Vehicle tool for complex welding part

The invention discloses a vehicle tool for a complex welding part. A supporting assembly used for supporting the complex welding part, pressing assemblies used for pressing the complex welding part and a counterweight assembly are arranged on the front face of a transition disc; the supporting assembly comprises a main supporting part corresponding to the flange plate edge of the complex welding part and an auxiliary movable supporting part corresponding to the thin cylindrical section of the complex welding part, the main supporting part is provided with a large positioning groove matched with the flange plate edge, and the auxiliary movable supporting part is provided with a small positioning groove corresponding to the thin cylindrical section; and the pressing assemblies comprise the first pressing assembly used for pressing a reinforcing rib and the second pressing assembly used for pressing an auxiliary cylindrical section. Through the cooperation of all the components of the vehicle tool, and the compl