A tapered tool bends the piece into its desired shape.
Bending is a procedure for forming a flat, sheet metal workpiece. It immediately follows cutting in the processing chain. The workpiece lies on a bottom tool with a v-shaped opening. A wedge-shaped tool (punch) presses the workpiece into the v-opening and thus bends it to the desired angle.
During stamping, the stamp presses the workpiece into the die with a pressure that is much greater than during air bending. Since the stamp and die have the same angle, the workpiece is “stamped out”. As a forming process, stamping allows very high angle precision. Different sheet thicknesses and spring backs of the material are balanced out through pure bending force. The Bystronic pressbrakes generate an extremely precise pressure. This creates a stamping process of the highest quality. In addition, smaller radii and shanks can be generated than with air bending.
During air bending, the upper tool presses the workpiece into the bottom tool opening, however without bottoming. The workpiece rests solely on the two edges of the bottom tool during the entire bending process. The bending angle is determined by how deep the top tool plunges into the bottom tool. Air bending permits bending at various angles without a tool change.
A Bystronic has long used dynamic crowning on the Xpert model range pressbrakes. This unique compensation system adjusts the curvature of the lower beam automatically during bending. State-of-the-art dynamic crowning makes this correction in real time and with the latest sensors. Users can therefore achieve exact, constant bending results, and this even with bent parts that are more than 3 meters long.
Precision is the most important yardstick for pressbrakes. Slight deviations from the desired bending angle are physically unavoidable. The bending angle can either be basically inexact or can vary across the entire bending length. During air bending, compensation systems balance out these errors. Bystronic uses the unique hydraulic dynamic crowning technique on its pressbrakes: The stamp and die are specifically curved to balance out the deformation caused by the bending process. Another decisive factor is the behavior of the workpiece during bending. For precise bending results, state-ofthe- art sensors provide all required information to the pressbrake controller. This data is evaluated here and an intelligent bending process is implemented thanks to automatic corrections.