Processing Machinery
8 visualizaciones
Dull surface of linear low density polyethylene extruded products (Variant: strengthened measures)
Fenómeno del problema
The extrudate surface is dull and lusterless, with gloss significantly lower than the standard sample.
Dull surface affects product appearance quality and use in decorative products.
In particular, additional attention is needed on the original basis; this problem is more prominent and requires key attention.
Análisis de la causa
(1) Die temperature too low; melt surface fails to fully replicate the die surface
(2) Cooling rate too fast; melt has no time to form a smooth surface
(3) Insufficient die inner wall finish
(4) Melt temperature too low, poor flowability
(5) Fillers or additives in raw material affect gloss
(6) On the original basis, additional attention is needed as process parameter fluctuations or equipment status changes have aggravated this problem
Solución
(1) Increase die temperature to the higher value within the 190-250°C range
(2) Appropriately reduce cooling rate, increase cooling water temperature
(3) Polish die inner wall to Ra≤0.1μm, chrome plating treatment
(4) Appropriately increase barrel temperature to the higher value within the 190-250°C range
(5) Select raw material grades with good gloss, control filler content
(6) And strengthen process monitoring; on the original basis, additional attention is needed, with special attention to parameter stability
Conclusión clave
Dull surface is caused by low die temperature or too fast cooling; die temperature needs to be increased and cooling slowed.
Targeted preventive measures need to be taken in different production scenarios.
¿Le ha resultado útil?
0 personas encontraron esto útil
¡Gracias por sus comentarios!