TECHNOLOGY

Non-uniform film speed
Cause(s) Possible Solution(s)
Unstable Die Head temperature
  • Check the Heater function is normal
  • Check the Thermocouple position is correct
Die Head Throughput fluctuations
  • Adjust the Die Gap
  • Regular cleaning of Die Head, Screw and Filter
Non-uniform cooling air volume
  • Check Air Ring for dirt buildup or breakage
  • Adjust Air Ring position
  • Check whether Air Pipe is damaged
The air flow in the factory is too fast
  • Do not let outdoor air directly enter the factory
Extruder Throughput instability
  • Cool down the hopper throat to avoid plastic blocking
  • Replace the strainer meshes of Filter to avoid blocking
  • Matter of the formula
Insufficient film strength
Cause(s) Possible Solution(s)
Blow-Up Ratio
  • Use a smaller Die Head to increase the Blow-Up Ratio
Improper Die design or scratches
  • Clear Die impurities
  • Fix scratches on the Die Head
  • Avoid seams by design
Material cracking
  • Change the material
  • Turn downffeating temperature
Inappropriate raw material formula
  • Select raw materials with suitable Melt Index (MI)
  • Select compatible Additives
Uneven gels mix
  • Use screw with a greater L/D
  • Adjust the melt temperature
  • Use multi-layer strainer meshes for Filter, or reduce the Die Gap, to improve back pressure
Insufficient film openness
Cause(s) Possible Solution(s)
Improper film roll storage
  • Avoid piling up
  • Store in a well-ventilated place
Winding tension is too high
  • Adjust the winding tension
Nip Roller pressure is too high
  • Reduce Nip Roller pressure
Tubular film temperature is too high
  • Increase cooling air volume of Air Ring
  • Use cold air cooling
  • Reduce Die Head temperature
  • Equip Take-Up Roller with waterway
Unsuitable material formula
  • Add anti-phase adhesive or slippery agent
Film scratching or wrinkling
Cause(s) Possible Solution(s)
Tubular film asymmetry or swing
  • Adjust the air flow of Air Ring
  • Avoid too fast air flow inside the factory
  • Use a hash-shape frame to steady the film
Inappropriate Nip Roller
  • Align Nip Roller and keep it horizontally
  • Avoid Nip Roller damages
Improper Collapsing Frame
  • Adjust Collapsing Frame angle
  • Adjust Collapsing Frame length
  • Reduce friction to Collapsing Frame
Uneven winding tension
  • Adjust the winding angle
Die Head scratches
  • Refinishing Die scratches
Film with fish-eye,arrows lines and coking spots
Cause(s) Possible Solution(s)
Improper Operating in material exchange
  • Avoid overheating of the gels
  • The new material should have a lower MI than the old material
  • Clean the machine before exchanging the material
Melt temperature is too high or too low
  • Adjust the melt temperature
  • Check the heater function
Raw materials contain impurities
  • Avoid dirt entering feed hopper
  • Avoid using recycled materials
Uneven gels mix
  • Increase back pressure
  • Use screw with a greater L/D
  • Avoid existence of dead corner at Extruder or Die Head
Tubular film rupture
Cause(s) Possible Solution(s)
Melt temperature is too high or too low
  • Adjust the melt temperature
Improper use of additives
  • Reduce color masterbatch
  • Reduce waste recycling rate
Insufficient melt mix
  • Add more strainer meshes of Filter or reduce the Die Gap to increase back pressure
  • Use screw with a greater L/D
Non-smooth material feeding
  • Clean Die Head and Screw & Barrel
  • Replace the strainer meshes of Filter to avoid blockage
  • Cool down the hopper
  • Remove raw materials impurities
Cooling line too low
  • Raise the cooling line
Poor film printability
Cause(s) Possible Solution(s)
Inappropriate ink
  • Choose the right ink
Improper use of additives
  • Reduce the amount of additives
  • Use the appropriate surface lubricant
Insufficient corona treatment
  • Increase the treatment voltage or wattage
  • Reduce the Take-Up speed
  • Narrow the gap of the electrode
  • Raise the electrode treatment temperature
Air humidity too high
  • Reduce the air humidity