NPE2018 Technology Focus: Sheet Extrusion
Space-saving, high-speed line for PP and PS packaging, new options in 'no-dry' PET among the highlights in Orlando.
Machine builders at NPE2018 are meeting the need for speed. Plus, the latest Super-G HighSPEED Extruders from Processing Technologies International (Booth W6744) have a significantly reduced footprint, resulting in the highest extrusion output/ft2 in the industry, the company claims. This compactness is made possible by introducing an optional tuck-under motor on these models, which are used for processing PP and HIPS for packaging. Several machines have already been installed in the U.S.
PTi’s Super-G SGHS3000-36D model on display features a vertical U-configuration and tuck-under motor to reduce the machine’s footprint by more than 33% to 12 ft, 8 in., vs. 17 ft, 7 in. for the original model. The Super-G SGHS3000-42D model is also offered with the tuck-under option and shows a comparable footprint reduction and similar output gains.
The Super-G SGHS3000-36D has a 500-hp motor and runs at a maximum speed of 1000 rpm, while the Super-G SGHS3000-42D has a 600-hp motor and runs at up to 1200 rpm. For processing PP, the Super-G SGHS3000-36D has a production output of approximately 3000 lb/hr.
There is a new option for “no dry” PET sheet systems. The STARextruder series from Battenfeld-Cincinnati (Booth W2771) features a three-part processing unit: a single-screw zone for material plasticating; a planetary-roller section for degassing under high vacuum; and an optimally dimensioned discharge zone. The planetary-roller degassing zone reportedly offers highly efficient degassing of the melt. The melt is rolled out in very thin layers, creating an extremely large surface area. Both effects are said to counteract degradation of the materials and significantly contribute to product quality.
Sheet processors can switch from PET to PP or PS processing on this extruder without a screw change. PET bottle flakes can be processed without pre-conditioning. The process has recently been issued a letter of non-objection by the FDA. The STARextruders are available in sizes of 3.5, 4.75 and 6 in., with output ranges from 1300 to 2600 lb/hr.
Gneuss Extrusion Technology (Booth W6473) is showing a complete Gneuss Processing Unit (GPU) comprised of a Multi Rotation System (MRS) 130 extruder, a fully automatic melt-filtration system (RSFgenius 150), and a VIS online viscometer. The line is made for processing undried, uncrystallized PET at up to 2000 lb/hr.
Gneuss now offers a new foam module that permits processors to quickly switch from solid to physically foamed PET sheet. Foam sheet with a weight reduction of 50% can be extruded (depending on the process) with a consistent cell structure and mechanical properties from up to 100% post-consumer material.
Graham (Booth W2743) will display a Welex Evolution sheet line, a complete production line for sheeting, winding, and in-line thermoforming, equipped with XSL Navigator control. While the equipment on display at NPE2018 will be for thin-gauge PP, the Evolution system can be customized for widths from 36 to 90 in., gauges from 0.008 to 0.125 in., and throughputs to 10,000 lb/ hr. Monolayer or coextrusion systems are available, with up to nine extruders.
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