The effectiveness of flow passage retrofit for high and medium cylinders of former soviet-made steam turbine equipped for 215MW unit in Zhangze Power Generation Branch Company has been explicated.Through retrofit

the efficiency of high pressure cylinder and of medium cylinder reaches 84.43% and 93.94% respectively

and the specific heat consumption reaches 7 989.4 kJ/(kW·h).Under operating condition of pure condensation

the heat consumption rate decreases 337 kJ/(kW·h)

the coal consumption rate reduces 12.7 g/(kW·h)

the standar coal can be saved fifteen thousand tons per year

the capital investment in retrofit can be taken back within two and a half year.Under operating condition of heat supply

the maximum extract steam flow rate reaches 340 t/h

the coal consumption rate can be reduced 20 g/(kW·h) and more.