Material Drying
1 views
PET startup pre-drying
Problem Phenomenon
Starting the machine after two days of shutdown, the first batch of preforms are all scrapped for white haze
Cause Analysis
During the shutdown, the chips and equipment absorb moisture, and the machine is started without re-drying, so wet material is directly molded; during on-site troubleshooting, verify item by item according to this mechanism, and avoid blindly adjusting the machine based only on experience
Solution
Before startup, re-dry the material for more than 4 hours and test the moisture content; first empty the residual material in the barrel; mass production begins only after the first article passes inspection; after adjustment, take consecutive samples to verify the effect, and resume mass production only after confirming stability
Key Takeaway
Restarting after a shutdown must re-establish the drying state; after confirming effectiveness, solidify the parameters and practices into the work instruction to prevent recurrence; include this case in the defect archive as a troubleshooting reference for subsequent similar problems
Was this helpful?
0 people found this helpful
Thank you for your feedback!