300MW亚临界循环流化床锅炉中温过热器爆管原因分析

Cause Analysis of Pipe Explosion of 300MW Sub-critical Circulating Fluidized Bed Boiler Medium-temperature Superheater

针对某电厂#2炉中温过热器爆管事故,进行了常温拉伸、冲击试验、宏观形貌、金相组织分析及管内堵塞物合金元素成分分析。结果表明:中温过热器Ⅰ受热面管常温力学性能合格,金相组织发生了不同程度老化,短时过热导致爆管;堵塞物的元素成分与12Cr1Mo V一致,应为机械打磨及火焰切割中温过热器Ⅰ受热面管时产生的混合残留物。

For pipe explosion accident of No.2 furnace medium-temperature superheater in some power plant,analysis of normal temperature stretch, impact test, macroscopic morphology and metallographic structure andalloy element composition of blockage in tube were carried out. The result shows that： mechanical propertiesof heating surface tubes of medium-temperature superheaterⅠ is qualified, metallographic structure occurred ag-ing in varying degrees, short-time overheating caused pipe explosion; Blockage has the same element composi-tion with 12Cr1 Mo V, which should be mixed residues that mechanical polishing and flame cutting producedof medium-temperature superheater.