Non shaft screw manufacturing method and non shaft screw thereby

摘要

The present invention relates to a screw and, more specifically, to a technology related to a method to manufacture a non-shaft screw with various lengths in accordance with user′s requirements and a non-shaft screw thereby. According to the present invention, the method to manufacture a non-shaft screw comprises: a unit non-shaft screw making step of forming a unit non-shaft screw not having a central shaft; a temporary shaft connection step of inserting a temporary shaft along the central line of the unit non-shaft screw to perform partial temporary welding; an outer surface processing step of processing the outer surface of the unit non-shaft screw while fixing both ends of the temporary shaft connected to the unit non-shaft screw to cutting equipment to rotate the unit non-shaft screw; a non-shaft screw module making step of inserting a plurality of unit non-shaft screws into one auxiliary shaft to weld and connect an end part of the adjacent unit non-shaft screws; and an adaptor coupling step of connecting an adaptor to transfer rotational force through one end of the unit non-shaft screw module from which the auxiliary shaft is removed.