Integrated Production Planning and Scheduling Framework for TMT Bar Manufacturing Process

The production of steel is often considered a key indicator of a nation’s economic growth. The complex production environment of Thermo-Mechanical Treated (TMT) steel bar products, with multiple products of different diameters and grades, in the presence of sequence-dependent changeover times, requires efficient production planning and scheduling to ensure agile decision making and maximized profitability. In this work, we propose an integrated production planning and scheduling framework that, at the planning level, meets the intermediate product demands and maintains the inventory, while at the scheduling level ensures minimum changeover times and idle production periods to ensure maximum productivity. The proposed novel multi-grid discrete-time formulation and the resulting mixed-integer linear programming model demonstrate a significant reduction in the number of variables and constraints, increasing the computational efficiency. We further propose a rolling horizon implementation strategy to ensure an agile and alert decision making. We demonstrate the efficacy of the proposed optimization formulation on a real-world industrial TMT bar production facility in India.