FAQs
Why are there black spots in the produced plastic granule in the process of plastic recycling?
Why are there black spots in the produced plastic granule in the process of plastic recycling?
| Reasons | Solutions |
| The recycled plastics contain many impurities | Strengthen the cleaning and screening processes, increase mesh numbers or layers of filter screen |
| The feeding bin experiences localized overheating, causing carbonization of the materials. | Reduce the extruding temperature and increase mesh numbers or layers of filter screen |
| The plastic extruder machine features strong local shearing force, resulting in material carbonization. | Reduce the extruding speed and increase mesh numbers or layers of filter screen |
| The pressure of die-head is too high and the reflux material is too great, causing material carbonization. | Increase the temperature of the die-head; Change the filter screen and reduce its mesh numbers. |
| The equipment is aging and the adhesion inner the cylinder increases. | Change equipment or spare parts |
| The accumulated material in the discharge hole is carbonized and discharged. | Clean the gas exhaust hole regularly. |
| Discharge hole is not smooth and the accumulated material is carbonized and discharged. | Clean regularly or change spare parts. |
| The screw thread is damaged and the material in the dead corner is carbonized. | Replace or repair the screw. |
| Gas exhaust is blocked, leading to materials carbonization. | Clean the exhaust hole and keep it clear. |
Why do broken plastic strips occur frequently when the materials are extruded?
Why do broken plastic strips occur frequently when the materials are extruded?
| Reasons | Solutions |
| Insufficient extrusion amount | Raise the rotating speed of screw, feeding speed or change the filter screen. Reduce the number of die outlet holes |
| The high temperature of the die-head leads to low material viscosity. | Properly reduce the temperature of die head. |
| Poor plasticizing causes plastic agglomerates | Increase the extruding temperature or speed to promote full plasticizing. |
| Mixing materials are different in characteristics. | Adjust the temperature or speed based on actual conditions. |
| Gas exhaust is blocked and the plastic strips have pores. | Ensure smooth exhaust and reduce the extruding temperature properly. |
Why are many plastic granules coming out hollow?
Why are many plastic granules coming out hollow?
| Reasons | Solutions |
| High moisture content | Increase the drying temperature or time to ensure clear discharge hole. |
| The processing temperature is low, causing incomplete plasticization of the materials. | Improves the processing temperature reasonably. |
| The water temperature is so low that materials shrinks, resulting in a shrinkage cavity. | Reduces the temperature of die-head and improves the temperature of cooling water reasonably. |
What is the reason of material leaking in the exhaust port of the extruder during the plastic granulating process?
What is the reason of material leaking in the exhaust port of the extruder during the plastic granulating process?
| Reasons | Solutions |
| Feeding speed and the rotary speed of the main extruder are not matching. | Reduces the feeding speed or improves the rotating speed of the main machine properly. |
| The temperature in natural exhaust port is low, resulting in poor plasticizing. Under compression of the extruder, the material will leak. | Improve the temperature in the natural exhaust port to boost plasticizing. |
| The die screen is clogged and material is leaking from the vent port. | Replace the screen promptly. |
| Material moisture is too high and plasticizing is insufficient. | Equip a reverse conveying element or reverse kneading block. |