CHICAGO — Blown film equipment suppliers are making it easier for processors to convert an ever-growing range of resins into exciting new film constructions.
NPE 1997 exhibitors displayed equipment refinements that make it easier to control film extrusion and to switch materials and film products quickly.
``Output is important, but more important to us is quick changeover capability,'' said Bill Swinimer, president and chief executive officer of film producer Uniplast Industries Inc. ``Our average film order is under 4,000 pounds.''
Swinimer said NPE exhibitors displayed numerous technologies to make a film processor's life easier. Among his highlights were better controls for melt, gauge and winders, better resin blending systems, and improved air rings. These and other improvements simplify the film extrusion process and allow better quality control when making grade changes, he said in a telephone interview from Uniplast's head office in Orillia, Ontario.
Alpine American was one exhibitor boasting about the flexibility of its film extrusion line. The Natick, Mass., firm ran several three-layer constructions at NPE in Chicago.
``Resins are changing quickly,'' said George Bambara, sales manager. ``Customers want the opportunity to run new metallocene resins and conventional materials, too.''
Bambara said the Alpine line running at NPE demonstrated its flexibility in extrusion and die design. It made 14 different structures during the show using various combinations of metallocene resins, high-molecular- weight high and low density polyethylenes and LDPE supplied by six resin companies. It changed the bubble from low stalk to high stalk and back again by changing the die gap and internal bubble cooling column. The switches took less than 55 minutes, he claimed.
Bambara said contrary to some opinions, Alpine proved its groove feed extruders can run metallocene resins. The firm did not change extrusion screws during the show and said changeovers are easy using its U.S.-made AES extrusion control system. Alpine also debuted its U.S.-made turret winder and surface winder.
Kiefel Inc.'s blown film line at NPE featured various automatic controls for gravimetric blending, extrusion, and winder tension and pressure, noted Steven Engel, president of the Wrentham, Mass., firm. It redesigned its air lip for uniform gauge and high ouput. Its line included a 16-port spiral die for melt splitting and mixing in the die, allowing a more uniform gauge.
Kiefel made monolayer high-molecular-weight PE film at rates up to 940 pounds per hour using a 100-millimeter extruder and 225mm die, Engel said in a post-show interview.
Atlantis Plastics Inc. officials said they were impressed with Battenfeld Gloucester's seven-layer line running at NPE. It offers real-time process control, high speed and high output, said Jerry Roberts, plant manager for Atlantis' Cartersville, Ga., film plant.
The Gloucester line is well-suited to barrier films and to sandwich low-cost materials between premium resins, Roberts said in a telephone interview.
Atlantis production manager Kevin Featherston said the Acccurablend gravimetric blending technology on the Gloucester line allows precise control of materials, a boon to quality control.
``Our customers want assurance the material levels are right,'' Featherston said.
The Gloucester line featured a low-profile die, adjustable lip air ring, an air-bearing bubble cage, noncontact air-board collapsers and a dual-turret winder. World Class Film Corp. of Yonkers, N.Y., announced at the show that it bought the $2.6 million film line.
Roberts said he also was impressed with Gloucester's new bag-making machinery, which in his opinion offers higher speed, more controls and easy set up.
Several other suppliers said their products improve film extrusion flexibility, including:
Brampton Engineering Inc.'s Dial-A-Gap die-gap adjusting allows quick changeover between resin systems.
Davis-Standard Corp.'s WesJet Air Ring II can run low-melt strength materials.
Future Design Inc.'s Window Everest Bubble protects the frost line from ambient and shadow heat.
Harris Instrument's Scan-A-Line measurement systems for film are impervious to smoke, dust and other contaminants.
Macro Engineering & Technology Inc.'s new D10 dual lip air ring for special cooling applications such as with low melt strength materials.
Plast-Control Inc.'s new controller for individual layer thickness in coextrusions.
Randcastle Extrusion Systems Inc.'s new lab-size blown film lines for product development.