Seeing Red (in a Good Way)

Thermal imaging involves the thorough examination of key heat markers that register as infrared light. Image courtesy of Yoran Imaging.

Thermal imaging technology can revolutionize heat seal inspection – and optimize food and beverage packaging production lines.

By Dan Ram,  Chairman of Yoran Imaging

On food and beverage (F&B) production lines around the world, automation has come a long way. Machines are now efficiently and precisely handling tasks previously performed less perfectly by humans. Examples of this can be found both upstream and downstream, in everything from initial processing, sorting and conveying to end-of-line quality control elements like X-ray scanner detection and checkweighing.

While all this is undoubtedly encouraging, there remains one question to companies across a broad range of food and beverage categories:

What about your heat seal?

Sometimes facts seem ridiculous when spelled out in black and white. To that end: It’s 2024, and over 95% of food and beverage companies utilizing heat sealed packaging are testing those seals by … pulling one off the line occasionally and looking at it.

Heat sealing is an incredibly intricate, scenario-specific step along modern packaging lines. Anything from sealing temperature and applied pressure to a package’s individual sealing area and angle can affect a mission-critical element – proper package closure – and lead to discarded product, disgruntled consumers and disparaged reputations. There’s a lot that can go wrong – and a lot of difficult-to-discover reasons why.

Well, if you’re inspecting via manual sampling, that is.

The technology now exists not only to automate filling and heat seal inspection – substantially increasing both accuracy and potential production speeds – but to capture and report digestible data pertaining to equipment performance. Thermal imaging inspection brings the potential not only for 100% packaging inspection, but also for comprehensive insight that optimizes production by catching negative trends early, promoting predictive maintenance, avoiding wasted products or packaging materials, and generally doing what the best manufacturing systems do: keep the line moving.

Let’s explore the benefits of incorporating thermal imaging inspection for heat seal processes on food and beverage packaging lines.

Thermal imaging technology can pinpoint a precise portion of the sealing process that may be experiencing a failure. Image courtesy of Yoran Imaging.

Heatseeking precision

Before continuing, let’s define the various F&B packaging categories that frequently utilize heat seal closing, and dive a little deeper into how thermal imaging technology works.

An exceptionally wide range of packaging types regularly utilize heat sealing. Pouches, sachets, stick packs. Flow wrap bags (think potato chips) and doypacks (think stand-up pouches, like those used for certain candies). Blisters and tubes. Cups, trays, and even some cartons. You name it, they heat seal it. Notably, these packages come in a vast array of shapes, sizes and substrates, all parameters that impact filling and heat sealing processes.

So how, exactly, does thermal imaging work? In layman’s terms, the technology involves the thorough examination of key heat markers that register as infrared light. The analytical technology has origins in the defense sector, where its benefit is particularly useful for night vision gear. It has since been deployed to various high-leverage sectors including semiconductor fabrication, electronic optics, electronics, image processing and radiometric analytics.

Most recently, the new James Webb Space Telescope scans the cosmos with high-resolution infrared cameras to explore previously unseen depths of space – including elusive areas from which visible light cannot reach us. Among other revelations, this has provided glimpses of the nascent universe in the period immediately following the Big Bang.

When trained on closer items, the technology can be stunningly meticulous. For heat seal packaging inspection, it can provide sophisticated, value-added monitoring for an intricate, multifaceted process. It’s “automated quality control plus” – extreme emphasis on the “plus.”

Gatekeeping isn’t the only step essential to sufficient quality control; so is the overall health of the production line. Unfortunately, due in varying degrees to technological hurdles and economic infeasibility, an historic lack of information captured at heat sealing stations has left line operators blind to valuable equipment diagnostic data.

Simply put: You don’t know what you don’t know – and what you don’t know can indeed hurt. Unknown factors can create anything from a cumbersome production bottleneck to packages that literally come apart at the seams.

If the devil is in the details, thermal imaging-enabled data metrics mining can be a godsend. When converted into digestible information displayed on operator HMIs, the technology can pinpoint a precise portion of the sealing process that may be experiencing a failure. As a result, detrimental trends can be recognized and reconciled at their inception rather than their unenviable conclusions: line stoppages, rejects and reworks.

In this fashion, thermal imaging-enabled data metrics mining embodies the very essence of predictive maintenance, which requires not only foresight but insight; in a process as multifaceted as heat sealing, operators must not only know that a failure is on the horizon, but exactly what aspect of heat sealing needs to be rectified to prevent that undesirable outcome. Operators get to fix minor issues with ample time to spare, rather than major problems with little or no warning.

The topline benefits are obvious. Automated processes more accurately identify sealing integrity issues even while yielding expedited line speeds and, when combined with the additional equipment uptime gained by inline course corrections, the result is more products produced over a given period. Time is money, and products are profits.

Other benefits are less readily apparent. For one, a smart heat seal process also boosts food and beverage companies’ ability to stay atop an issue that has transitioned from megatrend to mainstay: sustainability.

Calibrating packaging lines to handle new materials is complicated and time-consuming. It took decades for equipment lines to perfect the usage of conventional packaging materials. But we don’t have decades to incorporate the various next-generation materials necessary to move toward a more sustainable, circular economy. We have a few years, at most, to iron out the complicated, mission-critical wrinkles.

As is often the case, the baseline challenges branch off into myriad other ones. Newer, more sustainable packaging materials tend to require a lower heat seal temperature, and can react differently to pressure. These issues must be addressed and optimized not once, but for each distinct substrate, product type, and packaging size and shape. Without a tightly monitored sealing process and its corresponding mined data, perfecting package-specific best practices in a condensed timeframe is all but impossible.

The conclusion is clear: sampling simply isn’t good enough anymore. Technological advancements have exponentially improved manufacturing processes up and down modern food and beverage production lines. The time has come for heat sealing inspection to join this ever-growing, progress-centric roster.

About the Author

Dan Ram is Chairman of Yoran Imaging, which utilizes cutting-edge thermal imaging technology to revolutionize the filling and heat-sealing process on packaging lines. Drawing upon more than two decades of thermal imaging inspection experience, the company’s solutions provide non-invasive, 100% in-line inspection combined with production-optimizing data collection and analysis. Learn more at www.yoran-imaging.com.