In making a determination as to whether to slit in-line or off-line, Klein advises converters to consider how much the slitter set-up will slow them down. Long-run jobs with few changes are the best in-line slitting candidates, he notes.
The productivity of slitting itself is buoyed by sleeker approaches to supporting components and operations. Titan's Wolf explains more sophisticated handling equipment can strip, reorient, and stretch-wrap finished rolls and then place them immediately onto a pallet. Burris' Sellers cites a trend toward larger master rolls that reduce labor simply because they run longer.
Haste without waste
To prevent the quality of a finished slit roll from becoming lost in the flurry of faster, more efficient operations, suppliers offer waste-saving materials and monitoring strategies.
Wolf highlights PLC-programmed digital drives that allow smoother "soft-start" material transitions on unwind and rewind operations. In addition, newer software allows slitting operations to be hooked up to a modem for trouble shooting, and can maintain a history of any job from the master roll down to the finished roll, he says.
Tidland's Klein emphasizes automatic knife positioning as "a must" for printers of four-color process work who can't afford slitting errors on higher-cost materials. He cites shear slitting with a pair of circular knives as a higher-quality route. The knives are more expensive than razor blades, but last longer due to their scissor-like, self-sharpening capabilitiesa particular benefit to industries needing dust-free packages, such as food and medical industries, he says.
Quality must also shine through increasingly broad roll-size parameters. "We are seeing and responding to requests for ever-increasing finished roll diameters, the capacity to accurately slit narrower widths with good and consistent roll density and wound in tension at maximum speeds," states Bob Preddy, vice president of sales at Webco Engineering, Westboro, MA.
Hands-on, hands-off safety