Patent ID: 9545662
Date: 2017-01-17
CPC Classifications: B22D

Claim:
1. A method for vertical direct chill molten metal casting comprising: providing a mold cavity framework with a rigid first side and a rigid second side opposite the first side, a third side and a fourth side opposite the third side, with inner surfaces of the first side, second side, third side and fourth side defining a mold cavity disposed to receive molten metal; providing a vertically movable bottom block configured relative to the mold cavity to contain molten metal entering the mold cavity upon startup; providing molten metal to the mold cavity; moving the bottom block downward at a predetermined rate; providing a programmable logic controller that controls the movement of the first side such that the movement of the first side is correlated to a level of the molten metal surface relative to an upper portion or a lower portion of the first side; and moving the first side and the second side of the mold cavity framework relative to one another during casting and thereby varying dimensions of a resulting castpart during casting while maintaining the level of the molten metal surface at a predetermined location relative to the mold cavity framework such that the level of the molten metal top surface moves from a level at a middle portion or upper portion of the first side to the lower portion of the first side and the second side during an inward movement of the first side and second side, to impart an inward taper on a top portion of the resulting castpart.