Injection molding.

Injection molding is a process in which molten polymer is forced under high pressure into the mold cavity through an opening called sprue.
In this process the pelletized material is put into the cylinder through a Hopper, from where charge passes into the heating chamber where it melts and then it passes into the mold cavity through the nozzle where the polymer attains its shape.
The cylinder is provided with a screw which is also called receprocating screw since it not only rotates but also moves forward and backward according to the polymer molding step.
The characteristics of this process is that the time cycle of this process is very small.
This process is highly productive and polymer of accurate shape and size are formed.(Check out Extrusion molding also)
This process is generally used for thermoplastics.
The thermoplastics used in injection molding process are polypropylene (PP), polycarbonate (PC), acrylonitrile butadiene styrene (ABS) and nylon-6 (N6) etc.

Injection molding.

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Polymers

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