Wurth Oy Retools Its Picking Line

According to Känsälä, Würth decided to implement a system in which data for directing the conveyor belt was placed on tags instead of in an external database, because the company was happy with the way the previous system worked and did not want to go through the process of redesigning a new one. In addition, both the old and new systems had to be operational simultaneously during the switchover to the new technology. Finally, Würth wanted the picking stations to operate independent of network connectivity—that is, it did not want to rely on a WLAN or cable connection linked to a back-end system, in case the connection were to fail.

The planning and testing of the system began in September 2009, and the first new readers to be installed became operational in January 2010. Vilant added additional readers, step by step, until the project was finished this month.

RFID readers identify each container that passes by and make sure it is routed correctly.

For Känsälä, the project's big challenge was to implement the new RFID system while still operating the old one, so that the picking line would experience no downtime.

"During the ramp-up of the new system, we had to circulate containers tagged with both UHF and LF tags, and we had to replace old readers with the new readers, one by one," Känsälä explains. "We had to make sure the data on both tags on each container was the same, and make sure the data was passed to the back-end system correctly... Since the systems needed to be interchangeable with each other, many restrictions were created that you don't have when designing a system from scratch."

Würth's managers plan to use the new system to collect better data for quantifying how often each picking station is used, Känsälä says. Such information may help them maximize the use of each station, by eliminating picking bottlenecks.

According to Känsälä, some customization of the software in the readers was necessary so that the information could be used to direct the conveyor belt.

At a later date, Känsälä says, Würth plans to use the RFID system to eliminate all paperwork from the picking process. Currently, a worker looks at the picking list, fulfills the picking order by placing the items in the container at his or her station, and then uses a pen to mark the task as completed on the list. The system that the company envisions would present the employee with an electronic picking list associated with the RFID-tagged container that is guided to the picking station. The list, on a handheld reader, would inform the worker about which shelf to go to for picking.

Känsälä declines to reveal the amount of money Würth invested in the RFID system.