STRATEGIES TO OPTIMISE THE MILL AND HEAT PERFORMANCE OF A STEEL PLANT

摘要

Steels can be heat treated to produce an extensive range of microstructures and properties. A heat treatment cycle utilises the phase transformation during heating and cooling to modify the microstructure without the application of an external force. Common examples of heat treatment include hardening to increase strength and wear properties and annealing where ductility and toughness may be improved by reducing the strength or hardness. During the production of structural plate steels (for use in construction and ship building), normalised rolling practices are used to produce the final geometry and modify the structure. Accurate control of the processing window and rolling parameters is required to achieve final properties and performance that is comparable offline normalised plates. Developments in high powered cooling technologies offer potential benefits for other grades by achieving the final properties through online microstructure control rather than downstream processes. This paper demonstrates how high levels of process control coupled with mill experience, metallurgical expertise and modern cooling technologies can combine to maximise the potential for online finished product. This reduces the demand on the offline heat treatment capacity and potentially offers a steel plant options for reducing energy consumption whilst simultaneously optimising existing heat treatment cycles.