Pack Module

The Pack analysis module simulates the conditions inside the cavity before part ejection.

SOLIDWORKS Plastics simulates the material’s phase change from fluid to solid and the volumetric shrinkage that results. It also simulates the build-up of stresses, which later influence the molded plastic part’s final dimensions and warpage. Pack results are required to run a Warp analysis.

Pack analysis simulates the process where an injection machine applies pressure to the injection system to cause additional material to enter the cavity as the part shrinks and freezes. To control the switch-over from Fill to Pack, you can specify a time value or a cavity fill percentage in the Pack Settings PropertyManager. You can also use these settings to create a pressure profile rather than using a constant packing pressure.

Results from a Pack analysis include:
  • Distributions of temperature time histories at every location of the part, which allows the prediction of hot spots, gate freeze, and cycle time
  • Distributions of pressure, residual stress, and volumetric shrinkage
  • Information about the required clamping force and the time-evolution of the part mass as the material density changes.

From the Fill and Pack analyses, you can estimate the optimal process conditions, such as filling time, injection pressure profile, pressure holding time, melt temperature, and mold temperature. In addition, you can gain insights about the optimal mold design parameters such as gate location, gate design, and runner design.

Pack Analysis Steps

1 Define the process parameters:
  • Pack time, pressure profile
  • Pure cooling time

CAD geometry of a part
2 Create the mesh and select materials

Surface mesh

3 Run the analysis

Result plot of volumetric shrinkage at end of packing