电站TP304H钢末级过热器爆管原因分析

Analysis on the Causes of TP304H Final Super-heater Tube Burst in Power Plant

某电厂锅炉末级过热器发生爆管导致泄漏,通过宏观检查、化学成分分析、力学性能测试、金相组织检测等试验对原因进行分析。结果表明:管段化学成分、力学性能及显微组织等均符合标准要求,内外壁也未发现明显缺陷。结合现场工况分析爆管原因为启炉过程中过热器底部弯头发生了水塞现象引起管内蒸汽流动受阻,从而引起管段超温爆管。

Final superheater tube burst of the boiler caused the leakage in a power plant.The causes are analyzed through macro inspection,chemical composition analysis,mechanical performance testing,and metallographic examination,and combining the on-site working conditions.The results show that the chemical composition,mechanical properties and microstructure of the pipe section meet the standard,and no obvious defects are found on the inner and outer walls,but the water plug phenomenon occurred in the elbow at the bottom of the superheater during the start-up process,which caused the steam flow in the tube to be blocked,resulting in tube burst due to over-temperature.