In-situ foam core structural articles and system for forming

A system for forming an elongated structural article, comprising:

• a profile extrusion die for continuously forming a at least one axially extending profile defining at least a portion of a wall surrounding a cavity;
• an elongate tubular shaping mold located axially downstream of the profile extrusion die, and sized to receive and support a length of the at least one axially extending profile as it continuously passes there through;
• a spider located in an inlet end of the shaping mold within the profile cavity, to support the profile extrusion as it passes there over;
• at least one bead dispenser extending through the spider to introducing pre-expanded beads into the profile cavity downstream of the spider as while the profile extrusion continuously passing through the shaping mold;
• at least one steam tube extending through the spider having an input connectable to a steam source and a steam outlet section oriented within the profile cavity in alignment with the profile axis, downstream of the introduction of pre-expanded beads and within the shaping mold for introducing steam into the pre-expanded beads within the profile cavity while the profile extrusion continuously passing through the shaping mold;
• and
• control valves for regulating the flow of pre-expanded beads and steam into the profile cavity, order to introduce then heat the pre-expanded beads with steam while continuously passing through the shaping mold causing the beads to expand, melt together and bond to the profile extrusion, forming an elongated structural article when cool and cut to length.