Variation Simulation of Spot Welding Sequence for Sheet Metal Assemblies

Paper in proceedings, 2010

One of many factors affecting the final geometrical outcome of a sheet metal assembly is the spot welding sequence, used when the parts are welded together. It is of course desirable to choose a welding sequence that minimizes both variation and deviation in critical dimensions of the final assembly. In this paper, the correlation between offset and standard deviation for different welding sequences is investigated. It turns out that in most cases, those two quantities are correlated, which of course facilitate the search of an optimal welding sequence. A method for including the welding sequence in variation simulation is also presented, as well as an investigation of the number of welding points needed to lock the geometry, i.e. the number of geometry points needed. The investigations are based on industrial case studies.