Research Progress on Anti-clogging Technology of Submerged Entry Nozzles for Continuous Casting

The causes,the formation process,and the prevention of submerged entry nozzle(SEN)clogging were introduced.The influence of electric field on the SEN clogging was focused on,including the basic theory and measurement of SEN charging,the preliminary research on SEN charging,the influence of molten steel on the wetting behavior of refractory materials in electric field,and the influence of electric field on the oxide inclusions in molten steel.Based on the influence of the hydrodynamics,chemistry and other factors on refractory materials,structure,inclusion particle transfer and adhesion,many anti-clogging researches have been carried out,such as optimizing process conditions,compositing anti-clogging inner lining materials,innovating SEN structure and applying physical fields,which solve the problem of SEN clogging to a certain extent.However,the problems of weak adaptability and superficial study on clogging mechanism are still prominent.The electric field control is a new technology to prevent clogging.Although it has achieved certain results in on-site continuous casting trials,some problems such as the method of applying electric field,the electric field parameters and the equipment still need to be gradually improved,and the surface characteristics of inclusions and SEN materials at high temperatures need to be further studied.It was pointed out that the combination of materials and applied electric field will become an important direction for SEN anti-clogging technology.