High speed machining with a robot for hydraulics turbine maintenance

Removing material by grinding in damage areas is one task manage for hydraulics equipment maintenance. These operations are currently carried out manually and are difficult in the long run. EDF R&D analyzes the need and demonstrates the feasibility of mechanizing the machining operations done in the workshops. EDF R&D experience of hard material high speed machining with a 6-axis anthropomorphic robot has been utilized. Feasibility studies have been carried out in several steps, and coordinated with final users needs. The first one was dedicated to define the size of a system being compatible with components to be repaired. Accessibilities to areas to be maintained were studied using Computer Assisted Design models. The second step consisted in having feasibility demonstrations on representative components. Feasibility of high speed milling with robot on stainless steel Kaplan turbine blade and on copper-aluminum alloy Francis turbine runner were managed to validate milling parameters and accessibility.