A Study Of Multi-Axis Machining Of Centrifugal Compressor Impellers

       The centrifugal compressor impeller is an important component in the field of aerospace and precision machine industry. Traditionally, there have been two methods for manufacturing the impellers : casting and machining. Both methods have advantages and disadvantages, respectively. Due to the complex geometry of the centrifugal compressor impellers, it is a challenging technology to machine the impellers.
       Referring to the machining technology, there have been two cutting strategies : point cutting and flank cutting. Based on the consideration of cost, efficiency, and surface roughness, flank cutting is a promising way to machine the blade surfaces of impeller by using a 5-axis machining center with two more degrees of freedom than the traditional 3-axis machining center. However, the complexity of the tool paths generation increased with the flexibility of the used equipment.
       In this thesis, a flank cutting technology for centrifugal compressor impellers is proposed by using the B-spline curve interpolation, ruled surface construction, and coordinate transformation. And an impeller is machined actually to verify the proposed method. In addition, a windows-interfaced CAD/ CAM software is developed to make the 5-axis NC code generation more easily and friendly.