Research On Multi-axis NC Plunge Milling For Impeller

In this thesis,the geometric modeling and Numerical control(NC)machining of overall impeller are analysed and studied. The researching works include non-uniform B-Spline surface modeling of overall impeller,tool selection, nc tool path generation for the channel of impeller,post-processing. and the simulation in VERICUT. The main works are as follows:1. Build the shrouded impeller model using the algorithms of non—uniform B-spline surface and merging method of blade edge is given. Embedding Matlab7.0environment,the overall impeller can be demonstrated.2. Tool path planning method of plunge milling integrated impeller ports is presented. Based on analyzing the structural feature of impeller port, this paper comes up with an idea, that impeller can be machined in several areas. Then the method about creating different areas and the principle about choosing cutters and cutting parameters both are presented. Finally the tool path is generated after calculating path interval, path step-length and cutter axial vector.3. Using Matlab to programming some program achieving the entire abovementioned algorithm, the software module of plunge milling integrated impeller is developed.4. The post processing algorithm for5-axis machining center in Beijing Jiaotong University is presented. Then the cutting experiments are carried on after a simulation in the VERICUT, succeeding in machined integrated impeller ports. The results prove the Tool path planning method is correct.