X70管线钢洁净度控制研究

Research on Cleanliness Control of X70 Pipeline Steel

针对某钢厂中厚板卷厂采用铁水倒罐→铁水预处理→转炉冶炼→出钢脱氧合金化→LF精炼炉→RH真空炉→钙处理→连铸生产X70管线钢生产工艺,采取系统取样分析,对P、S等杂质元素,N、H、O等气体的脱除规律以及夹杂物的控制规律进行了研究。研究表明,成品成分可以稳定控制水平为:w([P])≤0.004 5%,w([S])≤0.001 00%,w([O])≤0.000 85%,w([N])≤0.003 00%,w([H])≤0.000 15%,夹杂物以小于10μm的CaO-CaS为主,且单位面积总夹杂物数量小于12个/mm^2,成品钢具有很高的洁净度水平。

The system analysis is carried out in accordance with molten iron change tanks→mohen iron pretreatment→converter smelting→ tapping dioxidation alloying-→LF refining furnace→RH vacuum furnace→calcium treatment→continuous casting productive XT0 pipeline steel production technology in a steel factory. Study on P,S etc. impurity elements,N,H,O etc. gas removing regulation,and inclusion control regulation is carried on. Reasearch results show that finished products components can be controlled in a stability level：w（[P]）≤ 0.004 5%,w（[S]） ≤0.001 00%,w（[O]） ≤0.000 85%,w（[N]）≤0.003 00%,w（[H]） ≤〈0.000 15%,the inclusion is less than 10 Ixm CaO-CaS as the leader and the inclusion total number in unit area is less than 12/mm2, finished steel has very high cleanliness level.