Forming tool

The utility model discloses a forming tool, and belongs to the technical field of preforming processes. The forming tool is used for extruding a plane hole of a part to be preformed into a flanging hole, the forming tool comprises a forming insert, a forming die and a lower pressing die, and a flanging groove is concavely formed in the first end face of the forming insert in the thickness direction; the forming insert is detachably embedded in the mounting groove, and the first end face of the forming insert is flush with the upper end face of the forming die; a flanging boss is arranged on the end face, close to the forming insert, of the lower pressing die in the thickness direction in a protruding mode, and the flanging boss is matched with the flanging groove. And the to-be-preformed part is configured to be clamped between the forming die and the lower pressing die. According to actual machining requirements, forming inserts of different models can be replaced on the forming die, flanging holes of differ