锥台复合截面环件精密轧制毛坯的优化设计方法

Optimization design on precision rolling blank for conical ring with outer step

针对广泛用于油气管道阀门、航空发动机机匣及结合环中的锥台复合截面环件较难同时获得所需的直径尺寸和台阶形状的问题,提出"等壁厚型"和"变壁厚型"两种环坯设计方法。借助ABAQUS模拟平台,建立两种轧制环坯设计下的锥台复合截面环件轧制过程的有限元仿真模型,分析两种环坯轧制过程中的台阶充型规律及最终的成形环件尺寸误差。结果表明,"变壁厚型"环坯比"等壁厚型"环坯轧制成形后尺寸精度高。为获得最优的尺寸精度,在"变壁厚型"环坯设计基础上,添加尺寸修正系数η。通过对比不同修正系数η下的环坯轧制成形尺寸精度,得出尺寸修正系数η在1<η<1.1范围内的"变壁厚型"环坯为最优环件轧制毛坯。基于模拟结果,在WD51Y-250多功能轧环机上进行锥台复合截面环件轧制实验,验证有限元模拟的可靠性和环坯设计方案的可行性。

The conical rings with outer step is widely used in oil and gas pipeline valves,bearings and aircraft engine casings. Since it is difficult to obtain the required diameter size and step shape simultaneously,two kinds of ring blanks with equal wall thickness and variable wall thickness were designed. Then,their rolling process was simulated by the ABAQUS,and the step filling law and the dimension errors of the rolled ring were analyzed. The results show that the dimension precision of rolled ring with variable wall thicknesses ring blank is higher than that of rolled ring with equal wall thickness ring. Therefore,the size correction coefficient η is added to obtain the optimal dimension precision based on the variable thickness design. Finally,by comparing the dimensional precision of rolled ring under different correction coefficients η,the optimal correction coefficient is within 1 〈η〈 1. 1. According to simulation result,related rolling experiments were carried out in WD51Y-250 ring rolling mill to verify the reliability of FE simulation and the feasibility of the design method of blank with variable wall thicknesses.