Evaluation of the Improved Envelope Spectrum via Feature Optimization-gram (IESFOgram) for bearing diagnostics under low rotating speeds

摘要

one of the crucial parts in the rotating equipment are rolling element bearings in which the faults can lead to machine breakdown and product loss. Nowadays, many approaches have been proposed for the detection of bearing faults operating at medium to high rotating speeds. On the other hand, state of the art methods often fail to detect bearing faults under low speeds due to several obstacles. Therefore early, robust and accurate bearing diagnostics under low-speed conditions is still a challenge. In this paper the effectiveness of the IESFOgram for bearing diagnostics under slow-speed conditions is investigated and compared with the well-known Kurtogram. The approach is implemented on vibration data, taken from a test rig operating under low-speed during an Accelerated Life Test (ALT). Interestingly due to the character of the ALTs more than one types of faults occur. Various Features, targeted and blind, are tested in the IESFOgram. The method is evaluated at different stages of the occurring faults and it can be concluded that IESFOgram can accurately diagnose the worn-out bearing operating under low-speed conditions.