Aiming at the failure of the regeneration fan of a petrochemical aromatics complex unit,data analysis and classification investigation are carried out from the aspects of rapid changesin fan vibration,bearing failure and so on.Professional monitoring and testing techniques in both dynamic and static fieldsare utilized comprehensively to analyze and describe the occurrence and development process of bearing failure.Ultimately,it is determined that the abnormal shutdown of the fan is caused by issues concerning the installation quality of the bearing and the material of the retaining frame.This case indicates that ensuring compliant bearing installation methods and installation quality,as well as selecting the retaining frame material that meets the plasticity and toughness requirements,can effectively prevent fan bearing failures.This can provide reference for preventive maintenance and installation inspections of the equipment.