Injection Molding
4 views
PA6 '2079851475616104452 uneven shrinkage
Problem Phenomenon
Large shrinkage differences in different directions of the same part, unstable dimensions.
Cause Analysis
Crystallization orientation anisotropy + wall thickness differences; shrinkage differs between flow/transverse directions; during on-site troubleshooting, verify item by item according to this mechanism, and avoid blindly adjusting the machine based solely on experience; during troubleshooting, confirm item by item around key factors such as uneven shrinkage and orientation to avoid misjudgment.
Solution
①Optimize wall thickness uniformity to reduce differential shrinkage; ②balance holding pressure and time, taking into account both feeding and stress; ③optimize gate position and size; ④ensure uniform mold temperature; ⑤use CAE analysis to assist decision-making when necessary.
Key Takeaway
PA6 uneven shrinkage='orientation and wall thickness': the anisotropy of crystalline materials is the root cause; uniform wall thickness and gate optimization are the main line; 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!