The Lost Foam casting process eliminates the need for sand binders and cores. The sand is unbonded and a foam patternis used to form the shape of the casting. The foam pattern is "invested" into the sand at the Fill & Compact process stationallowing the sand into all voids and supporting the foam patterns external form. The sand is introduced into the flaskcontaining the casting cluster and compacted to ensure all voids and shapes are supported. The flask is transported to thepouring operation. The foam is evaporated as the metal is poured allowing the metal to take the shape of the castingcluster. Separation of sand and metal is accomplished at a Flask Dump Station. With no binders in the sand this processis performed with ease. Systems can be designed to accommodate quenching operations if required. The clusterproceeds to the casting finishing area for sprue, gate and riser removal. The sand is reprocessed by classification andcooling to be re-used. Thermal reclamation of the sand will extend the useful life. Lost Foam offers an environmentallyfriendly process with the added advantage of more accurate casting.

Foam patterns are created from polystyrene beads. The beads start as hard granules, very similar in size and shape tosand granules. The beads are expanded, allowed to stabilize and then molded into the desired shape. More complexshapes require multiple patterns to be glued together. The assemblies are then attached to a generic, central foam piececalled a tree. Multiple patterns can be produced on a single tree. After assembly, the entire tree is dipped into a refractorycoating to strengthen the tree. The assembled, strengthened tree is attached to a pouring funnel (called a sprue) andplaced into the flask.