British packaging company Rexam (London, UK; www.rexam.com) needed a vision system to automatically inspect 100% of its containers in its North American beverage-can manufacturing plant. To check for inside-can defects and to inspect cans with mixed labels, the company chose Applied Vision (Akron, OH, USA; www.appliedvision.com) and its VTRAC intelligent machine software, an advanced process-monitoring technology. The software enables the system to immediately pinpoint the manufacturing component causing a defect trend and instantly alert line personnel to the exact upstream body maker, necker pocket, or spray gun causing the defect, as well as the source of a label mix-up. By eliminating the costly search and guesswork time typically needed to determine those sources, VTRAC helps to significantly reduce spoilage.
System hardware consists of displays and controllers, lighting and optics arrays, sensors and reject devices, and Applied Vision's proprietary servers. Cameras on the underside of output starwheels or neckers read the body maker ID and the spray dot and inspect for complete application of the UV rim coating. Cameras installed on output conveyors provide for inspection of the neck area and body. The mixed-label inspection systems, mounted after the light testers, automatically identify mixed labels, or "rogue cans," as well as gross decoration defects in the run.
"The real-time advantage of VTRAC goes beyond the monitoring, counting, and reporting functions of other process feedback and statistical analysis products," said Al Bohner, senior vice president, manufacturing, engineering, and R&D for Rexam BCNA. "We can now correct the source of a defect earlier and faster. This allows us to increase efficiencies, setting new industry standards for product quality."
