Abstract: Because the sulphur content in steel NVA32(0. 12~0. 18C,1.30～1.60Mn)increases to 0.020% at 210 t BOF melting end point from original 0.005%,it shall be added 1000 kg binary synthetic slag CaO-CaF₂ and added  200 kg aluminium during BOF tapping and added Si-Mn alloy and Si-Al-Ba alloy to decrease sulphur content in steel by  0.007%～0.008% with desulphurization rate up to 30%.During LF refining,sulphur content in steel further decreases to  0.001%～0.002% by further added 800 kg synthetic slag,blown argon 600~900 L/min,after heating fed 600 m silicon- calcium wire then blown argon 30~45 L/min for 10 min with end slag basicity R = 4.5～5.5.

摘要： 因210tBOF冶炼终点NVA32(%:0.12～0.18C、1.30～1.60Mn)钢中硫含量由0.005%升高至0.020%,通过BOF出钢过程加入1000kg二元合成渣CaO-CaF₂、200kg铝粒,并加入硅锰和硅铝钡合金,可使钢中硫含量降低0.007%～0.008%,脱硫率达30%。在LF精炼时,通过进一步加入合成渣800kg,600～900L/min吹氩,加热后喂600m硅钙线,30～45L/min吹氩10min,终渣碱度R=4.5～5.5,钢中硫含量进一步降低至0.001%～0.002%。

关键词: 氧气转炉, 出钢脱硫 , LF 精 炼, 超 低 硫 钢