Article from Plastics Technology’s June 2010 issue
appleton performance packaging
‘Modest’ Investment, Big Payoff
For Blown-Film Processor
In blown film, there is certainly more than one way to skin a cat. But Appleton Performance Packaging (appletonideas.com), actually skinned a clowder of cats at its Milton, Wis. plant, boosting film output and quality while also speeding up product changeovers by making recent upgrades to key components on its blown film lines.
Milton is home of one of Appleton’s three film plants, the other two being in nearby Rhinelander, Wis., and in Turners Falls, Mass. The Milton facility houses three single-layer lines and one 3-layer co-extrusion line primarily producing specialty lamination films for food packaging and other high-end applications. The processor has 3-layer coextrusion and barrier capacity at its other locations, including a nine-layer line in Rhinelander. The Turners Falls and Milton plants initially were owned by New England Extrusion, which was purchased by Appleton a few years ago.
In Milton, one line is furnished with a 400-mm die package to produce film in layflat widths from 32-60 in.; a second has a 450-mm die for layflats from 40-80 in.; the third a 500-mm die for 43-87 widths. “Our mission is to have the top of the line technology in all of our plants,” remarks Bryon Task, Appleton’s plant manager. “The lines in Milton were state of the art when we bought them, and we fully intend on keeping this equipment state of the art as they get older.”
In blown film, output and gauge control are king. When supplying film
that has to be laminated, controlling thickness fluctuations is even more critical, as even small swings can foul up the converting process, generate scrap, and create unhappy customers. In the past, processors might compensate for thickness variations by “overengineering” the film so that it meets the customer’s specs, a tactic that consumes more resin than is really required. But with increasing PE prices, that’s just throwing good money after bad.
BUY ALL NEW OR RETROFIT?
So faced with aging lines and more-demanding customers, Appleton weighed its alternatives and decided that retrofitting its current capacity with critical components supplied by Addex Inc., Stoughton. Mass. (addexinc.com), was its best course of action.
Earlier this spring, Appleton completed installation of Addex’s Internal Gauge Control (IGC) system—IBC pancakes with air-controlling sliding fingers that target cooling at the melt as it exits the die—teamed with the supplier’s Digital Internal Bubble Cooling System (DIBC), a five-sensor system teamed with a high-speed, servo-controlled air-regulation valve that allows for split-second corrections to changes in bubble size at or below the frost line, where the bubble size is not final.
The investment to refurbish all three lines was significantly less than what it would have cost Appleton to buy one brand new blown-film line, but Task says they are now producing higher quality film at increased throughputs.
On the 400-mm line, the IBC package is actually a five-pancake
arrangement in which two of the stacks have the sliding fingers (the others
are strictly intended to enhance throughput). Running at low blow-up
ratios of 1.43 to 1.95:1, Appleton saw an increase in output of 25% on some products.
“On all the installations we have seen a definite increase in bubble stability,”
notes Task, adding that stability is critical to boost production. On the
subject of gauge control, Task reports a 50% improvement in gauge at 3
In Milton, Appleton runs more than one hundred different products on its three lines, when you take into account the all variations of blends, layflat widths, thickness, etc. That places an imperative on product changeover time…simply put, the faster the better. “There has been a huge reduction in time in getting the film to the right layflat width with the digitial IBC control system vs. the analog system we had,” remarks Task. On the 400-mm line, moving from 49-in. layflat to a 36-in. layflat took 10 seconds compared to the 10-20 minutes it took for the previous system to make the switch.
By James J. Callari, Editorial Director
Caption: At Appleton Performance Packaging’s plant in Milton, Wis, retrofitting three monolayer lines with critical components supplied by Addex results in significant improvements in output and quality, and more efficient product changeovers, notes Bryon Task, plant manager