中国冶金
中國冶金
중국야금
CHINA METALLURGY
2015年
4期
7-11
,共5页
重轨钢%洁净度%均质性%质量控制
重軌鋼%潔淨度%均質性%質量控製
중궤강%길정도%균질성%질량공제
heavy rail steel%cleanliness%homogeneity%quality control
高速铁路对重轨钢质量提出了更高的要求,洁净度与均质性控制是其质量提升的关键。包钢高速重轨钢采用无铝脱氧工艺降低钢水全氧质量分数、VD 真空脱气工艺强化脱氢、全程保护浇注与中间包冶金防止钢水二次氧化和促使钢中夹杂物上浮,提高钢的洁净度;通过合理控制钢液过热度、严格控制拉速、采用结晶器电磁搅拌、动态二冷、动态轻压下控制等关键技术来减轻和消除铸坯中心偏析,提高钢的均质性。生产实践表明,高速重轨钢中w T [O]≤0.0020%、w [N]≤0.0050%、w [H]≤0.00015%、w [Al]≤0.0040%,A 类夹杂物不超过2.0级,B、C、D 类夹杂物不超过1.0级,中心 疏 松 评 级 不 超 过1.0级 的 比 例 平 均 为 83.1%,中心缩孔不超过0.5级的比例平均为94.3%,中心碳偏析指数最大为1.07。包钢高速重轨钢综合质量满足了《时速200 km 客运专线铁路用钢轨标准》的要求。
高速鐵路對重軌鋼質量提齣瞭更高的要求,潔淨度與均質性控製是其質量提升的關鍵。包鋼高速重軌鋼採用無鋁脫氧工藝降低鋼水全氧質量分數、VD 真空脫氣工藝彊化脫氫、全程保護澆註與中間包冶金防止鋼水二次氧化和促使鋼中夾雜物上浮,提高鋼的潔淨度;通過閤理控製鋼液過熱度、嚴格控製拉速、採用結晶器電磁攪拌、動態二冷、動態輕壓下控製等關鍵技術來減輕和消除鑄坯中心偏析,提高鋼的均質性。生產實踐錶明,高速重軌鋼中w T [O]≤0.0020%、w [N]≤0.0050%、w [H]≤0.00015%、w [Al]≤0.0040%,A 類夾雜物不超過2.0級,B、C、D 類夾雜物不超過1.0級,中心 疏 鬆 評 級 不 超 過1.0級 的 比 例 平 均 為 83.1%,中心縮孔不超過0.5級的比例平均為94.3%,中心碳偏析指數最大為1.07。包鋼高速重軌鋼綜閤質量滿足瞭《時速200 km 客運專線鐵路用鋼軌標準》的要求。
고속철로대중궤강질량제출료경고적요구,길정도여균질성공제시기질량제승적관건。포강고속중궤강채용무려탈양공예강저강수전양질량분수、VD 진공탈기공예강화탈경、전정보호요주여중간포야금방지강수이차양화화촉사강중협잡물상부,제고강적길정도;통과합리공제강액과열도、엄격공제랍속、채용결정기전자교반、동태이랭、동태경압하공제등관건기술래감경화소제주배중심편석,제고강적균질성。생산실천표명,고속중궤강중w T [O]≤0.0020%、w [N]≤0.0050%、w [H]≤0.00015%、w [Al]≤0.0040%,A 류협잡물불초과2.0급,B、C、D 류협잡물불초과1.0급,중심 소 송 평 급 불 초 과1.0급 적 비 례 평 균 위 83.1%,중심축공불초과0.5급적비례평균위94.3%,중심탄편석지수최대위1.07。포강고속중궤강종합질량만족료《시속200 km 객운전선철로용강궤표준》적요구。
High quality of heavy-haul rail steel is necessary for high-speed railway.Therefore,improving the cleanli-ness and homogeneity of high-speed heavy rail steel are the key technologies for improving the product quality. Technologies such as using the oxidizing technology of non-Aluminum,vacuum degassing (VD),protecting cast in all process and the tundish metallurgical technology,strict casting speed and molten steel temperature control,M-EMS,dynamic secondary cooling and dynamic soft reduction control technologies were used in Baotou Steel.The practice shows that in the high-speed heavy rail steel,w T [O]≤0.002 0%,w [N]≤0.005 0%,w [H]≤0.000 15%,w [Al]≤0.004 0%,non-metallic inclusions category A ≤2.0 level,while B ,C and D ≤1.0 level.The average rate of center looseness index≤1.0 is 83.1%,the average rate of center shrinkage cavity index≤0.5 is 94.3%,and the highest index of carbon central segregation is 1.07.The quality of the production can meet the requirements of “rail standards for the 200 km/h speed railway line for passenger transportation”.