Smart Molding International 2-2025

28 smart_molding international 2/2025 molding technologies of energy consumption by up to 5 per cent is possible.” The servo-hydraulic SmartPower machines from the WITTMANN Group also operate with KERS. In this series, the combination of fast-responding servo motors with powerful constant displacement pumps is the standard. For the injection molding process, this means maximum speed and precision of the machine’s movements with simultaneous minimal energy consumption. Specialized dryer solution for PETG On the day of our visit, small, slender bottles produced inside a 16-cavity mold are running off the clock-out belt of an EcoPower 300 injection molding machine. Anyone unfamiliar with the material would take it for glass. In reality, it is PET. “PET looks like glass, but it does not break when it falls down”, explains Gula, which is why this material is playing a more and more significant part in cosmetics packaging. Twelve years ago, Bell was the pioneer in this field. “We were the first cosmetics producer to manufacture bottles for mascara and lip gloss from PET”, says Gula. Today, primarily PETG is processed, a glycol-modified variant offering a particularly high degree of transparency and impact strength, and simultaneously excellent processing attributes. With their standardized universal screws, the SmartPower and EcoPower machines deliver first-class injection molding results. “Only the drying process presents a special challenge for this material”, Gula discloses. While normal PET is dried with temperatures around 160 °C, PETG requires significantly lower temperatures between 60° and 70 °C. “So, we have specially fitted the WITTMANN Drymax dryers for our customer Bell with a cooling device”, reports Bogdan Zabrzewski. In this customized solution, it was of special importance for Bell that the cooling can be switched on or off as required. For the dryers are being used flexibly for other materials, too. “The Drymax from WITTMANN has absolutely convinced us”, says Gula. “We are reaching a dew point of -67 °C with it. This has not been achieved so far by any other dryer model.” Zabrzewski explains the high performance of the Drymax dryer with the use of two desiccant cartridges. “The dryers deliver process air continuously, and drying air of constant high quality.” Thanks to countercurrent regeneration, the dryer also stands out by its extremely energy-efficient operation. Machines with short delivery times Bell’s customer base is heterogeneous. In addition to long-standing customers, who place their orders well in advance and invariably for large quantities, there is a daily inflow of many short-term orders involving relatively small batch sizes. What is more, every national market sets different requirements, all of which has led to a very large number of active molds and frequent mold changes. “Elastic production” is the term used by Waldemar Gula to describe this great flexibility required from Bell every day. Production planning is getting even more complex due to the innovation cycles becoming shorter and shorter. “Often a completely new packaging design emerges after just one year”, Gula reports. Here, the in-house mold making shop helps the company to keep up with Production inside a 16-cavity mold