Extrusion International 4-2026

31 Extrusion International 4/2026 FILM EXTRUSION FlexiPET – Redesigned Demo Line for PET Thermoforming Sheet SML announces the launch of the FlexiPET, a brand-new production-scale demonstration line for thermoforming sheet located at SML’s Technology Centre. The line features a completely redesigned machine architecture, and delivers smart innovations at every level: most notably SML’s new twin-screw extruder TSE80 for polyester, a modernised roll stack, and the new W650 winder. T he FlexiPET is a co-extrusion sheet line con gured for a classic 3-layer structure (A/B/A), but which also has the versatility to operate as a 2-layer line (A/B) as required. Extrusion excellence: TSE 80 combined with high- performance vacuum unit “At the heart of the line lies the new TSE 80 – a state- of-the-art parallel co-rotating twin-screw extruder de- signed in-house by SML and speci cally optimised for PET,” explains Martin Kastner, R&D Engineer at SML. Equipped with a low-maintenance, water-cooled main drive delivering 348 kW, the TSE 80 achieves an output capacity of up to 1000 kg/h for PET. The TSE 80 demonstrates exceptional material versa- tility. It is optimised for processing large volumes of ma- terials with low bulk densities – such as akes or regrind. The concept is also an excellent choice for processing PET/PE akes, as well as PETG and its post-industrial ake stream (GAG). With its compact design, the TSE 80 ensures high rates of energy ef ciency. In addition, the short residence time in the extruder retains the natural, clear colour of PET, preventing the yellowing of the lm. To ensure the highest melt quality for processing PET without pre-drying, the TSE 80 is combined with SML’s high-performance vacuum unit. This frequency- controlled two-stage vacuum system employs a roots vacuum pump for high volume ow rates with a dry- running rotary screw pump for low pressure levels. This con guration achieves absolute pressure levels as low as 1 mbar. Due to the dry-running vacuum pumps, the unit ensures high levels of energy ef ciency and envi - ronmental compatibility. A gravimetric batch blender with three stations for main components (virgin, akes, regrind) and two ad - ditive dosing stations offers expectional exibility for complex formulations. The co-extruder in the FlexiPET line is an SML single- screw extruder (ES 60/28D) powered by a 64 kW main drive motor. It is designed for processing pre-dried ma- terial with an output of up to 200 kg/h for PET. Precision calendering Downstream, the horizontal roll stack ensures a high speci c output, even for thin gauges as low as 150 µm. It uses the proven Smart Parallel Gap (SPG) polishing roll- er technology for superior thickness tolerances. “A major innovation is the roll stack movement, equipped with servo positioning drives and lin- ear guides, which enables precise, 100 % re- producible positioning in both the horizontal