Lantech unveils non-stop shrink-wrap technology

Technology firm Lantech is launching two new continuous-motion shrink-wrap machines designed to cut processing time and limit the need for line stoppage.

The new SW-2000 belt-infeed is designed to tame the temperamental shrink-wrap process, while the SW-3000 flight-lug machine features on-the-fly tracking adjustment and side-seal/cross-seal systems that never need cleaning. The firm claims that both innovations are ideal for contract packagers and retailers.

The machines deliver rates up to 60 and 75 packs/minute, respectively, and are especially suited for end-of-the-line wrapping where uptime is at a premium, changeovers frequent, and packages come in all shapes.

"These machines take all the 'art' out of shrink wrapping and will change market perceptions that shrink is a temperamental wrap process," said Jean-Louis Limousin, Lantech's business leader for shrink wrap. "During our development programme, we visited hundreds of wrapping operations and learned that rework rates of 20 per cent were common. Cleaning the side seal system is the most often cited cause of line stoppage.

"What's more, users realise that downtime to clean the seal system is compounded by the cost for rework on the packages wrapped while the seal system was compromised. Our design addresses these issues with simple setup, a maintenance-free side seal, and excellent overall pack quality."

The two new machines are suited for polyolefin, PVC and LDPE films. Min/max package dimensions for the SW-2000 are (L x W x H): 3" x 1" x 1/8" to infinite/random x 15" x 6". The SW-2000 provides electronic product spacing for random product lengths, and can be used with belted, flight-bar or flight-lug infeeds. The flight-lug infeed on the SW-3000 provides tighter control of unstable products and accepts the same minimum package size to a maximum of 40" x 15" x 6".

Both machines operate 'on demand,' so intermittent motion packaging is accommodated as easily as continuous motion.

The adjustment-free rotary side-seal system common to all Lantech shrink machines cuts and seals simultaneously at minimum temperature to avoid melting film on components that could degrade performance or cause a stoppage. The unique system requires setting of only temperature. Two different wheels, adjacent to each other, trim and fuse the side seal.

Trimming requires no heat, so the seal head can be threaded and checked 'cold' for operator convenience. Likewise, the sealing wheel does not cut the film, so seal temperature can be set for the minimum necessary, eliminating the tendency for film to melt on sealing surfaces.

Cross-sealing is reliable and maintenance-free with a seal bar that cuts and seals with separate heated surfaces. The separate sealing surfaces operate at minimum required temperature.

The side seal head minimises trim waste with the Sure-Trac electronic film drive system, which gives excellent control of the web and allows the narrowest possible film width to be used for the application. Variable frequency drives on the machine provide electronically controlled film collapse, product spacing, and tension control on the trim wind - all settable through the machine's control.

Both machines have an adjustable inverting head. The patent-pending film carriage eliminates film waste during setup by using logical settings based on package height/width, with inch-denominated scales on the machine for carriage height, inverting bars, etc.

"All settings are related to package dimensions in a systematic way," said Limousin. "Once you have the package height/width dimensions, you set the scales on the machine, thread film, put product on, and you should be ready to run with little or no tuning, which can be accomplished at the control with the machine in cycle."

All setup parameters are displayed in a single view on the color touch-screen LCD control, mounted on a swing arm. Up to 16 setups can be stored in memory. The control has three levels of access, all password protected.

Options for the machines include print registration, film support inverter rods, gated infeed, spacing conveyors, and a compact, powered center folder requiring just 8 sq ft of floor space.