Taking metal out of a beverage can delivers significant savings. Making sure the lighter can still performs as it should is another matter. Belvac Production Machinery’s Pilot Line is being used to test lightweighting, new materials and increasingly complex container designs before they reach commercial production. Iris Arsic reports.

There is not much room for error when making a beverage can lighter. Reducing the amount of aluminium can leads to significant savings for canmakers, but the finished container still must meet the same technical demands. Its walls thickness, base profile, neck geometry and flange all have jobs to do – and taking material from one part of the package can have consequences elsewhere.

It is a balancing act that has become an important part of the work carried out on Belvac’s Pilot Line. Installed in 2021, the line began with a specific need. Belvac struggled to find industry suppliers for preforms to support the development of both bottle and shaped container products. So, they decided to invest in a Pilot Line to manufacture preforms while simultaneously supporting internal and external research and development for innovation projects. 

What began as a solution to an equipment-testing problem developed into something broader. Belvac saw an opportunity to use the line for container development, lightweighting and downgauging, supplier testing, can-making training and its own R&D.

Today, the priorities vary according to who walks through the door. Brands may arrive with ideas for differentiated packaging, including shaped cans and aluminium bottles. For canmakers, the focus is often more firmly on material use. “Canmakers are typically most interested in downgauging opportunities to reduce the can’s weight as well as metal usage, as metal is the largest operating cost on a line,” says Eric Hodge, vice president of Business Development.

Less metal, same demands

One container engineering project provides a case in point: a can maker reduced annual metal weight by more than 7%, resulting in savings of millions per year, according to the company.

Getting there was not simply a matter of selecting a thinner aluminium coil. The lightweighted can was designed around thinner coil and a defined base profile capable of meeting requirements for dome reversal and dome growth. Engineers also optimised material thickness through the midwall and topwall, while the neck profile and topwall length were tailored to achieve the required axial loads and flange geometry.

Despite those changes, Belvac says the container did not require a different production process: the front-end and back-end processes remained the same. The Pilot Line was instead used to find out whether the design – and the tooling required to manufacture it – worked as intended.

“The Pilot Line played a very important role in the development, testing and validation of this can design,” Carlos Mejia, director of Global Beverage Packaging, notes. “It allowed Belvac to validate cupper, bodymaker and necker tooling design, manufacturing characteristics and to confirm that the finished can complied with required performance.” That included dome growth, dome reversal and axial-load requirements.

From simulation to physical testing

Much of modern container development happens before a piece of metal ever reaches a machine. Belvac utilises Finite Element Analysis (FEA) to fine tune the container design with real performance data which improves correlation on future designs. This modelling and simulation allow engineers to evaluate designs and predict how a container should respond under different conditions. They can narrow the possibilities, expose weaknesses and help determine whether a concept is likely to work.

Physical trials then show how the design performs under actual production conditions. “Modelling and simulations are theoretical and cannot be used as a substitute for real life product,” says Mejia. “These programmes work in tandem to provide the highest likelihood of success of the container, but nothing can replace real life production.”

For Belvac, that is where the Pilot Line becomes particularly useful. Physical production allows its engineers to validate metal-forming tooling for the cupper, bodymaker and necker and identify potential problems as a design moves towards a high-speed manufacturing environment. “This validation is crucial for the success of the product start-up and line commissioning in the can plant,” says Mejia.

Trials also allow changes to be made before a customer commits to the tooling and manufacturing equipment required for commercial production. Engineers can see how the metal responds through individual processes and make adjustments during development rather than after the package has reached mass manufacturing. “The Pilot Line by nature is designed to reduce as much risk as possible,” says Hodge. “Being able to mimic real-world production conditions allows Belvac to help ensure the highest likelihood of success.”

More than lightweighting

Metal reduction may provide one of the clearest economic arguments for Pilot Line testing, but it represents only part of the work being carried out. Suppliers have approached Belvac to test a wide variety of products including alternative coil materials, bodymaker coolants and lubricants, washer chemicals and external and internal coatings.

Brands bring a different set of challenges. They are increasingly interested in new container concepts and differentiated shapes, including shaped cans and bottles. But the further a design moves away from conventional geometry, the more difficult it can become to manufacture. That can bring production engineering into the conversation much earlier.

Some customers approach Belvac with little more than an ambition to add a differentiated package to their product mix. Others arrive knowing precisely what shape or modification they want. “The more unique the shape, the harder to manufacture,” says Hodge. “Customers typically involve Belvac from the ideation phase to get a better understanding of what are the limitations from manufacturing.”

The company can then help refine the original concept with those constraints in mind. A container may work as a design, but it also has to work in production.

Beyond the initial remit 

Belvac is also using the Pilot Line for its own product development. One recent project has involved a carrier ring for aluminium bottles. According to the company, the Pilot Line allowed its R&D and container design teams to develop a new container concept alongside the equipment needed to produce it at industry speeds.

A line originally intended to provide the preforms Belvac needed for equipment testing is now being used by can makers looking to remove metal, brands exploring new shapes, suppliers testing materials and chemicals, and Belvac’s engineers developing their own technologies.

The company expects that role to grow as pressure to reduce material use continues. “As the industry continues to push forward reducing net can weights and used metal in cans, trial and testing will become ever more important,” Hodge concludes.