Extrusion & Post
8 views
PVDF Extrusion Melt Fracture
Problem Phenomenon
Sharkskin on the extrudate.
Cause Analysis
Excessive die shear; low temperature and small gap aggravate it.; During on-site troubleshooting, verify item by item according to this mechanism, and avoid blindly adjusting the machine based solely on experience; This mechanism has been repeatedly verified by industry materials, and it should be confirmed first during troubleshooting
Solution
①Increase the die temperature; ②widen the gap; ③reduce speed; ④optimize the formulation.; After adjustment, take consecutive samples to verify the effect, and resume mass production only after confirming stability; Change only one variable at a time and record parameter changes, so as to locate effective measures
Key Takeaway
Melt fracture is shear instability.; After confirming effectiveness, fix the parameters and practices into the work instruction to prevent recurrence; Include this case in the defect archive as a reference for troubleshooting similar problems in the future
Was this helpful?
0 people found this helpful
Thank you for your feedback!