Cooling accounts for 80 percent of the molding cycle and is a crucial phase in successful molding. Critical dimensions, warpage, and surface finish are all affected by cooling conditions, and poorly cooled parts increase cycle time, dimensional problems, and wastage.
Flow problems manifest themselves in a variety of ways, including overpacking, insufficient packing, and visual defects.
Molding problems manifest themselves in many ways, from visual defects like burn marks, to physical problems such as delamination. This category of defects covers that broad group not caused primarily by cooling or flow problems.
Warpage occurs when there are variations of internal stresses in the material caused by a variation in shrinkage.