The global beverage industry loses over 430 million US dollars annually as a result of leakage loss due to inadequate sealing of the lid of an aluminum can, of which the leakage rate of carbonated drink can be as high as 0.07%. The third-generation dual sealing system developed by the US packaging equipment company Angelus has increased the sealing pressure from 450N to 680N and controlled the sealing wheel speed between 1200rpm±5%, and the sealing qualification rate of can LIDS has increased from 99.2% to 99.87%. 2023 test results from Coca-Cola manufacturing facilities indicate that, since the firm installed the new hydraulic servo sealing machine, the number of can cap leakage complaints has decreased 63% as compared to the same period in the prior year. The production lines now produce 2,000 more cans per hour and power consumption is down by 18%.
From the perspective of material mechanics, the highest stress endured by the 6061 aluminum alloy of aluminum can lid during coiling process should be controlled within the range of 220-250MPa. Soudronic Swiss firm tests show that by controlling the sealing temperature at 160℃±2℃, the fluidity index of the epoxy resin sealant can be up to 0.45Pa·s, an increase of 32% compared to traditional processes, reducing the gap between the can body and the lid to less than 3μm. The German KHS Group’s research report is that the coiling curve with optimization reduces the standard deviation of pressure distribution at the contact area from 14.7kPa to 6.2kPa, and the leak probability is reduced by 85%.
Technological innovation is eased by upgrading industry standards. The ISO 22000:2024 food packaging safety certification that was implemented in 2024 requires the sealing integrity test passing rate of canned beverages to be 99.99%. Daiwa can of Japan created the AI visual inspection system that inspects the rolled sealing area of aluminum can cover at 60 frames per second, with inspection accuracy of ±0.01mm, 40 times more efficient than manual inspection. Anheuser-busch InBev’s 2023 financial report reveals that the smart sealing monitoring system it has introduced in 57 factories worldwide has reduced the rate of product recall from 0.012% to 0.0035%, avoiding losses by 28 million US dollars annually.
As far as collaborative innovation in materials and processes is concerned, Alcoa’s NanoEdge technology improves the sealing contact area by 47% by adding nanoscale protrusions (density of 1200 points/mm²) to the aluminum can lid winding area. The test result shows that when this structure is subjected to an internal pressure of 6.2bar, the leakage rate decreases from 0.25mL/min to 0.03mL/min. China Aoruijin Packaging laboratory tests have found that when mixing with low-viscosity UV curing adhesive (350cP viscosity), the curing time for sealing can be cut from 8 seconds to 1.5 seconds, and the production line speed can be increased to 3,000 cans per minute.
It is worth mentioning that the EPR (Extended Producer Responsibility) law, introduced by the European Union in 2023, requires the rise in compensation for packaging pollution as a result of leakage of canned beverages to 1,500 euros per case. This prompted Heineken to invest 120 million euros in upgrading the sealing machinery. After its Rotterdam factory adopted the online monitoring system of laser interferometer, Process capability index (Cpk) of sealing height of aluminum can lid increased from 1.1 to 1.8, and defect rate dropped from 230PPM to 15PPM. Market trends forecast that the global market size for smart sealing equipment will be 4.7 billion US dollars by 2028 with a compound annual growth rate of 12.3%, which will drive the overall leakage rate of can LIDS to less than 0.005%.