Causes and Countermeasures of Transparent Plastic Injection Molding Malfunctions

1、 Bubbles and voids
1. The temperature of the molten material is too high. The molding temperature should be appropriately reduced.
2. The injection pressure is too low. Should be appropriately improved.
3. The boost time is too short. It should be extended appropriately.
4. The holding time is too short. It should be extended appropriately.
5. The mold temperature is too low. Should be appropriately improved.
6. Poor drying of raw materials. Pre drying treatment should be carried out, and the drying temperature should be increased and the drying time should be extended.
7. There is a blockage in the flow channel. It should be thoroughly removed.
2、 Pores and sand holes
1. Foreign objects and impurities are mixed in the raw material. Thorough cleaning should be carried out.
2. The injection pressure is too low. Should be appropriately improved.
3. Insufficient screw back pressure. Should be appropriately increased.
4. The screw speed is too high. It should be appropriately reduced.
5. Poor exhaust of the mold. Mold exhaust should be increased.
6. The cooling time of the product in the mold is too short. It should be extended appropriately.
3、 Welding marks and material flow marks
1. The melt temperature is too low. The molding temperature should be appropriately increased.
2. The injection pressure is too low. Should be appropriately improved.
3. Insufficient supply of materials. Should increase the supply volume or switch to a larger specification injection machine.
4. The mold temperature is too low. Should be appropriately improved.
5. The holding time is too short. It should be extended appropriately.
6. The boost time is too short. It should be extended appropriately.
7. There are obstructions in the gate and runner. It should be thoroughly removed.
8. Poor exhaust of the mold. The mold exhaust hole should be increased or the clamping force should be reduced to exhaust at the clamping or fusion point.
9. The pouring system structure is unreasonable. The flow channel form should be improved, and the gate should be repositioned and opened.
4、 Cracks and streaks
1. The temperature of the molten material is too high. The forming temperature should be properly reduced and the temperature distribution of the barrel should be adjusted.
2. The injection pressure is low. Should be appropriately improved.
3. Foreign objects and impurities are mixed in the raw material. It should be cleared.
4. Poor drying of raw materials. The drying temperature should be increased and the drying time should be extended.
5. The forming cycle is too long. It should be appropriately shortened.
6. The screw back pressure is too high or too low. Appropriate adjustments should be made.
7. The design of the pouring system is unreasonable. The gate, runner, and gate should be checked for blockages, and the layout and cross-sectional size of the gate and runner should be adjusted reasonably.
5、 Swirling pattern
1. The melt temperature is too high or too low. Appropriate adjustments should be made.
2. There is too much supply. It should be appropriately reduced.
3. The mold temperature is too low. Should be appropriately improved.
4. The nozzle hole is blocked. It should be thoroughly removed.
5. Improper gate positioning. The opening should be re selected.
6. There are obstructions in the gate and runner. It should be thoroughly removed.
6、 Black spots and stripes
1. Impurities are mixed in the raw material. Thorough cleaning should be carried out.
2. The temperature of the material barrel is too high or too low. Appropriate adjustments should be made.
3. The temperature distribution in each section of the barrel is unreasonable. Appropriate adjustments should be made.
4. Injection pressure too high or too low. Appropriate adjustments should be made.
5. The structural size of the pouring system is too small, the positioning is improper, and the flow resistance is too high. The cross-section of the gate and runner should be appropriately enlarged to check for any obstructions in the runner.
6. Poor exhaust of the mold. Mold exhaust should be increased to improve mold exhaust performance.
7. There are excessive hot spots and stagnant corners in the material barrel and nozzle. The corners of the stagnant material should be repaired to eliminate hot spots.
7、 Cloud patterns and fog halos
1. The melt temperature is too low. The molding temperature should be appropriately increased.
2. The mold temperature is too low. Should be appropriately improved.
3. The injection pressure is too low. Should be appropriately improved.
4. The screw back pressure is too low. Should be appropriately improved.
5. Impurities are mixed in the raw material. Thoroughly remove or replace with new materials.
6. The temperature distribution in each section of the barrel is unreasonable. Appropriate adjustments should be made.
7. The moisture or volatile matter content in the raw material is too high. Pre drying treatment should be carried out.
8、 Poor gloss and rough surface
1. The melt temperature is too low. The molding temperature should be appropriately increased.
2. The injection pressure is too low. Should be appropriately improved.
3. The mold temperature is low. Should be appropriately improved.
4. Insufficient supply of materials. The supply volume should be increased.
5. Improper gate positioning. The opening should be re selected.
6. Insufficient cooling time. It should be extended appropriately.
7. There is a blockage in the flow channel. It should be thoroughly removed.
8. The surface finish of the mold cavity is too poor. Grinding and polishing should be carried out to improve surface smoothness.
9、 Depression
1. The temperature of the molten material is too high. The molding temperature should be appropriately reduced.
2. The injection pressure is too low. Should be appropriately improved.
3. The mold temperature is too high. It should be appropriately reduced.
4. Insufficient supply of materials. The supply volume should be increased.
5. The boost time is too short. It should be extended appropriately.
6. Insufficient cooling time. It should be extended appropriately.
7. The holding time is too short. It should be extended appropriately.
8. Poor exhaust of the mold. Mold exhaust should be increased.
9. There is a blockage in the flow channel. It should be thoroughly removed.
10、 Peeling and layering
1. Insufficient supply of materials. Should increase the supply volume or switch to a larger specification injection machine
2. The mold temperature is too low. Should be appropriately improved.
3. Foreign objects and impurities are mixed in the raw material. Thoroughly remove or replace with new materials.
Bubbles and voids
1. The temperature of the molten material is too high. The molding temperature should be appropriately reduced.
2. The injection pressure is too low. Should be appropriately improved.
3. The boost time is too short. It should be extended appropriately.
4. The holding time is too short. It should be extended appropriately.
5. The mold temperature is too low. Should be appropriately improved.
6. Poor drying of raw materials. Pre drying treatment should be carried out, and the drying temperature should be increased and the drying time should be extended.
7. There is a blockage in the flow channel. It should be thoroughly removed.
Pores and sand holes
1. Foreign objects and impurities are mixed in the raw material. Thorough cleaning should be carried out.
2. The injection pressure is too low. Should be appropriately improved.
3. Insufficient screw back pressure. Should be appropriately increased.
4. The screw speed is too high. It should be appropriately reduced.
5. Poor exhaust of the mold. Mold exhaust should be increased.
6. The cooling time of the product in the mold is too short. It should be extended appropriately.
Welding marks and material flow marks
1. The melt temperature is too low. The molding temperature should be appropriately increased.
2. The injection pressure is too low. Should be appropriately improved.
3. Insufficient supply of materials. Should increase the supply volume or switch to a larger specification injection machine.
4. The mold temperature is too low. Should be appropriately improved.
5. The holding time is too short. It should be extended appropriately.
6. The boost time is too short. It should be extended appropriately.
7. There are obstructions in the gate and runner. It should be thoroughly removed.
8. Poor exhaust of the mold. The mold exhaust hole should be increased or the clamping force should be reduced to exhaust at the clamping or fusion point.
9. The pouring system structure is unreasonable. The flow channel form should be improved, and the gate should be repositioned and opened.
Cracks and streaks
1. The temperature of the molten material is too high. The forming temperature should be properly reduced and the temperature distribution of the barrel should be adjusted.
2. The injection pressure is low. Should be appropriately improved.
3. Foreign objects and impurities are mixed in the raw material. It should be cleared.
4. Poor drying of raw materials. The drying temperature should be increased and the drying time should be extended.
5. The forming cycle is too long. It should be appropriately shortened.
6. The screw back pressure is too high or too low. Appropriate adjustments should be made.
7. The design of the pouring system is unreasonable. The gate, runner, and gate should be checked for blockages, and the layout and cross-sectional size of the gate and runner should be adjusted reasonably.
Swirling pattern
1. The melt temperature is too high or too low. Appropriate adjustments should be made.
2. There is too much supply. It should be appropriately reduced.
3. The mold temperature is too low. Should be appropriately improved.
4. The nozzle hole is blocked. It should be thoroughly removed.
5. Improper gate positioning. The opening should be re selected.
6. There are obstructions in the gate and runner. It should be thoroughly removed.
Black spots and stripes
1. Impurities are mixed in the raw material. Thorough cleaning should be carried out.
2. The temperature of the material barrel is too high or too low. Appropriate adjustments should be made.
3. The temperature distribution in each section of the barrel is unreasonable. Appropriate adjustments should be made.
4. Injection pressure too high or too low. Appropriate adjustments should be made.
5. The structural size of the pouring system is too small, the positioning is improper, and the flow resistance is too high. The cross-section of the gate and runner should be appropriately enlarged to check for any obstructions in the runner.
6. Poor exhaust of the mold. Mold exhaust should be increased to improve mold exhaust performance.
7. There are excessive hot spots and stagnant corners in the material barrel and nozzle. The corners of the stagnant material should be repaired to eliminate hot spots.
Cloud patterns and fog halos
1. The melt temperature is too low. The molding temperature should be appropriately increased.
2. The mold temperature is too low. Should be appropriately improved.
3. The injection pressure is too low. Should be appropriately improved.
4. The screw back pressure is too low. Should be appropriately improved.
5. Impurities are mixed in the raw material. Thoroughly remove or replace with new materials.
6. The temperature distribution in each section of the barrel is unreasonable. Appropriate adjustments should be made.
7. The moisture or volatile matter content in the raw material is too high. Pre drying treatment should be carried out.
Poor gloss and rough surface
1. The melt temperature is too low. The molding temperature should be appropriately increased.
2. The injection pressure is too low. Should be appropriately improved.
3. The mold temperature is low. Should be appropriately improved.
4. Insufficient supply of materials. The supply volume should be increased.
5. Improper gate positioning. The opening should be re selected.
6. Insufficient cooling time. It should be extended appropriately.
7. There is a blockage in the flow channel. It should be thoroughly removed.
8. The surface finish of the mold cavity is too poor. Grinding and polishing should be carried out to improve surface smoothness.
sunken
1. The temperature of the molten material is too high. The molding temperature should be appropriately reduced.
2. The injection pressure is too low. Should be appropriately improved.
3. The mold temperature is too high. It should be appropriately reduced.
4. Insufficient supply of materials. The supply volume should be increased.
5. The boost time is too short. It should be extended appropriately.
6. Insufficient cooling time. It should be extended appropriately.
7. The holding time is too short. It should be extended appropriately.
8. Poor exhaust of the mold. Mold exhaust should be increased.
9. There is a blockage in the flow channel. It should be thoroughly removed.
Peeling and layering
1. Insufficient supply of materials. Should increase the supply volume or switch to a larger specification injection machine
2. The mold temperature is too low. Should be appropriately improved.
3. Foreign objects and impurities are mixed in the raw material. Thoroughly remove or replace with new materials.
Bubbles and voids
1. The temperature of the molten material is too high. The molding temperature should be appropriately reduced.
2. The injection pressure is too low. Should be appropriately improved.
3. The boost time is too short. It should be extended appropriately.
4. The holding time is too short. It should be extended appropriately.
5. The mold temperature is too low. Should be appropriately improved.
6. Poor drying of raw materials. Pre drying treatment should be carried out, and the drying temperature should be increased and the drying time should be extended.
7. There is a blockage in the flow channel. It should be thoroughly removed.
Pores and sand holes
1. Foreign objects and impurities are mixed in the raw material. Thorough cleaning should be carried out.
2. The injection pressure is too low. Should be appropriately improved.
3. Insufficient screw back pressure. Should be appropriately increased.
4. The screw speed is too high. It should be appropriately reduced.
5. Poor exhaust of the mold. Mold exhaust should be increased.
6. The cooling time of the product in the mold is too short. It should be extended appropriately.
Welding marks and material flow marks
1. The melt temperature is too low. The molding temperature should be appropriately increased.
2. The injection pressure is too low. Should be appropriately improved.
3. Insufficient supply of materials. Should increase the supply volume or switch to a larger specification injection machine.
4. The mold temperature is too low. Should be appropriately improved.
5. The holding time is too short. It should be extended appropriately.
6. The boost time is too short. It should be extended appropriately.
7. There are obstructions in the gate and runner. It should be thoroughly removed.
8. Poor exhaust of the mold. The mold exhaust hole should be increased or the clamping force should be reduced to exhaust at the clamping or fusion point.
9. The pouring system structure is unreasonable. The flow channel form should be improved, and the gate should be repositioned and opened.
Cracks and streaks
1. The temperature of the molten material is too high. The forming temperature should be properly reduced and the temperature distribution of the barrel should be adjusted.
2. The injection pressure is low. Should be appropriately improved.
3. Foreign objects and impurities are mixed in the raw material. It should be cleared.
4. Poor drying of raw materials. The drying temperature should be increased and the drying time should be extended.
5. The forming cycle is too long. It should be appropriately shortened.
6. The screw back pressure is too high or too low. Appropriate adjustments should be made.
7. The design of the pouring system is unreasonable. The gate, runner, and gate should be checked for blockages, and the layout and cross-sectional size of the gate and runner should be adjusted reasonably.
Swirling pattern
1. The melt temperature is too high or too low. Appropriate adjustments should be made.
2. There is too much supply. It should be appropriately reduced.
3. The mold temperature is too low. Should be appropriately improved.
4. The nozzle hole is blocked. It should be thoroughly removed.
5. Improper gate positioning. The opening should be re selected.
6. There are obstructions in the gate and runner. It should be thoroughly removed.
Black spots and stripes
1. Impurities are mixed in the raw material. Thorough cleaning should be carried out.
2. The temperature of the material barrel is too high or too low. Appropriate adjustments should be made.
3. The temperature distribution in each section of the barrel is unreasonable. Appropriate adjustments should be made.
4. Injection pressure too high or too low. Appropriate adjustments should be made.
5. The structural size of the pouring system is too small, the positioning is improper, and the flow resistance is too high. The cross-section of the gate and runner should be appropriately enlarged to check for any obstructions in the runner.
6. Poor exhaust of the mold. Mold exhaust should be increased to improve mold exhaust performance.
7. There are excessive hot spots and stagnant corners in the material barrel and nozzle. The corners of the stagnant material should be repaired to eliminate hot spots.
Cloud patterns and fog halos
1. The melt temperature is too low. The molding temperature should be appropriately increased.
2. The mold temperature is too low. Should be appropriately improved.
3. The injection pressure is too low. Should be appropriately improved.
4. The back pressure of the screw is too low. Should be appropriately improved.
5. Impurities are mixed in the raw material. Thoroughly remove or replace with new materials.
6. The temperature distribution in each section of the barrel is unreasonable. Appropriate adjustments should be made.
7. The moisture or volatile matter content in the raw material is too high. Pre drying treatment should be carried out.
Poor gloss and rough surface
1. The melt temperature is too low. The molding temperature should be appropriately increased.
2. The injection pressure is too low. Should be appropriately improved.
3. The mold temperature is low. Should be appropriately improved.
4. Insufficient supply of materials. The supply volume should be increased.
5. Improper gate positioning. The opening should be re selected.
6. Insufficient cooling time. It should be extended appropriately.
7. There is a blockage in the flow channel. It should be thoroughly removed.
8. The surface finish of the mold cavity is too poor. Grinding and polishing should be carried out to improve surface smoothness.
sunken
1. The temperature of the molten material is too high. The molding temperature should be appropriately reduced.
2. The injection pressure is too low. Should be appropriately improved.
3. The mold temperature is too high. It should be appropriately reduced.
4. Insufficient supply of materials. The supply volume should be increased.
5. The boost time is too short. It should be extended appropriately.
6. Insufficient cooling time. It should be extended appropriately.
7. The holding time is too short. It should be extended appropriately.
8. Poor exhaust of the mold. Mold exhaust should be increased.
9. There is a blockage in the flow channel. It should be thoroughly removed.
Peeling and layering
1. Insufficient supply of materials. Should increase the supply volume or switch to a larger specification injection machine
2. The mold temperature is too low. Should be appropriately improved.
3. Foreign objects and impurities are mixed in the raw material. Thoroughly remove or replace with new materials.