270. Plastic mold
Plastic molding is an important method, applicable primarily to thermoplastic. Molding can yield an infinite variety of precision plastic parts.
The plastic melting and cooling process is integral to the use of thermoplastic materials. At room temperature thermoplastic materials (polypropylene, nylon and PET etc) are solid. For such a plastic to be transformed into the desired shape it must first be heated to a molten state. When molten, it can be processed (via extrusion, injection molding, etc) into a desired shape. Once formed the plastic must cool so it can solidify. Heat must be removed from the molten plastic, and for this to happen the mold itself must be cooled. This may be accomplished by the mold being in contact with a solid heat sink, or by a flow of coolant through the mold.
Plastic molding produces components via techniques such as thermoplastic or injection molding, blow molding, rotational molding, thermoforming, structural foam molding, compression molding, and resin transfer molding (RTM). Services such as mold prototyping, low-volume production, high-volume production, insert molding, micro-molding, large-part molding, two-shot injection molding, reel-to-reel molding, machining, hot stamping, assembly, bonding, packaging and shipping are available.