单位生产成本与加工精度的多工序车削优化

Multi-pass Turning Optimization of Unit Production Cost and Machining Accuracy

切削参数优化对于加工质量、生产效率、加工成本、产品利润具有非常重要的意义。数控加工过程中,单位生产成本和加工精度很大程度上决定了零件加工成本的高低和加工质量的好坏。建立以单位生产成本与加工精度为双目标的多工序车削优化模型进行切削参数优化选择十分必要。多工序车削模型同时充分考虑了粗精的刀具耐用度、切削功率、切削进给力、稳定切削区域、刀具表面切削温度及精车表面粗糙度等实际约束条件。运用高斯变异和多项式变异的NSGA-II算法对多工序车削模型进行比较优化计算,优化实例表明多项式变异的NSGA-II算法获得了更好的加工精度、单位生产成本的Pareto最优解集以及相应的粗精切削参数。用多项式变异的NSGA-II算法得到的优化粗精切削参数进行切削试验,得到与NSGA-II算法优化的加工精度、单位生产成本基本相符,为多工序车削切削参数优化提供了实践指导。

The optimization of cutting parameters is very important for machining quality, production efficiency machining economics and production profit. In the NC process, Unit production cost and machining accuracy have a large effect on production cost and machining quality of machining work-piece. A bi-objective multi-pass turning optimization cutting model, based on unit production cost and machining accuracy, is very necessary. Various practical constraints is considered in the nonlinear cutting optimiza- tion model, including bounds for tool-life, cutting power, cutting force, chip-tool interface temperature, stable cutting region in rough and finish machining and surface roughness in finish machining. The Non- dominated Sorting Genetic Algorithm-II （NSGA-II） with gauss mutation and polynomial mutation is ap- plied to the bi-objective nonlinear constrained optimization cutting model. Example results of NSGA-II with polynomial mutation are obtained the better machining accuracy, unit production cost and corre- sponding cutting parameters, under the Pareto-optimal solutions set for the cutting model. Cutting experi- ment results using the presented optimization machining parameters data by the NSGA-II with polynomial mutation are tested, the machining accuracy and unit production cost obtained correspond to the data of the optimization machining accuracy and unit production cost, which provides practical guides for optimi- zation of machining parameters in multi-pass NC turning.