Plastic Molding

Plastic Molding

Plastic molding compose parts and products manufactured from the plastic injection molding process. Plastic molders fabricate parts with a range of complexities, from simple shapes to close tolerance precision parts. Molded plastic parts are used in the medical equipment, computer and automotive industries to produce office supplies, children's toys, tools, catheters, contact lens containers, monitors, mop buckets, video game cartridges and screwdriver handles. Plastic manufacturers primarily fabricate plastic molding with thermoplastics. However, a small amount of thermosets and elastomers are also subjected to this process. Biodegradable plastics are also used to produce plastic molding. Products such as biodegradable cutlery and plastic pots are now being produced using this molding process.

Injection molding machines produce plastic molding through a simple process. Plastic pellets or granules are fed into a hopper where a screw pushes them to a heated barrel, where they are heated until molten. The melted plastic material is then injected into the cavity of a split die chamber or mold, which is then clamped shut. The plastic resin is left to cool as water or other fluids circulate through the mold, extracting the heat. The molded plastic part is held in the mold under high pressure until the part solidifies. The plastic part is finally ejected from the plastic molding, and the process begins again. Linear low density polyethylene, polypropylene and polystyrene are all thermoplastics that are used in plastic molding.