末级过热器出口联箱疏水管焊缝裂纹分析及处理

Analysis and Treatment of Weld Cracks of Drainage Pipe of Last Stage Superheater Outlet Connector

某锅炉末级过热器出口联箱B侧疏水管(P91)的弯头下方焊缝在运行中发生泄漏,结合现场实际和初步检验,分析P91钢末级过热器出口联箱疏水管焊缝裂纹发生的原因主要是焊接工艺或热处理工艺参数不正确,工艺措施不严格,质量检验不严谨造成,以此为据拟定了缺陷焊缝修复的焊接热处理工艺及质量检验措施。

Leakage occurred in the drain pipe of the last superheater’outlet header in the welding seam under the elbow of a boiler’B side.Based on the field practice and preliminary inspection,the possible main causes of weld cracks in drain pipe of outlet header of last superheater of P91 steel are analyzed.The problem is found caused by incorrect welding or heat treatment process parameters,inadequate process measures and inaccurate quality inspection.Based on the conclusion,the welding heat treatment process and quality inspection measures for weld repair are proposed.