(p407) Time management at the BOF meltshop 2 of ThyssenKrupp Steel Europe AG in Duisburg Beeckerwerth

摘要

The BOF meltshop 2 of ThyssenKrupp Steel Europe AG in Duisburg Beeckerwerth has a capacity of almost 6million mtpy at an average melt weight of 265 tons. Crude steel is produced with three converters and casted viatwo continuous casters. With respect to steel grades the sequences are produced in composite, so that especiallycontinuous caster 2 is able to cast without any setup time for more than 24 hours. The requested chemical analysisand temperatures are reached after tapping via several secondary metallurgy treatments.For production process' time management, a three-level planning system is used: First, the order of sequences toproduce is established for each continuous caster for up to 48 hours. Subsequently, the meltshop 2 planning tool isused for detailed planning until the end of the following shift. This tool is based on the software ODMS(Optimization Decision Management System) by IBM; hence, a (mixed integer) linear program is solved usingCPLEX. The weights in the combined objective function are influenced by the user by choosing the appropriateconfiguration. Further possibilities of interaction are offered by a graphical user interface in form of a Gantt chart. Aprovable optimal solution is found within 20 seconds. Finally the production process is monitored via the traffic lighttool: In order to determine whether the meltshop 2 planning tool result is still feasible, it is compared every tenseconds to the actual state in the BOF meltshop and at the continuous casters.Planning and traffic light tool have been put into operation in March 2012. Since then, the turn-round times havedecreased by 10% on comparable basis. Further advantages are a better usability of maintenance and downtimeperiods, an optimisation of required number of casting ladles and an increased predictability of production capacityin dependency of the casting programme.