For example, reports the manufacturer, one processor of mLLDPE coextruded film was limited to a rate of 15 ppi (pounds per inch of die circumference) due to high ambient temperatures and the limits of its dated cooling technology. During a pilot line trial, rates of 23 to 24 ppi were demonstrated with an improved thickness control of +/- 4%, according to D-S, with the result that this processor intends to retrofit a triple lip system with a new die to its existing Davis-Standard coextrusion machines.
The air ring is said to offer advantages in terms of output, gauge control and film quality. The design of these air rings includes one air ring, blower, chiller, and associated equipment versus the standard two of each. Processors have a wide production range with a BUR (blow up ratio) of 2.0:1 to 4.4:1. Performance increases in the 30-40% range are common, says D-S. Processors also benefit from simplified maintenance. The air ring is available on new lines or as a retrofit to existing Davis-Standard lines.
Processors interested in learning more about the triple air ring or who would like to schedule a pilot line trial can contact Rick Keller. —MPW Staff