| 摘要 |
PURPOSE:To eliminate various kinds of casting defects accompanied with the development of heat decomposition gas at the time of casting, to obtain improvement of the workability and reduction of the equipment cost and to provide a thick casting having high quality by dissipating a pattern by heating while avoiding the generation of the heat decomposition gas at the time of casting to form a cavity for pouring molten metal. CONSTITUTION:The pattern 1 formed of material dissipated by heating is embedded into curable molding sand 7 filled in a molding sand filling part 4 in a molding flask 6 partitioned with a permeable partition plate 3. By making the cavity 5 in the molding flask 6 a negative pressure or by supplying combustion promoting gas into the cavity 5 to make the cavity a high pressure, ventilation in the molding flask 6 is executed. Together with the ventilation, by heating a sprue pattern 1A or a feeder head pattern 1B connected with the pattern 1, the pattern 1 is dissipated to form the cavity 10 for pouring the molten metal. |
