Plastic Injection molding is the principal method of forming thermoplastic materials. Modifications of the plastic injection molding process are sometimes used for thermosetting plastics.
In Plastic injection molding, plastic material is put into a hopper which feeds into a heated injection unit. A reciprocating screw pushes the plastic through this long heating chamber, where the material is softened to a fluid state. At the end of this chamber there is a nozzle which abuts firmly against an opening into a cool, closed mold. The fluid plastic is forced at high pressure through this nozzle into the cold plastic mold. A system of clamps hold the mold halves shut. As soon as the plastic cools […]