Влияние условий истечения стали из промежуточного ковша на засорение насадок и погружных стаканов

Abstract

One of the important indexes for exploitation CCM is index of quantity high condition product per 1 ton liquid steel. During experimental investigations it was determine that high quality stoppers and submerged nozzles can provide necessity duration of casting without additional actions. In this case most important point is maximal lifetime of submerged nozzles. It was shown that as minimum two factors can result for destruction of submerged nozzle (Al-killed steels): erosion refractory in slag line, clogging of hole by Al2O3, slag’s drops and solidified steel clusters. Clogging effect in submerged nozzles causes by precipitation particles of Al2O3, slag’s drops and solidified steel clusters. It has big result with character flow motion in the inner part of submerged nozzle. It is shown that for Al-killed steel really lifetime of submerged nozzles is not enough for continuous casting with long sequence. Therefore it would rather to use system “nozzle-submerged nozzle” with possibility to change submerged nozzles time to time. For this system we can recommend to use argon injection cross stopper and argon protection joint chink between nozzle and submerged nozzle. It will improve alumina clogging suppression effects in 1,5–2,0 times.