Integrating RFID into manufacturing
Wells’ Dairy may have been the first food company to integrate RFID into its existing control architecture, thereby improving its processes.
The implementation of RFID technology was catapulted forward in June 2003 when America’s largest retailer, Wal-Mart, issued a mandate requiring its top 100 suppliers to include RFID tags on all cases and pallets entering its distribution centers to better track products and increase efficiencies.
While the implementation deadline was not until Jan. 1, 2005, most Wal-Mart suppliers immediately set to work because it looked like a daunting challenge. One of the first companies to meet the RFID challenge head-on was Wells’ Dairy. The company supplies ice cream and frozen treats to Wal-Mart customers under the Blue Bunny brand.
|"For us, success relied on the integration of the RFID readers into the control architecture," explains Brad Galles, Wells' process controls manager.
Wells’ Dairy operates the world’s largest ice cream manufacturing facility in its home town of Le Mars, Iowa. Cited by industry experts as one of the most technically advanced plants in the industry, the highly automated production lines in Le Mars run up to 160 hours per week.
Wells’ Dairy knew implementing RFID technology wouldn’t be easy, but it also recognized the technology’s potential to improve operations and provide a competitive advantage. This meant going beyond simply complying with the Wal-Mart mandate; Wells’ saw the potential to re-engineer the supply chain and provide visibility of the product through the production process, as well as the possibility of harvesting data from the production line control system for greater intelligence and improved decision-making. Wells’ Dairy wanted to integrate RFID into its existing Rockwell Automation infrastructure for maximum impact and return on investment.
“The beauty of RFID lies in its ability to add value through increasing plant-floor visibility, which it does by collecting data in a way that’s compatible with equipment we already have,” says Brad Galles, process controls manager for Wells’.
The power lies in the system behind the tag. The RFID tag is linked to a database that holds the production attributes of each ice cream bucket — time, batch ID and production line. With this, Wells’ Dairy knows precisely what time every tag was applied and from what batch the pallet was produced.
“From the outset, we viewed the implementation of RFID technology as a catalyst for making process changes that improve business performance,” says Galles. “Once the data is collected, we’ll use it to improve inventory tracking, automate many of our quality control and inventory processes and simplify our data collection.”
Using the wealth of market information available on RFID, Galles and his team of engineers quickly were able to determine the direction they wanted to take with the pilot program. After creating a preliminary outline, Galles began talking to the suppliers — RFID tag and reader companies, automation control suppliers and RFID consultants — each with a different perspective on how to implement RFID.
“We knew what we wanted and what direction we didn’t want to take,” says Galles. “Many suppliers were taking a ‘wait-and-see’ attitude in regard to RFID; as a result, many simply focused on short-term ‘slap-and-ship’ solutions to meet compliance requirements. If we were going to do it, we were going to do it right the first time. For us, success relied on the integration of the RFID readers into the control architecture.”
The pilot line at Wells’ Dairy became a testing ground not only for the technology as a complete solution for the facility, but also for many of the RFID products themselves. As RFID tag and reader suppliers continuously rolled out new products, it became a challenge for Wells’ Dairy to implement a pilot program that delivered reliable, repeatable results, especially within the tight time frame.
“The truth is, there was very little information that was proven,” says Galles. “And the only way to get good, accurate information was to get the equipment and test it in your own facility. As a result, we learned a lot about the technology’s capabilities and drawbacks through trial and error.”
The Rockwell Automation Integrated Architecture was the foundation of Wells’ automation and control systems. That included Allen-Bradley ControlLogix controllers, NetLinx networking technology and the ViewAnyWare visualization platform.
“In order to achieve maximum value for our investment, it was important for us to design the RFID system using the same control platform that our existing processes employ,” Galles says.
As the first company to implement an RFID application that was seamlessly integrated into its existing control architecture, Galles and his team broke new ground and in doing so drove the development of new technology — an interface module that connected the RFID side of the solution with the control architecture.
|When it decided to implement RFID technology, Wells' Dairy also planned for ways to use the technology's potential to improve operations.
The linchpin in the solution — the Allen-Bradley 1756-EWEB module for ControlLogix — ties the data received from the RFID tags back into the company’s existing information architecture. Once the information is passed from the RFID reader into the control architecture, the information can be shared throughout the enterprise.
Wells’ Dairy designed the pilot program for its largest line of ice cream. The continuous production line spans the process from raw materials to packaging.
Once the raw ingredients are mixed into the proper recipe and, in this particular line, packaged into family pails, the ice cream packages are brought by conveyor to the wrapper machine where two buckets at a time are bound together with plastic wrap (considered a case by Wal-Mart).
As the case exits the wrapping machine, an RFID tag embedded in the barcode label is placed on the plastic wrapper by one of two applicators that are in communication with each other so that if the first one misses the second one will apply the tag.
As the cases begin their ascent into the freezer, the RFID tag is read. If the reader does not recognize the tag, the case is diverted to a reject line and manually reviewed by the line attendant to identify the error. According to Galles, the most common error for the pilot program was misreads between the tag and the reader.
This portion of the pilot line is monitored through strategically positioned operator interface terminals. When exiting the freezer, the ice cream tubs are read again to verify the tag adhered during the quick-freeze process and to track each one as it is palletized.
As the ice cream travels from room-temperature production lines to below freezing and then to storage in -20°F warehouses, the dramatic change in temperature often caused the labels to peel off. Another challenge was finding readers to decipher individual ice cream tubs speeding by on the conveyer or capable of reading stacks of ice cream buckets entering storage on a pallet. Ultimately, through the review process, Wells’ Dairy has the readability and reliability necessary from the selected readers and tags.
After 75 gallons of ice cream move onto an automatic palletizer, the pallet is taken by forklift to a wrap machine. Once it is wrapped, another RFID tag is affixed to the pallet and confirmed by an RFID reader. The new tag contains the information gathered on the individual ice cream buckets throughout the production process. The pallet is then stored in the warehouse before it is ready to be shipped to a Wal-Mart distribution center.
“We refined the process with our largest line of ice cream,” says Galles. “And I’m glad we did, because we now don’t anticipate any major issues during the rollout. If the pilot had been smaller or set up remotely, we would not have identified many problems — like having tags fall off in the quick-freeze portion of the process — we’ve now solved and moved beyond.”
Throughout the 18 months of the project, Galles and his team developed a solution that enabled the company to both comply with Wal-Mart’s RFID mandate and position Wells’ Dairy to take advantage of the information gathered by RFID. Improvements included increased quality control, information gathering, safety and productivity for induction of products into storage. Additionally, the solution has freed up personnel, helped increase accuracy of freezer counts, decreased the number of misshipped pallets and minimized the need for manual reconciliation.
“With the implementation of the RFID pilot, we found many opportunities for RFID technology,” adds Galles. “In addition to the opportunities that we defined in the business case of this project, we realized other areas where this technology brings added value to Wells’ Dairy.”
For more information, contact Rockwell Automation at (440) 636-3105 or see www.rockwellautomation.com/solutions/rfid/.