Between April 26th and 27th the conference Kunststoffe + Simulation 2016 took place. SIGMA Engineering GmbH partnered with Momentive Performance Materials and CVA Silicone to explain the virtual and real production of the design article Ursula. SIGMASOFT® Virtual Molding optimized geometries and process parameters, helped to understand problems in the material selection process and to make sound decisions for the part production. Partnering with Momentive Performance Materials and CVA Silicone, SIGMA Engineering, represented by Vanessa Schwittay, gave a presentation on the topic “Reality and Simulation – Physical and Virtual Production of Ursula”. The presentation demonstrated how SIGMASOFT® was used to support the material selection of the design article “Ursula”, an LSR mesh to carry bottles.

The article, named after Ursula Andress (the first bond Girl), has a long flow length and an interlaced geometry. These characteristics require a material with high stability in rheological properties and curing kinetics, as well as an elaborate tempering and cold runner concept.

SIGMASOFT® Virtual Molding was used to select the best material for this application. Two LSR 70 Shore A grades where compared. It was observed that the flowability of the first material was lower, so that only 90% of the cavity was filled. The second grade in comparison, allowed a 100% of filling. Thus the Siloprene LSR 2670, from Momentive, was selected for production.

The analysis of the curing degree during part filling revealed the reason for the different behavior: The first material showed a curing degree of over 15% already during filling, what impaired a proper flow; the second cured below 5% during filling, allowing a smooth filling.