Interpolation Algorithm for Stream Turbine Blade in High Speed and High Accuracy CNC Machining

To improve machining quality and the efficiency of steam turbine blade, mathematics model of complex blade is built with non-uniform rational B-spline (NURBS). An interpolation algorithm based on redundancy error for blade is proposed according to blade curvature radius great change. The faster feed speed is adopted to increase the machining efficiency when the blade curvature radius is big. The feed speed is adaptive to control the chord error within the specified range when the blade curvature radius is small. The experimental results are provided that the machining efficiency of blade is not only improved, but also the contour accuracy is guaranteed with the interpolation algorithm based on redundancy error.