The Study Of Fault Feature And Diagnostic Method Of Rolling Bearing In The Unstable Operation Process

Rotary machine is not working at the rotate speed condition, for example, convertertilting and rolling mill transmission mechanism. At this time the traditional fault diagnosismethods are not practical and not effective to diagnose. If we can analyse these informationwhich is in the lifting-speed condition, it’s of unique value for fault diagnosis of rotatingmachinery. Rolling bearing is one of the most important parts of rotating machinery,therefore, it is of great significance for effective fault diagnosis of rolling bearing undervariable speed. In the lifting-speed condition of rotary machine, the original signal willshow the non-steady characteristics. if using the traditional spectrum analysis, the resultswill appear serious phenomenon of "frequency smear" which is difficult to extract the faultinformation. Computed order tracking technology is an effective solution to this problem.the original time-domain signal which is sampled in ascending period should be convertedto angular-domain signal, realize the time-domain nonstationary signal transformation tothe stationary signal angle domain. researching contents are followed:First of all, this paper analyzes the fault type of rolling bearing, mechanism andcharacteristics of vibration frequency.Secondly, through the simulation signal examples illustrate "frequency smear"phenomenon in the process of speeding up signals, and the apply computational ordertracking theory to solve this problem.Finally, this paper use the computed order tracking theory combines with othermethods, for studying the fault signals of rolling bearing. Through the two aspects ofsimulated signals and experimental case study of the proposed theory.In this paper, based on the vibration signal testing, mainly use the computed ordertracking theory combining with EEMD method, The wavelet packet method, energy orderspectrum and envelope order spectrum for studying the fault signals of rolling bearingtransmission process, a series of comparison and analysis of experimental results, show theefficiency of the method proposed in this paper, and then to diagnose the failure problem inrolling bearing transmission process...