电站锅炉厚壁蒸汽管道焊接接头开裂原因分析

Welded Joint Cracking Cause Analysis of Steam Pipe with Thick Wall in Power Plant Boiler

通过宏观检查、成分分析、力学性能试验、金相检验、断口扫描电镜观察等试验方法及综合分析,对电站锅炉用厚壁蒸汽管道焊接接头开裂原因进行了分析。结果表明,焊接接头开裂泄漏的主要原因是由于焊接过程或焊后热处理控制不当,焊接接头中产生的再热裂纹在运行中承压扩展所致。

The power plant boiler steam pipe with thick wall causes of cracking of welded joint are analyzed by macroscopic, composition, mechanical properties, SEM for fracture and comprehensive analysis. The results show that the main reason for cracking and leakage of welded joints is due to improper welding process or heat treatment after welding, and the reheat crack in welded joint is caused by pressure expansion in operation.