What is coextruded flat film?


The word "coextruded" implies that two or more different types of plastic are extruded at the same time. "Flat film" means that the product is a flat sheet that is thinner than approximately 0.004". For example, cling wrap is considered a flat film. However, the following discussion also applies to flat sheet, and the terms film and sheet will be used interchangably.
The screw, when inserted into the barrel, will protrude outside the rear of the barrel enabling the attachment of an electric drive whereby it may be rotated. As the screw is rotated, raw plastic material in the form of particles may be dropped into the barrel by way of a feed hole provided in the side of the barrel. The plastic particles are compressed between the screw and barrel. The induced friction between these two surfaces causes melting of the plastic material.

The amount of plastic that may be melted per unit of time is directly proportional to the horsepower of the extruder drive and the diameter of the extruder barrel.


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