Successful “open heart surgeries”
Why Schur Flexibles has retrofitted its gravure printing machines with the latest register controls from BST eltromat
The Schur Flexibles Moneta plant in southeast Slovakia specializes in the production of sophisticated packaging made of extremely thin films and foils. With a new register control 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 plant in Benelux (Netherlands).
“Schur Flexibles Moneta predominantly processes materials that are anything but commonplace in the gravure printing process, due to their special properties,” explains Director of Operational Excellence Wolfgang Hasselbeck, who gives us a tour of the plant in Trebisov. We watch as two gravure printing machines print ultra-thin films in the highest quality. Rolls of film printed with extremely complex designs are waiting to be transported out of the printing room for further processing. This plant, Hasselbeck explains, has unique capabilities. The site excels in high-quality, sustainable packaging for the snack and sweets industry.
Product development as a key factor for success
“Our production facilities allow us to manufacture high-grade finished packaging made of ultra-thin plastic films and aluminum foils, as well as paper,” says Stefan Zoister, outlining the position of the corporate group on the market. Zoister is head of engineering at Schur Flexibles Holding GesmbH, based in Vienna, Austria.
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 ultra-thin films and perform additional conversion. This enables considerable savings in material consumption,” Zoister adds.
Open heart surgery
“The interplay between the gravure cylinder, doctor blade and impression cylinder is highly complex, and together with the register control, it’s the most decisive factor for quality,” remarks Hasselbeck, emphasizing the need to keep this technology up to date. The thinner the processed films, the more flexible they are, and the more challenging it is to maintain the specified register tolerances when printing.
“Today’s sweets industry is more diversified than ever. As a result, the batch sizes of packagings has shrunk considerably in recent years. This means that the setup costs, including setup rejects, take on increasing significance in the process as a whole,” explains Hasselbeck.
Changing the register control in gravure printing machines working at full capacity 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 the group’s plant in Leek in the Netherlands with the regi_star 20 register control from BST eltromat. This plant is the world market leader in tobacco pouches for “roll your own” cigarettes. At Schur Flexibles Moneta, one more gravure printing machine was retrofitted in 2016. Here too, the existing register control was replaced with a state-of-the-art regi_star 20.
Production responsive to market needs
“In 2014, BST eltromat provided us with a profitability calculation that predicted this investment would soon pay for itself. We used this data in our internal calculations. There, the numbers were confirmed – just as they were later in practice,” says Zoister in summary. “In both plants, we were able to reduce our setup costs, including start-up waste. This allows us to efficiently produce even small batch sizes for our customers.”
In addition, the high-precision, innovative technology enables enhanced register control, delivering even higher quality for various products. “The sensor of 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 plant, it is now much easier to print these materials. Faulty material sections are reliably detected, and they can be cut out of the rolls later. As a result, the amount of waste has been drastically reduced since the switch to the regi_star 20, not only during the start-up of the gravure printing machine, but also during ongoing production.
From Lesny’s point of view, Schur Flexibles Moneta also has the user-friendliness of the new register control to thank for the increased performance in gravure printing. “The regi_star 20 is quick and easy to set up,” says Lesny, referring to the clearly laid-out touch monitor of the register control. This is integrated into the control center of the retrofitted gravure printing machine. “Our machine operators configure the register control in a few steps with the intuitive menu structure. After that, the regi_star 20 quickly and reliably adjusts the register. 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 touch monitor. This means the machine operators can make sure, at a glance, that the print is in register and kept stable by the regi_star 20. 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, the register control automatically corrects the position of the gravure cylinders within a fraction of a second. This minimizes the amount of waste during ongoing production.
“The quality requirements for packaging are defined in part by consumers. In addition, there are legal requirements, which include shock images in the tobacco industry, which require maximum detail and precision in reproduction,” explains Hasselbeck. This work was performed with the new register control at the Schur Flexibles Benelux plant. The Schur Flexibles Group is a provider of all conventional print methods in the highest product quality.
“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.
The retrofit to the regi_star 20 register control from BST eltromat went precisely according to plan on all three machines – equipped with six to eleven printing units. Production was restarted at the scheduled time in each case. On Schur Flexibles Moneta’s gravure printing machine, the experts from BST eltromat not only replaced 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 very effectively. 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. The project team defined the objectives and expectations for the retrofit in advance. The machine operators were familiarized with the new possibilities and user-friendly operation of the new register control at the BST eltromat training center in Leopoldshöhe, Germany. All of this contributed to successful outcomes in the retrofitting projects. “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.
At Schur Flexibles Moneta, in particular, some fine-tuning was done in the weeks after the retrofit, due to the special materials that pass through the gravure printing machine in this case. “Employees on both sides pulled together to ensure the successful implementation of every detail from start to finish,” says Hasselbeck. Many plants in the Schur Flexibles Group also use quality assurance systems from BST eltromat. In view of many years’ cooperation, the company already knew that it could rely on the quality and successful implementation of the projects.
Environmental aspects of the investment
The new register controls also support the environmental goals of the Schur Flexibles Group – as less waste means more sustainability. “We also need high-precision technology in order to work with thinner films in our production of packaging,” adds Zoister. This allowed for the optimization of material consumption.
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).
Schur Flexibles Moneta
Schur Flexibles Moneta, with 80 employees in Trebisov in southeast Slovakia, is part of the Center of Excellence concept of the Schur Flexibles Group. 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 foils (up to 3 µm) and wax paper laminates with its outstanding technical equipment and specialized know-how. Around 90% of the products manufactured by Schur Flexibles Moneta are exported.