Abstract: Aiming at the problem of submerged entry nozzle (SEN) clogging caused by poor fluidity of molten steel during the production of GCr15 bearing steel, an anti-flocculation flow SEN was introduced. The anti-flocculation flow SEN adopts carbon free anti-clogging technology in the inner cavity, which can inhibit the adhesion of inclusions, keep the steel flow channel clean during the casting process, and reduce the mold level fluctuation and flow field structure damage caused by the clogging of the casting channel. Carbon free liner material can also improve the thermal shock resistance of the nozzle and avoid the abnormal phenomenon caused by thermal shock in the nozzle slag line during the casting start. In order to further improve the cleanliness of molten steel and reduce the MgO·Al₂O₃·CaS inclusions in bearing steel, the casting test of calcium-free treatment molten steel was carried out by using the anti-flocculation flow nozzle. The test results showed that there were no significant fluctuations in the mold liquid level during whole casting 8 flows, and the anti-flocculation flow effect of the inner layer material at the nozzle was stable. The nozzle diameter had almost no shrinkage (shrinkage of 0.4-2.0 mm), and the cleanliness of the molten steel was improved while maintaining stable production.

Key words: bearing steel, fluidity of liquid steel, clogging of nozzle, anti-flocculation nozzle, calcium treatment