The bearing vibration of No.2, No.3, No.4, No.5, No.6 of a 600 MW supercritical steam turbine in a power plant is relatively large. In order to solve this problem, the intake mode of the steam turbine was changed by prolonging the operation time of the mixing valve with the initial load to make the steam turbine expand sufficiently, which improved the differential expansion of the high pressure cylinder, and the bearing load was also changed to reduce the bearing vibration, then the steam turbine vibration can reach the optimal state.
