Method of producing forged part and method of producing suspension arm for automotive vehicles

A method of producing an automotive suspension arm, comprising:

• holding an outer periphery of a bar-shaped material between split clamp jigs;
• upsetting the material, held by the clamp jigs, to a first predetermined shape with a pair of upsetting dies disposed on both axial ends of the material by pressing the upsetting dies on the material and forming a burr on the outer periphery of the material in a clearance (S) defined between the clamp jigs during the upsetting operation, wherein the upsetting operation produces large-diameter portions at respective axial ends of the material;
• bending the upset material with a bending die assembly;
• forging the bent material into a second predetermined shape with split forging dies after bending, wherein a burr is formed on the outer periphery of the material during the forging operation;
• finish-machining the forged material to remove the burr generated on the outer periphery of the material after forging;
• and
• drilling bush-mounting holes in the large-diameter portions of the axial ends of the finish-machined material,
• wherein, when forging, a direction in which the material is forged is set to a forging direction such that a position of the burr formed during the forging operation is the same as a position of the burr formed during the upsetting operation.

A method of producing a forged automotive part, comprising:

• upsetting a material with upsetting dies, wherein the material is held between split jigs during the upsetting operation, wherein a burr is formed on an outer periphery of the material in a clearance formed between the jigs during the upsetting operation,
• forging the upset material with split forging dies after the upsetting operation, wherein a burr is formed on the outer periphery of the material during the forging operation, and
• removing the burr formed during the upsetting and forging operations,
• wherein the forging operation is performed so that the burr formed during the forging operation is formed in the same position as the burr formed during the upsetting operation.