A Handle on Better Packaging

By Jim Montague, Executive Editor

If a machine builder wants to remain competitive in a global market, then updating controls, motion, data processing, software and/or networking functions to provide more flexibility, improved speed and reduced costs is a necessity at some point.

PakTech (www.paktech-opi.com) in Eugene, Ore., manufactures handles that bundle two to 12 containers or large single bottles, and builds the machines that apply its handles at high speeds. The company started when founder Jim Borg designed the TwinPak handle in 1992 to accommodate a pair of gallon-sized milk containers. Besides bundling beverage bottles, spray bottles, lawn fertilizer containers and personal care products, PakTech also integrates its systems with those of container manufacturers to add handles to their own products before filling.

“Offering a machine with better speed wouldn't win orders—it also had to be affordable. We needed to bring down our controls costs to find a better balance of performance and price.”

These days, PakTech also offers some hard-to-find in-house products and services such as part design and engineering, mold development, injection mold manufacturing, UPC label application, and design, manufacture and servicing of inline application equipment.

PakTech usually starts a new project when a customer requires a new type of multi-pack handle. Its staff first gets a clear idea of the project, develops a 3D image within a week, and then delivers prototype and injection-molded samples within two weeks. This has helped the company stay competitive, adapt to changing requirements, and quickly bring new products to market. However, the company determined that its machines also needed more flexible and affordable controls.

New Capabilities Required

"While developing a new control system, we found that we needed controls that weren't as restrictive and tightly packaged as our previous solution," says Dan Shook, PakTech's operations director. "We also required a user interface that was specific to our equipment, so the look and feel would be the same across different PakTech platforms. Up until this time, we used touch panels from a large PLC manufacturer along with its proprietary software to create pushbutton interfaces, etc. We also wanted to develop a more brand-specific look and feel for our application machinery."

However, the compounding challenge was that PakTech competes against several builders with very low-cost machines that aren't elegant, but they do the job. "Offering a machine with better speed wouldn't win orders—it also had to be affordable. We needed to bring down our controls costs to find a better balance of performance and price," Shook explains. "Competing machines are often stuck at about 25 cases per minute with a lower-quality, die-cut handle. To reach 50 cases per minute, they offer two low-performance machines at $120,000, and run them in parallel, which isn't sustainable if you want to control plant floor utilization and machine footprint. The base PakTech model with our previous PLC-based controls cost $200,000 or more, so we had to expand our control ability, and reduce our costs, which we couldn't do with separate PLC and servo platforms. Layers of components just kept adding up, and we couldn't specify the control system we needed for less than $50,000 with our previous vendor. This was a serious threat to our competitiveness and sustainability. We decided that we had to have something like a PC tying everything together."

PCs + Robots = Flexibility

PakTech began working with Beckhoff Automation (www.beckhoffautomation.com) to redesign its handle application machinery, starting with its MPA60 Multi-Purpose Applicator, which can apply handles at 60 cases per minute. The firm's machines typically integrate with a conveyor and use presence sensors to detect and receive upstream products, control the sequence to a particular location, add handles, check for correct application, move products downstream for further steps, and communicate line speed to other plant systems. MPA60 uses a Fanuc robot arm that picks and places the handles, and its users need only minimal training to program it (Figure 1).

"PakTech aims to make the process as easy as possible for customers by installing the machine at the end user's facility," Shook says. "It cut the required training time in half for our customers by eliminating the time that previously had to be spent in the plant training the maintenance technicians how to navigate through the previous system. Now, the navigation is essentially as simple as pushing a button on the machine. We were initially introduced to Beckhoff's PC-based controls by machinery from Husky Injection Molding Systems (www.husky.ca), which we use to manufacture our plastic handles. This solution is what lets us program code more easily, push information back to the robotic equipment using a standard Ethernet interface, and perform remote maintenance."

By using PC-based controls, PakTech can provide machine information more easily to customers' ERP systems, "which wasn't so convenient in the past," Shook explains. "While it's possible to connect remotely using the traditional PLC, the required software license on the machine means the PLC is all you can see with that license. You don't see the HMI and you don't see the robot interface—those are all connections you must establish with separate licenses."

Controls, Software and Communications

PakTech's MPA60 adopted a Beckhoff embedded PC or industrial PC, as well as control panel, TwinCat software and HMI. To communicate, MPA60 uses EtherCat I/O and terminal box modules mounted outside the cabinets in harsh, IP67-rated environments. The motion system includes EtherCat servo drives, employed as variable-frequency drives, and servo motors. The CX1020 embedded PC was picked because it's a flexible, DIN-rail-mounted controller, and its 1 GHz processor makes it a powerful automation device, Shook adds. It's also small, measuring roughly 6x4.5x4 in. in PakTech's configuration, and it provides a direct backplane connection to the I/O terminals (Figure 2).