A Methodology for Assessing the Influence of Spot Welds on a Vehicle Body Node Using the Finite Elements Method and a DOE Analysis

The body structure of a vehicle is constantly under different load cases, and the spot-welded joints are usually the weakest parts, being normally oversized by the designers. This paper drives a study about the optimal number and location of the welding spots in order to improve the durability and performance of a vehicle body node, related to a specific load case. In addition, the manufacturing time and costs reduction are consequences of this optimization. Computational tools are used and a DOE (Design of Experiments) is performed to characterize the problem statistically, through a location changing sensibility analysis. A Finite Elements software was used for analyzing the stress distribution for each case. Therefore, the feasible designs will be chosen considering the best relation between performance and number of welding spots.