Distribution centers handling virtually every kind of product are implementing more automated stretch wrapping machines than ever before, says Mike Schoenberger, product manager of ARPAC’s stretch machine group.
“It’s a marked transition from hand-applied stretch wrapping,” he explains. “Companies have become better educated about how to apply the stretch film to maximize load containment.”
This transition marks the latest evolution in pallet load restraint, Schoenberger says. Just a decade ago, companies moved from strapping (and other means) to secure a load to a pallet to wrapping stretch film around the load by hand.
Stretch film tightly unitizes a load, thanks to its continuous attempts to contract back to its unstretched state, he adds. However, “the strongest containment forces simply can’t be achieved by a person. An operator with a roll of hand wrap can only get maybe 10% pre-stretch, whereas a machine can easily reach 200% to 300% pre-stretch,” Schoenberger says. That higher percentage of pre-stretch also means less film is required, resulting in significant cost savings.
Many DCs learned that lesson the hard way, when hand-wrapped loads came apart in transit and the contents returned as damaged goods. In addition to the cost of returned, unsalable merchandise, hand wrapping by operators as they complete their picks, cuts into lines-per-hour-picked productivity, he adds. “It can be physically demanding to hand-wrap a load, because it requires bending, stretching and reaching,” he says. “Those actions can lead to injuries, down time and OSHA recordable incidents.”
In addition to the cost savings, the automated equipment itself has steadily dropped in price while gaining in functionality. Today’s machines can easily be pre-programmed to adjust film delivery tension to match the requirements of each unique load. Although the pre-stretch film amount is the same, dense products require a tighter application of film, while lighter, more delicate items (or cardboard cartons that aren’t completely full) require less as to not crush the load.
Understanding and establishing each DC’s unique force-to-load profiles is a critical point of the user education process, Schoenberger says. “Some companies are so excited about the switch over to automation that they don’t take enough time for testing and learning how to wrap each load before flipping the switch.”
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