Blown Film A process known as blow film extrusion uses an industrial blower to expand a hot plastic tube into a light, strong plastic bag. The air inflates the plastic tube like a balloon until a bag with the desired shape, size, and wall thickness is formed.

The process results in a thin, tubular film that can be used in numerous applications, ranging from plastic bags to packaging films. The basic components essential to this process include the extruder, die, air ring, bubble cooling, collapsing frame, and take-up unit.

Plastic melt is extruded through an annular slit die, vertically to form thin walled tube Air is introduced in the centre of the die to blow up the tube like a balloon (IBC) Air ring blows onto the hot film to cool it (outside and inside the tube) The tube passes through nip rolls where is flattened Collapsed tube is taken back down the extrusion tower via more idler rollers On winder the tube or film is wound into rolls