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.

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.

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.

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.