Abstract: The joint coupling and system interference of the traditional welding robot are common in complex intersecting line welding and all position welding, resulting in obvious welding limitation. To overcome the system interference generated by the position adjustment of welding torch, a new type of welding torch which can adjust the working angle is designed on the basis of the dynamic variation of the welding angle and depth at different positions. The torch presents a certain real-time adjustment capability. In the process of automatic welding, the all position welding can be completed by adjusting the working angle of the welding torch with the robot, to enhance the practicability and feasibility of the robot and meet the welding request with complex intersection curve. The kinematics model and welding process of welding torch were simulated by OpenGL. The simulation results prove the validity of the designed automatic welding torch.