Apparatus for sealing an end portion of a tubular workpiece in a mold for internal high-pressure forming

摘要

Apparatus for sealing an end portion of a tubular workpiece in a mold for internal high-pressure forming of the workpiece, includes a housing having a pressure compartment in fluid communication with an interior space of the workpiece. Hydraulic high-pressure fluid is supplied from a pressure source to the pressure compartment by a pressure application unit which further includes a pressure piston received in the pressure compartment and defined in the pressure compartment by an effective piston area which is greater than a cross sectional area in the interior space of an end portion of the workpiece. At least indirectly connected to the pressure piston is a sealing mandrel which interacts with the end portion of the tubular workpiece. A check valve is disposed in a passageway between the pressure compartment and the interior space of the workpiece for blocking in a direction to the pressure compartment.