An apparatus for forming first and second shaped articles from first and second sheet metal blanks (800, 802), comprising: a first die having first forming surfaces for forming the first shaped article from the first sheet metal blank and having a first seal bead disposed along an edge region surrounding said first forming surfaces, the first seal bead for peripherally sealing between the first die and the first sheet metal blank, the first die having a first recess defined in the edge region thereof, the first seal bead extending along a first surface through the first recess; a second die having second forming surfaces for forming the second shaped article from the second sheet metal blank and having a second seal bead disposed along an edge region surrounding said second forming surfaces, the second seal bead for peripherally sealing between the second die and the second sheet metal blank, the second die having a second recess defined in the edge region thereof, the second seal bead extending along a second surface through the second recess; and a nozzle body having a conduit extending therethrough for conducting an expansion fluid through said nozzle body, the nozzle body shaped for being received within a channel that is formed when the first die and the second die are brought together into a closed condition such that the first recess and the second recess are aligned one with the other, said nozzle body having first and second sealing surfaces (200, 202) that are joined along opposite side edges (204, 206) of said nozzle body, said opposite side edges (204, 206) converging one toward the other along an insertion direction of said nozzle body, wherein the channel is shaped such that, when the nozzle body is inserted along the insertion direction to a sealing position within the channel, the first seal bead forms a seal between the first sheet metal blank and each side edge (204, 206) of said nozzle body, and the second seal bead forms a seal between the second sheet metal blank and each side edge (204, 206) of said nozzle body. a first die having first forming surfaces for forming the first shaped article from the first sheet metal blank and having a first seal bead disposed along an edge region surrounding said first forming surfaces, the first seal bead for peripherally sealing between the first die and the first sheet metal blank, the first die having a first recess defined in the edge region thereof, the first seal bead extending along a first surface through the first recess; a second die having second forming surfaces for forming the second shaped article from the second sheet metal blank and having a second seal bead disposed along an edge region surrounding said second forming surfaces, the second seal bead for peripherally sealing between the second die and the second sheet metal blank, the second die having a second recess defined in the edge region thereof, the second seal bead extending along a second surface through the second recess; and a nozzle body having a conduit extending therethrough for conducting an expansion fluid through said nozzle body, the nozzle body shaped for being received within a channel that is formed when the first die and the second die are brought together into a closed condition such that the first recess and the second recess are aligned one with the other, said nozzle body having first and second sealing surfaces (200, 202) that are joined along opposite side edges (204, 206) of said nozzle body, said opposite side edges (204, 206) converging one toward the other along an insertion direction of said nozzle body, wherein the channel is shaped such that, when the nozzle body is inserted along the insertion direction to a sealing position within the channel, the first seal bead forms a seal between the first sheet metal blank and each side edge (204, 206) of said nozzle body, and the second seal bead forms a seal between the second sheet metal blank and each side edge (204, 206) of said nozzle body.