High thermal transfer hollow core extrusion screw assembly

A screw for a processing device, comprising:

• an elongated, axially rotatable shaft having a hollow core and presenting a connection end operable to couple the screw with a drive, and bearing structure at the opposite end of the shaft, there being an axial bore permitting insertion of a heat exchange media delivery tube through the bore and into said hollow core;
• and
• elongated, helical fighting extending outwardly from said shaft along the length thereof,
• said screw having a flighted inlet section extending from said connection end to a terminus, and a flighted central section extending from said inlet section terminus towards said bearing structure, said axial bore terminating substantially at said inlet section terminus, so that said heat exchange media does not heat said inlet section of said screw,
• at least a portion of said helical fighting section having a pair of opposed, spaced apart wall segments extending outwardly from the shaft with a hollow helical area between the opposed wall segments,
• said flighting having an internal helical groove along the length thereof and presenting an outer groove open end and an inner wall, with a series of spaced apart apertures through said inner wall communicating said helical groove with said hollow core;
• and
• an outer wall spaced from said inner wall and closing said outer groove open end.