Introduction
The traditional process for steelmaking resulted in blocks of steel known as ingots or billets, which then needed to be processed into useful forms.
In the traditional manufacturing process, steel was cast into ingots or billets, typically 600mm square in section and weighing about 20 tonnes. After stripping from cooling moulds the ingots were reheated before passing through a sequence of rollers to form slabs of steel typically 1500mm wide and 250mm thick, the exact size depending upon the intended finished product. These slabs were then subjected to further processing to produce engineering sections, such as angles, beams, columns or plate. This process requires considerable heat input in order to soften the steel and is therefore both expensive and inefficient.
Traditional ingot casting and subsequent re-processing has been widely replaced by continuous casting methods.
Continuous casting (concast) is superseding much of this process. The molten steel is poured into the top of a water cooled mould and the solidifying steel is drawn through at the bottom in a continuous operation to form a slab before it is further cooled and rolled into the final cross sectional shape. Because this continuous operation replaces several steps in traditional steel making, ie. Ingot casting, mould stripping, heating an soaking pits and primary rolling, considerable savings in energy and production costs have been achieved. In addition, it permits much tighter quality control.
