Aiming at the problem of plain bearing acoustic emission (AE) signal interference seriously

fault signal separation difficulty

friction fault monitoring difficulty

based on the pulse characteristic of impact signal

a method based on shock signals to monitor plain bearing faults was proposed

which established the relation between impulse signal and bearing friction fault. Firstly

the Kmeans singlular value decomposition (KSVD) dictionary was used to capture impact characteristics

and the time of impact pulse generation was determined. In order to sharpen and enhance impact signal

the impact envelope signal was demodulated by the Hilbert envelope. Secondly

the bell pulse parameter was introduced to fit the single impact envelope signal

and the simplified formula of the strength of the impact envelope signal was further deduced

which was applied to the contact friction fault identification of the plain bearing. Finally

the friction fault of plain bearing was simulated by cutting off oil supply channels. Comparing with the traditional characteristics of AE

the proposed algorithm were easier to identify early friction fault and higher computational efficiency and can completly describe bearing friction process. So

the proposed algorithm provides a new way for the plain bearing contact friction fault diagnosis.