Abstract: A novel laser stitch welding system is introduced. It can weld together two superposed stainless steel plates of different thickness and within the size range of 12.0 m×1.5 m. In order to solve the problem of easy deformation of large-size stainless steel plates, a major-minor clamping mechanism is proposed, which can effectively control the deformation of large-size plates in the welding process and eliminate the gap between the plates. The ufxyz-type four-axis linkage scheme is designed. The u axis and the x axis are in the same direction. The u axis drives the plate to move in a large scope. The x axis drives the laser head to move in a small scope. The composite motion of u axis and x axis improves the precision and dynamic response speed of the system. The experimental results show that the steel plates welded by this system can withstand pressure up to 6.1 MPa.

Key words: Finite element analysis, Multi-body system, Error modeling, Laser stitch welding