复杂曲面内腔铣削粗加工分层方法优选

Optimization of Layering Method for Rough Machining of Complex Surface Cavity Milling

大推力涡扇发动机、燃气轮机等国家战略装备引擎广泛使用复杂曲面内腔类零件,该类零件具有侧壁扭曲、整体内扣、深窄等结构特点,难以采用传统平面分层铣削方法高效加工制造。为攻克该类零件的高效加工制造难题,根据该类零件的结构特点和分层铣削加工的基本原理提出一种通过等距偏置线划分铣削层的方法,简称等距偏置分层法。首先,以等距偏置分层法和平面铣削层划分方法为基础分别规划复杂曲面内腔粗加工工艺方案;其次,进行数控仿真和加工实验,随之对比分析两种分层方法的优缺点;最后,使用工艺方案评价模型选出更适合复杂曲面内腔粗加工的分层方法。经计算,等距偏置分层法的评价结果(Evaluation Results,ER)为0.99028,高于平面分层法的评价结果0.77291,这表明等距偏置线分层方法更适合复杂曲面内腔的高效粗加工。

Complex curved surface inner cavity parts are widely used in national strategic equipment engines such as high thrust turbofan engines and gas turbines.These parts have structural characteristics such as sidewall distortion,overall internal buckle,and deep and narrow,making it difficult to efficiently manufacture them using traditional methods.To overcome the efficient machining difficulties of this type of part,a method of dividing milling layers through equidistant offset lines is proposed in this paper,abbreviated as equidistant offset layering method,based on the structural characteristics of this type of part and the basic principle of layered milling.In the paper,the equidistant offset layering method and the plane milling layer division method are used as the basis to plan the rough machining process plan for the inner cavity of complex surfaces.Then,numerical control simulation and machining experiments are carried out,and the advantages and disadvantages of the two layering methods are analyzed and compared.Finally,the process scheme evaluation model is used to select a more suitable layering method for rough machining of complex curved surfaces inner cavity.After calculation,the evaluation result value of the equidistant offset layering method is 0.99028,which is higher than the value of the planar layering method,which is 0.77291.The evaluation results indicate that the equidistant offset line layering method is more suitable for efficient rough machining of complex surface inner cavity.