某亚临界机组锅炉分隔屏过热器在运行过程中发生爆管泄漏,采用宏观观察、壁厚测量、化学成分分析、拉伸试验、硬度测试、金相检验、扫描电镜及能谱分析等方法对其爆管原因进行分析。结果表明:分隔屏过热器受热面管受到吹灰蒸汽等冲刷作用,使过热器管局部出现了严重的冲刷磨损减薄,最终导致管子承压能力不足而发生局部破裂。

Tube explosion and leakage occurred in the boiler division panel superheater of a subcritical unit during operation. The causes of tube explosion were analyzed by means of macroscopic observation, wall thickness measurement, chemical composition analysis, tensile test, hardness test, metallographic examination, scanning electron microscope and energy spectrum analysis. The results show that the heating surface tube of division panel superheater was scoured by soot blowing steam, resulting in severe erosion wear and thinning of the superheater tube, which eventually led to insufficient pressure bearing capacity of the tube and local rupture.