热轧带钢R2粗轧机下主传动轴断裂有限元分析与应用

以某2250热轧带钢厂R2粗轧机承受较大载荷的下主传动轴为研究对象,采用Marc软件建立了该传动轴薄弱区段弯扭应力分析三维有限元模型.扭转、弯曲和弯扭联合作用等不同载荷条件的有限元分析表明:不同工况下传动轴在托架支持的局部轴段的缩颈导致该处应力比非缩颈处的应力增加约60%;异常扭矩是造成传动轴产生裂纹和断轴的主要原因;采取将传动轴缩颈区段改为实心区段的加固措施可减小最大扭矩应力值21%.改进后的具有裂纹的传动轴已成功应用于粗轧机的正常轧钢生产.

Breakage mechanism and application of the bottom main drive spindle in a R2 roughing mill during hot rolling by finite element analysis

With special supporting structure for heavy loading, a bottom main drive spindle's breakage appears in strip production of the R2 roughing stand in a 2 250 mm hot strip mill. Based on the Marc software package, a 3-dimensional finite element model was constructed to analyze the combined bend and torsion stress state of a bottom main drive spindle in the R2 roughing mill. Under different loading situations of torsion, bending or both them, the results of finite element analysis show that the stress in the special supporting area is greater 60% than that in other normal areas of the spindle in different computing cases. It is also shown that torque is the main reason leading to cracking and breakage of the spindle. The maximum stress in the main drive spindle supporting area after replacing original hollow structure with improved solid structure is reduced by 21%. The reinforced main drive spindle was successfully applied in production of the roughing mill.