A parametric study of sheet metal joints for dimensional integrity

The characteristics of joints between parts are one of the most critical issues in variation simulation analysis. This paper presents a parametric study of the dimensional variation characteristics of butt joints and slip joints. These two basic joints encompass the whole domain of joints used in sheet metal assemblies for structural extension. A geometrical model was proposed for predicting the assembly variation in order to take into consideration the possibility of part deformation and tool variation. Butt joints act like rigid bodies in the normal direction. For slip joints, the sensitivity coefficient in the slip direction is a function of tooling variations. The variation from individual part and tooling can be eliminated or substantially reduced if the product structure and assembly process is properly designed. A simple four-part assembly example shows the structure and assembly process. This result provides improved understanding of sheet metal assembly processes and provides a new idea for adaptive product and process design.