼》2013,40(5):377-386
AbstractA two-dimensional heat transfer model was developed for the secondary cooling system during beam blank continuous casting. The finite element method was used to calculate the heat transfer. Accurate cooling boundary conditions in the secondary cooling zone are involved, including spray water cooling, water evaporation cooling, radiation cooling and roll contact cooling in the casting direction and non-uniform distribution of spray water flow density in the cross-section. The causes of longitudinal crack at the fillet during Q235 steel continuous casting were analysed on the basis of the simulation of the developed model, and then the spray water flow and the transverse nozzle layout were optimised. Practical results show that the surface quality of the beam blank improved after optimisations. Numerical results from the present model were validated using previous experimental measurements, which show good agreement. 相似文献
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