Baumer hhs, a leading manufacturer of industrial glue application and quality assurance solutions, has launched Xact Easyfold system that enables users to meet very close tolerances in folding-gluing operations on multi-point gluers, even when processing the most demanding materials.

According to the company, the high-dimensional accuracy achievable with this efficient water scoring solution, even with complex folding and gluing, benefits the entire process chain, but especially filling and packing.

“Increasingly stiff substrates are being processed today on multi-point gluers, and the variety is virtually endless. As a result, precision has become an even greater challenge in the folder-gluer process. At the same time, error tolerance is shrinking because brand owners are placing rising demands on the quality of their packaging and will continue to do so. With the high-end technology behind our Easyfold system, packaging manufacturers can reduce bending stiffness along score lines and temporarily increase elasticity. Their multi-point gluers can then execute consistent folds with virtually no force – and without affecting the surface quality of the materials they process for customers,” said Thomas Walther, head of corporate strategy & innovation at Baumer hhs.

Process reliability

Baumer said a core component of the water scoring solution is the SW-600 Easyfold precision applicator. Developed specifically for this application, it boasts very high reliability. A two-stage filter assembly effectively prevents the nozzles from clogging, including nozzles of very small diameter. Seals minimize the risk of drip formation even after extended periods in operation. These features also benefit the reliability of the overall process. Given its compact dimensions, the SW-600 Easyfold applicator can be installed even in confined spaces in multi-point gluers and folder-gluers.

The folding liquid is supplied to the system by a pressure-regulated feed unit with a variable working range of 1 to 5 bar. With such a control range, application of the folding liquid can be calibrated to the machine speed and volume of liquid required.

The Xact Easyfold controller connects the two components into a compact water scoring solution capable of operating up to four SW-600 Easyfold applicators. Any number of different application patterns can be set up easily and quickly on the controller. “With all of these features, our Easyfold water scoring solution can be integrated in various machine configurations to suit the existing process,” said Walther.

Precision glued joints

To reduce the bending stiffness of packaging materials, the SW-600 Easyfold precision applicator applies very narrow streams of scoring fluid along the edge of fold lines. At low machine speeds, it can optionally apply dotted lines to avoid excessive wetting.

The scoring fluid consists of water with an added surfactant, which reduces the surface tension of the packaging material along the edge of fold lines.

Instead of just remaining on the surface, the liquid can immediately penetrate the fibers of the substrate, significantly reducing bending stiffness in a defined area – but only temporarily. The multi-point gluer or folder-gluer can then precisely fold a carton along the wetted lines, adhering to even the tightest dimensions.

In many cases, this method even enhances the appearance of a packaging product, especially if it is made from dry, brittle material with low elasticity. In the folding process, a lack of elasticity can cause cracking on the surface of a packaging material, but this too can be avoided with water scoring.

“With our Easyfold system, customers can avoid asymmetrical folds, which cause deviations in the inner and outer dimensions of the packaging. This issue often causes problems in the filling process, particularly when thin materials and close tolerances are involved. Under some circumstances, it can even make packaging unusable. Both cases lead to complaints that are not only costly for packaging manufacturers, but also outmoded in view of today’s sustainability concerns”, Walther said.

Customer loyalty

Because water scoring reduces the spring-back forces of the glue flaps, packaging manufacturers can also use it to optimize adhesive consumption.

“The folding liquid does not impair the stability of finished boxes in any way. We have verified this in studies, and our customers have confirmed it. Strength is reduced locally and only temporarily because the liquid penetrates the packaging materials uniformly and dries quickly. Absolutely no delamination has been observed to date in corrugated cardboard.”

“We invite customers and anyone interested in this technology to visit our hhs solution-center in Krefeld, Germany, where they can test our Xact Easyfold water scoring system on their own original packaging materials,” Walther said.