Marking structure producing method for socket wrench insert used for screwing and unscrewing bolts and screw nuts, involves polishing printed layer provided around marking, and galvanizing inner and outer surfaces of insert except layer

摘要

The method involves producing a mold of a socket wrench insert by a spinning process or forging process. A concave marking e.g. size of insert, is formed at a preset point on an outer surface of the insert by a milling process. The insert is subjected to a heat treatment. An insulating printing layer is printed on the outer surface corresponding to the marking by applying colors. The printed layer provided around the marking is polished. An inner surface and the outer surface of the insert except the printing layer are galvanized. An independent claim is also included for a marking structure of a socket wrench insert.