120 t LF采用新型钙线的工业实践

Industrial practice of new calcium wire in 120 t LF

为解决现场钙处理时收得率不稳定和钢渣飞溅严重的问题,马鞍山钢铁股份有限公司120 t LF采用新型无缝实芯纯钙线代替实芯纯钙线进行钙处理。通过理论探索,发现新型钙线由于涂敷有纳米硅粉作为中间层,可以更好的延长钙线熔化时间,使其打入钢液深处。通过理论计算,得出新型钙线的理论喂线速度为1.65 m/s。通过现场试验,发现当喂线速度为1.5 m/s时,新型钙线的收得率最高可以达到34.6%,而原钙线平均收得率仅为20.7%。且钢水中喂入新型钙线后可以大幅度减少大尺寸夹杂物,促进CaO-Al_2O_3复合夹杂物转变成为低熔点的C_(12)A_7,更能保证钢水的可浇性。

A new seamless pure calcium wire was boldly used to replace solid core pure calcium wire in 120 t LF of Masteel,in order to solve the problems of unstable yield and serious slag spattering in calcium treatment. It was found that the melting time of the new calcium wire could be prolonged and penetrated into the depth of molten steel due to the coating of nano-silica powder as the intermediate layer through theoretical exploration,and the theoretical feeding speed of the new calcium wire was 1.65 m/s through theoretical calculation. It was found that the highest yield of the new calcium wire was 34.6 % when the feeding speed was 1.5 m/s,while the average yield of the original calcium wire was only 20.7 % through field tests. And the large size inclusions could be greatly reduced and the CaO-Al2O3 composite inclusions could be transformed into C12A7 with low melting point by feeding new calcium wire into molten steel,which could better guarantee the pourability of molten steel.