Corrosion of steam turbine bladings -A case study

Corrosion of turbine blades considerably reduces the economy of power generation. The chances of early failure of turbine blades in modern power plants are minimised by the use of corrosion resistant alloys and proper treatment of boiler feed water. A case of failure of turbine bladings at Mithapur, situated on the sea coast was referred by Messrs Tata Chemicals Ltd. for investigation. Various tests were made and different operating conditions were studied. From the investigation carried out it was concluded that the attack was probably due to the deposition of chloride on the turbine blades from the atmosphere during stoppage when the hot air was used for drying the blades. (Mr. K.P. Mukherjee, Senior Scientific Assistant; Mr. A.K. Lahiri, Senior Scientific Officer and Dr. T. Banerjee, Dy. Director, National Metallurgical Laboratory)