Abstract: To provide the manufacturing method for the press work product reducing the chance of causing distortion of the countersink as press-forming the countersink. This is the manufacturing method for a press work product which has a tapped bore for a stem of a flat countersink head screw to penetrate therethrough and a countersink formed around a circumferential line of the tapped bore for a head of the flat countersink head screw to seat therein, comprising steps of forming a work as the press work product by punching a plate material, trimming an outside diameter of said work, and forming said countersink by inserting said work after trimming the outside diameter into a press die to press form thereof.

Abstract: A rolled steel plate as a raw material is press-formed into a pressed work provided with a boss section, and the work is fitted to a shaft by press-fitting of the shaft into the boss section. Rolling flow of internal metallographic layers in the boss section is curved like a letter S. Moreover, a manufacturing method of such a pressed work comprises: a primary-boss forming process during which a primary boss having a hole section and a protruding section protruding from the periphery of the hole section at a position corresponding to the boss section on a plane-like raw material is formed; and a boss-section forming process during which the protruding section is pressed and deformed in the protruding length direction to form the boss section.