Assessment of erosive wear of Pelton turbine injector: Nozzle and spear combination - A study of Chenani hydro-power plant

摘要

This study concerns with erosion of Pelton turbine injector i.e. (nozzle spear tribo pair) by sediment particles for a typical power plant located in Himalayan belt of Jammu and Kashmir in India. Erosion of hydro turbine/runner and its allied parts by the sediment particles suspended in the river water is one of the challenging problems (faced by maintenance personnel of hydro power plants). Injector assembly is subjected to severe erosion which renders it dysfunctional in relatively short span of time compared to other parts of the hydro power plant. A detailed study regarding erosion measurement has been conducted using novel technique of 3D optical scanning to assess material loss and identify type of wear for spear and nozzle combination used at Chenani power plant (5 units each with a 4.66 MW capacity). Hydro-abrasive wear was quantified on the basis of measurement of material removed by process of erosion on spear and nozzle (virgin parts) compared with weight of eroded parts (scanned). The erosion was found to be 3.71% and 5% on spear and nozzle respectively (of virgin volume).