Silt erosion has been major concern in hydro turbine components situated in the Himalayan region of India. This happens due to presence of quartz particle in the water. Especialy during rainy season, the concentration of quartz particle goes up and accelerate the erosion process. Several approaches have been adopted to reduce this problem like, plasma nitridin, high velocity oxy fuel (HVOF) coating of WC-Co, etc. HVOF coating has been successful in many of the sites. Disadvantages of this coating is its high cost. In this paper we have explored a suitable coating made of polyurethane. This coating has been further modified with hard fine powders and nitride and carbide. Erosion test results show that the polyurethane (PU) coating modified with carbide based pwder is suitable for preventing silt erosion problem in the hydro turbine. Cost wise it is highly economical than HVOF coating. This polyurethane coating can be adopted in all the low head hydroturbine where silt erosion is a major concern.
