Converters understand how many steps and purposeful decisions go into transforming rolls of film into bags and pouches. To ensure that the 760-SUP stand-up pouch system would continue to flexibly adapt to new requirements, U.S. machine builder CMD Corp. decided on a complete redesign.
With control technology from Beckhoff, they achieved 40% faster changeovers combined with 90% uptime and large performance reserves for the future.
While the earlier iterations of the 760-SUP stand-up pouch system were well received in the market, outdated machine control and networking were holding CMD back. The engineers had pushed the legacy platform to the limit, and it didn’t provide flexibility for further customization. That capability is important to ensure CMD lives up to its name, which is an acronym for Custom Machinery Design.
For more than 40 years, the Appleton, Wisconsin-based company has delivered custom-tailored converting and packaging equipment, aiming to provide their customers with unique competitive advantages.
Thus, the CMD engineering and product teams began working on a redesign of the 760-SUP in late-2021. Rather than make incremental adjustments, they decided to redesign the machine from the ground up. That meant many mechanical changes and a new control platform.
Scott Fuller, Product Line Manager, Intermittent Motion Products at CMD, explains the objectives: “The market is telling pouch machinery OEMs that their systems need to provide even faster changeovers and more intuitive operation – as well as less scrap.”
New room to move
“The first change we made to give converters an edge was ‘taking off the hood,’ so to speak,” Fuller says. Using light curtains instead of physical barriers supported an open design. Operators can step into the machine for changeovers, which is more user friendly, simplifies the identification of machine components and accelerates changeovers.
Second, the company focused on the actual sealing technology. Bag or pouch converting machines typically fold material the same way, but sealing requires many different specifications for each film and process.
“Our sealing and zipper crush technologies support high-performance handling of legacy films,” Scott Fuller says. “But this stand-up pouch machine delivers advanced capabilities for emerging recyclable pouch materials and new digital printing methods.”
These design changes also required automation technology with enough power and speed to ensure high-quality, repeatable operation as well as flexibility for the future. CMD evaluated new automation platforms and, in the end, selected EtherCAT and PC-based automation from Beckhoff for the next-generation 760-SUP.
New performance reserves
CMD worked closely with Beckhoff’s local engineering team on the 760-SUP redesign. Beckhoff Regional Sales Manager Don Seichter, Applications Engineer Dave Ross and General Technical Support Rob Lecheler assisted in specifying components and providing support while migrating to TwinCAT 3 automation software.
“CMD already had a firm foundation of engineering expertise,” Dave Ross says. “That allowed them to rapidly move from their previous platform to Beckhoff. For example, they already used object-oriented programming (OOP) paradigms, which sped up conversion of existing code.”
TwinCAT provides an end-to-end engineering and runtime environment for all aspects of machine control from PLC to IoT. Integrated into Microsoft Visual Studio, TwinCAT empowers engineers to program in the right language for their application. TwinCAT Scope, Drive Manager 2 and other pieces of the software toolkit also enhanced CMD’s capabilities in design and commissioning.
The TwinCAT runtime is on a CX2033 Embedded PC from Beckhoff. Backed by a Beckhoff uninterruptible power supply (UPS), the CX2033 serves as the sole machine controller for the 760-SUP.
A dual-core AMD Ryzen™ processor supplies ample performance, according to Jason Plutz, electrical engineer at CMD: “We’re running at about 15% CPU load on just one of the controller’s two cores. We’re scanning extremely quickly with the CX2033, and we could run it even faster. I’ve never seen performance like this with previous controllers.”
Fast and safe control with EtherCAT
The 760-SUP machine features a continuous motion section for feeding and folding film as well as an intermittent motion section for sealing and zipper crush. In the past, a gusset punch on the continuous side required additional hardware and excessive engineering efforts to synchronize actuation with the material position.
Here, EtherCAT further boosted performance. “EtherCAT’s speed, combined with deterministic control and an encoder module from Beckhoff, seamlessly incorporated the incoming material position and punch with standard I/O modules,” Don Seichter from Beckhoff says. “The Beckhoff solution just worked to reduce complexity.”
EL3314 and EL3318 analog input terminals enable compact, direct connection of thermocouples for accurate temperature control of the sealer bars. Another space-saving technology, the EK1914 EtherCAT Coupler offers standard digital inputs and outputs alongside two safe inputs and two safe outputs, all built in.
This means CMD can distribute a small amount of TwinSAFE I/Os with integrated functional safety capabilities on each tool in the machine line. TwinSAFE also allowed CMD to easily incorporate the necessary light curtains, E-stops and other safety devices to protect operators while maintaining an open machine design.
“On our previous design, we had to run cabling from each tool back to a standalone safety system. TwinSAFE really cleaned that up,” Jason Plutz says.
The high synchronization of EtherCAT extends to motion-intensive applications, and provided an edge in combination with the AX8000 multi-axis servo system and various AM8000 servomotor solutions. “These servo technologies offered incredible performance with high-resolution feedback in a space-saving design,” says Plutz.
Repeatability and high performance
Before film materials make it to CMD’s machines at converting facilities, they must undergo extrusion, printing and lamination. So waste material is at its most expensive point at that time, Scott Fuller from CMD explains.
But less waste through high accuracy is not the only way to improve machine efficiency. The CMD engineers remain cognizant of setup time and downtime.
Switching to the Beckhoff platform reduced test and debug times for the CMD developers by several weeks. EtherCAT accelerated commissioning by scanning in all devices on the network. Use of Drive Manager 2 reduced the time needed to tune motors by a factor of three. The Beckhoff technologies ensured precise, repeatable motion control for the zipper crush.
The safe, open machine design enabled by TwinSAFE led to 40% faster changeovers than competitive machines. Altogether, the redesigned system ensures high throughput with uptime rates higher than 90%, according to CMD customers.
All these changes led to better, faster Return on Investment rates for end users. To illustrate this, CMD has an ROI calculator on its website showing the details.
Beyond that, PC-based automation technology and EtherCAT leave CMD room to grow with its customers. CMD intends to leverage the inherent connectivity of PC-based control to implement edge computing and IoT functionality in the future. And moving forward, CMD plans to migrate even more of its machine lines to Beckhoff.
Beckhoff Automation
Tel. +27 11 795 2898
info@beckhoff.co.za
https://www.beckhoff.com
