以铅为模拟材料，对热带粗轧机组平辊立轧变形规律进行了实验研究，分析了稳定轧制阶段表征立轧时轧件断面特征的４个参量，及非稳定轧制阶段头、尾部最大狗骨高度非稳定行为，失宽行为，鱼尾长度与立辊直径、侧压量、板坯来料厚度及宽度之间的关系，并建立了新的数学模型．　 Taking lead as a model material, the rolling deformation of flat rough rolling mill in tropical roughing mill was studied. The four parameters that characterize rolling section in steady rolling stage were analyzed, and the head and tail of unsteady rolling stage The maximum instability of the dog’s bone, the behavior of widening, the relationship between the length of the tail and the diameter of the vertical roller, the lateral pressure and the thickness and width of the incoming slab, and establishes a new mathematical model.