Sheet Extrusion Lines

The sheet extrusion is a common process to extrude plastic sheets or films that are too thick to be blown. In Particular, plastic granules including additives, are fed from the extruder hopper along a heated cylinder by a rotating screw, melted & homogenized and conveyed to the sheet die.

There are two types of dies used: T-shaped and coat hanger. The purpose of these dies is to reorient and guide the flow of polymer melt from a single round output from the extruder to a thin, flat planar flow.

Depending on the application, there are a number of variations including the number and rotation of the screws, the screw and cylinder geometry and the structure. The die itself can be fed by several extruders extruding different thermoplastics, resulting in layered or concentric co-extrudates. The extrudate is then cooled via chill rolls and transported to slitting and winding stations.