Blown Film Extrusion Screw Barrel Blown films extrusion is one of many polymer manufacturing processes. This method is used to produce commodity and specialized polymer films that are typically used in packaging such as shrink, stretch, barrier films (used to protect deli meat), frozen food packaging, and shopping bags.
There are many types of polymers that can be used in blown film extrusion with the most common being polypropylene and polyethylene (LDPE, HDPE and LLDPE). This method can manufacture monolayer films as well as more complex multi-layer films that involve co-extrusion to combine more than one plastic into a single film.
There are several advantages of manufacturing film using the blown film extrusion process including the ability to manipulate the mechanical properties of the final plastic based on the process conditions and base polymer(s) used. For example, blown film extrusion inflates the polymer radially while at the same time drawing the polymer upward with rollers. These forces stretch the polymer in both the transverse and draw directions, providing strength in the film. The extent of inflating and drawing can be adjusted to achieve the desired strength in the transverse and draw directions of the final product. Blown film extrusion is also versatile and able to manufacture a variety of single or multi-layer films with a range of film thickness and width.
Parameters
Material:High quality 38CrMoAlA Process:Advanced nitriding & bimetallic process Hardness After Hardening & Tempering:HB280-320 Nitrided Hardness:HV900-1000 Nitrided Case Depth:0.45-0.8mm Nitrided Brittleness:Less than Grade 2 Surface Roughness:Ra 0.4 Screw Straightness:0.015mm Alloy Hardness:HRC 50-65 Alloy Depth:0.8-2.0mm