Extrusion International 6-2025

41 Extrusion International 6/2025 New Twin-Screw Extruder Unveiled at K 2025 SML is expanding its extruder port- folio with the introduction of a co- rotating twin-screw extruder (TSE). This addition marks a signi cant enhancement of SML’s offerings, allowing the company to provide a more comprehensive range of extru- sion solutions to its customers. The brand-new TSE is SML’s an- swer to the increasing demand for high-output capacities for polyole- ns and polyesters. “Our in-house- designed co-rotating twin-screw ex- truder is tailor-made for the speci c requirements of our extrusion lines, contributing to an exceptional lm quality,” states Hans-Jürgen Luger, Head of Research and Development at SML. Compact size bene ts energy consumption Compared to a large single-screw extruder with the same output ca- pacity, the TSE has a shorter pro- cessing unit and, thus, a smaller footprint. Therefore, less heating power is required to maintain the barrel temperatures. Because of starve feeding, the extruder drive operates at high torque over the entire output range, where it ex- hibits the maximum ef ciency. Ad - ditionally, the melt temperature can be controlled by adjusting the degree of lling. Extensive tests of the new TSE on a CPP line in SML’s Technology Centre have shown that the speci c energy input (SEI) is 10-15% lower compared to a sin- gle-screw extruder. In terms of lm quality, the gel count detected by a web inspection system could be re- duced by up to 20% for a standard CPP lm. Optimised for high-performance cast lm lines One area of application with con- siderable potential is SML’s cast lm lines. “With throughputs in the range of 1,000 to 2,000 kg/h, the TSE is ideal for our high-performance cast lm lines with end lm widths of up to 6.5 metres,” explains Elias Mayrhofer, Product Manager at SML. Clever design and low maintenance The swivel-mounted barrel de- sign allows rear screw extraction for quick and easy screw changes. The temperature control of the barrel works via ceramic heaters and air cooling – which is a precise, cost- ef cient, and low-maintenance so - lution. SML offers pre-con gured single-piece barrel designs of differ- ent lengths and with venting ports depending on the application. For the extruder screws, single-piece so- lutions or shafts with segments are available. PET without pre-drying and in-line compounding In combination with SML’s high- performance vacuum unit, SML can offer a complete in-house extrusion solution for processing PET or PLA without pre-drying. Furthermore, the TSE enables high amounts of regrind or akes to be processed as well as in-line compounding. SML Maschinengesellschaft mbH www.sml.at (Photo credit: KHP Karin Hackl) (Photo: Messe Düsseldorf / ctillmann)