Extrusion & Post
1 views
HDPE film poor transverse tear
Problem Phenomenon
The transverse tear strength of the film is low, unbalanced with the longitudinal performance.
Cause Analysis
Insufficient blow-up ratio makes the transverse molecular chains insufficiently stretched; uneven discharge from the die gap also causes dispersion of transverse performance.; when troubleshooting on site, verify item by item according to this mechanism, and avoid blindly adjusting the machine based only on experience
Solution
①Increase the blow-up ratio to 2~4 times; ②balance the biaxial draw ratios; ③check the discharge uniformity of the die gap; ④adjust the resin structure if necessary.; after adjustment, continuously sample to verify the effect, and resume mass production only after confirming stability
Key Takeaway
The balance of transverse and longitudinal performance depends on the matching of blow-up ratio and draw ratio; biaxial testing is the direct method to verify the balance.; after confirming effectiveness, solidify the parameters and practices into the work instruction to prevent recurrence
Was this helpful?
0 people found this helpful
Thank you for your feedback!