| 摘要 |
PURPOSE:To prevent the internal cracking of a large-sized and thick-walled hollow steel ingot and to form the ingot having defectless inside surfaces and internal characteristics by disposing a shinkable body into a composite core so that the shrinkage force to be generared during solidifying of the ingot is averted. CONSTITUTION:The titled device is installed with the core 4 consisting of a consumable shell 9 in direct contact with a molten steel 6 to be poured into said device, a cooling body 11, castable refractories 10 and the shrinkable body 12 at the center of an annular metallic mold 3 installed on a molding board 2 for a casting mold. The molten steel 6 is poured into the annular space between the mold 3 and the core 4 and is solidified, by which the thick-walled hollow steel ingot is obtd. The body 11 packed to the inside of the shell 9 accelerates the heat extraction and solidification of the molten steel 6 via the refractories 10 and the shell 9 by force cooling or self-heat capacity. The body 12 shrinks to cause the outside diametral contraction and deformation of the core 4, thereby decreasing the resistance by the thermal shrinkage of the inside solidified shell grown when the molten steel 6 is welded to the shell 9. |
