Focused on simplicity, eCon Sheeter appeals to factories of all sizes through intuitive HMI, multi-zone safety capabilities and remote access for tech support
Whether paperboard boxes contain tissues, toothpaste or taco shells, they must go through many steps to become brightly colored packages on store shelves. The number of manufacturers involved from shop to shelf increases complexity, so it is important for each company to simplify processes when possible. For BW Papersystems, this means building top quality sheeters that its customers use to unroll and cut massive reels of paper or paperboard. The machines must also reduce downtime for end users, who print as many as 20,000 sheets per hour then fold them into packages.
“A key feature of our products is sheet and stack quality,” says Jeff Gafner, senior vice president of engineering & service for BW Papersystems. “These criteria include edge quality and minimal dust and debris, which lead to more downtime due to frequent printer cleaning. Dimensional consistency and stack quality permit the highest possible feed rates with minimal jamming.”
With more than 50 years of industry experience, BW Papersystems has maintained its ability to deliver high quality machinery. The company, which was founded as Marquip in 1968, was purchased in 2000 by Barry-Wehmiller, an international network of companies based in St. Louis. BW Papersystems maintains its global headquarters in Phillips, Wisconsin, with additional manufacturing plants in Germany, Italy, Hungary and China. Although the company maintains a leadership position in the industry, it recognizes that the demand never ceases for systems that can balance higher performance with lower cost and increased functionality in user-friendly designs.
BW Papersystems took these factors into careful consideration while designing the eCon Sheeter. The machine processes reels of paper or paperboard at high speed for printers and packaging operations. A framework holding two reels stands at one end, and paper is fed through a dual decurler into the machine. A two-position slitting system slices the paper into sheets, which are then precisely stacked on a pallet using side jogging mechanisms to improve stack quality. The eCon measures roughly 63 feet (19.24 meters) long from the edge of the paper reel end to the end of the stacker, and the length increases to about 92 feet (28.1 meters) if a second framework is added to implement a four-reel setup. The machine supports paper reels up to 65 inches wide and 7,500 pounds. “The intention of this U.S.-built machine was to provide industry leading sheet and stack quality at a price that's competitive with imported machines,” says Gafner.
Balancing lower costs with greater functionality and support
Cost naturally factors into every new product, but BW Papersystems had an aggressive goal when the eCon Sheeter design process began in early 2013: The machine needed to cost 50% less than the legacy system it would replace. BW Papersystems has customers of all sizes, and while some larger companies might spend more for a feature-filled system, smaller companies often do not have that luxury. “An investment of this size is a significant portion of a small corporation’s capital expenditure spending, perhaps for many years,” Gafner says. “These smaller companies are interested in high quality production equipment for minimal capital investment.”
It was also important to create a design that showcased innovation and simplicity, according to Erik Paulson, project engineer for BW Papersystems. “Simplicity in terms of electrical design includes connectivity between the different components and the eventual replacement of components in the field. It also includes the ease of machine startup, such as downloading drive parameters once drives have been installed or replaced,” he says. This concern extended to simple HMI, especially for smaller facilities that likely do not employ a full-time electrical engineer. The eCon Sheeter HMI needed to support remote access so BW Papersystems engineers would be able to troubleshoot equipment without traveling to the site, which could also mean costly downtime for customers.
With cost and simplicity as strict requirements, the BW Papersystems team compared control system vendors using 30 criteria, including performance, cost, lead-time and availability of spare parts. Examining product lifecycle was important to ensure equipment would not soon become obsolete. The team sent specification documents that listed the machine component requirements to 11 vendors.
The finalists’ technical support and ability to supply preassembled control cabinets became deciding factors, according to Peter Forster, product manager of software and controls for BW Papersystems. “We expected assistance not only in selecting devices but also in panel layout and wiring best practices. The vendor also needed to provide support onsite for startup and testing of the first machines,” Forster says.
BW Papersystems had used Beckhoff controls devices in previous machine designs, but technological innovation and competitive pricing tipped the scale in favor of Beckhoff again for the eCon Sheeter project.
Cost-effective solutions deliver power, speed and safety
The final machine design delivers simplicity through the automation hardware and software implementation. A Beckhoff CP2907 multi-touch control panel displays the HMI, and any operator familiar with smartphone technology can easily learn how to use the compact 7-inch touchscreen. In addition, TwinCAT 3 automation software provides an intuitive, open platform solution that supports remote access and includes indispensable diagnostic tools, including Scope View. “We have the ability to monitor a multitude of signals, even in the 250-microsecond range, and display them using TwinCAT Scope View,” Paulson says. “We use Scope View frequently to troubleshoot problems or simply to tune the system, and I believe it is one of the biggest selling points of the TwinCAT software platform.”
From running the software to handling motion control for the multiple AX5000 servo drives, a CX2020 Embedded PC with a single-core 1.4 GHz Intel® Celeron® processor automates the entire machine. The ability to use one controller for PLC, motion control and HMI was a great improvement from previous machines that required hardware PLCs for each function. “Fewer parts typically means improved reliability, especially when motion control is involved,” Forster says. “Some of our older solutions used a separate motion controller and PLC, and we still struggle when those stop communicating. We have not experienced any of these problems with the Beckhoff PC-based control solution.”
Beckhoff supplied a completely assembled and tested control cabinet, which made commissioning more efficient. Paulson explains that high-density I/O terminals were crucial in the design: “We have little extra space on that rack, so without high density I/O hardware, we would have had to redesign the entire cabinet. The EtherCAT Terminal system from Beckhoff was a great space saver.”
An industrial Ethernet fieldbus that can communicate with 1,000 digital I/Os in 30 µs, EtherCAT enabled the system to communicate in real-time and provide extremely fast servo loops, ensuring that each device on the network offers high performance, precision and determinism.
Safety was also important for such a high-speed machine that operates large rollers and high-speed cutters. The eCon Sheeter features a comprehensive chain of e-stop buttons and safety sensors around the knife draw, roll cylinders, diverter and stacker lift, which features an anti-toe-crush perimeter. TwinSAFE Terminals integrated throughout the system architecture allow the machine to monitor all pinch points and cylinder hazards. “TwinSAFE programmable safety technology provides the status of each of those contacts to our user interface without any additional wiring,” Forster says. “We know the status of each function block, and we can display all that information to the user.”
Cutting cost and panel size in half makes the project whole
Beckhoff application engineers assisted BW Papersystems in the design and testing process at the northwoods Wisconsin facility. When the eCon Sheeter first shipped in January 2014, it exceeded every expectation for functionality, footprint and cost. Gafner explains that the final price achieved the aggressive decrease-in-cost goals from the legacy system it replaced: “The team hit the cost-reduction goal and shipped the initial machine on time. Collaborating with Beckhoff engineers on the systems design was a significant part of achieving this success.”
Even on a machine as large as the eCon Sheeter, it is important to reduce component count and footprint when possible. Compact EtherCAT I/O helped reduce panel size by 50% for some units and closer to 70% for others. The space-saving CX2020 Embedded PC also allows the machine to run a 30,000-line count encoder, which is a functional improvement over the legacy system. Combined with high-performance EtherCAT servo drives, TwinSAFE technology and the intuitive multi-touch HMI that can be accessed remotely using HTML5 technology, the end result offers simplicity without sacrificing innovation for end users.
“Simplicity doesn’t mean low tech,” Forster says. “It means that if an operator hits an E-stop and can’t reset the circuit, he can easily find the reason it will not reset using TwinCAT and EtherCAT rather than a stack of blueprints, a voltmeter and a whole lot of knowledge and wasted time. That’s one of the huge advantages of PC-based control from Beckhoff.”
The eCon Sheeter project produced an affordable machine with greater functionality that simplifies life for customers of BW Papersystems and their end user customers. However, it also simplified commissioning for the company by reducing installation times by 65% without any negative effects on performance.
“For us, that’s a home run,” Gafner says. “Certainly, having the Beckhoff support come to our facility in Phillips to work with the BW Papersystems team was significant. Going forward, we will rely on this type of strong relationship with all our key suppliers, especially Beckhoff, to help advance our next generation development projects.”
Are you interested in enhancing your new machine designs with PC-based automation? Contact your local Beckhoff sales engineer today.
James Figy is the Senior Content Specialist for Beckhoff Automation LLC.
A version of this article previously appeared in OEM Magazine.