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Extrusion molding

Extrusion molding.

  • Extrusion is a method by which molten plastic is pushed through a two dimensional opening.
  • Example of extrusion can be seen when toothpaste is squeeze out of a tube.
  • Thermoplastics such as PVC,LDPE, HDPE,PP can all be extruded.
  • In this method the polymer in form of pellets are fed into the extruder through a Hopper.
  • Then the material are pushed forward by a feeding screw which is then passed out through the orifice giving continuous polymer product.
  • The heaters present over the extruder make the polymer soft and melts it.
  • Here cross-linking occur during heating and melting of polymer material.
  • This process continuous as long as raw pellets are supplied.
  • This method is used to produce long shape polymers with constant cross-section.
  • Extruding are usually used for frames like window profile.
  • It is also used to make pipes, drinking straws and rods etc.Check out injection molding also
    Extrusion moulding
    Extrusion molding.

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