Completar frases Introduction to metal forming processesVersión en línea Explore the principles of deformation processes, incluiding: rolling, forging, extrusion and drawing por Sergio Blanco 1 A operation is one in which the shape of a metal sample is altered by deformation . Forming processes include stamping , rolling , extrusion and forging . Forming can be divided into two categories : hot and cold working . Deformation energy requirements for working are less than that of working . In a operation , a single piece of metal , normally hot , is deformed mechanically by the application of successive blows or by continuous squeezing . Rolling is the most widely used deformation process . It consists of passing metal between two rollers , which exert compressive stresses , reducing the metal thickness . is the pulling of a metal piece through a die by means of a tensile force applied to the exit side . A reduction in cross - sectional area results , with a corresponding increase in length . Metals can be formed to much closer dimensions by than by . For drawing , the starting sheet of metal is larger than the area of the punch . A pressure plate , fixed to the machine , prevents wrinkling of the edges as the plug is drawn into a top die cavity . The outer parts of the sheet are drawn in towards the die as the operation proceeds . In , a bar or metal is forced from an enclosed cavity via a die orifice by a compressive force applied by a ram .