Abstract: Bearing pedestal and foundation stiffnesses by finite element were analysed，the data of bearing support stiffnesses for a 1000MW nuclear power TG set was obtained. The influence of different bearing stiffness on the turbogenerator rotor critical speed of a million kilowatt class nuclear power were studied.The results showed that bearing stiffnesses by FEA were very close to experienced values.At the same time, critical speeds of TG rotor varies more sensitively with smaller bearing support stiffnesses, the bearing support stiffness should be big enough in design.

Key words: end-bracket bearing pedestal, supporting stiffness, critical speed, 1000MW nuclear powerturbine-generator