In hot runner systems heater bands are used. This is to bring the temperature inside of the melt channel up to the wanted process temperature and keep it constantly at this level.
The hot runner system consists mostly of one manifold and one or more hot runner drops.
In order to control the temperature a sensors are used in combination with PID-Controller.
The aim is to reach a homogeneous temperature distribution within the melt channel.
This glossary of plastic industry is provided by PLEXPERT Canada Inc.