Supply Chain Brain

Co-op Uses RFID to Track
Plastic Bottles It Makes
for Coca-Cola in U.S.

Editorial Director Jean V. Murphy

A conversation with John Underwood, engineering manager at Southeastern

Container, the largest U.S. bottle manufacturer for Coca-Cola.

Southeastern Container, Enka, N.C., was formed in 1982 under the ownership of a group of Coca-Cola Bottling companies. Today the company operates as a manufacturing cooperative, producing 70 percent of the plastic bottles used by Coca-Cola in the U.S. It also works with bottle manufacturers outside of the co-op. The company recently implemented an RFID asset tracking system.

Q: Give us a brief description of Southeastern Container’s business.

Underwood: Southeast Container is a cooperative owned by a group of Coca-Cola bottlers. We manufacture for them unlabeled, unfilled bottles that they then fill and label. We have 10 manufacturing facilities across the East Coast and in Illinois and Wisconsin. At three of those facilities we have injection molding operations where we take PET [polyethylene terephthalate] resin in pellet form and produce what we call pre-forms. These are the thread part of the bottle attached to what looks like a large test tube. The pre-forms are shipped to our bottle-blowing locations where they are reheated and stretched and blown in a standard stretch-and-blow process.

Q: The assets you want to track are the containers for these pre-forms?

Underwood: That’s right. Until now, we have been using mostly cardboard containers, which have a relatively short cycle life. They also have stackability issues that prevent us from maximizing the capacity of shipping trailers. And the cardboard containers often are pre-assembled to save time, which takes up a lot of warehouse floor space. These issues add up when you are shipping billions of pre-forms, so we decided to move to returnable plastic bins. We already had a few plastic bins in use, but they were not optimized for loading on a trailer or for efficient return of empties.

The 30,000-plus new plastic bins we are adding to

our system are collapsible. They fold down on four sides into a nice, compact shape so that we can maximize their return to our injection operations. But these containers cost a lot more than cardboard and we wanted to be able to count their delivery/return cycles so we could track that against the number of cycles guaranteed by the manufacturer.

Q: Why did you decide to use RFID for this?

Underwood: Well, we already use and will continue to use barcodes to identify the contents of each box or bin, but that content changes with each cycle and a new barcode has to be applied. So the barcode can’t tell us how many cycles a box or bin has been through. As I mentioned, the bin manufacturer guaranteed a certain cycle life on these bins, and the only way to ensure that we get that guarantee is to count the cycles as the bins go through our system.

We looked at using a separate barcode to identify the bins but barcodes can come off and they are quite fragile—you get a scratch on them and they may not read well. An RFID tag, on the other hand, is rather permanent and rather protected, which ensures, with a high degree of certainty, that we can get an accurate cycle count on the bins.

As a piggyback on that, we are doing some other things with the tag information. For example, when we barcode the unit, we also read the RFID tag and associate both of those pieces of information, so we know what that particular bin contains. This provides a backup in case the barcode is not read for whatever reason—maybe it falls off or is damaged. As the bin makes its way back through the return cycle and we read the RFID tag, if we don’t have a record of the contents having been dumped, because the barcode scan failed at that point, then we go ahead and remove it from inventory based on the RFID read.