Compliant Variation Analysis for High-Speed Train With Consideration of Welding Distortion

An important goal of the manufacturing process is to achieve high accuracy and reliability of products. For modern equipment manufacturing industries, such as high-speed trains (HST), the assembly performance is guaranteed by the product design and manufacturing technique. Since dimensional control is much related to manufacturing quality, assembly variation analysis methods play an increasingly crucial role in advanced manufacturing industry. Nevertheless, the relationship between welding distortions and tolerance design has not been considered in most existing assembly variation analysis models, which lack of quantitative analysis between precision and performance. In this study, a compliant variation analysis methodology considering both static structural deformation and welding distortion is developed and applied to predict assembly variation of the roof of HST. Firstly, welding simulation is carried out to predict welding shrinkage and angular distortion with different welding configurations. Then, welding distortion is equivalent to dimensional variation and considered in the compliant variation analysis model with offset tolerance technique. Finally, a compliant variation simulation is carried out to investigate the variation propagation influence of welding shrinkage and distortion on the final dimension of assembly. The presented methodology provides an efficient tool for variation analysis of HST, also offers a theoretical basis and experimental support for mechanical properties of compliant assembly.