Abstract: Abstract:Some problems, such as sluggish and jam, occurred in the steam turbine governing system. The problems were analyzed, and it was confirmed that there were defects in the front bearing seat angular pin (plate) and the oil return pipe. In unit startup process, the defects can lead the front bearing seat to shift to left front direction, which will cause the rotor to be offcenter, the steam leakage in front steam seal right side to increase, and the heating expansion of the lever and support of the governing valve to be uneven. The sliding key system was adjusted, the equipment hidden danger was eliminated, and the normal operation of the unit was ensured.

Key words: Keywords:steam turbine, governing system, angular pin, oil return pipe, bearing seat, steam seal