Application of ACC/DEC interpolation algorithm in steam turbine blade NC machining

To satisfy high speed and high precision machining for steam turbine blade, an improved acceleration/deceleration (ACC/DEC) interpolation algorithm based on the NURBS curve is proposed as the blade curvature radius changes greatly. The interpolation algorithm in this paper takes the easily overrunning chord error and maximum acceleration into consideration, and uses ACC/DEC control in the sensitive area of feeding speed mutation, it makes feed speed meet the ACC/DEC demand and adjust with the curve curvature changes. So the machining precision is improved and the impact on machine is reduced significantly. The experimental results show that the interpolation algorithm can not only ensure the processing efficiency and precision, but also realize the smooth transition of speed.