Deep drawing is a sheet metal manufacturing process. This operation transform a flat sheet blank into a three dimensional part. Usually the depth of the drawn part exceeds its diameter it is the reason why this process is called “deep”.
The way to carry out a deep drawing process is with a punch and a die. The punch has the desired shape of the base of the part. The die cavity matches the punch and is a little wider to allow for its passage, as well as clearance. Clearance must be enough to avoid cut the sheet and allow the material flow. Sheet metal piece, called blank, is hold over the die opening by pressure apply by a blank holder. The punch travels towards the blank. The punch forces the sheet metal into the die cavity, forming desired shape. Parts manufactured by deep drawing cannot be complex shapes, being necessary do the process in several phases for complex parts. Hydraulic or mechanical presses are necessary to carry out this industrial process. Hydraulic presses can control blank holder and punch separately but the mechanical presses are usually faster.

MATERIALS AND PRODUCTS

For this process, material must be ductile and malleable with a low yield stress and enough plasticity to obtain the desired part without fractures. For this reasons more suitable materials are:

• Mild steel
• Austenitic stainless steel
• Low alloy aluminum and copper
• Brass

Deep drawing is specially used by automotive industry and for recipes manufacture as could be: crankcase, gas tanks, mudguards, suspension arms, container lids, cups, bowls, containers, tanks, fire extinguishers, back cover for spotlights, kitchenware, bearings…