Stefan Welker brings over 18 years of dedicated experience in the packaging industry, with a strong focus on inspection systems. His expertise spans the entire process from designing and specifying systems to developing advanced measurement and image processing solutions. This conversation offers a deep dive into how Industrial Physics is driving quality assurance and innovation in the aluminium packaging value chain, particularly as the world pivots toward sustainability and circularity. As sustainability gains momentum and recycled aluminium becomes more prevalent (and often more variable in quality), precise testing becomes essential. He further provided overview about how Industrial Physics helps detect faults early, reduce waste, and prevent costly recalls all while supporting lightweighting trends that reduce material use and carbon footprint.
AL Circle: Can you briefly introduce Industrial Physics and its role in the aluminium packaging value chain? With the growing global shift towards sustainable and recyclable materials, how do your products support quality assurance in aluminium packaging?
Stefan Welker: Industrial Physics offers an extensive range of solutions throughout the packaging process, from trimmed cans (where the top edge has been precisely cut to remove excess material) to lacquer finishes, ink decoration, and final filled products.
Our gauge technology is designed to measure aluminium and steel. The core requirements may vary (e.g. wall thickness, volume), but our role across the value chain remains consistent: to protect the integrity of can-makers and fillers through reliable test and measurement.
Industrial Physics is a global leader specialising in instruments that test and measure a wide range of materials for use in industries such as packaging. Within aluminium packaging, especially in sectors like beverage, we offer quality assurance solutions that help manufacturers maintain consistency.
As sustainability has become a driving force globally, aluminium packaging - being lightweight, recyclable, and infinitely reusable - has gained significant traction. Our equipment supports this transition by ensuring the structural integrity and performance of aluminium packaging, allowing professionals to reduce waste, minimise recalls, and enable circular economy practices. As recycled aluminium quality declines (e.g. via downcycling), precise quality control becomes even more important.
AL Circle: What are the most critical parameters tested in aluminium beverage cans, and which of your instruments are commonly used for these applications?
Stefan Welker: At Industrial Physics, we have a significant product portfolio of test and measurement solutions so that we can be a partner to our customers, anticipating how their needs will evolve in line with industry trends and regulations too.
There are many critical parameters that require testing in canmaking, from lacquer adhesion to coating, and we have test and measurement solutions available for the full length of the process. However, since the growth in traction of processes such as light weighting reducing the weight of cans by decreasing the thickness of the metal – there are several parameters in particular that are impacted and have become an even bigger focus for testing.
There are multiple Industrial Physics systems designed to support light weighting and accelerated Statistical Process Control (SPC): collecting data, analysing control charts and supplying stats required to take corrective actions. Our inline gauges allow for automated sampling up to 1,200 cans in 24 hours, compared to just 24 per shift manually, which is a common practice in the industry today.
Seam inspection is also essential. Our CMC-KUHNKE SEAMscan XTS III is a fully automated, stand-alone measurement system that provides accurate results which are faster and safer than conventional cross-sectional methods. The non-destructive system allows you to assess many parameters, including seam thickness, countersink depth, seam height, body hook and wrinkle rating (% tightness) with no damage to the can on the production line. It significantly increases the accuracy of testing and reduces both labor and spoilage from batch recalls due to leaks.
Another key test is Dome Reversal (also known as a Bucket Tester): designed to determine the exact pressure at which the bottom dome of a can begins to buckle. This is critical in lightweighting to avoid failure under heat or pressure – preventing a can exploding in high heats such as being left in a hot car, for example. This can be effectively tested with the Torus Z308: Which provides accurate and reliable measurements for dome growth and dome reversal ensuring cans meet stringent performance requirements.
AL Circle: How do you enhance inspection efficiency and accelerate production rate using gauges?
Stefan Welker: Our Torus gauges – including front-end and compound placement systems – automate sampling and increase inspection frequency to match high-speed lines (up to 3,500 cans per minute, one of the fastest processes in canmaking). Inline or semi-automatic systems provide real-time feedback and far better process control.
Our Torus Front-End Gauge measures key dimensional parameters early in the process. This process eliminates operator subjectivity, improving reliability and repeatability, helping reduce waste costs further down the manufacturing process.
Our Torus Compound Placement Gauge uniquely identifies individual shells (the main cylindrical body of the can that holds the contents) before compounding (the application of specialised sealing compounds to metal cans), then tracks weight and placement to individual spray guns. This offers a vital breakthrough in waste reduction and defect traceability. The tracking capability adds considerable value. When there are any discrepancies in weight, users can locate the specific faulty spray gun, eliminating the issue before production is impacted. The compound weight is automatically calculated and displayed for the operator for each can shell, and the barcode verification feature also removes the risk of manual data entry errors.
AL Circle: How do you foresee the aluminium end-user sector evolving over the next 5–10 years, especially with the push for decarbonisation and circularity? Are there specific geographic markets where you see increased demand for aluminium testing solutions? Why?
Stefan Welker: The aluminium sector will continue growing, especially with sustainability goals driving adoption. Recycling aluminium saves up to 90 per cent of energy vs. virgin material, making it ideal for decarbonisation efforts. We’ll see increasing demand for testing as recycled content grows and material quality varies.
A huge majority of drinks cans are aluminium, but food cans will likely remain steel due to easier weldability and better suitability for the retort process. However, aerosol packaging and aluminium bottles show promise for evolution: Asia is already investing heavily in this shift – and is moving aerosol cans to aluminium.
In Europe, growing deposit return schemes are increasing recycling rates (particularly in the likes of Netherlands, Austria, Eastern Europe). We're seeing increasing demand in Asia-Pacific and South America, where sustainability policies are also gaining momentum. These regions require robust infrastructures to support new production capabilities.
We're seeing rapid growth in beverage cans (carbonated drinks, energy drinks, and craft beverages); personal care (aerosol containers and cosmetics); health & wellness packaging (health drinks). Sustainable water bottles and resealable aluminium containers and even the futuristic resealable can. The combination of consumer demand for eco-friendly packaging is driving the expansion across these sectors.
AL Circle: Could you share examples or case studies where Industrial Physics has partnered with aluminium can or bottle manufacturers to improve packaging performance or reduce waste?
Stefan Welker: Industrial Physics has worked with several major aluminium can producers and recently partnered with a leading beverage company to automate their inspection processes.
This has led to a reduction in material usage through improved process control, as well as a decrease in defective production, enhancing overall productivity. Our collaborative approach ensures that testing is tailored to each customer's production goals, whether it’s reducing waste, ensuring safety, or meeting sustainability targets.
AL Circle Surface treatments and coatings are vital in aluminium packaging. What solutions does Industrial Physics offer for testing coating quality and uniformity?
Stefan Welker: Our SpecMetrix technology provides highly precise and accurate coating thickness and weight measurements. Proper and consistent application of coating is vital to quality and performance of aluminium packaging. Precise measurements from SpecMetrix not only help ensure higher quality coated products but also help optimise the amount of coating applied to help reduce costs. SpecMetrix systems can also help measure coatings on coated coil to ensure that the right amount of coating is applied before can ends are made from the coated coil material. Rising demand in varied end-use presents an opportunity for coil coaters to grow operations and output if they can navigate the sector’s challenges – which is where testing innovation can help.
SpecMetrix Prime and EXR testing technologies provide absolute coating thickness measurement in virtually any lab environment or directly in-process on global metal coil coating lines and metal packaging lines. This offers access to real-time data that allows the user to gain accurate thickness measurements. Coating and paint waste are reduced as the coater is only using what’s needed, while reducing the risk of undercoated products being sent to the manufacturer. Reduction in aluminium and coating waste allows the manufacturer to meet sustainability targets – increasing operational efficiencies overall.
AL Circle: How do you adapt your technologies to meet the evolving needs of the aluminium packaging sector, especially with innovations like resealable aluminium bottles or slim cans? What new innovations or product developments can end users expect in the near future?
Stefan Welker: When developing resealable containers, many companies use plastic to create the component that seals the container. The introduction of plastic to the material mix complicates recyclability. There’s no mass-scale shift yet that justifies major investment, though we remain flexible for custom solutions.
More broadly, we’re seeing a shift from pure quality assurance toward process control. It’s no longer about just identifying defects: it’s about using inspection data to adjust the process before problems occur.
In the future, we will see a move beyond compliance – exceeding ISO standards (e.g. performing full 360° seam inspections, not just three-point checks on equipment, preparation, and processing). When performing traditional destructive seam inspection at two to three points along the double seam, you risk missing problems that arise as close as a few millimetres from your measurement points. 360 seam inspection measures 100 per cent along the double seam and ensure that these faults are detected, eradicating the problems that follow when you ship bad cans.
As expertise on production lines declines, due to a shortage of skills, our technology must support decision-making automatically. Our engineering teams are focused on modernising core gauges and developing smarter, connected solutions that help customers control their processes more proactively – not just catching problems after they occur.
We closely monitor emerging trends – such as slim cans, resealable bottles, and decorative printing technologies – and adapt our instruments accordingly. Innovations include enhanced multi-format capability in our testing machines and non-destructive testing solutions to reduce scrap during production. Looking ahead, we are investing further into modular platforms that scale with production needs, and data integration tools to support smart factory initiatives.
