A fault feature extraction method for rotor rubbing based on load identification and measured impact response

Rotor rubbing is a common fault of rotating machinery, and usually induced by other faults, such as bending, clearance, unbalance and so on. The essential characteristic of this fault is the impact and friction between rotor and stator, so this paper puts forward a method for representing the rubbing fault by identifying the suffered dynamic load of rotor and stator. The basic formula of load identification is built, and the measured impact response is used to replace the system real impulse response function. The experiment results show that the proposed method can effectively extract the impact components of rotor and stator, and detecting stator vibration signal is more effective to represent rubbing fault than that of rotor, and the analysis result has clear credibility. Meanwhile, the proposed method is convenient for practical engineering application.