What is tpu blown film forming?

TPU blown film molding refers to the blown film process;

It is divided into three types: flat blowing, up blowing and down blowing.

Flat squeeze and blow? Adopt a right-angle die, that is, that discharging direction of the die is vertical to the extrude, the extruded bubble tube is pulled for a certain distance, and then folded by a herringbone plate, and the extrude tube is blown into a bubble tube by compressed air sucked from the bottom, and the transverse expansion size is controlled by the compressed air quantity, and the longitudinal stretching size is controlled by the stretching speed, and the bubble tube can be cooled and shaped to obtain an annular blown film;

Flat extrusion blowing method? Using a right-angle mold, contrary to the upward blowing method, the bubble tube is led out from below the mold and inflated for molding. This method is especially suitable for resin raw materials with low viscosity and plastic films with high transparency requirements.

Flat extrusion and flat blowing? A straight die coaxial with the extruder screw is used, and the bubble tube is on the same horizontal plane with the center line of the die. This method is only suitable for blowing small-caliber films, such as LDPE, PVC and PS films, and the flat blowing method is also suitable for blowing heat-shrinkable films.