Taking Quality Assurance to a New Level

10.05.2016

Shrinkflex’s new WRP-MV 10-color gravure printing press from Worldly is equipped with the latest technology from BST eltromat for register control, digital web monitoring, and 100% print inspection. Regi_star 20 impresses users with the information content of the real-time, live production images displayed on the machine operator’s monitor. The intelligent regi_star 20 sensor detects even the faintest contrasts on printed film packaging, such as those particularly encountered when dealing with cold seal and lacquers. The high-performance line scan cameras from iPQ-Check deliver detailed color image data across the entire print format, and log the production results. iPQ-View is a powerful tool that offers a wide variety of standard functions and optional features for digital web monitoring, including simple, instant defect diagnosis in the printing process. The web runs through the 10-color gravure printing press at a speed of 230 m/min.

Taking Quality Assurance to a New Level with BST eltromat Systems

How Shrinkflex Meets the Requirements of Its Demanding Customers More Reliably Than Ever

In the context of investing in a new 10-color gravure printing press from Worldly, packaging manufacturer Shrinkflex Co., Ltd. (Thailand) decided to equip it with a high-end register control system and high-performance inspection technology from BST eltromat. Both for Shrinkflex and for Worldly, their cooperation with the German manufacturer is a premiere – and the start of a new partnership at the same time.

Oishi, Cosmos, CP Meiji, Kao, Mistine, BiO Manufacturing, and numerous other names familiar in Thailand and the whole of Southeast Asia – the client list of Shrinkflex Co., Ltd. (Thailand), based in Bang Pakong in the direct vicinity of Bangkok, is a who’s who of the region’s branded goods industry. Established in 2007 and specializing in gravure printing, the company currently has a staff of roughly 250 employees and is the leading local manufacturer of shrink labels for branded goods.

Consistently Opting for Innovative Technologies

“We can only proactively cover the constantly growing quality requirements of our clients if we fully exploit today’s technical capabilities in quality assurance as well,” says Michael Tsoi, founder and owner of Shrinkflex Thailand. “That’s why we asked Worldly to equip our new WRP-MV 10-color gravure printing press with the latest technology from BST eltromat for register control, digital web monitoring, and 100% print inspection.” That was a premiere for Shrinkflex, as the company had previously always used quality assurance systems from other manufacturers.

Shrinkflex took PackPrint 2013 at the Bangkok International Trade and Exhibition Centre (BITEC) as an opportunity to carefully examine the offers of the various suppliers of corresponding technologies. “The decision came out clearly in favor of 100% inspection with iPQ-Check and digital web monitoring with iPQ-View from BST eltromat,” reports Michael Tsoi. He says the same applied to regi_star 20, once the responsible decision-makers at Shrinkflex had seen a presentation of this register control system’s capabilities – achieving rapid registration and maintaining register during the production process with a high degree of automation.

Offering Clients New Possibilities

“What impressed us most about regi_star 20 was the high performance of the intelligent RGB sensor and the information content of the real-time, live production images displayed on the machine operator’s monitor,” says Klive Lai, junior boss of Worldly Industrial Co., Ltd., from Taichung City in Taiwan, recalling a visit by experts from BST eltromat International to his company. The cooperation with this manufacturer is a premiere for Worldly, too.

Like no other register control system, the regi_star 20 sensor detects even the faintest contrasts on printed film packaging, such as are particularly encountered when dealing with cold seal and lacquers. The 1-pixel color camera of regi_star 20 also reliably “sees” very low-contrast marks, displaying them on the operator’s monitor in the form of live color images. Consequently, even these print marks can be unequivocally assigned, and the settings precisely adjusted without interrupting production. So, the days are gone when machine operators occasionally found it hard to ascertain whether they had selected the right print marks for register control.

“In turn, it was the high defect-detection performance of iPQ-Check and the unique image quality of iPQ-View that convinced us,” says Klive Lai. On top of which, the individual systems of the modular, network-based Increasing Productivity and Quality Center (iPQ-Center) solution for quality assurance in web printing feature a standard, intuitive, multi-touch user interface and thus offer great operational convenience. Thus, the highly convenient gesture control familiar from smartphones gives the machine operators central access to all functions – including zooming and selecting any desired image areas.

“With the solutions from BST eltromat, we give our customers better opportunities than ever for reliably meeting the quality requirements of their clients – and for easily and completely documenting the fact,” says his father and Worldly CEO Fu-Lai Lai, summing up how his company benefits from the recently begun partnership with the German full-line supplier. Against this backdrop, he said that Worldly also greatly welcomed the establishment of BST eltromat South East Asia Co. Ltd. in Bangkok, effective October 1, 2015. It was very useful to have a local point of contact with competent partners to handle the further customer projects that had been jointly launched in the meantime.

Rapid Job Changes and Less Waste

The new gravure printing press, including the innovative quality assurance systems, was delivered to the ultra-modern Shrinkflex facility in Bang Pakong in mid-February 2015 and put into service in the weeks that followed. “With regi_star 20, it now only takes about half a minute to set up the register control system, including presetting of the register rollers, the lateral cylinder position, and the mark positions. At the same time, we have about 200 meters less start-up waste per job in comparison with other register control systems,” says Mucharin Buahorm, indicating decisive improvements resulting from the new technology. As QA/QC Manager at Shrinkflex, she is ultimately responsible for the satisfaction of the ISO-certified company’s clients.

She says Shrinkflex partly owes this to the fact that the automatic scanning technology of the regi_star 20 register mark sensor perfectly supports BST eltromat’s single-head measuring procedure. This unique technology permits not only sequential control for a rapid production start, but also key color control for optimum production quality. If the machine operators select sequential control during setup – i.e. always using the preceding mark as the reference – the register control system automatically switches to fixed and sequential measurement at the start of production. That means convenient setup and guaranteed quality in packaging production.

“At the same time, the rapid defect detection and the great operating convenience of the iPQ systems enable the machine operators to react very quickly,” says Mucharin Buahorm, adding two further aspects. She says the significant reduction in waste is a key factor for profitability, especially in the case of jobs with tight budgets.

Production to European Quality Standards

The walk to the new 10-color gravure printing press first leads through a shop where Shrinkflex has installed various postpress systems. Even there, everything already looks very clean and tidy. We quickly pass through this shop and then enter the spacious, brightly lit pressroom, where the WRP-MV has been operating since spring 2015.

The first thing that catches our eye is the rewind unit of the gravure printing press. A few steps farther, and we can already see the multi-touch monitor of the digital web monitoring system. And then comes the traverse of this quality assurance system, which is integrated in the web, driven by an electric motor, and bears a high-resolution digital camera whose high-performance flash optimally and uniformly illuminates the entire printing area. On the printing units, in turn, we are struck by the register mark sensors and the professionally installed fiber-optic leads of the register control system.

The machine is just being set up for a job in which shrink labels for a fruit juice are to be manufactured. The machine operators have an impressively fast, established routine for setting up the register control system and the BST eltromat quality assurance systems integrated into a single solution. The entire machine is ready to go in next to no time, and production begins. The WRP-MV reaches its maximum printing speed of 230 m/min just a few moments later. That kind of performance is no real challenge, either for regi_star 20 or for iPQ-View or iPQ-Check; all these systems would work just as reliably at four times the speed.

Real-Time Quality Control

The monitor of the digital web monitoring system displays real-time, live images of the shrink labels just being manufactured. Their design shows a drawing of a split watermelon with Thai characters in the colors typical of that fruit – red and green. The split-screen display of iPQ-View compares the current, live production images with a reference image. Time and again, the machine operators switch back and forth between the full printing format and detailed views. They have previously programmed the individual camera positions in the control system and can now simply retrieve them at the push of a button. Moreover, there are various optical zoom variants that enable the machine operators to vary the field of view without any loss of display quality.

The iPQ-Check monitor likewise displays live images. The high-performance 4K RGB line scan cameras of this inspection system provide very high-resolution visualization of the quality of the printing on the shrink labels just being manufactured – and they do so completely, over the entire printing format. As with iPQ-View, the machine operators compare the live images with a reference image of the fruit juice shrink label. They can intervene in the process immediately to correct even the slightest deviations before they cause waste. Intelligent defect classification enables machine operators to distinguish between process-related and sporadic defects. And, of course, all deviations from the reference values are also displayed in diagrams and in the form of statistics.

The high performance of these quality control systems is partly due to the special camera link, which permits extremely rapid data transport in image processing. At the same time, the information is visualized on the monitors at a very high pixel rate.

Numerous Options for Quality Control

For Shrinkflex, another clear benefit of the innovative quality control systems is their flexibility in regard to substrates. It doesn’t matter whether the materials are opaque, transparent, translucent, or reflective. The intelligence of the algorithms guarantees maximum production reliability, even when dealing with highly reflective materials and holograms. For example, the sub-pixel algorithms of iPQ-View reliably detect reflections on the moving webs, even in the presence of different contrasts.

In addition to this, BST eltromat offers various visual lighting options to meet virtually any conceivable requirement, ensuring reliable illumination of the printed images on the different individual substrates.

Professional Documentation of Production Results

Also very convenient from the point of view of Shrinkflex are the options for completely documenting the stability of the quality achieved during production and exporting the results from the BST eltromat systems in XML format. All detected defects are recorded. For instance, iPQ-Check documents the first and last image of every defect, as well as the image of the greatest defect. If it comes to the crunch, all of this facilitates communication with the customer.

The innovative technology from BST eltromat has been received very well, including in the pressroom. If they had their way, the machine operators would also like to see the older gravure printing presses at Shrinkflex converted to the new systems. “The new technology enables us to meet the quality requirements of our customers better than ever before. At the same time, our staff working in the pressroom has far less stress,” says automation expert Michael Tsoi, summing up the progress brought about by the innovative web guiding and inspection systems. And not only does Shrinkflex carry out its production on Worldly machines, but Michael Tsoi is also the representative of the Taiwanese press manufacturer in Thailand. This means that many potential users from the region will get the opportunity to see the BST eltromat technologies for register control, digital web monitoring, and 100% print inspection that have now been installed on a gravure printing press from Worldly for the first time – live and working under real production conditions in normal operation.