Material Drying
2 views
PARA Burnt Trapped Air
Problem Phenomenon
PARA products are burnt at the end and melt-converging areas; during high-speed injection, gas is compressed to high temperature and carbonized, concentrating in poorly vented areas.
Cause Analysis
Poor mold venting; too-high molding temperature; too-high injection speed; too-high injection pressure; too-high raw material moisture content; multiple factors superimpose to compress gas with adiabatic heating.
Solution
①Add vent holes and vent grooves; ②Reduce barrel temperature and injection speed; ③Reduce injection pressure; ④Fully dry the raw material.; after adjustment, continuously sample to verify the effect, and resume mass production only after confirming stability
Key Takeaway
PARA burnt troubleshooting must cover the five factors of temperature, speed, pressure, moisture and venting; the venting design of high-speed processes must be strengthened; systematic troubleshooting is superior to single-point adjustment.
Was this helpful?
0 people found this helpful
Thank you for your feedback!