Analysis of Erosion Mechanism of Wear‐Resistant Layer in Large Blast Furnace Tuyere

Abstract

The blast furnace tuyere is a crucial component for blast furnace production. The frequent damage of the copper tuyere impedes the smooth operation of the blast furnace. Welding a wear‐resistant layer on the tuyere can extend its service life, but it still falls short of the expectation in a large blast furnace. In this article, it is aimed to elucidate the erosion mechanism of the wear‐resistant layer. A scanning electron microscope, an energy dispersive spectrometer, and an optical microscope are employed to examine the morphology, composition, and metallographic structure of the samples obtained from a 5800 m3 blast furnace tuyere in China, as well as to calculate the frequency of daily slag crust shedding from cooling staves. The results indicate that the main cause of the erosion of the wear‐resistant layer is the shedding of slag crust due to the temperature fluctuation of the cooling staves. Finally, the erosion mechanism of the wear‐resistant layer is proposed. It is suggested that the formation and propagation of cracks caused by erosion of slag and hot metal are the primary failure mode of the wear‐resistant layer.