Günther Heisskanaltechnik successfully relies on Virtual Molding

Company: Günther Heisskanaltechnik GmbH
SIGMASOFT® user: since 2010
Main application: Dimensioning and optimization of hot runner systems
License: Thermoplastic (Floating)
Website: www.guenther-hotrunner.com

To increase the efficiency in the injection molding process, the usage of hot runner systems is an established medium. Cycle time reduction, increase of the number of produced parts and scrap reduction are only few goals, which should be achieved by the use of hot runner systems. The Günther Heisskanaltechnik GmbH supports their costumers since 1983 to achieve these goals. Since 2010 Günther Heisskanaltechnik utilizes SIGMASOFT® Virtual Molding for the dimensioning and optimization of hot runner systems – already before production. A well attuned team of process- and application engineers use a SIGMASOFT® floating license to detect possible problems of the hot runner system before production and fix them before the serial production. This saves iterations at the hot runner and in the end time and money for the customer. Dipl.-Ing. Marco Kwiatkowski confirms that there are in practice no returns of hot runner manifold systems anymore.

SIGMASOFT® is used for the calculation of pressure loss in hot runner systems and the heat distribution of hot runner manifolds and –nozzles.

The heat calculation shows, if the designed hot runner systems are dimensioned in the best way concerning the temperature distribution. Particularly for special manifolds a calculation beforehand is very important, because the company Günther realizes many applications for technical plastics, which often only have a small processing window. The present case shows a thermal calculation of a manifold system with the corresponding temperature distribution after a multi cycle analysis. On the left is the initial state, on the right the – via Virtual Molding – improved version. An essentially better homogeneity of the temperature distribution of the manifold system was achieved through the optimization. The calculated temperatures of the optimized version show a maximum variance of 2 °C in comparison to the measured temperatures.

In the same way the pressure loss calculation is conducted: through calculations before the production, it is possible to ensure, that the pressure loss in the system is not too large. The calculated pressure loss gives information about the ideal dimension of the hot runner systems. The demand here is a maximum pressure loss of 500 bar in the system. For an injection molding machine with 2000 bar, this means, that for the filling of the cavity, after subtracting the pressure loss of the plasticizing unit and the machine nozzle (ca. 300 bar), there are at least 1200 bar available. Low pressure consumption in the manifold system leads in the best case to a production on a next smaller machine and helps to sensibly plan capacities and resources.

While a few years ago assessments of the pressure loss with simple simulation tools were accepted by the customers, current precision equipment require an exact and reliable prediction of the pressure loss, especially for sophisticated materials. Günther Heisskanaltechnik exercises this accuracy for the pressure loss calculation as well as for the thermal dimension and reduces modification loops significantly with simultaneous increase of the customer satisfaction. A subsequent optimization and revision of the delivered systems is no longer required. The saving of optimization loops and post-treatment creates additional capacity in the product development and increases effectively and perceptibly the economy.

Beside the software Günther relies on the know-how of the SIGMASOFT® team consisting of engineers with a specialization in the field of plastics technologies. “The support of SIGMASOFT® is exemplary, there is always someone on hand with help and advice – be it a question about the process or about the software”, says Dipl.-Ing. Marco Kwiatkowski asked about the customer support.

Left: Not optimized manifold with distinct temperature differences. Right: With Virtual Molding optimized manifold with homogeneous distribution.