Beverage Can Light Weighting

Joe Norris

by Joe Norris

How Smart Skin Technologies Can Help

The use of aluminum cans for beer, soft drinks, energy drinks and other beverages continues to grow, thanks to global consumer acceptance and impressive marketplace success. By the numbers, that success amounts to billions of cans per year.

From the consumer’s perspective, these aluminum cans are lightweight, easy to chill, open and enjoy. Beverage manufacturers prefer cans as they can be filled at very fast rates when compared to bottles, and can be multipacked in many counts. They can also be sold as singles in larger sizes. Cans provide a complete beverage delivery system offering light, taste and CO2 loss protection, and they even offer an environmental advantage when recycled. 

Over many years of commercial use, aluminum cans have been subject to multiple light weighting programs, with gauge reductions and improved manufacturing processes and tolerances steadily reducing the can body weight and end weights. All of this has helped the industry to maintain the cost of goods in the face of fluctuating commodity metals pricing as well as challenges from other packaging materials. If they’re to maintain any of these material savings however, conversion plants can’t swing back and forth between multiple gauge and tooling changes. Consequently – with a single can plant serving many brand labels – can manufacturers must make gauge changes in lock step with customers. Likewise, their customers have to be prepared for ongoing light weighting changes.

When bottlers and canners are using older or worn filling lines (some even 20+ years old) to process 2016 lightweight cans, this global supply chain becomes even more complex.  These filling lines were adequate in the past, when cans were much heavier and speeds were slower. Nowadays, cans-per-minute and cases-per-hour are the new metrics profitable bottlers need to watch as they strive for high operational efficiencies, and low, just-in-time inventories.

But the consequence of chasing these new metrics can be damaged cans. Factors including line pressure and contact with each other, as well as contact with line control surfaces such as rails, diverters, and packer feeding lanes can all take a toll. This damage can manifest in wrinkles, rail marks, and heel and shoulder denting. With enough damage, suddenly you’re dealing with leaking cans in the shipping or trade phases (see photos).

Smart Skin Technologies and the Quantifeel system help to diagnose and correct these issues.  Can line pressure, can rotation and tilt data are measured and lines benchmarked to get ready for lightweight cans. The Quantifeel system identifies which parts of the line are contributing to the overall can damage, allowing manufacturers to make changes to motor speeds, motor timing and handling parts to soften or lower the forces acting on the cans at high speed. By generating a “ before and after” line pressure picture, manufacturers can benchmark the improvement – obtaining a data picture that correlates the adjustments made to the improvement in appearance and overall damage reduction in Class 1,2 3 defects.

          

The Quantifeel system records and responds to data provided through the use of an electronic drone can that goes directly into the running can filling line. Able to travel through warmers, twists, fill-level inspections, date-coding and all the way into packers, the drone collects vital data that it then sends to the Quantifeel software in real time.

Smart Skin Technologies’ software and analytics creates a report for manufacturers that highlights these types of damage –correlating the damage with the data. The pressure overlay report can show locations on the line of high and cycling pressure over multiple runs, while the operating system shows where on the can this pressure is being applied. As changes to the line are made, these areas can be retested and the new line pressure quantified.

 

Line Map Before and After Changes

 

 

The Quantifeel System provides data insights that not only help manufacturers to reduce overall line pressure, it also works to ease pulsing pressure in each area of the line to a safe level. Its unique line mapping software can produce an overview of pressure before and after changes. With this feature, line improvements can be benchmarked and then maintained. As a result, lightweight, cost-effective aluminum cans can be filled successfully, with overall damage reduced to meet brand standards, and leakers reduced, or even entirely eliminated.