利用宏观观察、化学成分分析、扫描电镜分析、显微硬度测试及有限元模拟等方法,对某超高压锅炉再热器集箱及疏水孔内壁裂纹的形成原因进行研究。结果表明:机组运行状态不稳定、疏水管设置不合理导致再热器疏水回流是集箱内部产生裂纹的主要原因。最后提出了改进措施,对保障机组的安全运行具有一定的指导意义。

Macroscopic observation, chemical composition analysis, scanning electron microscopy analysis, microhardness test and finite element simulation were used to study the causes of cracks on the inner wall of the header and drain hole of a super high pressure boiler reheater. The results show that the main reason for the cracks in the header was the hydrophobic reflux of the reheater caused by the unstable operation state of the unit and the unreasonable setting of the drain pipe. Finally, improvement measures were proposed, which had certain guiding significance for ensuring the safe operation of the unit.