This paper presents a parallel-serial machine tool designed for welding joint trajectory in XY directions. The design features of this machine tool are briefly addressed based on the requirements of FSW process. By analyzing the characteristics of the parallel kinematic part of the hybrid machine tool, a simple and effective method on avoiding collisions between the spindle and the frame of moving platform has been presented. A strategy for applying a continuous welding process on tool paths which are composed of a set of linear segments has been discussed. From the design we demonstrate the advantages of applying hybrid machine tool in two dimensional FSW.