The temperature of steam extracted from fiveth and sixth sections of low-pressure cylinder for a 600 MW steam turbine unit in Datang Panshan Co Ltd

i.e.Panshan Power Plant

has exceeded the designed value.The main cause is due to steam leakage from the centre-dividing surface of low-pressure inner cylinder

resulting in decrease of output power and efficiency of the unit.Starting with calculation of tension force concerning flange bolts

it has been discovered that the steam leakage from low-pressure inner cylinder is resulted from remarkable deformation of the inner cylinder.For this

some measures like enhancing tension force of the flange bolts and adding sealing keys etc.have been adopted.After implementation

the temperature of steam extracted from fiveth and sixth section has decreased 25 ℃ and 40 ℃ respectively

reaching the predicted effectiveness.