From a short-term hold-for-inspection (HFI) delay on the filling line through to a full-scale product recall, any scale of problem with a filling operation can have a major financial impact for a brewer. Leaking cans and bottles that affect shelf-life, incorrect labelling and foreign objects in the product are all issues that brewers – and beer lovers – are keen to avoid encountering.

While packaging manufacturers employ numerous test and inspection systems to all-but guarantee their products leave the factory ready to be filled, packaging can be damaged or contaminated during the logistical process of travel, warehousing and unpacking. Similar systems are therefore used by fillers at the beginning of the filling line, to detect damage and dirt.

The light weight of empty cans that makes them a low-cost packaging to ship to the brewery also makes them susceptible to minor dents – which are easy to overlook but can compromise the package’s integrity over the duration of the product’s shelf-life. It’s therefore unsurprising that a range of empty can inspection systems are available.

Heuft’s CanLine systems operates at up to 144,000 cans a minute – enough to handle a full-speed beverage can manufacturing line and therefore suitable for filling operations as well. It’s powered by the company’s Reflexx2 image-processing system, and is designed to identify deformations, indentations and other damage – focusing particularly on the quality of the flanged edge of the unfilled can, critical to the delicate double-seaming operation at the opposite end of the line. A deformed flange or neck can result in the seal either failing completely or, potentially more problematically, not sealing tightly enough.

The CanLine system also highlights dents to the body and base of the can, as well as dirt and foreign objects, using LED illumination to provide a clear view of each can for analysis.

The Innocheck ECI – empty can inspection – system from Germany’s KHS addresses similar issues. Running at up to 2,000 cans a minute, the system uses one camera – with an option of a second for improved performance – to capture images of the can wall, base and top edges. The Innocheck software developed by KHS provides not just image analysis to detect any faults, but also individual can tracking, to ensure that any cans determined to be faulty can be automatically rejected from the line.

The system has been designed to be compact, to fit into the filling process as unobtrusively as possible, and importantly emphasises a hygienic approach, particularly on the inspection head. The company also highlights the long life of the LED lighting system, reducing the maintenance required.

The Ultra Compact ViS from Ibea, as the name suggests, also focuses on a space-efficient, single-lane process. Key to this is integrating the complete PC system within the ViS, meaning that no external computer is required to process the images – the whole system consists of just the accompanying monitor, keyboard and mouse.

The complete in-house hardware and software guarantees reliable round the clock production and is compatible with components of diameters up to 190mm and heights of up to 300mm – so there’s plenty of scope for inspecting tallboys, stovepipes, crowlers and all the other capacious can sizes being adopted throughout the craft brewing industry.

As well as being able to analyse component dimensions, detect damage and flaws in panel, body and flange, and a number of other options, the software was developed with reflective surfaces and materials in mind – making it particularly well-suited to metal components such as empty cans and crown corks.

The system includes Ibea’s Real Time System (RTS), operated by a gear clock and controlling the image scanning and illumination processes and up to three ejectors, synchronising analysis and rejection to ensure bad products don’t reach any further down the filling line.

German company Krones offers high accuracy inspection systems for empty cans, glass bottles and PET bottles. The company’s Cantronic system runs at line speed, inspecting cans for contamination and deformation.

A high-resolution CCD camera inspects the base, wall and flange, while an optional extra camera is used to detect wrinkles and dirt in the neck area of 202-diameter cans – slim cans commonly used for energy drinks. Any cans detected as faulty or ‘risky’ are automatically rejected and the details recorded, a safeguard protects the product quality and increases overall line efficiency by 5%, says Krones.

The company also produces the Linatronic 735 for inspecting empty glass and PET containers. Hygiene is understandably a priority, and the system features conveyor belts that repel dirt and moisture, a closed outer surface in the conveyor belt station, and a structure designed to prevent dirt building up above the bottle flow.

Using a camera and a sensor, the system inspects the inner and outer side-wall, sealing surface, base and thread for integrity and contamination and checks for any residual liquid inside the bottles.

As well as providing systems for single-use glass bottles, Krones has also developed a unit in the EBI range for inspecting returnable glass bottles.

The system is designed to offer improved side-wall inspection accuracy, combining four four-megapixel cameras and crack detection capability in the neck finish section. Accuracy is further improved by the double-flash neck finish inspection, and base inspection with pre-centering. The unit is also optimised for transparent bottles with scuffing and engravings.

Closing Thoughts

Once each empty container has been checked and verified as free from defects, they reach the filling stations. Here, systems such as the Filtec 3 are designed to flag up any of the various issues that can arise during filling and closing the containers.

Potential problems include overfilling and underfilling each can or bottle, and the can end or bottle lid either being fitted incorrectly or, if the hopper has run out of these components, missing entirely.

The Filtec 3 inspection system detects these issues as they arise on the filling line, as well as identifying bulged cans, high or low foam levels, glass bottle breakages, containers falling over on the line, and where applicable, missing foil seals.

The system is more than capable of handling filling line speeds – it runs at up to 2,400 cans a minute or 1,400 bottles a minute – and collects data as it goes, keeping count of the total number of containers analysed and the total number of rejected parts. It also offers real-time continuous statistical analysis of the data, and uses sampling to monitor the performance of filler valves and the capping and closing heads, enabling the system to identify if a fault within an individual station is causing rejects.

As with the empty container inspection systems, the Filtec 3 recognises the lack of space typically available when installing machinery within a filling line, and is built with a deliberately small footprint.

For brewers using cans, the closing process involves what could quite reasonably be described as an unheralded wonder of engineering – the double-seam. The intricacies of how such an impermeable barrier is formed – keeping high-pressure gas inside beverage cans for years and food safe to eat for decades – at line speeds is a topic to be looked at in detail another time, but seaming can safely be described as both an art and a science and is understandably the focus of a large number of dedicated inspection machines.

These machines have been developed to be compatible with today’s generation of ultra-thin beverage cans. The can manufacturing industry has made ongoing efforts to downgauge the thickness of its products, as although each step only reduces the weight of each can by a fraction of a gram, with standard can production operations typically manufacturing over a million cans in a shift on just one line the cost savings and environmental benefits soon add up.

This approach has also been applied to can ends, resulting in brewers running seaming operations which demand two pieces of metal both thinner than a human hair to be accurately bound together.

As a result, it’s beneficial for filling operations to analyse as many seams as possible – not only to detect potential flaws, but also to identify trends in seam dimensions which can provide an early warning sign that the process may be going out of specification, allowing the operator to make modifications before faulty seams are produced.

This requirement has seen x-ray technology introduced – the non-destructive process making it possible to return products to the line after analysis, unlike the alternative approach in which the seam is cut open for measurement, and therefore allowing the seam monitoring process to take place without eating into productivity.

An example of a latest-generation system, Torus Group’s SEAMetal HD was developed by Israel-based Quality By Vision, who Torus is the UK and Ireland agent for. The company highlights not just the issue of lightweighted cans and ends, but also pressure to increase line speeds as a further cause of potential issues arising in seaming operations.

The company first introduced a computer-based, fully-automatic double seam inspection system back in 1993, and has continued to develop the detection algorithm to improve the accuracy and repeatability of the measurements.

Its key benefits are fast, high-resolution and high-accuracy x-ray imaging, using an integrated high-definiton camera and an SPC system that provides automatic measurement and data collection of each of the seam dimensions. From there, the software can present the information in graph form, and has compatibility with Microsoft Excel to produce customised reports.

CMC-Kuhnke’s Mars-XTS combines two modules, the SeamScan XTS to make internal measurements with an x-ray system, and its CSG-Series Combination Seam Gauge for taking external measurements. The result is a system that can measure a range of dimensions including seam height, body hook, cover hook, overlap, seam thickness, countersink depth, and body hook butting and wrinkle rating.

It offers the option of connecting directly to the filling line, with a sample of cans automatically diverted to the machine for seam analysis, or can be fed with cans manually. In either case, the cans are then either held for additional inspection or returned to the production line.

CMC-Kuhnke also highlights the handling system of the Mars-XTS, developed for transporting filled cans through the measurement stations without damaging or affecting the product.

After filling and sealing, Krones offers one further safety-check for glass bottles, with a system devoted to detecting the potentially disastrous problem of glass fragments and other foreign bodies inside the containers.

With a suitably investigative name – the Linatronic 774-FBI – the unit operates on up to 72,000 bottles an hour. It uses two camera modules, each of which take three separate images at different angles, to detect particles that are transparent, suspended in the beer, or lying flat to the base of the bottle.

Label Mates

When each container is filled with the correct amount of beer and securely closed, there are systems for the end of the line to verify the labels and branding of each can or bottle.

It’s not just a branding issue – what’s important for fillers is to make sure that the correct containers have been used for the relevant product. Fill a can designated for a triple-hopped IPA with a smoked porter and you’ll startle a beer afficianado – but if a drinks manufacturer producing both soft drinks and alcoholic drinks at the same facility fills the wrong can, there could be legal ramifications.

UK-based Sencon explains that cans from previous batches can get stuck on the line and then swept up into a new batch, resulting in a can being filled with contents that does not match its label. The worse-case scenario of alcohol going into a soft drink-labelled can would be a serious retail incident – but more often it results in whole pallets being held up for inspection and sorting, costing time and money.

To address the problem, Sencon developed the LVC180 Label Verifier specifically for cans, which unlike glass bottles arrive with their labelling already printed, hence the need for a slightly different approach than glass bottle filling operations.

It’s suitable for the can manufacturers as well, but at a filling operation can be used to detect rogue cans in a batch prior to filling, or after filling and seaming has been completed.

A key advantage of the system is its twin-sided, 85-degree view of each can, much wider than comparable systems, adds Sencon. This in turn can help to reduce HFIs and false reject rates, improving productivity.

The system can also be used as an entry-level decoration inspection unit too, says Sencon, and notes that it is designed to be very simple to operate, requiring three button pushes to learn a can label and start work.The issue of decorating accuracy is another area to check, and although packaging manufacturers and label printers have their own quality control systems in place, fillers can double-check packaging for issues such as colour-matching – key for brand identity – as well as printing errors and barcode verification.

For cans, Sacmi’s Elioscan system uses ultra-high-resolution 5-megapixel cameras in combination with bespoke illumination designed to counter the potential problems of imaging and analysing reflective surfaces. It comprises four colour cameras to pick out variations in colour shades, minor defects such as ink stains and discoloured areas, and read barcodes.

The Italian company also supplies the LVS360 vision system, designed specifically for quality control of labelled bottles. The system looks at the presence and positioning of each label, identifies rogue bottles within a batch, and detect more minor issues such as unglued label corners, labels applied in ‘flag’ format, bubbles, spots, wrinkles and tears – as well as, again, being able to read the barcode.

And for brewers using branded crown corks, KHS developed the Innocheck CLI, designed to verify that the logo on the cap of each bottle correlates to the product inside. Using an LED lighting unit and a high-precision lens system, the machine also checks for soiled or scratched caps. And it’s suitable for a wide range of cap and closure types, so any brewers adding an extra element of branding to their can ends will be able to use the system as well.