针对某电厂1 000 MW超超临界塔式锅炉T23钢管焊接接头发生泄漏的问题，对接头裂纹进行了宏观检查和微观组织分析。分析表明，水冷壁管焊缝附近裂纹的形成原因主要是由焊接残余应力和焊接结构本身的拘束应力共同作用造成的。

The macro-inspection and microstructure analysis of cracks for welded joints were investigated, according to the leakage of T23 Steel tube welded joints in a 1 000 MW ultra supercritical tower-type boiler. The result shows that the water-wall tube weld cracks are caused by residual stress and structural binding stress of welded joints.