People have been bending and curving metal for centuries. One of the latest, most advanced cold bending techniques is stretch bending; a very accurate technique developed in the aerospace industry and used because of its benefits in product and surface quality.
Kersten is the first company that makes this bending method available for other industries as well.
Stretch bending technology is suitable for tubes and (extruded) profiles in aluminium, steel and stainless steel.
Kersten develops and manufactures its own special tooling to bend even the most delicate aluminium profiles without damaging the surface and with just minimal deformation of the cross section. Even if it concerns very small radii.
Stretch bending is complex and requires real craftsmanship. Recently Kersten invested in two highly advanced stretch bending machines of 20kN and 60kN.
Stretch bending technology allows us to bend:
- Tubes and sections up to 500mm in width
- Aluminium extrusion profiles, aerofoil louvres, steel and stainless steel tubes and sections
- Tubes and profiles with a maximum length of 13 meters
- Additional services like 3D contour cutting, welding and heat and surface treatments (incl. wood finish)
video stretch bending
- Set up
The machine and special tooling are prepared
Placing the tube/profile in the machine
Both ends of the profile are inserted in the gripper jaws.
The gripper jaws stretch the profile. There is a constant tension on the profile
While maintaining the tension, the gripper jaws wrap the profile around a form die.
When the required radius has been reached, the jaws release the profile. The machine operator needs to keep in mind that the profile will rebound a little bit after it is being released.
A template is used to check if the profile has indeed the correct radius.
Benefits of stretch bending
- Perfectly contoured products
- No scratches/damages of material surface
- Minimal deformation of the cross section
- Speed – so less labour hours
- Little to no overlength needed
- Thinner wall thickness needed
- Conveyor systems
- Side panels
- Side Panels