采用宏观形貌检查、化学成分分析、力学性能测试、金相组织检验及扫描电镜分析等方法,对某660MW超临界燃煤发电机组锅炉中部螺旋水冷壁T2钢内螺纹管的渗漏事故进行分析。结果表明,T2钢内螺纹管渗漏处的线性裂纹是在热轧成荒管时因工艺不当或管坯表面存在缺陷而形成的。建议制造厂加强对热轧荒管表面质量的检查;电厂对同批T2钢内螺纹管端头进行扩大检查,及时发现并消除类似缺陷。 The leakage of T2 steel threaded tube in central spiral water wall of a 660MW supercritical coal-fired generator set was analyzed by macroscopic appearance examination, chemical composition analysis, mechanical property test, microstructure test and scanning electron microscope analysis. . The results show that the linear cracks in the leakage of T2 steel internal thread pipe are formed when hot rolling into waste pipe due to improper process or defects on the surface of the tube. It is recommended that the manufacturer strengthen the inspection of the surface quality of hot rolled waste pipe; the power plant will expand the inspection of the same batch of T2 steel internally threaded pipe ends to detect and eliminate similar defects in time.