The modeling and analysis of a butting assembly in the presence of workpiece surface roughness and part dimensional error

Butt joints are frequently used in assembly processes. However, relatively little attention has been paid to the proper design and selection of butt joint geometries and processes. In this paper, the assembly accuracy performance of different butt joint geometries and joining processes has been studied by using analytical models for part misalignment in the presence of part dimensional errors, surface roughness, and surface waviness. Our analysis shows that both short-term roughness, as well as long-term waviness, has an effect on the assembly precision levels. The analysis is verified statistically using a simulation program; experiments are conducted using this program to show that the differences in the performance between different butt joining methods can be significant. Therefore, proper design and selection of forming butting assemblies can have important impacts on the assembly precision.