Food Engineering

Say good-bye to shrinking profits

January 8, 2006
New shrink wrappers save packaging material, rework, downtime and labor for dessert manufacturer.

After installing three Lantech SW-1000 intermittent motion shrink-wrapping machines, Lakeview Farms reduced downtime, labor and film consumption costs in its dessert manufacturing process. Source: Lantech.
As America's appetite for the refrigerated desserts, dips and cheesecakes made by Lakeview Farms grew rapidly over the last few years, management at the company's Bristol, WI, plant noticed that shrink wrapping was shrinking its profits. "We had a mix of five manual L-bar machines and one automatic. The shrink wrapping process took too many people, too much time and too much film," says Peter Fink, Lakeview Farms' plant manager.



The primary product in the Bristol location is ready-to-eat desserts such as pudding and gelatins. Much of the output goes into packs consisting of 12, 4-oz. single-serve cups that are multipacked in a low-rise corrugated tray and shrink wrapped. With the plant running nearly 24/6, management wanted to focus on bringing more efficiency to the shrink-wrapping operation. "We had been using shrink packaging for about five years and simply outgrew the L-bar machine technology we started with," says Fink. "Our growth was gradual, so we compensated with time and labor to maintain output with the packaging equipment we had. We endured a lot of downtime for changing the seal wires four to five times a day, and we had a lot of rewrap resulting from bad seals."

Management also wanted to address film consumption. For speed, the 13-in. long by 8-in. wide by 4-in. high packs were fed with the 13-in. dimension as length, so trim off the side seal was excessive when using 18-in., center-folded film.

"We looked at lots of different automatic L-bar machines and none of them would run for more than a couple of hours without a problem, or if they did run, the quality of the wrap was not up to our standards," says Fink. "Based on positive experience with Lantech's stretch wrap machines, we agreed to try out their SW-1000 shrink wrapping machines."

The wrapping machines use Lantech's Ever-Clean rotary side-seal system in conjunction with an electronic film drive. The rotary side-seal mounts a sharpened cutting wheel and a heated fusing wheel adjacent to each other on the same axis. Because the sealing wheel does not have to cut the film, the temperature can be set for the minimum needed to fuse or laminate the seam, instead of melting the film to a liquid state, which causes film build-up on the sealing surfaces.

Variable frequency drives on the machine provide electronically controlled film collapse and product spacing, programmed through the machine's control. The trim winder for the side seal is tension controlled. It only pulls on the trim when it senses slack. There is no clutch to adjust to compensate for the changing diameter of the trim spool, so a very narrow edge trim can be used without tearing it and causing machine stops.

Bag length is set in the machine's control. Fink says this saves at least 2 in. of film per bag. And with the packs under better control by the machine, they can now be fed with the 8-in. dimension as length, so trim at the side seal is reduced by several inches.

Since installing three of these machines to replace the L-bar machines in the Bristol plant, downtime, except for roll changes, has almost been eliminated, says Fink. In addition, three employees have been reassigned from packaging, while reduced film consumption helps offset the cost premium over L-bar machines.

Running 60-gal., 18-in., center folded Bemis Clysar film, Lakeview Farms currently puts about 10 to 15,000 cycles per day on each of the three machines. "We're producing more, with three fewer operators on the line, less material and virtually no rewrap," says Fink.

For more information: Lantech; 800-866-0322; sales@lantech.com