What is Metal Forming?
Metal Forming is a fabrication process that forces metal into a desired shape out of sheet metal or tubing.
In most cases the metal forming production processes allow for the mass production of components used in industrial applications such as aerospace, automotive, appliances, builders hardware, sealing technologies, sensors and bearings just to name a few.
Metal forming is achieved through a mechanical process that is referred to the principle of plastic deformation. This occurs by applying force greater than the yield strength of a material. Once the force is applied, the change in physical shape of the material cannot be reversed. Plastically deforming metal is the act of permanently bending, stretching or compressing material into another geometric shape. The degree to which the metal changes shape is proportional to the stress applied to it. For the metal workpiece to change its shape permanently it must reach its proportional limit of stress. This is achieved through the metal forming process.
Typical Metal Forming Processes
There are different types of metal forming processes utilized for mass production.
Some of the most common metal forming methods include:
- Deep drawing is a process of forming metal into complex shapes achieved by a transfer press in which each station operates independently from the others. The first operation in the press creates a flat blank which is carried through as many as 12 punch and die operations to ultimately produce a finished part.
- Roll Forming is a process of feeding finished, coiled or flat metal through a series of rollers where each roller station further manipulates the piece of metal into the final shape.
- Extrusion is a metal forming process by which long straight metal parts can be produced. Extrusion is done by squeezing metal in a closed cavity through a die using a mechanical or hydraulic press.
- Press Braking is a metal deformation process that aligns a piece of sheet or plate metal along an axis. This is achieved by using a press brake or machine pressing tool to clamp the metal piece between a punch and die set.
- Stamping involves placing flat sheet metal in either coil or blank form into a stamping press. In the press, a tool and die surface form the metal into a desired shape. Punching, blanking, bending, coining, embossing, and flanging are all stamping techniques used to shape the workpiece.
- Forging is defined as the process of heating, deforming and finishing a piece of metal. Forgings are made by forcing materials desired shapes either by the force of hammer upon an anvil or by a die press enclosing a piece of metal and squeeze forming the part.
- Casting is the process of pouring molten metal into a mold that contains an impression of desired shape. The metal then cools and hardens into the form given to it by its shaped mold.
The Deep Draw Metal Forming Process
The deep drawing process falls under the umbrella term of metal forming and metal stamping.
Deep drawn parts are produced in a transfer press and can produce high production volumes. Punches and dies are the tools used to draw and shape the raw material to produce the deep drawn component.
The raw material comes in strip coil form. The first operation at the press cuts a flat blank from the strip of metal. The blank is then carried by transfer fingers to the next operation where a cup is drawn. The cup is then transferred to the next station where the metal is drawn in a percentage allowed. There can be as many as 12 punch and die operations to arrive at the final part.
Deep Draw Stamping Techniques are mastered by an experienced eyelet toolmaker. An eyelet toolmaker must go through an apprenticeship program and complete 8,000 hours of work-based learning before becoming a Journeyman.
Here at Prospect Machine Products we have been dedicated to deep drawing metal for over 70 years.