Black spots/impurities：
1.Raw Material Management: Strengthen incoming material inspection, clean recycled crushed materials; maintain a clean production environment.
2.Equipment Cleaning: Regularly and thoroughly clean the screw, machine head, die, filter screen, exhaust port and other components.
3.Process Control: Avoid excessive temperature; optimize screw configuration to prevent local overheating and shearing.
strand breakage：
1.Optimize Plasticization: Adjust the temperature and screw speed to ensure uniform plasticization.
2.Ensure Venting Efficiency: Fully dry the materials; inspect and clean the vacuum system to ensure it is unobstructed.
3.Match Formulation with Process: Pay attention to the compatibility of blends; adjust the process according to the material viscosity.
4.Adjust Cooling Parameters: For materials prone to strand breakage, appropriately increase the cooling water temperature and reduce the water flow rate.
Agglomerated pellets / Long strands
1.Maintain the Pelletizing System: Keep the cutter blades sharp; adjust the cutter gap and rotating speed to appropriate levels.
2.Enhance Cooling Performance: Ensure the cooling water temperature and flow rate are sufficient to fully quench the surface of the strands.
3.Stabilize Traction: Adjust the strand guide wheels to ensure the strands enter the pelletizer in a straight and stable manner.
Hollow pellets
1.Ensure Venting Efficiency: Ensure the vacuum system operates effectively and the raw materials are fully dried.
2.Improve Plasticization: Appropriately increase the processing temperature to ensure complete melting.
3.Control Cooling Process: For crystalline materials, avoid using cooling water with excessively low temperature.
Hopper bridging
1.Optimize the Hopper: Adopt a reasonable cone angle (e.g., less than 45 degrees), or install a vibrator and agitator.
2.Pretreat the Materials: Add a small amount of lubricant such as white oil to reduce friction and prevent caking.
3.Control the Temperature of the Feeding Zone: Prevent the materials from softening in the feeding section.
Excessive fine powder
Optimize the pelletizing process: Adjust the temperature of strands during pelletizing (e.g., close to the material's softening point) and keep the cutter blades sharp.
Color unevenness/color spots
1.Ensure Uniform Mixing: Optimize the mixing process and duration.
2.Stabilize the Production Process: Strictly control the processing temperature to prevent overheating.
3.Thoroughly Clean the Equipment: Strictly clean the barrel and screw when changing materials or colors.