Model-Based Monitoring and Control of Continuous Dress Creep-Feed Form Grinding

This paper is concerned with process monitoring and control of Continuous Dress Creep-Feed (CDCF) form grinding using model-based simulation and in-process power measurement and its application to grinding of turbine blade root serrations. For blade root serration grinding, it is essential that the grinding force be maintained below a critical limit to avoid cracking of the Thermal Environmental Barrier Coating (TEBC) at the blade airfoils, and that the heat flux at the grinding zone be kept below the fluid burnout limit to avoid thermal damage to the part. A blade root form grinding process is first simulated and optimized by utilizing the variable-feed approach developed previously, whereby both the dress infeed and part feed rate are adaptively varied to minimize cycle time while maintaining the force and heat flux below specified limits. Both the grinding forces and heat flux are obtained from the measured power. Maintaining the monitored power signature from production processes within the acceptable power limits established in this way ensures a “normal” grinding process. Deviations from the normal process signature profile indicate possible process issues.