Method and apparatus for calibrating a metal profile blank

A calibration system (300) for calibrating an extruded hollow profile (200) by plastic deformation from an initial shape to a predetermined final shape,

• wherein the extruded hollow profile (200) comprises at least one hollow chamber (220) extending through a longitudinal direction (L) of the extruded hollow profile (200), the at least one hollow chamber (220) having openings (221) at opposite ends of the extruded hollow profile (200),
• wherein the calibration system (300) comprises:
• a liquid (310) for filling the at least one hollow chamber (220),
• a first closure device (320) and a second closure device (320) configured to close the openings (221) to confine the liquid (310) in the at least one hollow chamber (220),
• a die tool (340) configured to define an external boundary of the predetermined final shape of the extruded hollow profile (200), and
• a pressing tool (330) configured to move the die tool (340) to compress the extruded hollow profile (200) such that an internal pressure (Pi) in the at least one hollow chamber (220) is increased and the extruded hollow profile (200) is plastically deformed into the predetermined shape.