As to the leakages of tube-crust of the waste heat boiler in the secondary reformer of synthetic ammonia plant, welding stress in the welds between tubes an tube-sheets was analyzed via the finite element numerical computation. 针对合成氨二段转化废热锅炉管板易出现大量泄漏的问题,对管板与换热管角焊缝焊接应力进行了有限元分析。