Interpretation and application of the hydro-abrasive erosion model from IEC 62364 (2013) for Pelton turbines

Abstract An accurate prediction of hydro-abrasive erosion helps in design, planning and operation strategies of a hydropower plant. In the empirical erosion model from the International Electrotechnical Commission (IEC) 62364 standard, various terms such as flow co-efficient (Kf), material factor (Km) and exponent (p) were not provided for Pelton turbines components. The present paper aims to find the values of these terms and to interpret inadequately defined terms like erosion depth (S) and shape factor (Kshape) for application of IEC 62364 (2013)# model. From some field and laboratory data, the values of Kf and p were obtained for Pelton turbine components using multivariate regression analysis. The obtained values of Kf are in the order of 10−6 and 10−12 for various zones of buckets and nozzle assembly respectively whereas p values are in range 1–5. The Km values for 6 different materials, i.e. three types of chrome nickel steels, plasma and high velocity oxygen fuel (HVOF) sprayed coatings and bronze buckets were obtained as 1, 1, 1, 0.6, 0.1 and 2.2, respectively. #IEC 62364 (2013). Hydraulic machines - Guide for dealing with hydro-abrasive erosion in Kaplan, Francis and Pelton turbines. Edition 1.0 (June 2013), International Electro technical Commission, Geneva, Switzerland.