For more than 40 years, Appleton, Wisconsin-based CMD has delivered flexible, high-speed converting and packaging equipment. CMD machines produce nearly every drawstring trash bag produced in the U.S., with international market share growing rapidly. CMD also offers solutions to industries like renewable energy.

This broad portfolio harnesses technologies to save time and cut costs. With a proven track record of tailored solutions, CMD lives up to its name, which is an acronym for Custom Machinery Design.

Making impactful changes requires flexible automation technology, according to Scott Fuller, Product Line Manager, Intermittent Motion Products at CMD Corp.

“Every converter is looking for an edge,’” Fuller says. “When we get customer requests that are twists to the established process, our technology needs to rise to the challenge.”

Like its converter customers, CMD stays on the lookout for new technologies that provide the machine builder with unique competitive advantages. While the earlier iterations of the 760-SUP stand-up pouch system were well received in the market, CMD thrives on continued innovation. This is clear from the numerous patents displayed throughout the CMD Technology Center.

Outdated machine control and networking were holding CMD back as they had pushed the legacy platform to the limit. Increasing controller performance levels multiplied costs, and the technologies were too rigid and difficult to adapt to custom requests.

The CMD engineering and product teams began working on a redesign of the 760-SUP in late 2021. They aimed to solve these performance limitations and complete the machine as their main booth highlight at PACK EXPO International 2022. 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.

The design highlights how CMD skillfully implemented customer feedback and market research.

“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,” Fuller said.

Standing up to motion control limitations

“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 and simplifies the identification of components.

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,” Fuller says. “But the stand-up pouch machine delivers advanced capabilities for emerging recyclable pouch materials and new digital printing methods.”

Both design changes led to better, faster ROI for end users. To illustrate this, CMD has an ROI calculator on its website to show the details. The design changes also required automation technology with enough power and speed to ensure high-quality, repeatable operation as well as flexibility so converters can continue refining their processes in the future.

Meeting these technical requirements was critical as CMD evaluated new automation platforms. Cost and support capabilities from the automation vendor also played decisive roles, according to CMD Electrical Engineer Jason Plutz.

In the end, CMD selected EtherCAT and PC-based automation from Beckhoff for the next-generation 760-SUP. “Not only was Beckhoff less expensive in our application, but also the technology was a major leap ahead,” Plutz says. “We made bigger advances than we had hoped.”

Drive safe – and drive fast with EtherCAT 

The 706-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, the EtherCAT industrial Ethernet system 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,” Beckhoff Regional Sales Manager Don Seichter noted.

Repeatability and high performance are in the bag

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.

Fuller explains: “We pay close attention to scrap and the process itself, so our customers can be confident in their pouches before they get to the CPG.” But that’s not the only waste they try to eliminate. The CMD engineers remain cognizant of setup time and downtime.

Switching to Beckhoff’s New Automation Technology platform reduced test and debug times 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, along with more intuitive operation and changeovers. The safe, open machine design enabled by TwinSAFE led to 40% faster changeovers than competitive machines. All together, the redesigned system ensures high throughput with uptime rates higher than 90%, according to CMD customers.

Moving forward, CMD plans to migrate even more of its machine lines to Beckhoff.

“With their automation technologies, the future looks clearer for us,” Fuller says. “We don’t face the same limitations of previous control systems. Beckhoff allows us to choose what we need as we develop our machines. We now have a superior automation platform, and our customers can keep looking to CMD for that competitive edge.”