This nozzle, with uniform structure, low infiltration to molten steel, strong erosion resistance, so it could be used for casting of most types of steel. A12O3-C submerged entry nozzle must be preheated to use, otherwise, the nozzle has the risk of cracking. In the preheating process, there will be graphite burning (decarburization), the nozzle surface layer apparent porosity increases, reducing its anti-erosion.
Another disadvantage of the submerged entry nozzle is poor slag resistance, good thermal conductivity, and thus the slag line is serious erosion and the inner wall of the nozzle is easy to condensate steel. It is necessary to take effective measures to protect submerged entry nozzle: such as add refractory fiber protective cover outside of the submerged entry nozzle, smear anti-oxidation layer on the surface, slag line with composite ZrO2-c material to improve slag erosion resistance and blow argon gas into the porous refractory layer on the inner wall of the nozzle.
There have many kinds of refractory products in our factory, such as refractory fire brick, refractory nozzle, refractory raw material and other refractory products. Welcome to view our website to know more information about refractory products.
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