Sigma Plastics Invests Big at NPE2018
PE film giant Sigma enters FFS market with six new lines from W&H. Makes other purchases as well for numerous plants.
At NPE2018, PE film processor Sigma Plastics Group announced significant equipment investments along with an entry into an all-together new business.The film extrusion powerhouse said six new Optimex FFS lines it ordered from Windmoeller & Hoelscher (W&H) will be up and running at its Republic Bags plant by the end of the summer, producing blown film for form-fill-and-seal (FFS) sacks. This installation marks Sigma’s foray into the FFS market. The lines will produce about 45 million pounds of film annually, printed and gusseted.
Meanwhile, Sigma’s McNeeley Plastics plant has ordered two Varex II blown film lines—a 3-layer and a 5-layer system. The latter will be equipped with W&H’s Turboclean resin-purging and quick-changeover system, and a Filmatic S winder with reverse-wind capability. This investment will support McNeely’s expanding business in converter-grade films. And last week, Sigma started a five-layer Varex II line at its ISOFlex plant.
In related news, Sigma also announced it has ordered two high-output five-layer polyolefin-dedicated (POD) lines from Reifenhauser for its BJK plant, both equipped with the machine builder’s Ultra Cool IBC and Ultra Flat patented in-line flattening system. Sigma also said it bought another two lines from Reifenhauser for its Allied Extruders division: a three-layer high output system and a five-layer POD line. Both lines will also be equipped with Ultra Cool and Ultra Flat technology.
Sigma has also ordered new three- and five-layer lines from Hosokawa Alpine American, according to that machine builder. The three-layer line was recently commissioned, Alpine said.
Just like selecting the extruder size and drive combination, the L/D should be carefully evaluated.
All things being equal, PET will outperform PBT mechanically and thermally. But the processor must dry the material properly and must understand the importance of mold temperature in achieving a degree of crystallinity that allows the natural advantages of the polymer to be realized.
A poorly designed profile die—one that does not permit the part to be extruded with the same dimensions from run to run—coupled with a lack of understanding of the extrusion process, is a recipe for scrap generation.