They are mold closing, filling, packing, cooling, mold opening and ejection as shown here. Cooling Time is a major fraction of the total cycle time. In this example, the cycle time is 35 seconds.
Filling requires just a few seconds.
A slight increase in pressure occurs when the mold is closed. When gate freeze off occurs, melt can no longer be forced into the cavity and the pressure drops. When the part cools below its glass transition temperature, the mold can be opened and the part ejected. At this stage, the pressure drops to ambient level. Two curves are shown.