Nordson Extrusion Dies Industries, Chippewa Falls, Wis., has developed enhancements to extrusion coating dies and internal deckles that make it possible for converters to reduce edge bead
with low-melt-strength polymers while maintaining coat-weight uniformity--two goals that reportedly have often been mutually exclusive with such resins.
* Motorized drives with built-in edge bead
Remove the skirtings if you want these to cover the edge gap, a plastic edge bead
is availablefor this if you wish to leave the skirting.
The Flex-Master's 65 mm and 75 mm coextrusion station utilizes a feedblock and 1,500 mm die with internal deckles for edge bead
The system is based on a unique platform developed by the company, which detects particles, coat and develop-related defects and EBR (edge bead
removal) results with zero-added particles.
A plastic edge bead
is available for this if you wish to leave the skirting.
Internal deckle parts provide independently adjustable components that seal off portions of the internal flow channel and can be positioned to minimize edge bead
. The redesigned EPC die also offers rapid and accurate changes in width; an easily inserted scraper to remove buildup; and fast removal of the deckle system for 'split and cyan.'
 employ a two-dimensional isothermal, Newtonian model to compute the neck-in and "edge bead
One makes the large width adjustment of both internal and external deckles in tandem; a second, smaller motor repositions the internal deckle blade to reduce edge bead
. A new spring-loaded device applies pressure to seal the external deckle at the die lip and prevent leakage.
The dimensionality of the film problem determines, as shown in Table 1, whether two important phenomena can be predicted by a given model: i) neck-in, a downstream reduction in the film's width; and, ii) edge bead
, an increase in the thickness of the film at its edges.
Its first seven-layer line in Lewisburg, Tenn., has five extruders plus a small sixth machine that extrudes edge bead
out of trim waste.
Next, viscoelastic effects on neck-in and edge bead
phenomena were investigated.