转炉炼钢厂钢包包衬耐材的改进

Improvement of refractory for liquid steel ladle in BOF steel-making plant

通过现场调研发现炼钢生产中存在着如下问题:1)在转炉炉役中后期,铸造吊车长期处在满负荷运行,存在一定的安全隐患;2)钢包装120 t钢水时,上部净空只有200~300 mm,不符合钢包炉的使用要求(钢包炉要求净空400~600 mm);3)钢包耐材寿命低、耐材消耗高、工人劳动强度高;4)钢包包役后期,包壳外表面温度偏高,接近蠕变温度,存在一定的安全隐患。针对上述问题开展了以下工作,并取得了良好的效果:1)通过调整精炼渣系、合金化配方、加强钢包耐材和砌筑质量等措施后,钢包侵蚀速率由2.5 mm/次降低至1.1 mm/次,钢包寿命从平均67次提高到157次;2)为了保证钢包出钢量在120 t时,上部净空满足精炼的要求,将钢包工作层厚度减少30 mm,钢包包衬寿命由平均157次调整至127次;3)由于减薄包衬和调整永久层的材质,使钢包耐材总量降低3.8 t,钢包最大总质量由180 t减至176.2 t,铸造吊车使用更加安全;4)由于永久层选用了保温性能好的耐材,包壳外壁温度由280~292℃降至252~262℃,远低于钢材的蠕变温度,满足钢包安全使用的要求;5)钢包耐材改进后,耐材、合金、造渣料、电耗、电极等消耗显著降低,吨钢成本降低12.16元。

On the basis of site investigation,some problems in the production of BOF steelmaking were found.1)The ladle cranes were running at a full capacity in the middle&later stages of converter lining service,there was a potential hidden danger.2)When the weight of liquid steel in ladle reached 120 t,the space height above liquid steel in the ladle was between 200 mm and 300 mm,that was not satisfied with the requirement of ladle furnace(400-600 mm).3)The life of the ladle lining was low,the consumption of lining was high,the labor intensity of workers was high.4)In the later stages of ladle lining service,the surface temperature of ladle approached creep temperature,there was also a potential hidden danger.Therefore,the following works were carried out,and some good results were got.1)By adjusting the refining slag composition and the alloy kinds and proportion,enhancing the quality of lining and masonry,the eroding rate of ladle lining decreased from 2.5 mm to 1.1 mm at a heat,the life of ladle lining raised from 67 heats to 157 heats.2)In order to ensure the height space above liquid steel in the ladle satisfied with the refining requirement when the weight of liquid steel in ladle reached 120 t,the thickness of working layers was cut down 30 mm,the life of ladle lining was adjusted from 157 to 127 heats.3)Because of reducing thickness of work layers and adjusting the material of permanent layers,the weight of ladle lining reduced 3.8 t,the weight of ladle with lining&liquid steel decreased from 180 t to 176.2 t,ladle cranes were safer.4)Because of permanent layer with the good thermal insulation property,the surface temperature of steel ladle decreased from 280-292℃to 252-262℃,the steel ladles were safer.5)After reform of refractory for liquid steel ladle,the consumption of the lining,alloys,refining slag,electrical power and electrode significantly reduced,the producing cost reduced 12.16 yuan/t.