Towards zero-defect production with quality assurance systems from the BST Group
Nyquist Systems, manufacturer of inspection systems for narrow web printing processes, brought this system to the market as an alternative to conventional stroboscopic lamps. Since then, the Barthel Group, which specialises in the production of self-adhesive labels of various designs for a number of sectors, has been following every step in the development of the TubeScan systems. Several of its machines are now equipped with these systems for 100% inspection in printing and packaging. Nyquist Systems has been part of the BST Group since the beginning of 2019. The group is responsible for the sales and service of the TubeScan portfolio worldwide.
One to twelve-colour labels, premium labels, multi-layer labels, wine labels, wraparound labels, (re-)sealing labels and blank labels – with a total of six companies, the group covers a wide range of products and services, and is at home in many markets. Its main focus is on food, wine and spirits, home care, cosmetics and pharmaceuticals, as well as the chemical and automotive sectors.
Barthel GmbH has been using 100% inspection systems in finishing since 2003. The first solution was a conventional camera system. In the years that followed, the label printing company kept its machinery up to date by gradually installing line scan cameras for 100% inspection. The new TubeScan digital strobe from Nyquist Systems with its attractive price/performance ratio emerged as an alternative to these cameras in 2013.
“We wanted to test the quality, handling, and reliability of this system, which offered great value for money, as an alternative to line scan cameras in day-to-day operation,” says Mischa Barthel, managing director of the Barthel Group, explaining why his company installed the world's first digital strobe. “The first TubeScan was really more of a solution for missing label inspection. But even back then, we recognised its potential. It was only a matter of time before its area scan camera would reach a higher resolution and thus offer better image quality. Also, Nyquist Systems managing director Dr Stephan Krebs assured us at the time that the TubeScan would continue to evolve in the direction of 100% inspection.”
Continuous development of quality and functionality
In the years that followed, the fast-growing company gradually had more and more TubeScan systems installed in its printing presses. As time went on, more and more of these became higher-quality devices that were able to detect print-related defects. “The new TubeScan systems helped our employees satisfy the rising quality requirements of the market,” says Friedhelm Schmitz, head of Quality Assurance.
Over the years, the focus has shifted from detecting the most important defects in the label rolls that have already been produced to preventing printing errors that would lead to waste. This was primarily possible due to the increasing resolution of the matrix cameras in the systems. With their high 4k resolution, the latest area scan cameras have largely caught up with the 100% image reproduction quality found in line scan cameras. In fact, the entire TubeScan portfolio now has access to comparatively inexpensive 9-megapixel area scan cameras made in Germany. The cameras reach resolutions of 83µm or 100µm in label printing with web widths of 330mm to 430mm, and even resolutions of 55µm for special applications. However, Nyquist Systems has also continuously expanded the functionality of the software, the real-time visualisation options and the inspection and measurement process, including lighting options.
Barthel: “With the visualisation of printing defects in our packaging production, we’ve been able to avoid the reputational damage that would have inevitably resulted from deliveries of imperfect labels to our customers. With 100% inspection in printing, we’re minimising our waste. Our printers can see immediately if defects are emerging and take action to remedy them. We produce the desired quality in a more deliberate manner and, thanks to the counters integrated into the TubeScan systems, we make the precise quantities of labels required.” Both these factors have increased the productivity and profitability of the company’s label manufacturing.
Almost half of the group’s 35 printing presses are now equipped with TubeScan systems. In addition, these systems are now used in several packaging machines for final inspection. Thus, in large areas of the company’s production process, quality is now inspected in two steps. This double assurance guarantees uncompromising zero-defect production. There are no costly complaints.
Currently, Barthel is considering equipping all its presses with 100% inspection – the next step being the nine digital presses, which mainly produce shorter runs and custom labels. Schmitz: “It’s important to keep the machine operators on board and show them the benefits of innovative quality assurance. One example of this is that the TubeScan systems offer them a more relaxed way of printing that still maintains the required level of quality.” The printers should be able to monitor themselves and retrieve documentation on quality from the systems. There are still occasional surprises when machine operators find defects using the systems that they would not have found otherwise.
Are the registers right? Are the texts and barcodes being printed correctly? Are there any stains on the labels? Are the spaces between the labels correct, and are the labels centered? The TubeScan systems offer the company a wide range of options in terms of 100% inspection. “The systems can be flexibly configured for specific orders. In other words, they reliably detect all the printing and finishing defects within the specified parameters that customers wouldn’t accept,” explains Schmitz. At the same time, the group can optimise the performance of its machines despite the 100% inspection.
In the near future, the group will be able to make work even easier for its printers thanks to the new PDF comparison option available directly within the printing presses, and further reduce setup times. With this new function, the machine operators will be able to ensure that their machines will produce impeccable quality from the get-go before printing has even begun. “Manual comparison of the printed labels with the PDF files from the pre-press stage is still a bottleneck in our predominantly three-shift production. The PDF comparison directly in the printing machines eliminates the need for our printers to scan proofs and compare them with the specifications from the pre-press stage. Printing will get faster,” says Schmitz of the benefits. In addition, 2019 will see the Barthel Group putting a digital text inspection system into operation in one machine for the first time, before possibly integrating it into other machines at a later date. A further option is to connect the TubeScan systems in the printing and finishing machines. If information flows directly from printing to finishing, waste can be further minimised and the quality produced clearly documented.
In addition to digital stroboscopes, the company also uses other systems from BST eltromat. Barthel: “I’m pleased with the level of quality assurance we’ve reached today. With future innovations, we’ll doubtlessly be able to improve our results even further.”www.bst.group