Continuous casting of steel includes multiple transfer operations of liquid steel from ladle to mold via tundish, followed by its solidification to semi-finished products such as blooms, billets or slabs. Since the transfer operations can easily result into reoxidation of liquid steel, it presents significant challenges in terms of retaining the steel quality obtained through secondary metallurgical operations such as ladle refining, vacuum degassing or RH degassing. Over the years, the transfer operations have seen significant improvement due to increasing usages of slide gates, ladle shrouds, ladle nozzles, flow modifiers such as impact pads, weirs dams and so on [1]. Injection of inert gases into the ladle shrouds has also turned out to be a common practice as it creates a protective gas blanket which prevents air ingress and subsequent reoxidation.
Although a lot has been done, one aspect of transfer operation which has largely gone unnoticed is the misalignment of ladle shroud. On careful observation, it can be noticed that ladle shrouds become tilted with respect to the vertical direction.
Recently, Chattopadhyay et. al. and Chatterjee et. al. have pointed out continuous casting operations in both billet caster and slab caster with misaligned ladle shrouds, as depicted in Figure1. The luminous circular regions and dark cylindrical regions depict tundish open eyes (TOEs) and ladle shrouds respectively. Ladle shroud misalignment affects steel quality and operation as it undermines the performance of impact pad and dams causing adverse flow conditions, increasing the chance of open eye formation, decreasing residence time for inclusion flotation along with increasing refractory wear in continuous casting.