Lost foam metal casting process technology-foamcast

Technology of lost foam metal casting process

This pattern is made from expanded polystyrene foam. The final pattern is approximately 97.5% air 2.5% polystyrene.
The foam is coated with ceramic investment, also known as refractory coating, by dipping, brushing, spraying or flow coating. The coating creates a barrier between the smooth foam surface and the coarse sand surface. The coating also controls permeability, which allows the gas created by the vaporized foam pattern to escape through the coating into the sand. The coating foams a barrier so that the molten metal does not penetrate of cause sand erosion during pouring.
After the coating dries, the cluster is placed into a flask and backed up with un-bonded sand. The sand is then compacted using a vibration table. Once compacted the mold is ready to be poured.
Molten metal is then poured into the EPS pattern, which vaporizes and is replaced by metal. Vents in the side of the flask allow vapor to escape.
The ceramic investment is then removed, revealing the metal part.

Process & Operating principle

1. Mold foam pattern sections.
2. Age pattern to allow dimensional shrinkage.
3. Assemble pattern if it is a multiple piece pattern.
4. Build cluster (multiple patterns per cluster).
5. Coat cluster.
6. Dry coating.
7. Compact cluster in flask.
8. Pour metal.
9. Extract cluster from flask.

Main equipments

•Vacuum stablized system:

•Molding system:

•Sand reclamation system