Method for producing a forged crankshaft

A method for producing a forged crankshaft, the crankshaft including:

• journals that define a center of rotation;
• crank pins that are eccentric with respect to the journals;
• and crank arms, each of the crank arms connecting a corresponding one of the journals to a corresponding one of the crank pins,
• the method comprising:
• a die forging step, including forming a finish forged blank with flash, the finish forged blank including a shape of the crankshaft, wherein the crank arm has an excess projecting portion at an outer periphery of each of side portions near the crank pin, the excess projecting portion projecting from the outer periphery;
• a trimming step, including removing the flash from the finish forged blank formed in the die forging step;
• and
• an excess projecting portion bending step, including inserting a first die having a U-shape to the crankshaft from a direction of eccentricity of the crank pin and bending the excess projecting portion of the crank arm toward a surface of the crank arm, the surface being adjacent to the journal, the crankshaft being obtained by removing the flash in the trimming step.