Krefeld – MLT-STA is the name of a new system from Baumer hhs for cost-efficiently glue detection on flexo folder gluers. Based on proven technology and available as a stand-alone detection system, the MLT-STA was engineered specifically for manufacturers of corrugated box packaging who until now have gone without monitoring glue application. The MLT-STA works in combination with any existing glue extrusion system available on the market.

This low-cost detection system is easy and convenient to set up and operate via touch screen. With integrated optical MLT-40 multi-bead cold glue sensors from Baumer hhs. The MLT-STA can check up to three glue beads on one or two sides. The MLT-40 sensors are in use for glue detection around the world for all kinds of corrugated board processors and have proven to be highly reliable in day-to-day production.

The MLT-40 sensor checks in fractions of a second whether glue was applied in the right spots on the glue flaps and that glue beads are not extended. It also checks compliance with prescribed distances from the edge of the glue flaps (edge detection), so that no glue oozes out when a box is folded. If the MLT-40 detects any deviations from target specifications, it immediately sounds an alarm, alerting the machine operator with both acoustic and visual signals. The MLT-STA then automatically marks faulty corrugated boxes with a UV liquid, making it easy for machine operators to identify and remove them at the ejecting unit of the flexo folder gluer.

“Worldwide, a lot of the older flexo folder gluers in particular are still equipped with capacitive sensors for glue or moisture detection. These devices are very sensitive to the fluctuating moisture content in the corrugated board, which is why they tend to operate unreliably and therefore are not really suited to processing corrugated boxes. They often are switched off in practice as a result, meaning that these folding box manufacturers are going without checking glue application. In view of the rising global demands on the quality of corrugated boxes, this is an untenable situation for manufacturers. With the MLT-STA, we have now developed an economical solution that fills this gap and can be retrofitted in flexo folder gluers without any major expense or effort. Because our MLT-40 is an optical sensor, it is

impervious to fluctuating moisture content in the sheets of corrugated board,” says Andreas Schneiders, Technical Sales Manager Corrugated at Baumer hhs, explaining the benefits of the new system.

The MLT-STA generates reports in PDF format for every job, which corrugated board processors can use to document the quality of their production systems to their customers. What is more, measured values can be exported to Excel in CSV files to conduct statistical analyses and optimise the productivity of a flexo folder gluer.