Objective AIBs (axlebox-integrated bogies) feature high equipment space utilization and superior performance. To match such bogies and meet the lightweight development requirements of urban rail transit vehicles, it is necessary to design a novel traction-bolster buffer structure for A-type aluminum alloy platform carbodies.

Method First, based on the interface elements of the AIBs (including center pivot seat, side bearer and hanger bracket), innovate structural designs are carried out for core components such as the bolster and traction beam. Aluminum alloy profile assembly welding and integral machining processes are adopted to ensure precision, and stainless-steel wear plates are additionally installed. Second, structural light-weighting is achieved through optimization measures (such as reducing wall thickness and opening weight-reduction holes). Finally, in accordance with international standards such as EN 12663-1:2010, a whole-vehicle finite element model incorporating the traction-bolster buffer structure is established, systematic simulation analysis and evaluation of static strength (including 25 working conditions) and fatigue strength (including 4 working conditions) are conducted.

Result & Conclusion  Compared with conventional designs, the proposed traction-bolster buffer structure reduces manufacturing procedures by approximately 30% and vehicle weight by about 40%, demonstrating significant light-weighting effects. Simulation results show that the maximum stress under the most unfavorable loading condition is 154 MPa, and the maximum cumulative fatigue damage is 0.916, both satisfying the standard requirements. In addition, the static strength test data show good agreement with the simulation results.