PETpla.net Insider 10 / 2013

BOTTLE MAKING 50 PET planet insider Vol. 14 No. 10/13 www.petpla.net installed Agr’s OptiCheck as “the last line of defence” before the containers go through the wall to the customer facility. The compact OptiCheck is an inspection and measurement system that offers both in-line gauging of critical finish dimensions and defect detection for seal surface-related problems. With its ability to measure finish dimensions inline to an accuracy of 0.002 inches, OptiCheck is well suited to the needs of blow-trim contain- ers. Its finish gauging module uses a proprietary configuration of multiple cameras, LED-based backlighting, and high-speed imaging to measure the critical dimensions. Robust image analysis algorithms accurately identify flaws and blemishes, such as whisk- ers left from trimming, which had been a frequent but hard-to-detect defect on the Graham line. “We are looking at the diameter of the neck, the height of neck, and A, T, E, and H dimen- sions of the wide-mouth jars so after filling the cap and tamper band can be fully engaged,” Graham process tech- nician Josh Chesley points out. Fine-tuning blowmoulder control To neutralise the inconsistencies in bottle manufacture, be it environmen- tal conditions or variations in pre- forms, Graham installed Agr’s Process Pilot system to gain additional control over the blowmoulding process. The Process Pilot incorporates interac- tive software along with a series of sensors providing high-precision wall thickness measurement. These work in conjunction with the blow- moulder controls to proactively manage material distribution in the bottle or jar. Because the system adjusts mul- tiple blowmoulder parameters simul- taneously - lamps, blow pressure, and timing, for example - the plant can maintain tight process control limits to produce jars that meet or exceed customer expectations with minimal operator intervention. “You initially set up the blow- moulder to make the bottle with the desired thickness properties, the baseline,” Waud explains. “The Process Pilot system manages it from there, continually adjusting the blowmoulder every one to two minutes to maintain the baseline thickness distribution as the process changes throughout the day or night.” Being able to accurately monitor and manage material distribution of the container is a key benefit for this application. To withstand the custom- er’s higher filling temperatures, the hot-fill jars must be more rigid than traditional bottles. The Process Pilot’s sophisticated algorithms analyse minute changes in material distribu- tion, using the feedback to adjust critical blowmoulder settings so proper thickness distribution is maintained. Before the blowmoulder control system was installed, Graham opera- tors would monitor the reject rate on the OptiCheck for thread dimensions. When an issue was detected, they would make adjustments to cor- rect the blowmoulder. Now, with the Process Pilot in place, adjustments for material in the thread region are performed automatically. During the Process Pilot instal- lation, the Agr engineer used the system’s graphical data display to illustrate variations in blowmoulder performance and the impact of opera- tor adjustments while the machine was running without the automated controls. Waud comments that the graphic depiction of the process on the full-colour process management screen was especially useful in help- ing operators understand the impact of their changes to blowmoulder set- tings. According to Graham, installing the automated control system has generated many measurable benefits for Graham’s blow-trim operations: In just one year’s time this approach has generated 52.7% improvement in waste reduction. Factoring in produc- tivity improvements and reduction in waste, the payback on the equipment investment is estimated at less than a year. “We don’t run our jar line without the Agr systems,” Waud concludes. www.grahampackaging.com www.agrintl.com Agr’s Process Pilot system works in con- junction with the blowmoulder controls to proactively manage material distribution in the bottle or jar.