SHEET METAL AND METAL FORMING Copyright Goodheart-Willcox Co., Inc. Chapter 17 Cold Forming Metal Sheet 279 17.2 Forming Operations Forming is a process in which flat metal blanks are g made into three-dimensional shapes using a press and die. The technique is often called drawing. A few of the g g more widely used forming techniques are draw press, Guerin process, Marform process, hydroforming, bulging, stretch forming, bending, and roll forming. 17.2.1 Draw Press Operation The draw press operation is a metal-shaping process performed on a mechanical or hydraulic draw press, Figure 17-8, using a matched metal punch and die set, Figure 17-9. The die holds the blank in place, and the matching punch is lowered to shape the metal. 17.2.2 Guerin Process The Guerin process is used to form shallow parts in rubber dies, Figure 17-10. Several thin rubber mats are mounted in a container attached to the press ram. The rubber mats compress as the ram is lowered, forcing the metal blank to assume the shape of the form block. Komatsu America Industries Figure 17-8. This servo-driven draw press is capable of a wide range of operations, including multi-hit, coining, precision forming, shallow draw, heavy blanking, and forming and piercing operations. Goodheart-Willcox Publisher Figure 17-9. The drawing process using a matched punch and die set. A—The die halves hold the metal blank while the punch is lowered into it. B—The metal blank is drawn into the final shape with the matched punch and die set. Drawn shell Die A B Drawn shell Blank holding ring Blank before drawing Punch Punch Die Goodheart-Willcox Publisher Figure 17-10. A diagram of the Guerin process. The rubber pad forms the female part of the die. Ram Platen Guide posts Platen Bolster Metal blank Rubber mats Container Form block