There were a lot of uncertainties surrounding Extreme’s molding process before they used Moldex3D – What will the fill time be? Can our press generate the needed sprue pressure? How much clamp force will we need? Is the shot size appropriate for the barrel? To reduce these uncertainties, Extreme decided to look at Moldex3D’s solutions that can help provide greater confidence prior to actual manufacturing.
- Find the appropriate venting locations
- Find the appropriate coolant temperature
- Obtain the effective packing time in order to meet the specification of shrinkage
- Find the areas requiring venting
- Minimize the part shrinkage
- Optimize the cooling time and cycle time
Extreme chose Moldex3D to help eliminate uncertainties arising from the molding process. They would like to utilize Moldex3D to find the area where additional air venting is required, the press needed, the maximum clamp force, reasonable filling time and predict product warpage before the mold trials.
From the filling /packing simulation, they knew the filling pressure was well below the maximum, the maximum clamp force was acceptable, and the maximum shear rate was below the limit. Therefore, they conclude that the press was able to meet their needs (Fig. 1).
Fig. 1 From Moldex3D filling /packing simulation, Extreme knew their press was acceptable.
Moldex3D simulation results of the melt front also helped Extreme make educated decision as to where to vent and also drive the tool design right from the start. Thus, they didn’t have to wait till short shots occur in the first sample to make adjustments or corrections (Fig. 2).
Fig. 2 Moldex3D’s short shot analysis correlates to the actual result.
Extreme then changed the coolant temperature, which led to much lower average surface temperature. They simulated 3 different coolant temperatures and observed their influence on the part surface temperature and shrinkage. As a result, they found at 117℉, the shrinkage meets the required specification (Fig. 3).
Fig. 3 According to the simulation of 3 different coolant temperatures, 117 F degrees was found the most desired.
Next, Extreme increased the packing time. They simulated 4 different packing times and observed the shrinkage results. It was found 17s could be a good compromise (Fig. 4).
Fig. 4 The packing time of 17s was found a good compromise for shrinkage.
Moldex3D simulation software provides tools to examine potential problematic areas in parts and helps Extreme make well-informed decisions. Extreme used the information obtained from simulation to optimize cooling and determine cycle time. This also helped them avoid costly mold repair and reworks, and the simulation can further guide future designs with confidence in accuracy.