Initial residual stress experiment and simulation of thin-walled parts for layer removal method

Thin-walled parts have low stiffness characteristic. Initial residual stress of thin-walled blanks is an important influence factor on machining stability. The present work is to verify the feasibility of an initial residual stress measurement of layer removal method. According to initial residual stress experiment for casting ZL205 A aluminum alloy tapered thin-walled blank by a common method,namely hole-drilling method,three finite element models with initial residual stress are established to simulate the layer removal method in ABAQUS and ANSYS software. By analyzing the results of simulation and experiments,the cutting residual stress inlayer removal process has a significant effect on measurement results. Reducing cutting residual stress is helpful to improve accuracy of layer removal method.     

大型格子式球磨机物料动力学分析

由于进口大型球磨机资料的缺失,工程上对该型号球磨机的最佳填充率和最佳球磨转速缺乏足够的认识,以至于球磨机故障频发。为了研究球磨机转速与填充率对滚筒作用力的变化规律,并延长球磨机寿命和提高球磨效率,以球磨机滚筒内物料的运动为基础对球磨机受物料作用力进行分析,通过分析不同的填充率、不同的转速下物料对滚筒的作用载荷和分布,推导出脱离角和下落角的关系及其与滚筒受力面积的关系,并计算了不同转速、不同填充率下物料对滚筒内壁的摩擦力的分布情况。分别建立了不同转速下的下落角和脱离角模型、受载荷面积模型和滚筒受摩擦力模型。最后针对选矿厂大型格子式球磨机进行分析,并结合实际工况对各模型进行仿真分析。