A Hybrid Method for Detection and Diagnosis of Faulty Roller Bearings

There are few research on bearing fault detection and diagnosis which combine constant speed with variable speed. In this paper, a hybrid method is proposed to realize the nondestructive testing and fault diagnosis of roller bearing faults. First, adopts computed order tracking (COT) and variational mode decomposition (VMD) based order spectrum method to detect bearing faults under variable speed condition. Then, by using the method of VMD-based envelope spectrum analysis, we analyze a certain speed signal which is consistent with the velocity in the condition of variable speed, and verify the analysis under the condition of variable speed. The experimental results show that the method can realize the effective diagnosis of the fault bearing.