连铸开浇首炉二次氧化程度对比与分析

Comparison and Analysis of Secondary Oxidation Degree in the First Heat of Continuous Casting

对比了两种不同中间包氩气置换方式的效果,方案一采用氩气杆的方式置换中间包内腔的空气,方案二采用中间包盖氩气管和氩气杆的共同作用的方式置换中间包内的空气。选择相同的钢种、规格、置换时间及管道压力,开展工艺试验。通过比较得出:(1)方案二更能有效地置换中间包内腔的空气,减少二次氧化的概率;(2)方案二的氧含量、氮含量、Als/Alt、钢中夹杂物等指标均优于方案一,说明方案二的保护浇注效果更好;(3)方案二可有效预防10μm以下夹杂物的产生,尤其是2μm≤X<5μm的小颗粒夹杂物。

Compares the effects of two different tundish argon replacement methods,schemeⅠuses the argon rod to replace the air in the inner cavity of the tundish,and schemeⅡuses the joint action of argon gas pipe and argon rod on the tundish cover to replace the air in the tundish.Select the same steel grade,specification,replacement time and pipeline pressure to carry out the process test.Through comparison:(1)schemeⅡcan more effectively replace the air in the inner cavity of the tundish and reduce the probability of secondary oxidation;(2)The oxygen content,nitrogen content,Als/Alt,inclusions in steel and other indicators of schemeⅡis better than those of schemeⅠ,indicating that the protective casting effect of scheme II is better;(3)SchemeⅡcan effectively prevent the formation of inclusions below 10μm,especially small particle inclusions in the range of 2μm≤X<5μm.