Method of changing the width of a continuous metal casting without interrupting the casting process

A method of changing the width of a continuously cast strand of rectangular cross-section without interrupting the casting process, wherein the strand is cast through a mold defining a cavity of rectangular cross-section with a longitudinal axis and having a small side wall which is displaceable with respect to the said longitudinal axis and is in contact with a small face of the strand, wherein said small side wall of the mold is displaced from an initial position to a final position, wherein a transitional section of the strand having a width which varies from an initial width to a final width is cast during a period of time when said small side wall is displaced from said initial to said final position, and wherein the improvement comprises the steps of:

• selecting a predetermined length for said transitional section of the cast strand,
• inclining the said small side wall by an angle whose tangent is substantially equal to the slope of the small face of the transitional section of the cast strand by pivoting the said small side wall from its initial position to a first intermediary position about a first axis extending slightly below the mold, the slope being defined between the small face of the transitional section of the cast strand and the plane containing the small faces adjacent the cast strand upstream and downstream thereof,
• displacing the said small side wall from said first intermediary position to a second intermediary position by pivoting it about an axis defined approximately by the intersection of planes defined by an inner face of the said small side wall positioned, respectively, in said initial and final position,
• displacing the said small side wall to said final position by pivoting it about a third axis extending approximately at the level of the free surface of the metal being cast in the mold,
• continuously measuring the length of the strand section cast from the beginning of the displacement of the said small side wall, and
• controlling the displacement of the said small side wall in response to the length of the strand section cast from the beginning of the said displacement so that the length of the transitional section of the cast strand equals said predetermined length.

A method of changing the width of a continuously cast strand of rectangular cross-section without interrupting the casting process, wherein the strand is cast through a mold defining a cavity of rectangular cross-section with a longitudinal axis and having a small side wall which is displaceable with respect to the said longitudinal axis and is in contact with a small face of the strand, wherein said small side wall of the mold is displaced from an initial position to a final position, wherein a transitional section of the strand having a width which varies from an initial width to a final width is cast during a period of time when said small side wall is displaced from said initial to said final position, and wherein the improvement comprises the steps of:

• selecting a predetermined length for said transitional section of the cast strand,
• inclining the said small side wall by an angle whose tangent is substantially equal to the slope of the small face of the transitional section of the cast strand by pivoting the said small side wall from said initial position to a first intermediary position about a first axis extending slightly below the mold, the slope being defined between the small face of the transitional section of the cast strand and the plane containing the small faces adjacent the cast strand upstream and downstream thereof,
• displacing the said small side wall from said first intermediary position to a second intermediary position by pivoting it about an axis defined approximately by the intersection of planes defined by an inner face of the said small side wall positioned, respectively, in the first and second intermediary positions,
• displacing the said small side wall to said final position by pivoting it about a third axis extending approximately at the level of the free surface of the metal being cast in the mold, and
• continuously measuring the length of the strand section cast from the beginning of the displacement of the said small side wall in response to the length of the strand section cast from the beginning of the said displacement so that the length of the transitional section of the cast strand equals said predetermined length.