Taking a million kilowatt nuclear power half speed steam turbine generator set as the research object

a dynamic model of spring foundation bearing rotor is established by using the rotor dynamics professional analysis software ARMD. The dynamic characteristics of the shafting are obtained through dynamic calculation and analysis.The accuracy of the calculation model is verified by the coincidence of the field measured critical speed of the shafting and the calculated value. On this basis

the vibration response caused by the thermal imbalance of the seal pad of the generator is calculated. It is found that the vibration changes are mainly concentrated at the rotor of the generator

and the thermal imbalance of the seal pad is only the direct influence factor of the vibration fluctuation of the shaft system

but not the root cause. At the same time

the oil film stress of the seal pad under different operating conditions is analyzed

and it is found that the axial inclination has the greatest impact on the stress of the seal pad. Therefore

the processing and installation process shall be ensured during the maintenance and adjustment of the unit to prevent the shaft system deflection during the operation of the seal pad.