Estudo de caso da análise de falha de um rolo puxador de uma laminação de tiras a quente e viabilidade de reparo

In the highly competitive global steel industry, achieving economic sustainability is paramount. This study investigates a failure involving shaft end breakage in Pinch Rolls, which are critical components repaired for a Hot Strip Mill (HSM). Through the application of Root Cause Failure Analysis (RCFA), the primary cause of the failure was identified as a brittle fracture of the shaft end, initiated by crack propagation in the recovered surface layer. Microstructural analysis revealed that the cracks were associated with the brittleness of the martensitic structure in the heat-affected zone (HAZ), resulting from an inadequate welding process. Based on the findings, the study highlights the feasibility of repairing the component using a properly designed procedure, thus contributing to improved reliability and cost-effectiveness in industrial operations.