| 摘要 |
PURPOSE:To eliminate various kinds of casting defects accompanied with the development of heat decomposition gas at the time of casting, to improve the workability, to realize reduction of the equipment cost and to provide a high quality of thick casting by avoiding the development of the heat decomposition gas at the time of casting, eliminating a pattern by heating and forming a cavity for pouring the molten metal. CONSTITUTION:In a molding sand filling part 4 in a molding flask 6 parting the pattern 1 formed of a material which is lost by heating with a permeable parting plate 3, a thermosetting molding sand layer 7A is formed at the surrounding part of the pattern 1. This thermosetting molding sand layer 7A is embedded with the molding sand 7B, and by making the negative pressure of the cavity part 5 in the molding flask 6 or the high pressure of the cavity part 5 with feeding of combustion promoting gas, the air is performed in the molding flask 6. Together with this air permeation, by heating a sprue pattern 1A or a riser pattern 1B connected with the pattern 1, the pattern 1 is lost to form the cavity for pouring molten metal. |
