◆ Common Causes
- •Melt temperature too high (thermal degradation)
- •Excessive residence time
- •Contamination from previous resin
- •Damaged screw or barrel
- •Flame retardant decomposition
◆ Solutions
- ✓Lower melt temperature
- ✓Shorten cycle time
- ✓Thorough purging
- ✓Inspect screw and barrel
- ✓Equalize hot runner temperature
◆ Resin-Specific Notes
ABS
Yellowing/browning above 260°C.
FR Grades
Check decomposition temperature of flame retardants (especially halogenated). Mandatory.
PA
Hydrolytic discoloration from moisture.
Keep using it on the floor — your diagnosis history and machine conditions accumulate in the app.
Free 5 diagnoses when you sign up
This content is a field-reference summary. Final judgment requires on-site engineer verification.