Utilization of CON1D at ArcelorMittal Dofasco’s No. 2 Continuous Caster for Crater End Determination

Accurate determination of the position of final solidification point or crater end at ArcelorMittal Dofasco’s No. 2 Continuous Caster (CC) is essential for maximizing both casting speed and equipment utilization. The caster is equipped with one 900-mm long, straight, water-cooled copper mold, and produces 218-mm thick slabs with a maximum width of ~1,600 mm. The casting speed range at the caster is presently ~1.0 – 1.7 m/min. The position of the crater end or caster metallurgical length is defined as the distance from the liquid steel meniscus to the point at which the strand becomes completely solid, as shown in Figure 1 [1]. It is obvious that if the crater end extends beyond the machine length, the final portion of the partially solidified strand will no longer be supported by rolls on the strand broad faces. The ferrostatic pressure transmitted from the meniscus via the liquid pool and acting internally on the steel shell will then cause this unconstrained portion of strand to bulge out excessively. This will ultimately lead to a whale formation at the caster exit. To prevent extensive damage to the casting machinery, this catastrophic situation has to be avoided at all costs. In other words, the crater end must always be contained within the support roll segments under all casting conditions.