Tight as a drum: RFID-enabled e-pedigree simplifies product tracking, traceability
There are plenty of valid applications for RFID, but sometimes the technology just doesn’t seem practical. One example involves trying to use RFID to track 55-gallon metal drums containing liquids: Radio waves can be absorbed by the liquid and reflected by metal, which prevents reliable reads.
Now that doesn’t have to be the case.
Management for Midland, Mich.-based Dow Corning knew the company’s work-in-process (WIP) wasn’t as visible as it should be in the company’s ERP system. But Dow Corning had an internal group dedicated to exploring RFID applications, and the group determined that RFID would offer the means to improve internal material-handling processes by monitoring key information.
Dave Zuwala, assistant analyst for the manufacturing systems team and RFID consultant at Dow Corning, says the group realized the RFID application needed to:
• Do rapid reads on track material numbers, batch numbers, quantity, and other details,
• Generate an alert if materials went outside prescribed paths in the plant,
• Deliver a high level of container visibility—especially during key processing activities, and
• Establish transparency so operators can quickly identify drums and their contents.
With those goals in mind, Dow Corning began working closely with two of its suppliers: Lowry Computer Products , an RFID label converter and systems integrator; and Avery Dennison RFID , a manufacturer of RFID tag inlays. Together they developed a solution that also uses RFID readers from Motorola and RFID network infrastructure from Reva Systems , a developer of RFID network infrastructure products.
The resulting solution not only works effectively in close proximity with the liquid-filled metal drums, but also delivers a 100-percent read rate, says Zuwala.
|Dow Corning, a global supplier of silicon-based technology, recently worked with Lowry Computer Products to create a solution using an AD-900 inlay from Avery Dennison RFID, fixed and handheld RFID readers from Motorola, and Tag Acquisition Processor appliances from Reva Systems to track material number, batch number, quantity, and other details.|
Avery Dennison RFID’s AD-900 inlay—a durable, impact-resistant PVC tag tuned for direct adhesion to metal surfaces—is central to the solution. Designed with a PVC backplane to ensure the inlay is raised off the metal drum, the tag ensures accurate read rates at long ranges even though it’s close to metals and liquids, says Jeff Tazelar, Lowry’s RFID product manager.
The solution also uses Motorola XR 440 fixed readers, and Reva Systems’ Tag Acquisition Processor (TAP) appliances to control the process and allow users to manage product data and RFID readers. TAP appliances process all the collected data for location accuracy, and pass it to Dow Corning’s SAP enterprise software application via a certified interface, says Tazelar.
Dow Corning’s tracking process begins when 55-gallon drums are individually tagged in the manufacturing area with RFID tags enclosed in protective plastic sleeves. The four-drum pallet also is tagged. Each pallet is read by the fixed Motorola reader when it leaves the area, and by a Motorola MC 9090 handheld reader when it arrives in the repack area.
In the repack area, product is transferred from drums into smaller containers to fulfill customer orders. These smaller drums and containers also are RFID-tagged to document a “parent-child” association with the RFID-tagged 55-gallon drum. That way, the RFID database includes a chain of custody—or e-pedigree—which makes it easier to track and trace products.
Dow Corning has other RFID pilots under way as well. One project improves visibility of tanker-trailer movement between different fence lines within the manufacturing plant. This information is used to measure transport time and dwell time when moving materials among Dow Corning facilities.
“We can perform an RFID transaction at the gate as a truck leaves one site, and another transaction when the truck arrives at the other gate,” says Zuwala. “We should be able to learn a great deal from that.”