Fault Analysis and Control of Coking and Rubbing in Steam Turbine Shaft Seals
By monitoring and analyzing the abnormal vibration fluctuations of a certain petrochemical company's steam turbine,using vibration spectrum diagrams,axis trajectory and axis position diagrams,in association with the trend changes of relevant parameters of the unit,fault feature identification and fault mechanism analysis were conducted.The analysis indicates that the anomalous vibration of the steam turbine is attributable to the leakage of lubricating oil and gas at the shaft seal,which gives rise to the formation of coke at elevated temperatures and adherence to the oil seal position.Once a certain thickness of coke has accumulated,the protruding portion collides and rubs against the diameter of the rotor shaft.To mitigate the vibration experienced by the turbine,a series of measures were implemented,including adjustments to the nitrogen seal pressure,an increase in the cooling air volume for the shaft seal,and the addition of baffles.During the turbine shutdown,a set of preventive maintenance procedures were put forth to prevent potential equipment failure.
万方数据
维普
