氧化皮脱落导致的过热器管爆管分析

某电厂高温过热器运行5万h后连续发生爆管，通过对爆管及割管样品的宏观形貌、机械性能、金相以及材料状态等进行综合分析，确定爆管原因与氧化皮脱落导致的堵塞有关。对此，提出了杜绝快速起停，适当延长停炉后的打开炉门时间，安装锅炉管寿命管理系统等建议和措施。

ANALYSIS OF SUPERHEATER'S TUBEBURST CAUSED BY FALLINGAWAY OF OXIDE SKIN

Tube-bursts of the high-temperature superheater in one powr plant had successively occurred after 50000h operation, through integrated analysis, including macroscopic structure, mechanical property, and metallurgical analyses of tube-samples from tube-burst and tube-cut sections, as well as evaluation of tube material status etc., it is believed that the causes leading to tube-burst are related to blockage caused by falling-away of oxide skin. Then, some recommandations and measures have been put forward, such as preventing rapid startup and shutdown, suitably lengthening the time to open furnace gate after boiler shutdown, and mounting management system for monitoring the service life of boiler tubes etc..