The temperature of the injection molding machine is controlled during the complete cycle.
As the cooling system is always active, the length of the cooling time is not clearly defined.
During the filling, the melt moists the cavity only partly.
This is the reason for the definition of the cooling time from the end of injection until ejection.
That means, the cooling time equals the packing time (green line) plus the residual cooling time (blue line in the time-pressure-diagram).
This glossary of plastic industry is provided by PLEXPERT Canada Inc.