Sheet Lines Feature 'No Dry' Capabilities
Vented extruder design degasses material to make pre-drying unnecessary.
Sheet extrusion lines from Germany’s Breyer GmbH can be equipped with vented single-screw extruders that when running hygroscopic resin allow the material to be processed without needing to dry it first. The melt will become optimally degassed, a precondition for processing sheet and films meeting highest quality demands of the worldwide market.
Breyer’s lines can also be furnished with a roll stand that adds flexibility to the line by allowing it to run sheet in a variety of finishes, including matte and polished on both sides. The quick-exchange capabilities of the first and center calender roll allow the stack to be converted as needed. Depending on the total output, calenders can be furnished with three and four rolls with different roll diam. What’s more, the third calender roll can be skewed during production to manipulate the residence time of the sheet around the center roll.
Breyer’s gap-control system allows a precise and fast adjustment of the gap by changing the extrusion speed at the touchscreen (pressure-control mode). The operator changes the speed value on the touch screen based the new product thickness, and within a matter of seconds the product is set to the desired thickness. Breyer says this approach is more efficient and cost-effective vs. conventional gap adjustment systems, which require the operator to adjust the speed separately, after the gap adjustments have been implemented.
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