русский
Both V process casting and lost foam casting are recognized as the third generation of physical molding methods after mechanical molding and chemical molding. Both of these casting processes use dry sand filling, vibration compaction, sealing sand box with plastic film, vacuum pumping to reinforce the mold and negative pressure casting. The two processes of V process casting and lost foam casting are complementary to each other, and their respective characteristics are compared in the following table:
| Lost Foam Casting vs Vacuum Casting | ||
| Item | Lost Foam Casting | Vacuum Casting |
| Suitable Castings | Small and medium-sized castings with complex cavities, such as engine block, engine cover | Medium and large castings with few or no cavities, such as cast iron counterweights, cast steel axle housings |
| Patterns and Plates | Foam patterns made by moldings | Template with suction box |
| Sand Box | Bottom or five sides exhaust | Four sides exhaust or with exhaust pipe |
| Plastic Film | The top cover is sealed by plastic films | All sides of both halves of sand box are sealed by plastic films |
| Coating Materials | Water-based paint with thick coating | Alcohol-based paint with thin coating |
| Molding Sand | Coarse dry sand | Fine dry sand |
| Vibration Molding | 3 D Vibration | Vertical or Horizontal Vibration |
| Pouring | Negative Pouring | Negative Pouring |
| Sand Process | Relieve negative pressure, turn over the box to drop sand, and the sand is then reused | Relieve negative pressure, then the dry sand falls into the screen, and the sand is recycled |
Both lost foam casting and V process casting belong to near-net forming technology, and it is easy to realize clean production, which is in line with the general trend of casting technology development, so it has broad development prospects.
