Extrusion International 5-2025-USA

71 Extrusion International 5/2025 PERIPHERY Inline Spectroscopy Closes a Major Data Gap in Polymer Extrusion For data-driven process control and optimization, one key ingredient is essential: comprehensive and continuous data. While many process parameters in extrusion are already captured automatically and in real time, a signi cant gap remains when it comes to product-speci c data. These are typically obtained through manual sampling and laboratory analysis, making them discontinuous, time-delayed, and certainly not available 24/7. Labs often use spectrometers, but they analyze off-spec samples – cooled and solidi ed (e.g., injection-molded) materials – which introduce delays of several hours while production continues at full speed. (Picture 1) T his discontinuity makes real-time process and quality control im- possible, creating a barrier to digitali- zation and AI-based data evaluation. Moreover, it can lead to undetected short-term events in the extruder, unnecessary waste, increased costs, and, in some cases, reputational damage due to product rejects. The root of this gap lies in the extreme conditions within an ex- truder, where conventional Quality Control and spectroscopy systems fail. High temperatures and pres- sures are standard, and traditional ber-optic probes are not designed to operate under such conditions. ColVisTec AG, based in Berlin, has taken on the challenge of making the extrusion process transpar- ent from the product/production side by developing a spectroscopy- based inline technology tailored for the extreme extrusion environ- ment. This is enabled by specially engineered ber-optic probes fea - turing sapphire windows, designed to withstand the harsh conditions in most extruders – up to 752 °F (400 °C) and 3,625 psi (250 bar). The UV/Vis, NIR, and Raman in- line spectrometers from ColVisTec quite literally shine a light into the "black box" of extrusion, revealing what was previously hidden – en- suring 100% transparency and con - trol during production. (Picture 2) Whether in traditional polymer compounding, mechanical or chem- ical recycling, reactive extrusion, or hot melt extrusion, inline spectros- copy delivers real-time data and im- mediate visualization of what’s hap- pening in the melt. Depending on the chosen meth- od, users receive continuous prod- uct-related information: Picture 1: ColVisTec Probe in a Twin Screw Extruder (see marking) – Image Courtesy of KraussMaffei Extrusion GmbH, Germany Picture 2: ColVisTec CVTtrend Inline Software Showing in Real-Time Variations of Recipe