Objective The underframe skirt panels of suburban railway trains are arranged on the side of the equipment beneath the vehicle, which can optimize the aerodynamic performance of the underframe area, reduce air resistance, and provide convenience for the routine inspection and maintenance. The structural strength of the skirt panels must meet the various loads encountered during vehicle operation. Therefore, it is necessary to study the structural characteristics of the underframe skirt panels and their influencing factors, in order to provide a basis for decision-making regarding the technical scheme of the underframe skirt panels and vehicle design.

Method According to different equipment inspection requirements, the underframe skirt panels can be divided into fixed and movable ones. The movable skirt panels need to be opened and closed frequently during operation, therefore is analyzed as the focus. Starting from three main components—the skirt panel profile, skirt lock, and support rod—their functions, installation forms, and structural characteristics are analyzed. Combined with requirements regarding the convenience of inspection and maintenance, train weight control, and aerodynamics, further research on the structure of the underframe skirt panels is conducted.

Result & Conclusion  When determining the structure of the underframe skirt, multiple factors such as maintenance requirements, operating conditions, cost control, and drag reduction should be comprehensively considered, while adhering to relevant standards and specifications, so as to achieve a balance between structural optimization and functional performance. The consideration pathway derived from the research and analysis is as follows: first, consider equipment inspection requirements to determine the arrangement method and skirt length of the underframe skirt panels; second, consider vehicle operational loads to determine the cross-sectional dimensions of the panel and the form of the connection structure; finally, consider the aerodynamic performance of the whole vehicle to determine the aerodynamic drag index of the entire train.