Molds & Tooling
2 views
POM product dimensions too large
Problem Phenomenon
Product dimensions are systematically too large and out of tolerance, the shrinkage is significantly lower than expected, and dimensions fall back after adjusting holding pressure.
Cause Analysis
Excessive holding pressure or too long time causes excessive feeding in the cavity and higher density, reducing shrinkage; too high mold temperature also delays crystallization and lowers the shrinkage.; during on-site troubleshooting, verify item by item according to this mechanism, and avoid blindly adjusting the machine based only on experience
Solution
①Optimize the holding pressure and time curve; ②appropriately lower mold temperature; ③check mold compensation with measured shrinkage; ④re-measure dimensions after stabilizing the process.; after adjustment, continuously sample to verify the effect, and resume mass production only after confirming stability
Key Takeaway
Oversized dimensions point to excessive feeding or high mold temperature; POM shrinkage is sensitive to holding pressure, and dimensional debugging should be based on measured shrinkage.; 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!