Continuous casters' specific types introduction 01

At present, there are five types of continuous casters used all over the world: vertical, vertical bending, arc, oval and horizontal.

The pouring operation, crystallization solidification, secondary cooling, cutting and other processes of the vertical continuous caster are carried out in sequence on the vertical line. The vertical bending caster is vertical first, then bent 90 ° into a horizontal shape after the slab solidifies, and then cut and transported out. The height of the equipment is lower than that of the vertical caster. Arc caster is to pour molten steel into the arc mold, then run along the arc track, pass through a quarter arc, and then discharge the billet in the horizontal direction. Its equipment height is further lower than that of vertical bending type. Based on the further improvement of arc continuous caster, oval continuous caster appears. The horizontal continuous caster is currently in the development stage.

According to incomplete statistics, among the continuous casters built in the world, 17% are vertical, 21% are vertical bending, 55% are arc and 7% are other forms. At present, the newly-built continuous caster is the most arc-shaped.

Characteristics of vertical continuous caster

The main equipment of vertical continuous caster from tundish to cutting station are arranged on a vertical line. The whole fuselage stands on the ground plane of the workshop or is arranged in a deep pit underground. This kind of continuous caster occupies a small area and has compact equipment; High temperature billet has no bending deformation and less surface and internal cracks; The inclusions in the non solidified liquid in the slab are easy to float up, and the molten steel is relatively "clean"; The secondary cooling device and pinch roll are simple in structure and easy to maintain. The disadvantages of vertical continuous caster are: the fuselage is up to 20 ~ 40m, the plant must be raised or the pit must be deeply excavated, and the capital construction cost is expensive; Because the height of the caster cannot be increased too high, it can only be poured at low speed and the productivity is low; The static pressure of molten steel is large, which is easy to make the solidified shell bulge (called bulge), resulting in the deterioration of slab quality.

Characteristics of vertical bending continuous caster

Compared with the vertical continuous caster, the height of the body of the vertical bending continuous caster is reduced and the investment is saved; It is easy to lengthen the body and realize high-speed pouring; The inclusions in the non solidified liquid steel in the billet are easy to float up and the inclusions are evenly distributed. The disadvantage is that because the billet needs to be bent and straightened once, it is easy to produce internal cracks; Although the height of the caster is reduced, the capital construction cost is still high.

There are two forms of vertical bending continuous caster: one is that there is a vertical section under the mold. When the slab is fully solidified or nearly fully solidified, the top bending enters the arc section and then straightens. It is mainly applicable to billet. The other is a straight crystallizer plus a vertical section (2 ~ 3M), with liquid core multi-point bending or gradually bending into the arc section, and then straightening. The advantages of this caster are as follows: 1) there is a vertical section, which can fully float the inclusions in the liquid cavity; 2) The slab is bent at many points or gradually, which avoids the local concentration of bending deformation stress and effectively reduces the formation of cracks; 3) The bending with liquid core can increase the drawing speed and improve the productivity of caster. At present, in order to solve the quality problem of arc inclusion agglomeration in the slab of arc caster, the construction of vertical bending caster has an increasing trend.