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This paper studies a new scheduling problem in a steel plant, referring to continuous casting (CC), reheating furnace, and hot rolling (HR) processes, which is meaningful and important to the production efficiency and energy saving. First, the problem is modeled as a combination of two coupled subproblems: one assigns casts to continuous casting (CC) machines, decides sequence and start time for casts and rolling units; and another assigns furnaces and decides start time for rolling slabs in a reheating furnace. The objectives are to maximize the number of slabs processed in a mode of hot charge rolling or direct hot charge rolling so as to reduce the energy requirement and the temperature drop of slabs and minimize the residence time of slabs in a reheating furnace to save energy. Then, based on a Benders decomposition strategy, a hybrid algorithm that combines mixed-integer programming and constraint programming is designed to solve each subproblem. An effective cut-generation scheme based on a priority relationship is developed for resolving resource conflicts and unsatisfied setup time constraints. Finally, extensive experiments are conducted to verify the effectiveness of the proposed approach. Note to Practitioners—This paper deals with a scheduling problem arising from CC to HR process in steel manufacturing. It decomposes the original problem into a CC–HR scheduling problem and a reheating furnace scheduling problem. Previously, such a problem is handled, respectively, which always cause energy waste and mismatching plan. This paper takes complex technology constraints into full account to minimize energy waste and energy requirement and establishes nonlinear mathematical models for studied problems. Then, it designs a hybrid algorithm combined mixed-integer programming and constraint programming. The results demonstrate that the proposed approach can solve them effectively. The obtained solution gives decision makers some desired reference to determine a right schedule when actual production tasks are executed. [ABSTRACT FROM AUTHOR]

Hitherto existing investigations concerning the ceramic filter use in the steel making processes have given good results. The obtained results of filtration have proved that this method may be used as an effective and cheap way of steel filtration from non-metallic inclusions. Placing filters in the tundish is the best location considering the limitation of the possibility of secondary pollution of steel. Yet, the results presented in this paper, of an experiment prepared and carried out in the industrial environment, are the only positive results obtained, which are connected with so much quantities of liquid steel processed with use of the multi-hole ceramic filters.

Hitherto existing investigations concerning the ceramic filter use in the steel making processes (both of laboratory and industrial scale) have given good results. The obtained results of filtration (in the laboratory) have proved that this method may be used as an effective and cheap way of steel filtration from non-metallic inclusions. Placing filters in the tundish is the best location in consideration of limiting the possibility of secondary pollution of steel. Yet, the results presented in this paper, of an experiment prepared and carried out in the industrial environment, are the only positive results obtained, which are connected with so much quantities of liquid steel processed with use of the multi-hole ceramic filters.

Cu-8wt%Ag alloy was prepared by two kinds of preparation techniques, namely continuous casting + cold wire-drawing deformation preparation (CC + CD) and continuous casting + equal channel angular pressing + cold wire-drawing deformation preparation (CC + ECAP + CD), and subsequently the aging treatment was performed. We measured the mechanical property and the electrical property of the Cu-8wt%Ag alloy with different strains, explored the changing rules of the microstructure, the mechanical property and the electrical property by different preparation techniques. Then we analyzed the changing reasons of performance and discussed whether the better comprehensive performance could be acquired by combining the ECAP with the traditional cold-processing. The results show that the comprehensive performance of the Cu-8wt%Ag alloy prepared by CC + ECAP + CD is a little better than that by CC + CD. It is significant and valuable to solve the waxing and waning problem between the high strength and high conductivity of the Cu-Ag alloy. [ABSTRACT FROM AUTHOR]

Hitherto existing investigations concerning the ceramic filter use in the steel making processes have given good results. The obtained results of filtration have proved that this method may be used as an effective and cheap way of steel filtration from non-metallic inclusions. Placing filters in the tundish is the best location considering the limitation of the possibility of secondary pollution of steel. Yet, the results presented in this paper, of an experiment prepared and carried out in the industrial environment, are the only positive results obtained, which are connected with so much quantities of liquid steel processed with use of the multi-hole ceramic filters. [ABSTRACT FROM AUTHOR]

Hitherto existing investigations concerning the ceramic filter use in the steel making processes (both of laboratory and industrial scale) have given good results. The obtained results of filtration (in the laboratory) have proved that this method may be used as an effective and cheap way of steel filtration from non-metallic inclusions. Placing filters in the tundish is the best location in consideration of limiting the possibility of secondary pollution of steel. Yet, the results presented in this paper, of an experiment prepared and carried out in the industrial environment, are the only positive results obtained, which are connected with so much quantities of liquid steel processed with use of the multi-hole ceramic filters. [ABSTRACT FROM AUTHOR]