Hydromechanical deep drawing of metal sheet - uses two concentric punches for producing complicated shapes

摘要

The deep drawing of metal sheet is carried out hydro-mechanically by using a pressure chamber (1) filled with oil (2) supplied through an inlet (3). The metal blank (5) is placed over the pressure chamber (2) which is sealed with a sealing ring (4). A pressure plate (6) which forms a guide for the main punch (10) holds the blank (5) in place. A second punch (8) slides in a hole in the main punch (10). The press pushes the inner punch downwards and forms a small cylindrical depression in the blank (5) until the flange (11) of the inner punch abuts against the end face of the main punch. The two punches then move together and form a larger cylindrical shape.