The application of magnesia-spinel castable to the snorkel in the RH degasser

With a range of applications in secondary metallurgy, the development of magnesia-spinel castable for monolithic linings has been improved the wear of linings and lower costs for the inner and outer of the snorkel in the RH degasser. The cold crushing strength of the magnesia castable decreases with an increase of firing temperature. That should be shown by the formation of cracks due to the high thermal expansion of periclase. There is no sintering shrinkage curing firing at 1500 degrees C due to the formation of spinel (Mg-Al2O4) from the reaction of periclase and alumina in the fine grain at high temperature. The magnesia-spinel castable consists of sea water sintered magnesia, spinel alumina of fine grain of main materials, thixotropic binder of non-cement. and micro-silica. We have been trying the application of magnesia-spinel castable in the snorkel instead of the outer part usage as hi-alumina castable and the inner part usage of MgO-Cr2O3 bricks.