| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a core for tube casting having an individual mirror image mark. <P>SOLUTION: The core for tube casting is molded as an annular body having an outwardly flange-shaped flange part 50 by solidifying cast sand with caking additive. A plurality of recessed mirror image marks are provided on the flange part 50 so as to provide a plurality of projecting cast mark on an end of a cast tube. A mark group of the mirror image marks is constituted of a main part P consisting of the mirror image marks (m) provided during the molding of the core, and an additional part P' consisting of a mirror image mark (m') formed by breaking a part of the core after the molding. Thus, the number of complicated replacement of molding dies can be reduced, and the number of the mirror image marks to be engraved in the core after the molding can also be reduced. Deep cut therefor can be omitted, and the core having individually different mirror image marks can be made without impairing the strength of the core. <P>COPYRIGHT: (C)2012,JPO&INPIT |
