NDT Techniques for Furnace Refractory Lining Assessment

Globally, thousands of metallurgical furnaces and process vessels are lined by several types of refractories. The harsh smelting conditions result in continuous refractory wear and deterioration which ultimately causes furnace to reline. For many vessels, the asset management workflow and refractory maintenance is predominantly proactive, and time based. Non-Destructive testing (NDT) methods can be utilized to change the traditional maintenance practices to a predictive and data-based decision-making function. In addition to reducing furnace refractory lining failures and molten metal leaks and run outs, this could potentially reduce the amount of highly toxically contaminated refractory waste disposal globally. In this paper, we review the NDT techniques that are utilized to determine refractory lining thicknesses and conditions in furnaces and process vessels.