Film blowing process of PE heat shrinkable film

There are three main film blowing processes for PE heat shrinkable film: flat blowing, upward blowing and downward blowing. Now PE heat shrinkable film manufacturers will introduce them separately: 1. Flat blowing is a flat extrusion method, which uses a flat head concentric with the extruder screw to place the bubble tube and the center line of the head on the same horizontal plane. This method is only suitable for blowing small diameter PVC film products, and can also be used to produce heat-shrinkable films. 2. Up blowing is a flat extrusion up blowing method: use a right-angle head to pull the extruded pipe ring upwards, and then clamp it with a herringbone after reaching a certain distance. The compressed air introduced at the bottom will expand the extrusion pipe to form For the bubble tube, the amount of compressed air is used to control the horizontal size, and the traction speed is used to control the vertical size. After the bubble tube is cooled and shaped, a blown film is obtained. The plastics that use this method are PVC, PE, PS and HDPE. Therefore, the processing method selected for PE heat shrinkable film is the flat extrusion top blowing method of the blown film forming process. 3. The downward blowing method is a flat extrusion downward blowing method, which uses a right-angle head to make the bubble tube exit from the bottom of the head. This method is suitable for PP, PA and other plastic films with low raw material viscosity and high transparency requirements. Next: The performance of PE heat shrinkable filmPrevious: How to realize the antistatic of PE heat shrinkable film