Cold runner systems should be designed with equal sizes and flow lengths to all cavities for a balanced overall process. In this lesson we will explore the implications of an unbalanced runner system and the modification necessary for artificially balancing cold runners.
This lesson covers why unbalanced runner systems have unbalanced filling behaviors and pressure spikes, the steps needed to artificially balance a runner system, how to achieve optimal filling patterns, injection pressures, and cooling behaviors, and why adding flow length may balance a fill pattern but create shear-related imbalances.