Patent ID: 6898954
Filing Date: 2005-05-31
Classification: B21C

Abstract:
1. An improved extrusion apparatus comprising: an extruder comprising a die having an exit, wherein said extruder is capable of extruding materials; a supply of inert or partially inert gas and/or biphasic inerting media that contains about 3% or less oxygen; means for introducing inert or partially inert gas and/or biphasic-inerting media near or at said die exit during extrusion; at least one sensor near said die exit to detect oxygen in an environment near the die exit; analyzing means to analyze the amount of oxygen in said environment; controlling means for regulating flow rates of said gas and/or biphasic inerting media; and wherein the flow rates of said gas introduced at or near said die exit is controlled to be within a range between about 500 to about 2500 standard cubic feet per hour.