PURPOSE: To provide a stoke for differential pressure casting, which is suitable to separating method of a product and molten metal by supplying inert gas and is easily restored at the time of developing accident.
CONSTITUTION: In the stoke 10 for differential pressure casting, having an inner cylinder 11 connecting the upper end with a sprue in a metallic mold and holding the lower end higher than the surface 8 of the molten metal 7 in a holding furnace and an outer cylinder 12 closing the upper end at between this cylinder and outer face of the inner cylinder 11 and submerging the lower end into the molten metal 7 and arranging a hole 14 for communicating annular range formed between the inner and outer cylinders 11, 12 with the outer part, the inner cylinder 11 is made as possible to be inserted into/removed from upper part and outer diameter 11a of the inner cylinder 11 is gradually reduced downward. As the other way, the inner cylinder 11 is made as possible to be inserted into/removed from upper part and formed with material having coefficient of thermal expansion larger than that of the outer cylinder 12.
ONISHI SANETSUGU
IIZUKA YASUO
YASHIRO TOSHINORI
