An Introduction to the Deep Drawn Metal Stamping Process

Metal stamping processes are one of the most common methods used to shape sheet metal of many different materials into desired shapes. When the depth of the stamped part is equal to or greater than the maximum diameter of the part, it is considered deep drawn.

The deep draw process begins by feeding the desired metal or alloy into the machine either in a continuous strip or by individual sheet. The initial stage cuts out a circular blank to be used in the stamping process.

The resulting blank is transferred to the next station where it is forced into a die cavity by a specifically designed punch. An area of the die called the pressure pad applies just enough force to direct the flow of material as it is drawn into the die. This reduces the radial stresses to the material and prevents the metal from wrinkling.

Typical deep drawn metal stamping presses are multi-station, with each station changing the geometry of the part sequentially until the final design is achieved. Using this method, even very complex geometries can be created from a single blank.

Once the general shape of the part has been formed, a process known as piercing creates any slots or openings that may be required in the finished product. The final step is the trimming process, where any excess material is removed from the finished part.

Forces introduced into the material during the process alter the grain pattern of the material, resulting in a finished part that is typically stronger than the original material. In situations where the ductility of the finished part is desirable, the deep drawn part can be further conditioned using a process called annealing. This process reduces the stresses introduced to the material during the draw process and restores the material to its original state.

Given the nature of the process design, finished parts typically display tight tolerances, high quality surface finish, and high strength.  The deep drawn metal stamping process is used in many industries around the globe including automotive, medical, and military ordnance.