Method and system for forming protrusions, and method for manufacturing metal component having protrusions

A system for forming one or more protrusions on one surface of a metal workpiece, the system comprising:

• a support die configured to support a metal workpiece;
• a pressure die configured to suppress a lifting of the metal workpiece;
• wherein one or more through-holes are formed in at least one of the support die and the pressure die, the through-holes being configured to serve as female molds for forming the protrusions on one surface of the metal workpiece;
• a clamping device configured to clamp the support die and the pressure die;
• a pressing die or a pressing jig configured to press end cross sections of two or more outer peripheral end parts of the metal workpiece at two or more different positions from two or more directions toward the to be formed protrusions on one surface of the metal workpiece,
• wherein the two more directions are perpendicular or oblique to an upright direction of the protrusion, and the pressing die or the pressing jig is a separate individually movable component from the support die and the pressure die,
• wherein said outer peripheral end parts are positioned in point symmetry on sides of the metal workpiece when a center of a bottom surface of the one or more to be formed protrusions is a symmetrical center;
• and
• a press molding machine equipped with the pressing die or the pressing jig and configured to drive the pressing of the end cross sections of the two or more outer peripheral end parts of the metal workpiece at said two or more different positions by press molding using the pressing die or the pressing jig,
• wherein the system has no heating device configured to heat the metal workpiece so that the pressing is performed at a temperature lower than a softening point of the metal used as the metal workpiece without heating the metal workpiece.