Abstract: Effect of casting speed, super-heating degree of liquid steel in tundish on middle crack of cast blank and effec-t of mold cooling water technical parameters on shell thickness and <'enter crack of east blank for 40Cr steel φ150 mm tube blank during horizontal casting process have been studied by using pin shooting and infrared measuring temperature etc methods. Results showed that with casting speed 1. 99m/min, casting temperature 1 544 °C , super-heating decree of liquid steel in tundish- 45 °C , and mold intake water temperature 29. 3℃ , outlet water temperature 63. 4℃ , the liquid core length of cast billet was 17. 47 m, the rating of middle crack ≤0.1, and the rating of center porocity and center crack of cast billet was ≤l. 5 to meet the requirement of products.

Key words: Horizontal Casting, Steel 40Cr, Round Billet, Casting Process, Middle Crack

摘要： 采用射钉试验、红外测温等方法研究了40Cr钢φ150 mm管坯水平连铸时拉速和中间包钢水过热度对坯壳厚度和铸坯中间裂纹的影响,以及结晶器冷却水参数对铸坯中间裂纹的影响。结果表明,当拉速1.99 m/min,浇铸温度1 544℃,中间包钢水过热度45℃时,结晶器进水温度29.3℃,出水温度63.4℃,铸坯液芯长17.47 m,铸坯的中间裂纹≤0.1级,中心疏松和中心裂纹≤1.5级,满足产品要求。

关键词: 水平连铸, 40Cr钢, 圆坯, 拉坯工艺, 中间裂纹