摘要:叶轮类零件是一类具有代表性且造型比较规范的、典型的通道类复杂零件,其形状特征明显,工作型面的设计涉及到空气动力学、流体力学等多个学科,因此曲面加工手段、加工精度和加工表面质量对其性能参数都有很大影响。故叶轮的设计与制造密不可分。传统的叶轮加工方法是叶片与轮毂采用不同的毛坯,分别加工成形后将叶片焊接在轮毅上。此方法不仅费时费力,且叶轮的各种性能难以保证。近年来,多轴数控技术尤其是五轴数控技术的发展使得叶轮的整体加工成为可能并日益普及。8011
UG实体建模,通过拉伸、旋转、扫描等建模方法,并辅之以布尔运算,使用户既可以进行参数化建模,又可以方便地使用非参数方法生成三文模型。另外还可以对部分参数化或非参数化模型再进行二次编辑,以方便生成复杂机械零件的实体模型,具体有以下优点。UG实体建模充分继承了传统意义上的线、面、体造型特点及长处,能够方便迅速地创建二文和三文线实体模型。而且还可以通过其它特征操作和特征编辑模块对实体进行各种操作和编辑。将复杂的实体造型大大简化。UG实体建模能够保持原有的关联性,可以引用到二文工程图、装配、加工、机构分析和有限元分析中。
数控加工是CAD/CAM技术中的重要环节之一,刀位轨迹规划又是数控加工技术的关键,本论文也重点讨论了整体叶轮零件的刀位轨迹规划问题。首先,给出了毛坯的制备、定位基准及加工路线的拟定、刀具类型和切削参数的选择;然后介绍了整体叶轮零件粗加工阶段的刀轨规划,采取分层渐进的方式对毛坯进行分层铣削;最后分析了整体叶轮叶片曲面的局部曲率变化特征,以相对于驱动面方式规划精加工刀轨。由于叶片空间重叠区域大,在加工过程中,重点考虑了刀轴矢量的控制,在UG上完成整体叶轮零件的模拟加工过程。
关键词: 整体叶轮 B样条曲线 直纹面 刀位规划 仿真
Geometric modeling and five-axis NC machining of Integral impeller based on UG NX
Abstract: The impeller parts is a class representative and relatively standardized modeling the typical channel complex parts, shape characteristics, the design of the work surface comes to aerodynamics, fluid dynamics, and other disciplines, surface machining means of machining precision and surface quality has a significant impact on its performance parameters. It is inseparable from the design and manufacture of the impeller. Traditional impeller machining blades and hub rough after blade welding, shaping the wheel Yi. This method is not only time-consuming, and the various properties of the impeller is difficult to guarantee. In recent years, multi-axis CNC technology, especially the development of the five-axis CNC technology makes the overall processing of the impeller become possible and the growing popularity.
Overall impeller is widely used in aerospace and other fields as the key components of the power machinery, processing technology has been an important topic in the manufacturing industry. It can be seen from the overall geometry of the impeller and process the integral impeller machining, the machining trajectory planning constraints is more, the space between the adjacent blades is smaller processing Collision easy to produce, automatically generated without interfere with the machining path more difficult. Accordingly, in the process of processing the impeller, not only to ensure that the machining path of the blade surface is able to meet the requirements of geometric accuracy, but somewhat limited due to the thickness of the blade, but also in the actual processing Note trajectory planning in order to maintain the quality of processing. At present, the majority of the majority of our production impeller manufacturers using large CAD / CAM software is completed, the following will be used specifically for impeller machining module in NX 7.5 in practical application.