Enhancing Blown Film Product Quality

Xaloy? Custom Screw Design and Vented Conversion Reduces Melt Quality Issues by 90%

Powder PVC is commonly used in the pipe, wire and cable, and construction industries. However, it poses a unique challenge when it comes to designing a single-stage screw for extrusion. The flight design, particularly in the feeding area, is crucial because of how the powder packs out. Blown film extrusion lines typically don’t require venting due to the high head pressures generated at the die. Nevertheless, in some cases, venting is essential for achieving optimal product quality.

THE CHALLENGE

A blown film manufacturer in the western United States faced an issue with pin holes in their film on one of their production lines due to the presence of moisture and air entrapment. This issue resulted in receiving multiple complaints from their customers. They were processing powder polyvinyl chloride (PVC) with added plasticizers and stabilizers using a 3.50” 36:1 barrier screw equipped with a mixer in a non-vented extruder. Seeking a solution to their melt quality problems, they reached out to Xaloy for assistance.

Luckily, Xaloy had the right solution for them. [click to continue reading...]