The performance of barrier melting sections for single-screw extruders

Screws with barrier flighted melting sections are preferred for melting and extruding polyethylene resins into films using either a smooth-bore or grooved-bore single-screw extruder. Barrier melting sections were developed in the 1960s, and since then they have been widely used commercially to increase an extruder’s melting capacity and decrease the extrudate temperature. Higher rates and lower discharge temperatures are advantageous to many applications, including blown film, blow molding, pipe, and other profile extrusions. This paper presents an experimental study that shows how four screws with two barrier flight undercuts and two metering channel depths affect the barrier melting section performance.