Problems and Solutions

Blackheads
In the Machine:
- The weight may be very high.
- It may have been closed for a long time.
- The hive may not have been cleaned properly.
- The correct nozzle may not have been used.
In the Mold:
- Runner with angular corners
In the Raw Material:
- It may contain mixed other materials.
- The other material inside may burn.
Solutions in Order:
- The machine should be cleaned with the correct material at the same temperature.
- It should be checked whether another material has mixed in.
- The runner entries and type should be checked.
- The filter perforation should be checked.
Air and Gas Bubbles
In the Machine:
- The injection pressure may be very low.
- The backflow valve may be faulty.
- The back pressure may be too long.
- The melting process may be too fast.
- Air may be trapped at the funnel inlet.
- Poor feeding may occur.
In the Mold:
- The mold temperature may be low.
- The mold gas outlet may be closed.
- The runner entry thickness of the part.
- It may go from thin to thick.
In the Raw Material:
- The material may not be able to withstand high temperatures.
Solutions in Order:
- The injection pressure and extrusion pressure should be increased.
- The back pressure should be increased.
- The mold temperature should be increased.
- The backflow valve should be checked.
- The mold air channel should be checked.
- The runner diameter should be increased.
Flow Marks
In the Machine:
- The injection speed may be too low or too high.
- The injection pressure may be too low.
- The extrusion pressure may be too low.
In the Mold:
- The mold temperature control is not good.
- The mold temperature at the runner entry may be too high.
- The mold may be too cold.
- The runner diameter may be too small.
- Incorrect runner entry.
- Incorrect hot runner system.
In the Raw Material:
- The material temperature may be low.
Solutions in Order:
- The injection speed should be adjusted.
- The possibility of unmelted material should be checked.
- The injection cavity should be checked.
Surface Burns (Diesel Effect)
In the Machine:
- The backflow valve may be faulty.
- The injection speed may be too fast or too high.
- The back pressure may be too high.
In the Mold:
- The air outlet may be closed.
- Burning due to sharp corners in the mold.
- The runner entry may be narrow.
In the Raw Material:
- The material may burn due to high temperature or may burn by friction due to low temperature.
Solutions in Order:
- The air intake channels should be checked for blockages.
- The injection speed should be reduced.
- The injection pressure should be reduced.
- Gradual injection should be tried.
- The heaters should be checked to ensure they are working properly.
- The screw speed should be reduced.
- The nozzle temperature should be reduced.
Part Peeling
In the Machine:
- The injection speed may be too high.
In the Mold:
- The mold may be too cold.
- There may be sharp corners in the runner.
- High heat formation due to sharp corners.
In the Raw Material:
- The material melt temperature may be too high.
- The material may not be fully melted.
- Another polymer may have been added.
- There may be excessive scrap or mixed broken material.
Solutions in Order:
- The melt temperature should be increased.
- The mold temperature should be increased.
- The injection speed should be reduced.
- The masterbatch should be changed.
- The amount of scrap or broken material should be reduced.
- The material or drying should be checked.
- The sharp corners should be given a radius.
Size Variation
In the Machine:
- The injection pressure may be too low.
- The extrusion time may be too short.
- The cycle time may be too short.
- The heaters may be faulty.
- The backflow valve may be faulty.
In the Mold:
- The mold temperature may be too high.
- The runner entries may be too small.
- The mold may be too small.
In the Raw Material:
- The wrong material may have been chosen.
Solutions in Order:
- The melt temperature should be increased.
- The mold temperature should be increased.
- The injection speed should be reduced.
- The cycle time should be improved.
- The runner diameter should be increased.
- For glass-fiber reinforced materials, the runner entry should be changed.
Burr
In the Machine:
- The clamping pressure may be too low.
- The injection pressure may be too high.
- The injection speed may be too high.
In the Mold:
- The mold may be improperly connected.
- There may be wear or damage on the mold surfaces.
- The mold surface may be too large.
In the Raw Material:
- The material temperature may be too high.
- The material fluidity may be too high.
Solutions in Order:
- The injection speed should be reduced.
- The injection pressure should be reduced.
- The clamping force should be increased.
- The melt temperature should be reduced.
- The mold temperature should be reduced.
- The clamping force should be increased.
Flow Marks on the Part Surface
In the Machine:
- The injection speed may be too high.
In the Mold:
- The mold may be too cold.
- The runner diameters may be too low.
- Incorrect runner entry.
In the Raw Material:
- The material may be melted.
Solutions in Order:
- The injection pressure should be increased.
- The nozzle heater should be checked.
- The mold temperature should be increased.
- The melt temperature should be increased.
- The runner diameter should be increased.
- The runner entry should be changed or a direct entry should be used.
Round Rings on the Part Surface
In the Machine:
- The injection speed may be too low.
- The injection pressure may be too low.
In the Mold:
- The mold temperature may be too low.
- There may be a different pattern on the mold surface.
In the Raw Material:
- The material melt temperature may be too low.
Solutions in Order:
- The injection speed should be increased.
- The injection pressure should be increased.
- The melt temperature should be increased.
- The mold temperature should be increased.
- The mold pattern should be checked.
Adhesion to the Mold (Female Mold)
In the Machine:
- The injection pressure may be too high.
- The injection speed may be too high.
- The molding time may be too long.
- The material intake may be too high.
In the Mold:
- The mold temperature may be too high.
- The mold may be too cold.
- The mold surface pattern may be poor.
In the Raw Material:
- The nozzle temperature may be too high.
Solutions in Order:
- The cycle time should be checked. (Cooling)
- The injection pressure should be reduced.
- The molding time should be reduced.
- The injection speed should be reduced.
- The material intake should be adjusted for stable cushioning.
- The mold surface should be checked.
- The mold opening time should be increased.
- The material temperature should be reduced.
- The mold temperature should be reduced.
- The correct mold separator should be used.