Compression Molding

Compression molding is a type of plastic molding. In the compression molding process, plastic is molded in an enclosed mold between two heated platens. Pressure in the range of 1,500 pounds per square inch is exerted on the material. In compression molding it is the combination of the plastic being compressed together and the heat from the platens that causes the plastic to become soft.

When the compression molding process is complete, a heavy and dense product is produced. Of all plastic products, those made from a compression molding process have highest electrical, heat and chemical resistance of any plastics material.

Many everyday products are made from compression molding. For example, handles for cooking pots, housings for hot plates, electrical receptacles, and high voltage switch housing are some of the heavier products constructed. Other products, such as kitchen utensils, cafeteria trays, and electrical boxes are also made through compression molding. Compression molding is not a process meant for bulk production.

By Murray Anderson