A MANUFACTURING METHOD OF PROJECTING PARTS OF STRAPS

摘要

According to the present invention, a forming method for a strap supporting protrusion includes: a supporting protrusion base material preparation step for forming a pair of holes at a position on a plate material to be formed with a supporting protrusion to prepare a supporting protrusion base material in a strap shape between the holes; a first forming step for pressurizing the supporting protrusion base material between the holes to form a first protrusion surface protruding upwardly in the longitudinal direction of the strap shape; a second forming step for forming a first curved portion dented downwardly on the uppermost central part of the first protrusion surface formed in the first forming step, in the width direction of the strap shape; and a third forming step for forming a second curved portion having dent curvature corresponding to the curvature of a fuel rod by re-pressurizing the first curved portion formed in the second forming step.