锅炉管道三通焊缝裂纹分析及预防研究

摘要

文中通过对HG-1900/25.4-YM7型600 MW超临界变压运行直流锅炉管道三通焊缝裂纹进行缺陷分析,结合金相和硬度检测,确定主蒸汽管道三通两侧焊缝设计不合理、主蒸汽管道管系与支吊架布置是造成缺陷焊缝的主要原因.提出了预防措施方案,对锅炉启停进行应力分析,对锅炉钢材蠕变疲劳问题进行寿命估算,结合应力分析与寿命估算进一步改进焊接技术,全方位地加强对焊缝的检验.%In this paper,a HG-1900/25.4-YM7 type 600 MW supercritical pressure transformer once-through boiler tube crack in the three way weld seam design was analyzed, metallographic and hardness testing were used.The improper design of main steam pipeline three way weld seam and main steam pipeline piping and support hanger layout were the main reasons cau -sing weld seam.A solution of preventive measures was proposed,the stress analysis of the boiler's start-stop was carried out,the lifetime of boiler steel creep fatigue problem was estimated.The welding technology is improved by combining the stress analysis and life estimation,and the weld inspection is strengthened in all directions.