Robotic palletizing system enables track and trace quality control

Lorillard Tobacco, a 250-year-old company headquartered in Greensboro, N.C., produces approximately 40 billion cigarettes each year. Its 1-million-square-foot plant houses 36 packaging lines that produce 41 different product types. In response to new industry regulations in 2009, the company installed a robotic palletizer to ensure visibility and control of product quality.

The company had used a multi-line palletizing system at the facility for more than 30 years, with all 36 production lines feeding two conventional high-speed palletizers. Although the legacy system met all requirements for throughput, reliability and safety, its design caused difficulty when tracing defects and damage back from pallets to production lines.

“If you had a problem on one packaging line but had six others that were producing perfect product, finding the defect required you to search through all of the cases produced during that time period, regardless of packaging line,” says Randy Marshall, senior staff engineer for Lorillard. “If we installed a new multi-line palletizing solution, it had to be completed in a very short amount of time. I couldn’t figure out how to do it, nor was I willing to accept the risk of shutting this factory down.”

The end-of-line operation presented a unique set of challenges. Most importantly, the pallets must be composed exclusively of cases from the same production line to enable easier track-and-trace capability throughout the plant. The system must also accommodate eight different case sizes, each with its own stacking pattern.

The solution they chose includes 18 robotic palletizing cells (Intelligrated, intelligrated.com), each serving two of the facility’s 36 production lines, a design that includes significantly less conveyor than before. The compact footprint of the robotic system enables a system design with a direct connection between the palletizing cell and each production line.

“It’s a very simple way to palletize cases,” Marshall explains. “It makes traceability much easier.”

The installation of each robotic palletizing cell took place over a four-week schedule, which required shutting down two of the production lines for two weeks. After the first cell finished testing, the phased rollout process continued until the final cell 22 months later.