The models,algorithms and implementation results of a computerized scheduling system were introduced for the steelmaking-continuous casting process (SCCP) of a steel plant in China.The scheduling of SCCP in this plant required that each cast plan should be processed on time,the charges in the same cast should be processed continuously on the same caster,and the waiting time of the charges which are in front of each caster cannot exceed the given threshold.At the same time,the processing time of charges cannot be conflicted mutually in the same converters or refining furnaces.Based on the research background,a hybrid optimal scheduling approach and its application were discussed.Aiming at the main equipment scheduling,an optimal scheduling method was proposed which consisted of equipment assignment algorithm based on dynamic program (DP) technique and conflict elimination algorithm based on linear program (LP) technique.The approach guarantees that the charges are continuously processed on the same caster.Meanwhile,the requirement for high temperature ladle can also be satisfied due to the ladle matching function.Numerical results demonstrate solution quality,computational efficiency,and values of the models and algorithm.
In the steelmaking and continuous casting (SMCC) production process, operation time delay may lead to casting break or processing conflict so that the initial scheduling plan becomes unrealizable. Existing research methods are difficult to guarantee the accuracy of the model and successful application to actual applications. The rescheduling problem in response to operation time delay is firstly analyzed. This is then followed by the establishment of a novel multi-objective nonlinear programming model (MONPM). In specifications, a three-stage rescheduling method is proposed including the batches splitting (BS), forward scheduling method (FSM) and backward scheduling method (BSM). As a result, the real-time application shows that the proposed rescheduling method efficiently ensures the continuous casting and dramatically shortens the redundant waiting time for molten steel in very short rescheduling time.
In the process of tire production, vulcanization process is the last process and core process in the total pro...
Shengping Yu 1 , Diancai Yang 2 , Kehui Zhu 2 1. State Key Laboratory of Synthetical Automation for Process Industries (Northeastern University), Shenyang 110819, China2. Mesnac Co., Ltd, National Tire Technology and Control Engineering Technology Research Center, Qingdao 266045, China
