| 摘要 |
PURPOSE:To make possible a precision casting without the mixing of impurity and deformation and strain by connecting the intramold space in a self-curing and a non-consumable sprue tube with a lost foam sprue tube made of foaming resin and pouring molten metal while reducing the pressure in a molding flask. CONSTITUTION:The self-curing mold 1 composed of a shell mold furan resin or CO2 sand is embedded into the inner part of dry sand 4 or shot balls in the molding flask 3 capable of reducing pressure. Together with this, the intramold space in this self-curing mold 1 and the non-consumable sprue tube 7 are connected with the lost foam sprue tube 5 made of the foaming resin. Then, while reducing the pressure in the molding flask 3 through a gauze pipe 8 for pressure reducing, the molten metal is poured from the upper part of a sprue cup 11. The molten metal reaches the lost foam sprue tube 5 through the non-consumable sprue tube 7, and while melting the lost foam sprue, tube, the molten metal is cast into the intramold space in the self-curing mold 1 from a strainer hole 6. By this method, without wasting much molten metal, the development of shrinkage cavity at the outer part and blow hole, etc., can be prevented. |
