| 摘要 |
During casting of a mold for molding a tire, a vent hole of a mold is formed with accuracy by suppressing bending deformation of a wire disposed in a casting mold. By using a relational expression indicating a relation among a length L of a wire (20) in a casting space (14), a diameter D of the wire (20), a contact angle ¸ of the wire (20) with respect to a molten metal (3), and a bent amount W of the wire (20) by casting acquired by experiments in advance, the contact angle ¸ of the wire (20) at which the bent amount W of the wire (20) is within an allowable range is calculated from conditions of an actual length L and the diameter D of the wire (20). On the basis of the calculated contact angle ¸ of the wire (20), the wire (20) is disposed in the casting space (14) . By pouring the molten metal (3) into the casting space (14) in which the wire (20) is disposed, a cast metal (2) with the wire (20) cast-in in the casting space (14) is cast. A vent hole (4) is formed by withdrawing the wire (20) from the cast metal (2). |
