PURPOSE: To obtain a cast product accurate in weight by changing the tilting speed of a triangle ladle and tilting it for a fixed time, even when the quantity of molten metal in the triangle ladle is deficient or excess compared with the aimed level.

CONSTITUTION: At the time of supplying the molten metal 3 from the stationary ladle to the triangle ladle, when the molten metal surface in the triangle ladle reaches the aimed level 5, as the molten metal 3 is detected in a focus area A4 and not detected in a focus area A5, the triangle ladle is tilted in a prescribed speed to pour the molten metal into a mold. When the level of the molten metal 3 surface is lower than the aimed level and out of the permissible range, as the molten metal 3 is not detected in the focus areas A4 and A5, the triangle ladle is tilted at a high speed. When the level of the molten metal surface is higher than the aimed level 5 and out of the permissible range, as the molten metal 3 is detected by the focus areas A4 and A5, the triangle ladle is tilted at the low speed. Corresponding to the molten metal surface level in the triangle ladle, the tilting speed of the triangle ladle is adjusted to pour the molten metal into the mold.