Development of Cobalt-Based Welding Material with Anti-Cavitaion Erosion Performance for Hydraulic Turbine

Abstract

In hydraulic turbine runner, overlay welding repair is usually required for cavitation erosion. To improve the operating time and to avoid repetitive welding repair, we developed Cobalt -based welding material with anti-cavitation erosion performance to improve toughness by change of chemical composition. This developed welding material is classified into fluxcored wire. This welding material has applied to hydraulic turbine runner which had been high cavitation erosion resistance (decrease to 1/10) that compared with 309 stainless steel. We confirmed that according to visual observation after longterm operation, cavitation erosion of hydraulic runner was properly controlled by Cobalt-based welding material.