Processing Machinery
1 views
PE Pipe Surface Roughness and Black Specks
Problem Phenomenon
The outer surface of PE pipes is rough and dull, or black specks and impurities appear on the surface/inside; drinking water pipes and gas pipes are directly rejected.
Cause Analysis
Surface roughness is mostly caused by low melt temperature and poor plasticization, poor raw material quality or high regrind ratio, and screw and die contamination and wear; black specks come from raw material contamination or carbonized material shedding from the barrel and die head, and non-standard startup and shutdown procedures cause the material to be heated for a long time and carbonized.
Solution
①Optimize the temperature settings to ensure full plasticization; ②use qualified PE resin and control the regrind ratio; ③regularly clean the screw, barrel and die; ④standardize the startup and shutdown procedures, emptying or lowering the temperature before shutdown; ⑤check the screen pack condition and strengthen raw material cleanliness management.
Key Takeaway
Troubleshoot PE pipe appearance in the order of 'plasticization → raw material → cleanliness': for roughness look at plasticization and raw material, for black specks look at carbonization and contamination; drinking water/gas pipes have zero tolerance for black specks, and shutdown management must become an iron rule.
Was this helpful?
0 people found this helpful
Thank you for your feedback!