Extrusion 3-2021

Material Handling – Case Study 25 Extrusion 3/2021 GRAVICO – The Perfect Ally for Extrusion T he attention to dosing in the extrusion process has led Contrex to develop innovative solutions that guarantee high dosing accuracy, flexibility and perfect materials mixing. Contrex is a company of the Moretto Group, it has been deve- loping solutions for blown film, profiles, sheets and pipes extru- sion for over 40 years. Case History : In Germany two dosing units for the extrusion of PET profiles have recently been installed. The project comprised the realization of a loss-in-weight dosing system suitable for PET treatment with a dosing range from 50 grams/hour to 250 kg/hour. The customer needed to produce a new product serving two starved-mouth extruders, dosing very low percentages of mate- rial, masterbatch and additives. The customer required an effec- tive dosing system assuring maximum production flexibility and the certainty of dosing the components correctly, communicat- ing simultaneously with the extruder. A strict need concerned the treatment of PET that demands temperatures up to 180 °C. The solution is GRAVICO, the innovative continuous loss-in- weight multicomponent dosing system with automatic weight/meter adjustment that can be installed in all 24/7 pro- duction plants. An accurate, self-adaptive dosing system designed to handle up to six components allowing a wide number of configurations. GRAVICO is EASY TO PROGRAM thanks to the menu placed on a 22-inch touch view interface allowing the operator to auto- matically manage the production parameters in all production process’ stages. It acts IN ADVANCE verifying that the doser adapts to the performance and the result of the finished prod- uct; DURING the extrusion process, controlling it and acting on its speed through the thickness and/or dimensional control of the extruder. A real synchronism among doser, extruder, haul- off and finished product. GRAVICO ensures HIGH PRECISION by weighing each material and getting the same result over time thanks to the algorithm based on the filtering of 1000 weighed per second, one of the exclusive features that characterized this project. A precise dos- ing system, synonymous with quality in the extrusion of the finished product. 24/7 production plants that do not allow downtime. GRAVICO meets this need with on-the-go production changes. The entire stainless steel construction allows its application even in de- manding sectors such as food or medical. The total absence of material stagnation zones ensures high quality production ac- cording to the desired standards. A reliable, modular and easy to use machine. Thanks to the im- plementation of the OPC UA protocol, it complies with Industry 4.0 principles. Moretto and Contrex systems are the result of a continuous investment in technology, automation and re- search. Highly competitive equipment, energy-efficiency soluti- ons that meet the real needs of all plastic transformers, whether they are involved in the world of injection, extrusion or PET processing. Extrusion professionals know the importance of adopting equipment that guarantees the correct process control. Dosing the exact amount of material, assuring process stability and knowing how to “control” the extruder are fundamental requirements to ensure high quality standards and eliminate any risk of hidden costs and material waste. Moretto S.p.A. www.moretto.com Contrex S.r.l. www.contrex.it