Extrusion: Simulation Software Permits Die Optimization

Known primarily for developing software to optimize injection mold and runner design, Sigma Engineering will give attendees at the K 2019 show a look at its developments in simulation software for extrusion die design. 

As Sigma explains, melt inside an extrusion die is a lot like  flow behavior inside a hot runner of thermoplastic or inside the cold runner of elastomer applications. In an extrusion die, moreover, the temperature distribution inside the die alloy, as well as the geometry of the flow channel, have significant influence on the flow behavior. 

Simulation helps to identify dead spots, excessively long dwelling times in the die or high pressure losses even before the die is built. In this way, tool changing costs and excessive trial-and-error runs to find the optimum configuration are reduced. The development of a new extrusion line gets faster, cheaper and more predictable.

Sigma has found that with Sigmasoft Autonomous Optimization, flow channels of the extrusion die are automatically optimized within hours, “dramatically improving” the quality of the extrudate. To achieve this goal, geometrical degrees of freedom for the extrusion die’s flow channel are defined inside the software. The software then autonomously determines the ideal geometry for a dimensionally stable extrudate.

“The software currently available on the market helps to calculate the temperature distribution inside the extrusion dies. However, with the help of our software and the included Virtual DoE, users will be able to automatically optimize their extrusion die finding a geometry which allows for an extrusion with homogenous velocities,” explains Timo Gebauer, CTO at Sigma. With the optimized velocity profile inside the extrusion die the deformation of the extruded profile will be minimized.