Reliability Analysis On The Power Wheel-SET Of Crh5Type Emu

Reliability analysis is carried out for the powered wheelset of CRH5type EMU. Following research studies are performed in the present thesis:1. An integrated model is constructed for the stress calculation of wheelset, in which the affecting on the distributed wheelset stresses are taken into account of multi-interference fits and wheel-track contact.2. Design mechanical strength reliability is assessed on the wheel and axle. Stresses of the wheelset are calculated using the possible critical mechanical loads for the wheel coded by AAR S660. A probabilistic assessment is made by the normal distributed critical mechanical strength and stresses. Results reveal that, in terms of von Mises stress, the weakest position for the axle is at the inner side of wheelset. But the reliability level is still greater than0.9999at a confidence of97.5%. For the wheel, the weakest position is at the transition position between the web and gub of wheel. Fortunately, the reliability level is also greater than0.9999at a confidence of97.5%.3. Design fatigue strength reliability is assessed on the wheel and axle. The fatigue stresses are calculated using the loads of three operation cases for the wheel coded by EN13979-1. A probabilistic durability assessment is then performed for the wheel and axle. Results reveal that,1) In terms of von Mises stress amplitude, the critical operational case is at the curved line running. The weakest position of the axle is at the inner side of wheel seat. Fortunately, the reliability level is also greater than0.9999at a confidence of97.5%.2) In terms of either radial stress amplitude or principal stress amplitude, the critical operational case is at the line switch piece running. The weakest position of the wheel is at the transition position of wheel web inner side. Fortunately, the reliability levels are all greater than0.9999at a confidence of97.5%.4. Reliability analysis method is explored on the spectral loading mode of wheelset. On a basis of practical line spectral loading piece for the wheelset, the corresponding spectral stressing piece is obtained using the squares polynormal formulation regressing method by the tressing data from2n+1times of the integrated finite calculation of wheelset. Then reliability assessment and life prediction are effectively performed using a reliability analysis method including super-long life regime. What a most valuable noted result is that,2mm deepth weakest sub-tread layer is revealed for the wheel rim. Possible lives for the wheel tread spalling are only around248.7km at the confidence-reliability set of90%-0.9,107.4km at95%-0.975, and36.5km at97.5%-0.999.The present research has provided a valuable guide for the wheelset improving design and service management. And the research work is supported by the Natural Science Foundation of China (U1334204,51175439), Key Projects of Science and Technology Research and Development Program of Railway (2009J015,2013J008-C), and Open Research Program of State Key Laboratory of Traction Power (2012TPL-T02).