Blown film lines are specialized extrusion systems used to produce thin plastic films through the blown film extrusion process. These films are widely used in packaging, agriculture, and various industrial applications. The process involves extruding molten plastic through a circular die to form a tube, which is then inflated into a bubble, cooled, and flattened to create a continuous film. Here’s an in-depth look at blown film lines:
Components of Blown Film Lines
Extruder
Hopper: Feeds raw material (usually in pellet or powder form) into the extruder.
Barrel and Screw: The screw rotates within the barrel to convey, melt, and mix the material.
Heaters: Surround the barrel to maintain the necessary temperature for melting the material.
2 . Circular Die :
– Shapes molten plastic into continuous tube (parison); critical component determining final product shape dimensions
3 . Air Ring :
– Provides controlled airflow cooling stabilizing inflated bubble ensuring uniform thickness consistency throughout film
4 . Bubble Formation Tower :
– Vertical structure supporting guiding inflated bubble upward allowing sufficient cooling solidification before collapsing flattening
5 . Collapsing Frame :
– Guides collapses bubble into flat double-layered film preparing further processing steps such printing slitting etc .
6 . Nip Rollers :
– Pulls flattened film maintaining consistent tension speed ensuring uniformity throughout length
7 . Winder :
– Collects finished film winding onto rolls facilitating easy handling storage transportation downstream processes applications
Blown Film Extrusion Process
Material Feeding
Raw plastic material (e.g., polyethylene) is fed into the hopper.
Melting and Mixing
The screw conveys the material through the heated barrel where it melts and mixes uniformly.
Extrusion Through Die
Molten plastic is forced through a circular die forming continuous tube (parison).
4 . Inflation Cooling :
– Air introduced center die inflates parison creating bubble; air ring provides controlled cooling stabilizing bubble shape thickness
5 . Bubble Formation Tower :
– Inflated bubble rises vertically tower allowing sufficient cooling solidification before collapsing flattening
6 . Collapsing Flattening :
– Bubble guided collapsed using collapsing frame nip rollers forming flat double-layered film ready further processing steps such printing slitting etc .
7 . Winding Storage :
– Finished film wound onto rolls collected winder facilitating easy handling storage transportation downstream processes applications
Applications of Blown Film Lines
Packaging Industry
Bags: Grocery bags, trash bags, produce bags.
Wraps: Stretch wrap, shrink wrap.
Linings: Liners for boxes or containers.
Agricultural Films
Used for greenhouse covers mulch films silage bags improving crop yield protecting plants from environmental factors pests etc .
3 Industrial Films:
Protective films various industrial applications including construction materials protective coverings etc .
4 Consumer Goods Packaging:
Food packaging wraps pouches personal care products hygiene items packaging solutions requiring flexibility durability barrier properties etc .
Advantages of Blown Film Lines
1.Versatility:
Capable producing wide range films varying thicknesses widths properties meeting diverse industry needs
2.Cost-Effective:
Efficient use raw materials energy resulting lower production costs compared alternative
blown film lines manufacturing methods certain applications
3.High Output Rates:
Capable achieving high output rates making suitable large-scale industrial production environments demanding fast turnaround times high volumes finished products
4.Uniform Thickness Consistency:
Controlled inflation cooling processes ensure uniform thickness consistency throughout entire length produced films enhancing quality reliability end-use applications
By understanding these aspects highlights importance role Blown Film Extrusion Lines play modern Packaging Agricultural Industrial Sectors catering wide range needs efficiently effectively!