Manufacturing

From Resin to Film. Every Step Matters.

A cast stretch film machine is an extrusion casting line for PE stretch film. It continuously processes linear low-density polyethylene (LLDPE) with cling masterbatch and other additives into stretch film.

How It Works

Resin pellets are automatically fed into the extruder, where heated screws melt and plasticize the material. A T-die forms the melt into a sheet, which is rapidly cooled on a chilled steel roller. Online thickness measurement, haul-off, tension control and edge-trim recovery precede winding into jumbo rolls for subsequent slitting.

Main Production-Line Components

1. Feeding and blending system: resin mixing and automatic material loading.
2. Extruder system: single-screw extrusion or coextrusion with multiple extruders.
3. T-die: forms the melt into a continuous sheet.
4. Chill-roll assembly: controls film cooling and influences thickness uniformity.
5. Online thickness measurement, haul-off and edge-trim recovery.
6. Winding system: forms the finished rolls and handles roll changes.

Cast Film Process Characteristics

Cast film processing supports uniform thickness and good transparency in continuous production. Three-layer or five-layer coextrusion combines formulations to achieve the required film properties and cling characteristics.

Compared with blown film processing, cast film lines generally require a larger equipment investment and more floor space. Equipment and process settings depend on the production objectives.