Hollow forging

(1) Processes for forgingThe process of working metal to a desired shape by impact or pressure in hammers, forging machines (upsetters), presses, rolls, and related forming equipment. tubes or ring forgings. (2) Cylindrical open die forgingForging worked between flat or simple contour dies by repeated strokes and manipulation of the workpiece. Also known as "hand" or "smith" forging. See Open-Die Forging., e.g., thick-walled tubes or rings.