Successful “open-heart surgery”
Bielefeld – Schur Flexibles Moneta specializes in the production of sophisticated packaging made of extremely thin films and foils for the snack and candy industry. With a new register control system from BST eltromat International the plant is achieving outstanding quality on its gravure printing machines. Prior to this project, two gravure printing machines were successfully retrofitted with register control systems from BST eltromat at the Schur Flexibles Benelux plant in the Netherlands.
The Schur Flexibles Group covers the entire value chain and also operates its own pre-press stage, including the manufacture of gravure cylinders. The majority of the processed plastic films are also manufactured within the group. “Thanks to our special technology, we can print and convert ultra-thin plastic and aluminum films and foils, and paper as well. Significant savings in material consumption are possible thanks to the new register controller,” says Stefan Zoister, head of engineering at Schur Flexibles Holding GesmbH, based in Vienna, Austria.
“Schur Flexibles Moneta predominantly processes materials that are anything but commonplace in the gravure printing process, due to their special properties,” says Wolfgang Hasselbeck, director of operational excellence for the group, explaining the challenge for the register control and the need to keep it up to date. “The interplay between the gravure cylinder, doctor blade and impression cylinder is highly complex, and alongside the register control is the most decisive factor for quality.” The thinner the processed films and foils, the more flexible they are, and the more challenging it is to maintain the specified register tolerances when printing.
There was another good reason to convert the gravure printing machines to the latest register control systems: Increasing diversification in the candy industry has caused packaging batch sizes to shrink sharply in recent years. This means that the setup costs, including setup waste, take on increasing significance in the process as a whole. However, replacing register control systems in fully loaded gravure printing machines is no easy task. Such an operation is comparable to open heart surgery. Nevertheless, the Schur Flexibles Group decided to go this route in 2015. The starting point was retrofitting two gravure printing machines at its plant in Leek, Netherlands, with the regi_star 20 register control system from BST eltromat. This plant is the global market leader in tobacco pouches for “roll your own” cigarettes. One more gravure printing machine was retrofitted at Schur Flexibles Moneta in 2016. Here too, the existing register control was replaced with a state-of-the-art regi_star 20.
The profitability calculation presented by BST eltromat in 2014 suggested that the investments would quickly pay for themselves, and this was later confirmed in practice. Stefan Zoister: “In both plants, we were able to reduce our setup time, including start-up waste. This allows us to produce even small batch sizes for our customers efficiently.” In addition, the high-precision, innovative technology enables enhanced register control, delivering even higher quality for various products. “The sensor on the new register control reliably detects even weak contrasts. At the same time, the new control enables narrower register tolerances, and it can easily cope with all the challenges of everyday printing,” says Peter Lesny, head of operations at Schur Flexibles Moneta.
More reliability for critical products
Particularly for “critical” packaging materials, the high-precision register control has significantly increased production reliability. For the operator, it is now much easier to print them. Faulty material sections are reliably detected and subsequently cut out of the rolls in a targeted manner. As a result of this, the amount of waste produced during both the start-up of the gravure printing machine and ongoing production has been drastically reduced since the switch to the regi_star 20.
For Peter Lesny, the register control’s user-friendliness is also an important factor: “The regi_star 20 can be set up in just a few easy steps using the intuitive menu structure. After that, it adjusts the register quickly and reliably. You could compare this feature to an auto pilot.” During printing, the regi_star 20 shows the register marks in the form of live images on the touchscreen monitor. This means the machine operators can make sure that the print is in register with just a glance at the monitor. The regi_star 20 ensures this by checking whether the colors are accurately overlaid via high-resolution sensors behind every printing unit. If the measured values stray outside the tolerances, it automatically corrects the position of the gravure cylinders within a fraction of a second. This minimizes the amount of waste during ongoing production.
The regi_star 20 retrofit operation went precisely according to plan on all three machines, each of which is equipped with eight to eleven printing units. Production was restarted at the scheduled time for each machine. On Schur Flexibles Moneta’s gravure printing machine, the experts from BST eltromat replaced not only the register control but also parts of the drive technology. As a result, the machine now has servo drives for longitudinal register adjustment and an automated scanning-head tracking system. This means the scanning heads always move to the center of the register marks automatically, which further increases process reliability.
“The project team worked together excellently. The employees from Schur Flexibles performed all the necessary pre-assembly work perfectly. That allowed our technicians to work efficiently,” says Dieter Jochmann, product manager for register control systems at BST eltromat, in praise of the smooth commissioning process. “Our trust in the technology and reliability of BST eltromat is reflected in the fact that we completed the two retrofits in Leek in direct succession,” says Hasselbeck, looking back. There was a one-week “trial period” – no more time than that was planned between the retrofits. Many plants in the Schur Flexibles Group also use quality assurance systems from BST eltromat. Due to the many years of collaboration between the two companies, Schur Flexibles knew that it could trust BST eltromat to implement the projects successfully.
The new register controls also support the environmental goals of the Schur Flexibles Group – after all, less waste means more sustainability. “We also need high-precision technology in order to optimize the use of materials in the manufacture of packaging,” adds Stefan Zoister. Sustainability is a particularly important concern for the Schur Flexibles Group. In fact, it specializes in sustainable packaging solutions and was awarded the German Packaging Award 2018 in the “Sustainability” category, as well as the award in Gold for its recyclable FlexiClose(re).
“The new register controls will give us more flexibility in meeting customer requirements, with reproducible results over the long term,” says Zoister, highlighting the benefits of the innovative technology. The high degree of automation makes it easier for the gravure printing shops, which work around-the-clock, to produce consistent results.
Schur Flexibles Moneta
Schur Flexibles Moneta is based in Trebisov, southeast Slovakia, has 80 employees and is part of the Schur Flexibles Group’s Center of Excellence concept. The plant, which was founded in 2002 and taken over by the Schur Flexibles Group in 2014, is a globally unique converter that prints, laminates and coats extremely thin plastic and aluminum films and foils (up to 3 µm) and wax paper laminates using its outstanding technical equipment and specialized know-how. Around 90% of the products manufactured by Schur Flexibles Moneta are exported.
Peter Lesny, head of operations at Schur Flexibles Moneta (left), explains to Hubert Göppel, technical sales manager for register solutions at BST eltromat, what the machine operators at the plant particularly like about the intuitive menu structure on the touchscreen monitor of the regi_star_20 during their everyday work.