Method for producing forged crankshaft

A method for producing a forged crankshaft including journals serving as a center of rotation, pins decentered from the journals, and crank arms connecting the journals and the pins, wherein

• the forged crankshaft further includes counterweights integrated with all or some of the crank arms,
• the method comprising:
• a die forging step of obtaining a forged blank with flash having a crankshaft shape;
• and
• a trimming step of removing the flash from the forged blank while nipping the forged blank with a pair of holding dies, wherein:
• the forged blank includes rough journals, rough pins, rough crank arms, and rough counterweights, which correspond to the journals, the pins, the crank arms, and the counterweights of the forged crankshaft, respectively;
• at least one of the rough crank arms has, in a region near an adjacent one of the rough pins, a first excess portion protruding from an outer periphery of a side portion of the rough crank arm;
• and
• when the forged blank is nipped with the pair of holding dies in the trimming step, the first excess portion is deformed by the pair of holding dies to bulge toward an adjacent one of the rough journals.