Base Vibration Response Characteristicanalysis Of Fault Rolling Bearing In Rotor System

Rolling bearing is the most widely used mechanical part in rotor system of rotating machinery, and one of the most easily damaged parts. It is very important to diagnose and predict the rotating machinery rolling bearing fault on operation safely and effectively, changing maintenance system and so on.In traditional fault diagnosis method of rotating machinery rolling bearing, sensors are installed on bearing seats near to the vibration source, but the sensor is very difficult to be installed and has poor universlity. Because of the vibration transfer characteristic, the fault vibration signals will be transfered to the base. Installing the sensor on the base is very convenient and has universality. In this paper, base vibration response characteristics of fault rolling bearing in rotor system are researched. It provides a theoretical basis for rotating machinery rolling bearing fault diagnosis which install the sensor on the base.In this paper, vibration mechanism, finite element analysis and perimental analysis are studied, the vibration response of rolling bearing on base are researched. The main research work is:1.The fault mechanism of rolling bearing is analyzed from theory. The basic structure, vibration mechanism and main failure forms of rolling bearing are discussed, the vibration signals characteristic frequency of three typical rolling bearing faults is researched, which are inner race fault, outer race fault and ball fault.2.The finite element analysis of rotor-rolling bearing-base system is studied. The comprehensive fault simulation testbed of Spectra Quest is taken as an object, the rotor-rolling bearing-base system is constructed, the natural frequency and mode of rotational parts and whole system are solved by analyzing them through finite element analysis software ANSYS; the ideal installation position of sensor is obtained from harmonic response analysis which is based on the result of rotor-rolling bearing-base system modal analysis.3.The base vibration responses of fault rolling bearing vibration characteristics are studied by experiments. Rolling bearing vibration testing experiments with different rolling bearing fault type, rotational speed and load are carried out on comprehensive fault simulation testbed, the base vibration responses to fault rolling bearing are researched from frequency features and time-domain statistics,the base frequency responses of fault rolling bearing in different working condition are studied, the vibration characteristics of rotor-rolling bearing-base are analyzed by experiments.In this paper, the vibration responses of rolling bearing fault signal on the base are researched through vibration analysis on rotor-rolling bearing-base system, which prepares for effective condition monitoring and fault diagnosis of rolling bearing on base.