Analysis of damage mechanism of blow pipe castable

Aiming at the burning accident of the blow pipe of a blast furnace in Shougang, the quality of blow pipe castable was investigated, and the physical and chemical properties and slag resistance test were analyzed. According to the operating environment, the blow pipe castables were required to have the characteristics of high temperature resistance, scouring resistance, thermal insulation and thermal insulation. Mullite castable with aluminate cement was used, in which the medium temperature strength was reduced and the structure is easy to spalling, and it was susceptible to blast furnace slag erosion because of the poor slag resistance. It is suggested to improve the quality of raw materials and reduce the mass fraction of impurities, especially the influence of alkali metals on aluminate cement, add andalusite or kyanite as sintering agent which could improve the medium temperature strength and slag resistance of the castable and reduce the porosity, and thus greatly improved the overall service life of the blow pipe.