PURPOSE: To efficiently execute casting of a large deformed tube in good quality by winding a lost foam material corresponding to the tube thickness on the outer circumferential surface of a core and casting to the one forming the outer circumference to the outer shell layer of rapid bonding mortar.

CONSTITUTION: The core 11 corresponding to the inner diameter of the casting tube in the outer diameter is formed by stamping sand and facing material is coated on the outer circumferential surface. To the outer circumferential straight part of this core 11, a foaming styrene sheet 12 is wound and fixed by a paper tape 13. The shape corresponding to a flange part of the casting tube, too, is formed by fixing the foaming styrene divided pieces. Successively, by spraying the rapid bonding mortar on the whole outer surface of this foaming styrene, the outer shell layer 16 is formed. The molding sand 23 is stamped on the circumference of the outer shell layer, and by pouring molten metal from a sprue 24, the large deformed casting tube can efficiently be manufactured in the good quality.