Abstract: In the petrochemical industry, the flue gas turbine is the core energy recovery equipment for catalytic cracking units. However, the complex composition of flue gas exposes its rotor system to harsh operating conditions such as high temperature, high pressure and erosion for a long time, leading to frequent rotor imbalance faults, which seriously affect the safe and stable operation of catalytic units. Aiming at the issue of complex operating conditions of flue gas turbines and difficulty in obtaining effective monitoring data, this paper took the flue gas turbine rotor system as the research object. It constructed a multi-parameter coupling diagnosis model based on fault traceability and realized the multi-physics simulation of the operating conditions of flue gas turbines and clarified the dynamic response characteristics of the rotor system. To address the persistent industry challenges of "difficult fault traceability and quantification in imbalance diagnosis," this study developed a novel methodology for rotor imbalance identification based on fault traceability and a non-stop quantitative analysis technology. By establishing a fault signature database through integration of simulation models and on-site measured data, and leveraging Pearson correlation analysis to extract on-site signal features and compute similarity index, the proposed framework enables precise root-cause localization and quantitative assessment of faults.

Key words: flue gas turbinelfault diagnosislrotor imbalancelfault traceabilitylmulti-parameter couplinglcorrelation analysis