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 molding.

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