Expandable plastic steam molding

There are, however, some techniques unique to foamed plastics. When working with expanded polystyrene (EPS) beads, for example, to produce cups, picnic dishes, etc., various steam-chest molding methods are used. Based on the blowing agent used (pentane gas, etc.) the application of steam causes the beads to expand and fixse together in a perforated mold. 

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