Abstract: An analysis on width to thickness ratio of flat ingot at home and abroad has been carried out to get the effect of width to thickness ratio on quality of ingot. And the 60 t flat ingot with large width to thickness ratio and large water-cooling mould casting equipment are developed. The casting test of 61 t flat ingot with width 3 070 mm, thickness 1 022 mm, width to thickness ratio 3. 0 and casting temperature 1 580℃ of steel Q345B (/% : 0. 19C, 0. 36Si, 1. 39Mn, 0. 010P, 0. 003S) steelmaking by EAF-LF-VD process and rolled to 220 mm heavy plate has been carried out. Results by non-destructive testing and sampling analysis show that the quality of ingot is better； the heavy plate mechanical properties are yield strength 348 ~373 MPa, tensile strength 562 ~588 MPa, impact energy at -40 °C 40. 76 ~88・80 J, elongation 17. 00% ~28. 50% , Z direction reduction of area 33. 79% -60. 88% and rating of grain size 8 ~9 to meet the requirement of standard ； and the non-destructive testing results of heavy plate meets the requirement of JB/T4730-2005I -grade detection of defect. The commercial test shows that the technology of flat ingot water-cooling mould for large width heavy plate has the ability to provide bloom for high quality extra-heavy plate.

摘要： 对国内外扁钢锭的宽厚比进行了分析,并得出宽厚比对扁锭质量的影响。研发了60 t大宽厚比扁钢锭模和大型水冷模铸装备。对EAF-LF-VD冶炼Q345B钢（/%:0.19C,0.36Si,1.39Mn,0.010P,0.003S）浇铸成61 t扁锭（宽3070 mm,厚1022 mm,宽-厚比3.0,浇铸温度1580℃）,并轧成220 mm特厚板。探伤和取样试验结果表明,钢锭质量优良,钢板屈服强度348~373 MPa,抗拉强度562~588 MPa,-40℃冲击功40.76~88.80 J,延伸率17.00%~28.50%,Z向断面收缩率33.79%~60.88%,晶粒度89级,达到标准要求;钢板探伤性能达到JB/T4730-2005Ⅰ级探伤要求。工业试验表明,大宽厚板扁钢锭水冷模铸技术具备为高品质特厚板提供坯料的能力。

关键词: 601扁钢锭模, 锭型设计, 宽厚比, 特厚板, 水冷模, 性能