Extrusion & Post
1 views
PET sheet transverse streaks
Problem Phenomenon
Periodic transverse lines appear on the sheet, similar to water ripples; thickness measurement is normal
Cause Analysis
Transverse lines are an inherent defect source of the calendering process: the speed difference between two calender rolls forms imprints; when the speed regulation accuracy of the three rolls is insufficient, transverse lines appear periodically; during on-site troubleshooting, verify item by item according to this mechanism, and avoid blindly adjusting the machine based only on experience
Solution
① Improve the speed regulation accuracy of the three-roll calender; ② check the roll system transmission clearance; ③ optimize the haul-off speed matching; after adjustment, continuously sample to verify the effect, and resume mass production only after confirming stability
Key Takeaway
PET sheet transverse lines point to roll system speed accuracy; upgrading the speed regulation system can cure such periodic defects better than adjusting the process; after confirming effectiveness, fix the parameters and practices into the work instruction to prevent recurrence
Was this helpful?
0 people found this helpful
Thank you for your feedback!