As manufacturing systems have become more complex, uncertainties and disruptions have increased, where resilience has become essential for manufacturers, in order to ensure production continuity and quick adaptations to disruptions such as equipment failures, supply chain issues, or the introduction of new products. This work presents an approach of assessing resilience in steel manufacturing, using the Penalty of Change (PoC) methodology. Combining PoC with a heuristic scheduling algorithm, the goal is to simulate and evaluate the impact of disruption. Resilience is quantified by measuring the degree of production deviation caused by disruptions such as machinery breakdowns and unplanned orders with high priority. Through a case study of a steel manufacturing plant, the proposed framework offers a clear methodology for assessing resilience and identifying areas for improvement. This study emphasizes the importance of resilience in manufacturing, offering a practical tool for decision-makers to optimize production planning and enhance operational robustness under certain conditions.