411 REFERENCE · Wikibooks
Plastics Molding & Manufacturing/Injection
Reference material by Wikibooks contributors. This retains its source identity and is not 411 news reporting.
First, the injection system will inject roughly about 80 % - 95 % into empty cavity mould as fast as it could.
The remaining 20 % to 5 % are injected slowly because thermoplastics shrinked when they cooled to prevent any void or bubbles.
Finally, clamping system hold the mould until the gating freezes off.