April 26, 2010- Extruded profilesare majorly in demand. As the industries using extrusion profiles are growing , so are their needs for extruded profiles. With each passing day, there is a new need arising, which need to be matched by these extruded profiles. Industries like the automotives and house building and construction industry regularly demand complicated shapes and designs, high strength, neat looks and smooth finishes in extruded profiles.

To meet these ever increasing demands, the extruded profiles need to be bended at various spots to form the complex profile shapes. Simple extrusion is fit for producing straight extrusion profile shapes, but an additional step is required in the extrusion process to successfully extrude other shapes. Expensive tools and extrusion equipment are required to produce bended extruded profile shapes involving hollow cross sections and flanges. A set of bending dies are separately required for each cross section bended extruded profile production.

All production and quality based shortcomings of the conventional processes can be curbed by using a warm bending process. The bending and the extrusion process can also be combined into one process by bending the profile during extrusion process only, when the temperatures are still high and provide easy bending of extruded profiles.

The warm bending process consists of two main processes:

• Forming the bending radius by the outflow velocity difference.
• Forming the bending radius by the deformation work.

In the first bending process, the material flow is influenced during the extrusion process. There are three process variations used for achieving this influence.

• One, influencing the material flow with the use of a forming pocket, in the deformation zone.
• Two, influencing the material flow using a mandrel, eccentrically positioned before the deformation zone.
• Three, influencing the material flow by varying the length or the form of the bearing surface, after the deformation zone.

Apart from the above three ways of varying the velocity to obtain the bending radius, the friction between the extrusion tool and th workpiece is also an effective way to manipulate the velocity distribution of the material flow during the process.

The second process uses a special device for the bending needs, for example, the bending rolls. These bending rolls are placed directly behind the extrusion die. This bending process allows 3D bent and twisted profiles deforming using the heat exuded from the extrusion process. Bending is usually divided in two small processes for the ease factor. Profile cross section production is one part and building the bent contour the other.

Both the processes allow bending an extruded profile during the extrusion process without requiring an out of the process, initiative and time wasting. The bended extruded profiles are used heavily in the car manufacturing industry and are important ingredients of many other industrial productions in the present as well as the future.