Large-cylinder-diameter forged steel piston and manufacturing method thereof

The invention discloses a large-cylinder-diameter forged steel piston and a manufacturing method thereof. The forged piston comprises a forged steel piston top and a forged steel piston skirt, the forged steel piston top and the forged steel piston skirt are connected through inertia friction welding, a first lubricating oil groove structure and a second lubricating oil groove structure are arranged in a piston skirt pin hole, and the length arrangement directions of the first lubricating oil groove structure and the second lubricating oil groove structure are perpendicular to each other on different planes. The forged steel piston top and the forged steel piston skirt are connected through inertia friction welding, and the connecting mode can meet the application requirement of a high-strength diesel engine; and the number of characteristic parts, connected through counter bores and bolts, of a traditional forged steel piston skirt is reduced, so that the size and weight of the piston are reduced. 本发明公开一种大缸径