Combitrack Rewinder Page 2 of 3

What are the technical challenges of film that necessitate a specially designed machine?

Film rolls can be three to five times as heavy as label rolls — while the materials are thinner, they’re much heavier because they’re more dense. That is why it’s extremely important to take ergonomics and roll changeover into account from the start.
Moreover, while the rolls are very heavy, the rewinding tension has to be extremely light, or you’ll elongate and mis-steer the web. There must be superior mechanical and electronic design.
Essentially, the machine must have all the processing attributes of a wide-web, high-capability film processing slitter-rewinder, incorporated into a pressure-sensitive label size machine.
The film also varies in thickness across the web. For example, on a 15 micron unsupported film, printing inks even a couple of microns thick can lead to a significant localized change in thickness, causing bumps or tension bands in the roll.

What is the Combitrack concept?

Combitrack adds all of the features needed for exceptional performance of a thin film inspection slitter-rewinder to the groundbreaking flexible format of the Printrack rewinder. It is an inspection slitter-rewinder that can process both film and pressure sensitive labels, but it was primarily designed to incorporate all the processing needs of film rewinding, rather than just be a modified label inspection slitter-rewinder that doesn’t really do the whole job well. Combitrack has all the tension deriving capabilities needed to serve the two, distinctly different, applications.

What are the main design improvements Combitrack offers?

Controlled riding-ironing roll pressure throughout the winding cycle

The riding/ironing roll assemblies are specifically designed to handle thin-gauge film. Therefore, the tension in the rewinding webs does not add to, or subtract from, the riding/ironing roll pressure — all the way from beginning at the core to finishing at the outside diameter. This is a critical, major point of comparison with respect to Combitrack’s competition.

Rewinding shafts are located at heights to suit the operator in hour-after-hour production, thus greatly reducing operator fatigue and changeover times.

The Combitrack web flow has been laid out to keep the rewound rolls at the most ergonomic height for the operator. This means finished roll unloading, new core loading and lead-end taping are done at the most effective heights to avoid repetitive strain injury to the operator. On competitors’ modified label inspection slitter-rewinders, the lower roll is usually far too close to the floor so it’s very difficult for operators to remove high-weight/density rolls from the rewind shaft and to reload the new cores and to do the new taping without getting on their knees and/or straining their backs.

We’ve designed the rewind shaft front supports to rotate downwardly rather than swing outwardly toward the operator (in fence-gate configuration). The main reason for this is to allow the addition of a rewind roll unloading aid or turnstile that allows the operator to slide finished rolls from the shaft to the turnstile without actually lifting the rolls. This also allows faster changeover of rolls (so there’s less downtime) while maintaining the relative location of the inspection, slitting and rewinding areas to get the major advantage of the Printrack processing and functional capability.