SIGMASOFT® – Multicomponent Mode – More than just the sum of all things

 (c) SIGMA Engineering GmbH

Figure 1: Mold temperature distribution during filling of thermoplastic component

Figure 1: Mold temperature distribution during filling of thermoplastic component (c) SIGMA Engineering GmbH
Figure 2: Temperature distribution of mold during filling of the elastomer sealing (c) SIGMA Engineering GmbH
Figure 3: Pressure distribution in the elastomer sealing during filling (c) SIGMA Engineering GmbH
Preview_1 (c) SIGMA Engineering GmbH
Preview_2 (c) SIGMA Engineering GmbH

The spirit of achieving the most with the least amount of steps necessary – efficiency – has not halted before the injection molding process. Technical parts integrating multiple process steps, components and functions have become a daily task to manage by qualified engineers.

Each component has its unique requirements in processing – uniting those requirements in one overall process requires an in depth understanding of the influences on the part quality.

The SIGMASOFT® Multicomponent Mode will help you answering typical questions like:

  • What is the overall process time to finished part?
  • For thermoplastic applications: Does one component get re-melted during over molding and  am I to expect defects on the surface?
  • Where do I have potential to optimize my process times?
  • How does the fiber orientation of the insert influence the overall part shrinkage and warpage?

The best out of both worlds – Bringing together Thermoplastic materials with Elastomers

In a practical example we have an oil pan (thermoplastic material – PA 6) which is molded in a first shot. In the second shot a sealing (elastomer material – natural rubber) is injected. Both shots are not only happening in the same mold but simultaneously in the running process.

In this case the first step is to understand the thermal situation in the mold. When we talk about thermoplastic processes we tend to have hot melt (200 °C +) injected into a cool mold (100 °C and less). For elastomer injection it is the other way around (cold melt – supplied by a cold runner) injected into a hot mold.

To bring those two opposing processes together in one mold we at first simulated the complete injection molding tool (including tempering channels, bushings, insulations etc.) in the unique SIGMASOFT® Multicycle analysis to get the mold in a thermal steady state (no more change in temperature expected).

When the first shot is finished the first component is transferred into the second cavity where the sealing (NR) is being injected. The video shows the interaction of the first component with the (hot) mold needed for injecting the rubber.