Abstract:

The 350MW heating unit with separated high and medium pressure subcylinder which is made by Harbin Steam Turbine Factory Company Limited takes a new steam sealing to improve cylinder efficiency. But it also brings certain problems to the start and operation of the steam turbine. During commissioning period of the unit, there were large bearing vibration, water contained in lowpressure shaft seal, serious steam leakage of highpressure cylinder at shaft end and other faults. Through the onsite troubleshooting, measures such as increasing the rotation rate set point of units warming , optimizing the valve flow control, reinforcing the vibration measuring bracket, eliminating the cylinder expansion resistance, and correcting the highspeed dynamic balance of rotor were taken. After the treatment, the main faults in the generating units are eliminated, which ensures the 168hour successful trial of the retrofit unit with full load.

Key words:

steam turbine generator, bearing vibration；dynamic balance；shaft seal