Workpiece transport systems based on SuperTrak from B&R are compact, reliable and cleanroom friendly. On many production lines, they successfully increase output while introducing valuable flexibility to the production processes. PIA Automation uses track technology in an innovative process module to assemble medical devices both inside and outside the cleanroom.
At first glance, PIA's latest process module isn't particularly spectacular: a standard cell with a handling unit and a workpiece transport system moving items around. The handling unit picks small vials from the workpiece carriers and places them into a magazine.
A second look, however, begins to reveal some interesting details. The workpiece carriers developed by PIA each hold two vials and are mounted on shuttles. The shuttles travel independently through the system at different times and at different speeds. They reach dizzying speeds, change directions, stop and position themselves for each of the vials to be picked out of the workpiece carrier.
The PIA process module is perfect for demonstrating the key advantages of the SuperTrak system and modular workpiece carriers for potential users. Unlike conventional workpiece transport systems with rigid interlinking, such as rotary indexing tables or belt transfer systems, each SuperTrak shuttle can be assigned its own unique movement profile. This is possible because each of the shuttles is equipped with high-grade permanent magnets that correspond to the rotor of a linear motor – one that can be controlled individually. The stator is integrated in the segments that form the modular rail system that the shuttles travel on. Each shuttle has two v-wheels made of POM plastic that travel in a v-groove along the top of the segments to guide the shuttles safely around the track. Two more rollers run along a flat stainless steel guide to provide lateral support and prevent tilting.
Smaller footprint – Less particulate
Subject to only minimal rolling friction, these four rollers are the only moving parts in the entire SuperTrak system. The vials are transported gently in the workpiece carrier without touching each other or the transport system. "As a result, the service intervals for the workpiece transport system are exceptionally long," notes Lothar Mehren, head of the medical division at PIA Automation's competence center for healthcare in Amberg, Germany. "It also generates such a small amount of particulate matter that an exhaust system is not necessary. These factors all speak clearly in SuperTrak's favor. The system can be deployed in cost-intensive cleanroom applications to improve process reliability."
With the high costs involved, compact machine design is a high priority in cleanroom applications. SuperTrak stands out here as well, notes Manual Falk, account manager of PIA's medical division: "The linear direct drive system allows us to approach multiple positions in each station with high precision. That means we can integrate multiple transport, inspection or assembly steps in one and the same station, making the processes much more flexible. And, since positioning can be performed with the same high precision anywhere on the track, we can use every inch of it – including the curves. We end up with much better utilization of the available space, and the process modules can be added or omitted at any position. Taken together, these factors enable us to build a considerably more compact machine.
Short changeovers, more flexible processes
Integrating multiple processing steps in one station not only reduces the space required but also makes the system more productive, adds Falk: "Workpiece changeover times are significantly shorter than with other transport systems because of the short distances the shuttles have to travel. They can cover the distance between stations at high speeds and high acceleration and deceleration values. That's what makes the system so fast." Alternatively or additionally, changeover times can be reduced by placing multiple products of the same type on the workpiece carrier simultaneously. Depending on the timing requirements, they can then be processed sequentially at a single station or in parallel at two identical stations.
If a workpiece carrier has enough space to hold multiple products, a line can also be set up to process two different products or product variants without any setup between batches. The qualification requirements for medical technology only have to be carried out once.
Rugged and reliable
Since PIA designed the module primarily for process capability verification and high productivity, it was essential for the track system to be robust and reliable. "SuperTrak is technologically mature and thoroughly proven," explains Mehren. Falk notes another decisive advantage of SuperTrak over other systems: "SuperTrak runs as a self-contained subsystem. We are therefore free to decide whether we want to work with a higher-level plant control system and, if so, which one."
B&R also provides easy-to-use software for commissioning and configuration, so there's no need to manipulate the source code like other systems require. The software provides information about each shuttle, which can be retrieved – via OPC UA, for example – and easily used for functions such as condition monitoring and predictive maintenance.
High level of acceptance among employees and customers
The ease with which SuperTrak integrates into both new and existing software architectures has led to a high level of acceptance within the company, reports Mehren: "The SuperTrak technology and support from B&R have resonated very positively with even the most critical employees in the company."
The feedback from medical device manufacturers has been similarly positive right from the outset. "At the first public presentation of the cell at Pharmapack 2020, it was immediately clear that we had struck a chord with our customers," recalls Mehren. "The fast, fluid shuttle movements and quiet operation make quite a first impression." But the enthusiasm clearly went beyond first impressions. Shortly after the trade fair, the first orders for solutions with the SuperTrak workpiece transport system began rolling in. With the system's ongoing success, PIA now plans to expand the process module for the next Pharmapack event. The first steps will be to add a robot and a labeling unit.
"SuperTrak perfectly complements our existing selection of drive systems, and it has more than lived up to our expectations," summarizes Falk. "Other areas of the PIA group are very interested in the new track technology. It wouldn't surprise me if we start seeing the first applications there soon."
Lothar Mehren
Head of Medical Division, PIA Automation
"The service intervals for the workpiece transport system are exceptionally long, and it generates such a small amount of particulate matter that an exhaust system is not necessary. These factors all speak clearly in SuperTrak's favor. The system can be deployed in cost-intensive cleanroom applications to improve process reliability."